CLU-IN Technology Innovation News Survey

AK ARCTIC NWR BIG RAM LAKE SOIL & HAZARDOUS MATERIALS (SOL) [Market/Commercialization]

Fri, 5 Jun 2026 20:20:25 GMT

U.S. Department of the Interior, Fish and Wildlife Service, SAT Team 1, Falls Church, VA
Contract Opportunities on SAM.gov 140FS126Q0104, 2026

This is a total small business set-aside under NAICS code 562910. The Fish and Wildlife Service seeks a contractor to assess and characterize a potential petroleum spill at Big Ram Lake in Alaska to determine whether contaminated soil and groundwater are present and whether remediation is necessary. Environmental sampling and analysis will include petroleum hydrocarbons, volatile organic compounds, PAHs, and total lead in accordance with Appendix F of the 2024 ADEC Field Sampling Guidance for AVGAS. The contractor will prepare a site characterization and remediation plan/report for the spill and, if corrective action is required, develop a cost proposal as part of a Corrective Action Plan. In addition, asbestos, lead-based paint, and PCB-containing paint evaluations will be conducted for buildings slated for demolition, with a separate hazardous materials report documenting identified materials, estimated quantities, and associated remediation or removal cost estimates. Big Ram Lake is located in the Arctic National Wildlife Refuge in Alaska and can only be accessed by float plane. It is a remote location with limited facilities. There are several buildings (i.e., Cook Shack, Sleeping Cabin, and Outhouse) but absolutely no other amenities. The award will be a firm-fixed-price contract with a period of performance from June 22 to December 31, 2026. Offers are due by 11:59 PM CDT on June 7. https://sam.gov/workspace/contract/opp/d71a9bc31b0949059d0f7bb9b65fd96c/view

TWENTY-FIVE YEARS OF RESEARCH AND MONITORING USING PUF DISK PASSIVE AIR SAMPLERS [General News]

Fri, 5 Jun 2026 17:28:36 GMT

Eng, A., Y.-M. Hsu, T. Harner, J. Mastin, and S. Wheadon.
Environmental Science & Technology 60(16):11833-11870(2026)

Polyurethane foam (PUF) disk-based passive air samplers (PASs) have become a pivotal tool in research and monitoring of persistent organic pollutants and emerging chemicals in ambient air in the gas phase and on ambient particulate matter. Their low cost and ease of use have facilitated deployment at the regional and global scales. Modifications to the polyurethane foam (PUF)-PAS have expanded its use for more specific purposes, such as the sorbent-impregnated PUF-PAS (SIP-PAS), which improves sorptive capacity for more volatile chemicals, and the passive dry deposition (PAS-DD) sampler, which captures larger particles and enables estimation of gas and particle deposition. The review summarizes studies characterizing uptake rates and partition coefficients of PUF disks for a wide range of compounds and evaluations of sampler design and performance. It synthesizes applications of PUF-PAS, SIP-PAS, and PASDD from 2000 through 2024 across ambient air measurements, indoor air quality, source emissions, health, and, most recently, biodiversity. Approximately 650 publications employing PUF disk-based PASs are summarized, demonstrating their increasing use and diversification. On the horizon, the PUF-PAS will likely continue to transform and integrate fields of science and inform policy. https://pubs.acs.org/doi/pdf/10.1021/acs.est.5c17602?ref=article_openPDF

RECENT ULTRATRACE PER- AND POLYFLUOROALKYL SUBSTANCE (PFAS) DETECTORS [General News]

Fri, 5 Jun 2026 13:35:02 GMT

Park, J. and S. Park. Nanoscale 11(2026)

This review discusses advances in PFAS detection made over the last five years in organic molecules and assemblies, polymers, nanoparticles, carbon nanotubes, and metal-organic frameworks, highlighting how tailored recognition motifs and controlled assembly convert PFAS binding into optical, electrochemical, or resistive signals. Representative strategies discussed include interrupted energy transfer and amplifying fluorescent polymers for ratiometric and turn-off fluorescence sensing; molecularly imprinted and nanostructured electrodes for impedimetric and voltammetric quantification; single-particle collision electrochemistry and MXene-metal hybrids for ultralow electrochemical detection; printed surface-enhanced Raman spectroscopy substrates for molecular fingerprinting; and 2D conductive MOFs for chemiresistive ppt-level responses. Analytical performance, selectivity trends across chain length and headgroup chemistry, matrix effects in real waters, and practical considerations for onsite deployment are evaluated. The review concludes by identifying key challenges (stability, standardization, and multiplexed detection) and outlines promising directions toward translating ultratrace PFAS sensors into robust environmental monitoring tools.

PHYTOREMEDIATION OF LOW-CONCENTRATION CR(VI)-CONTAMINATED SOIL FROM A SUPERFUND SITE USING SUNFLOWER (HELIANTHUS ANNUUS L.) WITH CONCURRENT BIODIESEL PRODUCTION FROM HARVESTED SEEDS [Research]

Fri, 5 Jun 2026 13:34:47 GMT

Hadiuzzaman, M., S.T. Sabuj, and J. Liu. | Bioresource Technology Reports 32:102308(2025)

A study evaluated the feasibility of using sunflower (Helianthus annuus L.) for simultaneous phytoremediation of low-level Cr(VI)-contaminated soil and biodiesel production. Soil was collected from a remediated Superfund site with low residual Cr(VI) concentrations (0.16 ± 0.04 mg/kg), and controlled pot experiments were conducted under two amendment conditions (low-nitrogen chemical fertilizer and biosolids) to assess plant growth, Cr(VI) uptake, biodiesel quality, and microbial responses. In addition, bioaccumulation factors and translocation factors were assessed to evaluate the efficiency of chromium uptake and movement within the plant. Cr(VI) was absorbed by the roots and translocated to shoots, leaves, and seeds, with both amendments achieving comparable phytoextraction efficiencies. Biosolids amendment significantly enhanced plant biomass compared to chemical fertilizer, while no visible phytotoxicity symptoms were observed, indicating that sunflower tolerated the low-level Cr(VI) contamination. Biodiesel extracted from the seeds met ASTM standards for acid value and density, confirming its potential as a renewable fuel. Microbial biomass carbon and nitrogen in the rhizosphere increased after phytoremediation, suggesting a beneficial role of soil microbes in supporting plant growth and remediation. The study demonstrates that integrating sunflower-based phytoremediation of low-level Cr(VI) with biodiesel production provides a sustainable and cost-effective strategy for addressing residual contamination while contributing to renewable energy generation.

LEAD TRANSFORMATION TO PLUMBOJAROSITE REMAINS STABLE FOLLOWING LIME ADDITION FOR LEAD AND ARSENIC CONTAMINATED SOILS [Research]

Fri, 5 Jun 2026 13:34:26 GMT

Blackmon, M.D., T.D. Sowers, A.R. Betts, C. Jiang, and K.D. Bradham.
Journal of Hazardous Materials 506:141540(202

Stability experiments were performed at simulated field conditions for six weeks to assess jarosite-based remediation efficacy at environmentally nominal pH conditions. Smelter-impacted and legacy pesticide (lead arsenate) contaminated soils (SM and LP, respectively) were evaluated. Soils were adjusted to a range of pH conditions using either CaCO₃ or Ca(OH)₂ to facilitate growth of centipede and perennial ryegrass. Grass growth occurred in limed samples from pH 4.3-8.6 with XAS-confirmed PLJ stability over six weeks. Lead in vitro bioaccessibility (IVBA)% results for all treated soils were consistent with PLJ formation, showing averaged reductions of 77.3-8.0% and 81.6-11.0% post treatment in LP and SM soils, respectively, with a reduction in As IVBA% across all soils.

DNAPL-RESPONSIVE HYDROGEL NANOREACTOR ENCAPSULATING NZVI FOR ENHANCED DEGRADATION OF CHLORINATED CONTAMINANTS IN GROUNDWATER [Research]

Fri, 5 Jun 2026 13:34:12 GMT

Sang, K., Z. Li, X. Tao, C. Chen, M. Chen, H. Gao, J. Xu, J. Hou, K. Yang, and D. Lin.
Environmental Science & Technology 60(11):8734-8748(2026)

Nanoscale zerovalent iron (nZVI) reactors (nZVI@PNIPAM) via in situ reduction of incorporated Fe³⁺ ions were fabricated by engineering DNAPL-responsive poly(N-isopropylacrylamide) (PNIPAM) hydrogels with precisely controlled hydrophobic domains. Hydrogel encapsulation enabled nZVI to remain well-dispersed, spontaneously penetrated porous media, and significantly suppressed side reactions with water. The nanoreactors leveraged the selective interaction between DNAPLs and PNIPAM's hydrophobic functional groups as a trigger, exposing encapsulated reactive nZVI exclusively at contamination interfaces through a rapid conformational transition and dehydration of PNIPAM. This interfacial interaction yields unprecedented efficiency, achieving 4.4-12.3-fold higher electron utilization for degradation of seven typical chlorinated solvents than conventional nZVI, while suppressing water corrosion over 600-fold. Field-relevant evaluations demonstrated consistent performance across broad hydrochemical conditions (pH 6-9, 0-1,000 mg/L KCl, 0-200 mg/L natural organic matter), with >90% DNAPL removal in real contaminated groundwater. The mechanistic discovery of pollutant-responsive activation represents a significant advance over current diffusion-limited approaches, potentially revolutionizing targeted in situ groundwater remediation strategies.

CHARACTERIZATION OF THE POTENTIAL LONG-TERM IMPACT FROM SEDIMENTARY PFAS AT A HISTORICALLY CONTAMINATED TEXTILE WASTE SITE [Research]

Fri, 5 Jun 2026 13:33:57 GMT

Snook, J., J. Becanova, S. Vojta, and R. Lohmann. | ACS ES&T Water 6:521-528(2026)

Two sites in Rhode Island have textile-mill-associated waste retention ponds known to introduce PFAS contamination to the adjacent river, estuary, and eventually the Atlantic Ocean. The retention ponds were investigated as a long-term source of PFAS via water passive sampling, sediment coring, and laboratory-derived partitioning coefficients, Kd, with field sediment and water. Additional studies were performed to assess mobility and estimate the mass fluxes of PFAS from sediment to water. Retention pond 1 was more contaminated (up to 26 ng/L PFOA in water and 74 ng/g PFTrDA in sediment). Derived log Kd values ranged from 1 to 5 for most PFAS, indicating a shift from relative mobility to high storage potential in sediment. Estimated loss fluxes from the sediment varied between 5 and 228 μg/m2/year, resulting in desorption times from three years for FPeSA to >100 years for FOSA. The combined evidence suggests that if left untreated, the textile mill retention pond constitutes a source of long-term contamination to the river. https://pmc.ncbi.nlm.nih.gov/articles/PMC12797218/pdf/ew5c01210.pdf

IN SITU XANES STUDY OF PFAS IMPACTED SOILS FILLED WITH AQUEOUS AND NON-AQUEOUS PHASES [Research]

Fri, 5 Jun 2026 13:33:44 GMT

Kumar, A., M.K. Alam, B. Qian, M.J. Donn, D.A. Navarro, J.L. Rayner, G.B. Davis, B. Cowie, B. Pejcic, and S. Fisher. Journal of Contaminant Hydrology 277:104820(2026)

The partitioning of PFAS in a spiked agricultural soil and an AFFF-impacted "aged" soil was investigated under various soil moisture conditions and when the soil pores were filled with NAPL. Sulfur (S) K-edge X-ray absorption near edge structure (XANES) spectroscopy was used to probe S speciation in situ, and spectra were analyzed using a Gaussian Curve Fitting approach. Six major S species were identified in both soil and PFAS partitioning behavior was interpreted based on changes in sulfonate fractions, representing sulfonic acid-based PFAS. In the spiked soil, sulfonate fractions increased the most when soil pores had a water saturation ratio of 0.25, whereas in the "aged" soil the most significant increase occurred for completely saturated soil pores. These differences were attributed to differing micellar formation behaviors in freshly spiked versus AFFF-impacted "aged" soil. A linear correlation was also observed between the ratio of total reduced S and sulfonate fractions against the degree of saturation of "aged" soil. In spiked soil, a lower percentage of NAPL content at SW = 0.25 led to higher partitioning of sulfonic acid-based PFAS. https://www.sciencedirect.com/science/article/pii/S0169772225003250/pdfft?md5=ff03cc5a6b6d04116587d83e8f52bdd1&pid=1-s2.0-S0169772225003250-main.pdf

COMPLEMENTARITY OF PASSIVE SAMPLING AND COMPOSITE AQUEOUS SAMPLING TO ASSESS PFAS EMISSIONS IN INDUSTRIAL WASTEWATER [Research]

Fri, 5 Jun 2026 13:31:26 GMT

Hensel, T., J.-H. Hein, P. Krystek, A. Togola, T. Reemtsma, and F. Zietzschmann.
ACS EST Water 6(3):2008-2017(2026)

This study evaluates the capability of a polar organic chemical integrative sampler, a Speedisk sampler, and flow-through tube passive samplers (PS) to enhance PFAS monitoring in industrial wastewater. Effluent from a textile manufacturer, an industrial laundry, and a semiconductor facility (all ≥10,000 m³a discharge) was sampled over two work weeks. Passive sampling using the three samplers was conducted, while an automated aqueous sampler obtained continuous composite wastewater samples. Composite samples revealed fluctuating concentrations of up to 18 different PFAS (varying by site) with total loads from 0.12 mg/day (semiconductor manufacturer) to 8.8 mg/day (industrial laundry). The PS detected up to 19 additional PFAS compared to aqueous samples, revealing multiple representatives of legacy PFAS as well as precursor compounds (6:2 FTAB, 6:2 FTS), differing by site. Quantitative assessments from PS in the complex industrial matrices remained inconclusive and need further examination. This study highlights the in situ enrichment potential of PS as sensitive and low-maintenance qualitative tools.

TIME DOMAIN INDUCED POLARIZATION MONITORING FOR ENHANCED REMEDIATION OF DNAPLS DURING IN-SITU MICROEMULSION FLUSHING [Demonstrations]

Fri, 5 Jun 2026 13:31:11 GMT

Zhao, R., X. Guan, A. Gu, J. Meng, X. Huang, S. Liu, and D. Mao.
Environmental Earth Sciences 85:165(2026)

Alternating time domain induced polarization (TDIP) measurements and injection/pumping operations were conducted at a CHCl3-contaminated weathered andesite site. Full-decay TDIP data were inverted and correlated with groundwater sampling to reflect contaminant solubilization and reagent distribution. Interpretation results demonstrated that TDIP provided spatially continuous electrical imaging in the entire remediation volume, capturing the footprints of CHCl3-contaminated groundwater and the remediation reagent. The injected reagent exhibited strong conductivity and polarization contrasts with contaminated groundwater, confirming its spread across most of the weathered andesite layer. Thresholds of m=50 mV/V delineated CHCl3 contamination zones exceeding the regulatory limit of 300 µg/L. Reagent spreading along profiles revealed preferential flow paths within highly permeable fracture zones. Chargeability reduction correlated with DNAPL desorption showed >90% removal efficiency in groundwater samples, although residual contamination persisted in heavily contaminated zones. Microemulsion flushing effectively enhanced DNAPL solubilization, while weathered andesite medium and excessively high injection velocity limited remediation effectiveness. This article is Open Access at https://link.springer.com/article/10.1007/s12665-026-12901-9.

NONTARGET GC-ECNI-ORBITRAP-HRMS SCREENING AND EVALUATION METHOD USED TO IDENTIFY POLYHALOGENATED COMPOUNDS EXTRACTED FROM TWO PASSIVE AIR SAMPLERS DEPLOYED AT MARINE ISLANDS IN AUSTRALIA [Demonstrations]

Fri, 5 Jun 2026 13:30:50 GMT

Schweizer, S., G. Korkmaz, J. Hauns, A.R Schachtele, X. Wang, C. Paxman, J. Mueller, and W. Vetter. | Science of the Total Environment 1020:181579(2026)

Gas chromatography with electron capture negative ion high-resolution mass spectrometry (GC-ECNI-OrbitrapHRMS) was applied for the comprehensive analysis of halogenated natural products (HNPs) and anthropogenic organohalogen compounds in two passive air samples from Australian marine islands. This enabled the detection of ~250 halogenated compounds in the two air samples, of which reference standards were available for only ten. For the evaluation, the compounds were listed according to the exact mass of the nonhalogenated backbone (halogens in the molecular formula were replaced with hydrogens; primary list) calculated in the next step. Compounds with the same backbone were listed together, which was crucial for data interpretation. Specifically, the ~250 compounds could be traced back to ~100 different backbones. Four additional secondary lists were calculated to indicate structurally related homologues if their exact masses were also found in the primary list. Key findings include the detection of several sponge-derived HNPs and >20 halogenated nitrobenzenes and nitrophenols, including iodine-containing ones. The primary and secondary list-based evaluation may be a promising approach for other complex datasets with polyhalogenated compounds. https://www.sciencedirect.com/science/article/pii/S0048969726002391/pdfft?md5=4ab3daa765fb27c1aab39b088505234d&pid=1-s2.0-S0048969726002391-main.pdf

FIELD TEST OF A SCALED-UP BIOELECTROCHEMICAL SEQUENTIAL REDUCTIVE/OXIDATIVE PROCESS FOR CHLORINATED ALIPHATIC HYDROCARBONS (CAHS) REMEDIATION FROM CONTAMINATED GROUNDWATER [Demonstrations]

Fri, 5 Jun 2026 13:30:35 GMT

Dell'Armi, E., P. Ciampi, A. Marchetti, E. Bartsch, M. Alesi, E.J. Alesi, G. Rehner, B. Matturro, V. Feigl, M. Molnar, S. Rossetti, M.P. Papini, and M. Zeppilli.
Chemical Engineering Journal 524:169825(2025)

This study presents the performance of a scaled-up sequential anaerobic/aerobic bioelectrochemical system (BES) integrated with a groundwater circulation well system that was applied to a CAH-contaminated site in Northern Italy. The pilot system, consisting of four 105 L modules, operated under three different hydraulic retention times and potentiostatic conditions. Maximum tetrachloroethane removal was 1.23 mg/L/d, with a coulombic efficiency of 0.83%. The study includes aquifer geological characterization, essential for assessing the long-term behavior of the DNAPL source, and microbial analysis of the inoculum used to prime the system. Ecotoxicity tests were conducted on both influent and effluent to evaluate environmental risks. Results showed slight initial toxicity for Aliivibrio fischeri but no adverse effects on protozoa, plants, or Daphnids. This study represents the largest effort to scale up a bioelectrochemical process to remediate CAHs, and one of the largest bioelectrochemical pilot installations overall in terms of the electrode active area. Findings highlight both the potential and the challenges of scaling up BES for CAH remediation. https://www.sciencedirect.com/science/article/pii/S1385894725106682/pdfft?md5=3fb2260c148e963413ed5af001790cf7&pid=1-s2.0-S1385894725106682-main.pdf

PHYTOREMEDIATION OF AN ACID TAR PIT AT CINDERHILL, DERBYSHIRE, UK: LESSONS LEARNED AND FUTURE CHALLENGES [Demonstrations]

Fri, 5 Jun 2026 13:30:19 GMT

Johnson, M.F., H. Wood, S. Bryan, S. Craig, W. Meredith, C. Snape, and C.N. Uguna.
Journal of Environmental Management 405:129690(2026)

Monitoring results are presented from a large-scale field trial (30 m×16 m area) of willow (Salix) phytoremediation at an acid tar pit at Cinderhill, UK. Before the trial, tars had not degraded since deposition in the 1970s; however, after planting with willow spilling, evidence of degradation was clear, showing a reduction in n-alkane and PAH concentrations. After 2 years, tar breakdown was only recorded in close association with willow root systems, but after 3 years it was documented in tars not targeted by root growth. Willow also stabilized the tar pit surface, altered its topography, and enabled the establishment of a diverse understory flora and, along with initial liming of the area, contributed to reduced surface pH from highly acidic to neutral. eDNA of microbial communities in tars near willow roots was highly distinct from tars away from roots and surrounding soil. The community around willow roots included species known to process PAHs and hydrocarbons, and also species that aid vegetation growing in stressful environments. Challenges and unforeseen issues during the trial, future work, and knowledge gaps are discussed. https://www.sciencedirect.com/science/article/pii/S0301479726011503/pdfft?md5=1922d0d50b64049799ea08efde31b8dc&pid=1-s2.0-S0301479726011503-main.pdf

COMPLETE DECHLORINATION VIA BIOAUGMENTATION IN PARTIALLY WEATHERED AND FRACTURED BEDROCK [Cleanup News]

Fri, 5 Jun 2026 13:30:04 GMT

Shores, C. | DCHWS East, 4-6 March, Philadelphia, PA, 17 slides, 2026

Remedial response was implemented to achieve complete TCE dechlorination in partially weathered and fractured bedrock using bioaugmentation techniques. The site contained extensive TCE contamination, affecting ~1.5 acres and extending >200 feet deep within saturated partially weathered rock (PWR), saprolite, and fractured bedrock zones. Initially, the PWR was thought to be relatively unsaturated and less significant. However, additional well installations identified substantial TCE contamination within these zones, leading to a revised conceptual site model and the implementation of a focused feasibility study evaluating enhanced bioremediation approaches. Biotreatability evaluations showed favorable pH, temperature, and oxidation-reduction conditions for biological treatment, although naturally occurring Dehalococcoides bacteria were not detected, and daughter product formation was minimal. The remedial strategy centered on bioaugmentation using specialized microbial cultures and electron donor amendments to stimulate reductive TCE dechlorination. A pilot study demonstrated significant TCE reductions and achieved a radius of influence of up to 25 ft; however, complete dechlorination to ethene was not achieved because microbial populations remained below target concentrations and pH conditions likely inhibited bacterial activity. Lessons learned were incorporated into the full-scale remedial response. The final design included permanent injection wells isolated within the partially weathered rock interval, increased buffering capacity to address pH challenges, use of the more robust KB-1 Plus® microbial culture, and significantly higher bacterial dosing. Modifications greatly improved microbial activity and dechlorination performance throughout the source areas. Monitoring results after one year showed Dehalococcoides bacterial concentrations averaging 1.3 × 10^⁸ gene copies/L, well above the project target of 10^⁷ gene copies/L. Significant reductions in TCE and total CVOCs were observed throughout both shallow and deep source areas, including intervals between 45 and 111 ft bgs. The core of the dissolved contaminant plume was effectively eliminated, and the overall plume began to contract as source area concentrations decreased. https://mediacdn.guidebook.com/upload/213717/0EICrVTYvCPT5hB7KoNhNkm2KnkGWTQUDyLb.pdf

FRACTURING METHODS TO DELIVER LIQUID AMENDMENTS TO LOW PERMEABILITY AND HETEROGENEOUS SETTINGS – METHODS AND CASE STUDIES [Cleanup News]

Fri, 5 Jun 2026 13:29:49 GMT

Ross, C. | DCHWS East, 4-6 March, Philadelphia, PA, 19 slides, 2026

This presentation highlights two case studies where fracturing technologies, hydraulic injections, and enhanced delivery systems were used to improve contaminant treatment efficiency and overcome limitations associated with conventional injection methods. The first case study involved a PCE-contaminated site in California, where ZVI was combined with electron donor injections to stimulate enhanced bioremediation and in situ chemical reduction. Specialized fracturing technologies were implemented to improve amendment distribution in low-permeability formations. Sand-filled fracture-enhanced wells were used for SVE, combined with high-velocity water jetting and hydraulic fracturing techniques to create preferential flow pathways for amendment delivery. Fracture-enhanced wells enabled the successful operation of a full-scale SVE system and removal of ~46 lbs of PCE before asymptotic conditions were reached. Groundwater monitoring data showed substantial reductions in PCE and daughter products over time following the injection events, demonstrating effective contaminant degradation and treatment progress. The second case study focused on the Lake City Army Ammunition Plant Area 17B Oil and Solvent Waste Pits, where silty clay and weathered shale limited groundwater flow and amendment distribution. Conventional gravity injection wells achieved relatively low flow rates ranging from 1.0-7.7 gal/d/well. To improve remedial performance, fracture-enhanced injection wells were installed using sand-filled hydraulic fractures connected to the injection wells. Following fracturing, injection performance improved dramatically, with flow rates increasing to 7.8-109 gal/d/well. The enhanced amendment delivery system improved radius of influence and significantly increased contaminant treatment efficiency. Groundwater monitoring results demonstrated treatment reductions ranging from 92% to >99% for total chloroethenes, although some areas associated with NAPL contamination showed lower treatment efficiency. https://mediacdn.guidebook.com/upload/213717/cNnymBhW2PjuIBTrYhhBMa2Eqxp2SkEWk3XG.pdf

IN SITU MONITORING CONSOLIDATION AND HARDENING BEHAVIORS OF AN HDPE GEOMEMBRANE-CEMENT-BENTONITE COMPOSITE CUTOFF WALL [Cleanup News]

Fri, 5 Jun 2026 13:29:33 GMT

Jin, W., Z.-K. Wang, X.-X. Dou, Q.-L. Wang, and Y.-C. Li.
Groundwater Monitoring & Remediation 46(2):33-43(2026)

An in situ multi-parameter monitoring system that includes soil pressure, pore water pressure, and bulk electrical conductivity was installed in a 23.5-m deep HDPE-cement-bentonite (HCB) cutoff wall. The data collected from the first 20 d are presented. The shallow zone (≤2.5 m) became unsaturated after 2 d, triggering surface settlement, CB mixture-geomembrane or CB mixture-trench sidewall detachment, and shrinkage cracks; the intermediate zone (5-7.5 m) developed 80-kPa suction on Day 4, while deeper responses lagged. Lateral pressure showed a V-shaped trend, an initial hydration-induced drop followed by a pressure increase due to bentonite swelling. Bulk electrical conductivity (3000-4000 mS/m) decreased overall but varied with the permeability of surrounding soil. The temperature evolution comprised three distinct stages: hydration heating, cooling, and stabilization.

MULTIPLE AWARD MILITARY MUNITIONS SERVICES (MAMMS IV) INDEFINITE DELIVERY/INDEFINITE QUANTITY (IDIQ) MULTIPLE AWARD TASK ORDER CONTRACT (MATOC) (SRCSGT) [Market/Commercialization]

Fri, 5 Jun 2026 13:29:16 GMT

U.S. Army Corps of Engineers, Sub Command 1, 2, 3, Engineer Division North Atlantic, Baltimore District, Baltimore, MD
Contract Opportunities on SAM.gov W912DR27RA001, 2026

This is a sources sought notice for marketing research purposes only. The U.S. Army Corps of Engineers, Baltimore District, requests letters of interest from qualified contractors interested in performing work on the potential Multiple Award Military Munitions Services Multiple Award Task Order Contract in support of the Environmental Munitions Design Center under NAICS code 562910. The scope involves a wide range of military munitions and environmental services at various sites known or suspected to have been affected by military munitions, Munitions and Explosives of Concern, and Munitions Constituents, with emphasis on addressing CERCLA and RCRA process timelines and requirements. Specific efforts will include all phases of the CERCLA/RCRA process, including, but not limited to, site inspections, remedial investigations, feasibility studies, remedial designs, remedial actions, remedial operations, and long-term management. Additional desired capabilities include investigative and intrusive aspects of MEC and MC remediation, address characterization and/or remediation of co-mingled MEC, MC, and HTRW hazards during all phases of CERCLA and RCRA processes, and the ability to simultaneously manage multiple teams performing work at multiple locations under firm-fixed-price task orders. The Government is exploring the possibility of utilizing a firm-fixed price with economic price adjustment and would like industry feedback on experiences and any benefits seen from it. Although not deemed to be a "Munitions and Explosive of Concern," Small Arms Ammunition (SAA) may be encountered during any phase of the CERCLA and/or RCRA process. Capabilities must include Dynamic Advanced Geophysical Classification and SLAM-based positioning for investigation and cleanup. Letters of interest are due by 12:00 PM EDT on June 29, 2026. https://sam.gov/workspace/contract/opp/bab777c21dc141f0837f3542d9de0b6c/view

AK-KODIAK ADMIN SITE-SOIL CLEAN-UP (SOL) [Market/Commercialization]

Fri, 5 Jun 2026 13:26:02 GMT

U.S. Department of the Interior, U.S. Fish and Wildlife Service, FWS, Construction A/E Team 1, Falls Church, VA
Contract Opportunities on SAM.gov 140FC126Q0023, 2026

This is a full and open competition under NAICS code 562910. The U.S. Fish and Wildlife Service requires a contractor to delineate and characterize petroleum-contaminated soils and check for groundwater contamination in the land farm area, and remove marine lead battery parts and lead-contaminated soil from the beach at the Sheep Island Boat Maintenance Facility at Kodiak National Wildlife Refuge in Alaska. The Contractor shall provide a Site Characterization Report incorporating previous reports and develop a Corrective Action Completion Report (CACR) that discusses the cost and pros/cons of mitigating the site using active remediation, engineered barriers, institutional controls (Land Use Control Plan), or a combination of these methods if contamination remains on-site after completion of this work. The contractor shall provide a final recommendation based on this evaluation and the current data collected during this contract. Sheep Island is a remote island facility with absolutely no known amenities. All supplies and equipment necessary to perform this site survey/soil sampling must be transported to the site. The award will be based on the lowest price deemed fair and reasonable by the Government. The magnitude of construction is between $25,000 and $100,000. Offers are due by 9:00 AM EDT on June 18, 2026. https://sam.gov/workspace/contract/opp/edc8b48127f845d8b517b99301c3474d/view

REGION 2 ERRS RECOMPETE (COMBINE) [Market/Commercialization]

Fri, 5 Jun 2026 13:25:42 GMT

U.S. Environmental Protection Agency, Region 3 Contracting Office, Philadelphia, PA
Contract Opportunities on SAM.gov 68HE0326R0009, 2026

This is a total small business set-aside under NAICS code 562910. EPA seeks a contractor to support its ERRS contract. The purpose of the ERRS contract is to provide fast, responsive environmental cleanup services to the release, or threatened release, of hazardous substances/waste/pollutants and contaminants/materials and petroleum products/oil for the EPA Region 2, which has a geographic area comprised of New Jersey, New York, Puerto Rico, the US Virgin Islands, and eight Indian Nations. Environmental cleanup in response to natural and manmade disasters, terrorist activities, weapons of mass destruction, and chemical, biological, radiological, and nuclear incidents may also be required under this contract. A regional cross-over may be requested under this contract, under rare circumstances, international responses may be required. The award will be an IDIQ contract with a period of performance from January 27, 2027, through January 26, 2035. Offers are due by 10:00 AM EDT on July 20, 2026. https://sam.gov/workspace/contract/opp/26dd719fc2dc439ba8850eff4863f41f/view

ENHANCING HEAVY METAL REMOVAL USING NOVEL MEDIA SOLUTIONS [General News]

Tue, 19 May 2026 16:49:19 GMT

Boussoufa, I. | SMART Remediation, 29 January, Toronto, 44 slides, 2026

This presentation introduces advanced treatment methodologies for the removal of heavy metals, with a focus on arsenic, lead, uranium, and mercury. Capabilities of the Cleanit media, a novel iron-based media that efficiently removes lead and arsenic via adsorption and precipitation processes, are presented. The effectiveness of Cleanit-LC in removing toxic heavy metals to meet ultra-low discharge limits is demonstrated, showcasing its potential to significantly reduce environmental impact without altering pH levels, thus promoting cleaner industrial practices at a lower cost than specialized ion exchange resin. The presentation also covers ChemSorb ML, an innovative and versatile amendment for mercury removal. ChemSorb ML chemically binds various forms of mercury, including elemental, ionic, and methylmercury, achieving reductions of leachable mercury by > 99% and lowering concentrations to ppt levels, making it an effective solution for stringent compliance requirements. Case studies and performance data are provided to illustrate the practical applications and benefits of these media in real-world scenarios, underscoring their effectiveness in reducing operational costs and enhancing compliance with environmental regulations. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver_Calgary-2026-%E2%80%93-Imane-Boussoufa.pdf

INTEGRATING ANALYTICAL SOLUTIONS AND U-NET MODEL FOR PREDICTING GROUNDWATER CONTAMINANT PLUMES IN PUMP-AND-TREAT SYSTEMS [General News]

Tue, 19 May 2026 16:49:00 GMT

Song, X., I. Demirkanli, Z. Hou, X. Lin, M. Karanovic, M. Tonkin, D. Appriou, and R. Mackley.
Advances in Water Resources 202:105002(2025)

A novel approach that integrates analytical solutions for groundwater dynamics with the U-Net deep learning framework is introduced to predict groundwater contaminant plume migration under dynamic pumping conditions. By incorporating the Thiem equation into the input preprocessing, the U-Net model transforms sparse well data into a continuous spatial field that captures the hydraulic impacts of pumping activities. This integration enables the model to leverage both deep learning capabilities and classical physics-based groundwater theories, enhancing prediction accuracy and computational efficiency. For example, in 2D synthetic cases, integrating analytical solutions reduced the root mean squared error (RMSE) from 2.76 µg/L to 0.7 µg/L. In a complex 3D heterogeneous model of the Hanford Site's 200 West P&T facility, the model completed a 12-year simulation in just 600 ms on a single CPU core, achieving an accumulative RMSE of <1.6 µg/L, an improvement of over three orders of magnitude in simulation speed compared to a numerical model. Advancements support rapid evaluations of P&T optimization scenarios, enabling timely and effective decision-making for well placement and system management. Findings highlight the potential of advanced machine learning models to significantly enhance the efficiency and sustainability of groundwater remediation efforts, offering a novel application of the U-Net architecture in environmental science. https://www.sciencedirect.com/science/article/pii/S0309170825001162/pdfft?md5=85822b78bc54ffc8ae8397fa14a3632b&pid=1-s2.0-S0309170825001162-main.pdf

PRACTICAL FRAMEWORK FOR MANAGING PFAS IN WASTEWATER TREATMENT PLANTS: INTEGRATING PRE-TREATMENT AND IN-PLANT UPGRADES FOR SUSTAINABLE PFAS REDUCTION [General News]

Tue, 19 May 2026 16:48:43 GMT

Modiri, M., P.C. Sasi, L.S. Lee, and J. Norton. | Remediation 36(2):e70063(2026)

This perspective draws on recent full-scale monitoring studies, fluorine mass-balance analyses, and statistical evaluation of nationwide data sets to demonstrate that treatment processes compress influent PFAS variability into narrow effluent and biosolids distributions, erasing source fingerprints while redistributing rather than removing mass. The observations motivate a management approach centered on PFAS mass balance rather than end-of-pipe concentration control. A practical, eight-step decision framework is proposed that integrates three tiers of action: (1) source identification, classification of "low-strength," " medium-strength, " and " high-strength" influent streams, and deployment of high-leverage pre-treatment; (2) targeted in-plant controls focused on enrichment points such as foam, aerosols, and sidestreams, with polishing reserved for clean matrices where media exhaustion and residuals can be managed; and (3) residuals strategies that address PFAS in biosolids, concentrated liquids, and air-pollution-control byproducts through destruction or stabilization. The framework embeds conceptual PFAS flux diagrams, explicit consideration of regulatory and permitting constraints, and iterative triple bottom line evaluation to compare treatment trains based on net mass reduction, cross-media trade-offs, life-cycle cost, and community acceptability. The integrated model provides utilities with a structured pathway from diagnosis to implementation, helping avoid stranded investments in low-leverage technologies and supporting PFAS management strategies that are technically defensible, regulatorily viable, and aligned with long-term environmental and public health protection.

SYSTEMATIC SCREENING OF AQUEOUS FILM-FORMING FOAM (AFFF)-RELATED EMERGING PER- AND POLYFLUOROALKYL SUBSTANCES IN A FIREFIGHTING TRAINING SITE AND SURROUNDING MULTIMEDIA IN CHINA [Research]

Tue, 19 May 2026 16:48:27 GMT

Zhang, X., B. Qiao, Y. Zhang, T. Zhao, B. Fang, Y. Zhou, M. An, Y. Yao, H. Chen, and H. Sun.
Journal of Hazardous Materials 503:141244(2026)

Multimedia samples, including air, wastewater/river water, soil/sediments, herbaceous plants, and tree bark/leaves, were collected from a typical firefighting site in China. An integrated screening method tailored for AFFF-related PFAS efficiently identified PFAS across multiple media, comprehensively characterizing their contamination profiles in both atmospheric and terrestrial compartments. In total, 122 PFAS in 62 classes were detected. Notably, 18 AFFF-related PFAS were reported for the first time in environmental media, 10 of which were exclusively detectable through the diagnostic fragment-based screening strategy, underscoring the critical role of this strategy in uncovering structurally unknown PFAS. The highest PFAS diversity (113 compounds) was observed in herbaceous plant systems. Air samples contained 51 PFAS, dominated by anionic fluorotelomer-based PFAS and sulfonamide derivatives. A total of 37 and 38 PFAS were identified in tree bark and leaves, respectively, showing a 76% overlap with airborne PFAS profiles. Findings establish firefighting-derived PFAS as an important source of atmospheric contamination, highlighting a critical knowledge gap that warrants further investigation. https://www.sciencedirect.com/science/article/pii/S0304389426002220/pdfft?md5=fc16fcadb4771793c12b9294ad4e4277&pid=1-s2.0-S0304389426002220-main.pdf

PRELIMINARY EVALUATION OF IN SITU CHEMICAL OXIDATION EFFECTS ON SOIL CARBON DIOXIDE EMISSION IN A SOIL SLURRY SYSTEM [Research]

Tue, 19 May 2026 16:48:09 GMT

Wang, W.-J. and C. Liang. | Remediation 36(2):e70064(2026)

A study assessed the effects of ISCO on soil CO₂ emission rates and total bacterial counts by evaluating hydrogen peroxide (HP), sodium persulfate (SPS), and potassium permanganate (PM), alone and combined with various activation methods. CO₂ emission rates from the soil slurry system were measured using a closed static chamber method and expressed in CO₂/gds/h. Under stable conditions, soil CO₂ emission rates were ranked as follows: SPS groups (2.0~4.0) > PM group (1.9-3.1) > HP groups (0.6-1.8) ≈ original soil (0.4-1.0), while total soil bacterial counts (CFU/gds) ranked as: PM group (~107) > HP groups (~106) > original soil (~5.0 × 106) > SPS groups (~104-106). Most oxidant activation treatments led to higher CO₂ emission rates and soil bacterial counts, except under alkaline activation. Findings demonstrate the influence of different ISCO processes on soil CO2 emissions and offer a baseline for emission rates during ISCO remediation.

ACID TAR LAGOON REMEDIATION II: LONG-TERM LEACHING AND GEOCHEMISTRY OF STABILIZATION/SOLIDIFICATION MIX DESIGNS [Research]

Tue, 19 May 2026 16:47:46 GMT

Grubb, D.G., D.R.V. Berggren, E.K. Helbling, and B.K. Schroth.
Remediation 36(2):e70062(2026)

A U.S. project-based treatability study focused on the long-term leaching of benzene and metals from soil surrogates containing 20% (S2X) or 40% (S4X) acid tar by volume (where X denotes the testing phase) and their stabilization/solidification (S/S) mix designs (M2X or M4X) formed with grouts of powdered ladle slag (PLS), a 60/40 (w/w) blend of Type IL Portland Cement, and Grade 120 NewCem slag cement, and, in some mixes, bentonite. Long-term semi-dynamic leaching tests modified (M) for use with hydrocarbons (EPA 1315M) were performed on S/S-treated soil surrogates cured for 28 days. Percent leaching reductions (%LRs) were calculated by comparing quasi-steady-state benzene concentrations from EPA 1315M to the effective solubility of benzene in the untreated soil surrogates (318 mg/L for S22; 406 mg/L for S42). Minimum %LR values of 93.7% and 92.8% were observed for M22 mixes tested with and without 0.5% B, respectively. Parallel testing was conducted using freshly mixed (FM) M22 materials placed in a specialized extractor, where benzene leached into an overlying water cap beneath a continuously exchanged headspace over 91 days. The mass transfer rates from the FM tests compared very well with those from the EPA 1315M tests beginning around day 35, coinciding with the end of the startup period for the 28-day cured samples. Strong data agreement validated the accuracy and effectiveness of the polydimethylsiloxane liner used in the EPA 1315M test. The corresponding EPA 1315M leaching of most trace heavy metals was at or below their respective method detection limits for all leaching intervals for all mix designs. Cd, Se, and Zn showed similar performance with a few outliers. Ba concentrations were between 20 and 100 µg/L. Mo and V concentrations from the pH-dependent leaching (EPA 1313) test never exceeded 10 µg/L and were up to 100 times lower than those from the untreated soil surrogates at the same pH. After the 63-day EPA 1315M test, the unconfined compressive strength of the test samples was at least 689 kPa (100 lb/in²) greater than their 28-day values.

PFAS QUANTITATION WITH DIFFUSIVE GRADIENTS IN THIN-FILM PASSIVE SAMPLERS: CAPTURING TIME-WEIGHTED AVERAGE CONCENTRATIONS AROUND MAXIMUM CONTAMINANT LEVELS TO FACILITATE COMPLIANCE [Research]

Tue, 19 May 2026 16:47:21 GMT

Harris, B.J., S.D. Hodges, D.G. Wahman, L.M. Haupert, J.R. Chimka, and J.L. Fairey.
Water Research 300:125918(2026)

Diffusive gradients in thin-films (DGT) passive sampler gel layer diffusion coefficients (D_Gel) ± 95% confidence intervals (CIs) were determined for 32 PFAS using two-compartment diffusion cell tests analyzed with a non-steady-state finite difference model (FDM). This model was previously shown to produce D_Gel estimates with less error than traditional methods relying on a pseudo-steady-state flux assumption. For each PFAS, the FDM also determined the normalized weighted sum of squared errors (WSSE×n^-1), a goodness-of-fit measure. Eleven PFAS had adequate FDM fits (WSSE×n^-1< 0.03), and D_Gel ± 95% CIs decreased with increasing molecular weight (MW) from 7.1 to 5.1 (± 0.1-0.6) × 10^-6 cm²/s. For the other 21 PFAS, linear regression models (D_Gel vs. MW; R² ≥ 0.967) were used to estimate D_Gel ± 95% CIs from 3.4 to 7.6 (± 0.2-1.0) × 10^-6 cm²/s. Compared to their free water diffusivities, D_Gel values differed by a median of 6.5% and first and third quartiles of 4.5 and 8.7%, respectively. Error in D_Gel was propagated into C_DGT for 5-36-day lab-scale DGT deployments, in which C_DGT ± 95% CIs for 20-31 of the 32 PFAS were indistinguishable from grab samples (sign test; α = 0.05). DGTs accurately captured time-weighted average PFAS aqueous phase concentrations at ∼1, 10, 100, and 200 ng/L.

MXENE-BASED NANOCONFINED ION CHANNELS FOR ULTRATRACE DETECTION OF SHORT-CHAIN PER- AND POLYFLUOROALKYL SUBSTANCE TRIFLUOROMETHANESULFONIC ACID AND ITS ON-SITE APPLICATION [Research]

Tue, 19 May 2026 16:47:06 GMT

Xiao, J., X. Xiong, Y. Wu, L. Bu, J. Luo, and S. Zhou.
Environmental Science & Technology 60(12):9521-9529(2026)

A nanoconfined microenvironment was designed by intercalating 4-trifluoromethy-benzylammonium bromide into MXene (MX/CF3BZA) to construct a highly selective channel for the detection of trifluoromethanesulfonic acid (TFMS), a widespread and highly persistent member of the ultrashort-chain PFAS family. The resulting MX/CF3BZA-based ion-selective electrodes (ISEs) achieve remarkable performance, exhibiting an ultralow detection limit (1.2×10^-11 M), which is over 1×104-fold lower than that of conventional commercial ISEs, 17-fold enhancement in selectivity (Kij ∼ 7×10^-3), and near-Nernstian sensitivity of 56.37 mV/decade. Quartz crystal microbalance measurements directly corroborate this superior performance, showing a 6.4-fold stronger affinity of MX/CF3BZA for TFMS compared with pristine MXene. Density functional theory calculations reveal that the CF3BZA modification creates a unique nanoconfined environment that integrates synergistic F-F, electrostatic, and anion-π interactions, reducing the permeation energy barrier for TFMS by 16.71 kcal/mol. The ISE was integrated into a smartphone-based platform, demonstrating its practical application for onsite TFMS detection.

SEMI-QUANTITATIVE DIRECT-PUSH DATA CAN IMPROVE CONTAMINANT DELINEATION AND MASS DISCHARGE IN GROUNDWATER [Demonstrations]

Tue, 19 May 2026 16:46:43 GMT

Bollingtoft, A., W. Nowak, P.L. Bjerg, G. Lilbæk, A.G. Christensen, and M. Troldborg.
Groundwater 64(2):189-201(2026)

This study introduces a probabilistic censoring method that enhances geostatistical interpolation by incorporating comparably inexpensive, high-resolution, but semi-quantitative data collected from direct push-probes in the subsurface. The method converts halogen-specific detector signals into binary presence-absence indicators, which are interpolated using indicator kriging to generate a probability field of contaminant distribution. The probability field is then used to censor a spatial concentration field derived from traditional groundwater sampling, retaining interpolated concentration values only in areas where contamination is likely. The method was applied to a site contaminated with chlorinated solvents using two datasets with different sampling densities. Results using the new method show that plume fringes became more clearly defined and the total area with low concentrations (<10 µg/L) increased by 41-85%. CMD estimates were reduced by 13-18%, while relative uncertainty remained largely unchanged. The method integrates with traditional interpolation methods, and the censoring workflow can be applied to other forms of direct-push data. As such, the framework offers a useful method for incorporating semi-quantitative field measurements into concentration interpolation and CMD estimation at contaminated sites.

SILICONE-FOAM PASSIVE AIR SAMPLERS FOR COMBINED TARGET AND NONTARGET CHEMICAL PROFILING AND TOXICITY ASSESSMENT OF AIRBORNE EXPOSOMES [Demonstrations]

Tue, 19 May 2026 16:46:28 GMT

Sunyer-Caldu, A., H. Xie, B. Bonnefille, F. Raptopoulou, E. Pesquet, M.B. Rian, D. Schlesinger, M. Norman, Y. June Jeon, B. Kim, S.-B. Lee, J. Eun Lee, J. Froment, S. Papazian, and J.W. Martin. Environmental Science & Technology 60(7):5628-5644(2026)

Polydimethylsiloxane (PDMS) foam or silicone foam was previously shown to be capable of being synthesized for passive air sampling, enabling simple and cost-effective nontarget chemical profiling of indoor air. In this study, expanded applications, indoors and outdoors, were demonstrated with commercial PDMS-foam, including for wide-scope target analysis of >220 priority substances by quantitative LC-HRMS and GC-HRMS, microscopic characterization and nontarget profiling of accumulated fine particles, and effect-guided discovery of harmful substances, combining toxicological data with nontarget analysis in silico. Median method quantification limits were 0.12 ng/mL, 90% of target analytes had absolute recoveries between 70 and 130%, and hazardous substances were discovered, including ethylene glycols, insecticides, and UV filters. Microscopy revealed the accumulation of abundant fine particles, and the automated characterization of the fluorescent fraction revealed that most were <4 µm. Extracts from outdoor samples reduced human lung cell viability, and multivariate modeling flagged families of potentially toxic substances in a virtual effect-directed analysis. PDMS-foam disks require field calibration to determine their linear sampling rate(s), but current results and applications establish PDMS-foam as a multimodal passive sampler, enabling integrated chemical quantitation, toxicological analysis, and molecular discovery in air.

BIOASH-BASED STABILIZATION/SOLIDIFICATION FOR HEAVY METAL(OID) SOIL REMEDIATION: A CASE STUDY IN NORTHERN SWEDEN [Demonstrations]

Tue, 19 May 2026 16:45:56 GMT

Khasevani, S.G., I. Carabante, J. Bjuhr, and L. Andreas.
Materials 19(4):790(2026

A bioash-cement composite binder was evaluated as a low-cement stabilization material for metal-contaminated soils, with emphasis on mechanical performance and long-term leaching behavior under field conditions. Two fine soil fractions from the Nasudden area (Skelleftea, Sweden), classified as hazardous (HS) and non-hazardous (NHS), were first treated in lab trials to optimize binder composition. An optimum formulation containing 35 wt.% bioash and 5 wt.% cement (dry basis, relative to soil) improved unconfined compressive strength (UCS) to 696 kPa (HS) and 479 kPa (NHS) after 28 days and reduced Zn, Cd, Pb, and Co leaching. Arsenic immobilization improved in HS but decreased in NHS, while Cu and Ni leaching increased, consistent with elevated pH and dissolved organic carbon promoting soluble complexation. The optimized binder was then applied to a pilot soil and validated at pilot scale by treating 100 tonnes of soil and constructing a 2 m high noise barrier. Parallel lab tests on the pilot soil yielded UCS values of 1000 kPa and confirmed effective Zn and Cd retention, with generally good Pb stabilization, while As remained the most mobile element across soil types. Two-year field monitoring showed decreasing leachate concentrations of As, Cu, Ni, Pb, and Zn over time; field samples exhibited improved Cu and Ni retention compared with lab results, suggesting progressive aging effects such as carbonation and mineral transformations. Results demonstrate that bioash-cement binders can produce mechanically stable treated materials suitable for low-load applications while reducing cement demand; however, performance is strongly controlled by soil-specific chemistry and field execution (mixing and compaction), and further binder optimization is required to address arsenic mobility. https://www.mdpi.com/1996-1944/19/4/790

DETERMINING THE EFFECTIVENESS OF FREQUENCY DOMAIN ELECTROMAGNETIC AND GROUND PENETRATING RADAR SURVEYING TECHNIQUES IN DETERMINING THE EXTENTS OF BURIED WASTE IN SMALL TRENCH-AND-FILL WASTE DISPOSAL SITES [Demonstrations]

Tue, 19 May 2026 16:45:37 GMT

McKay, G. | RemTech East, 8-10 April, Ottawa, Canada, 13 slides, 2026

A study aimed to delineate buried waste at trench-and-fill style landfills in Northern Ontario using electromagnetics (EM) and ground-penetrating radar (GPR). An EM survey was conducted at each site using an EM-31 MK2, and a GPR survey was conducted using a Noggin 250 SmartCart with a DVL-500 data logger. The EM31-MK2 accurately determined the lateral extents of buried waste compared to the results of the test-pitting program. The accurate delineation of buried waste, combined with the maneuverability and ease-of-use of the EM-31 MK2, makes it an ideal tool for lateral waste delineation in small landfilling sites. The Noggin-250 SmartCart was able to delineate the edges and top of buried waste in some instances, but not consistently. The Noggin-250 SmartCart was also difficult to use over rugged terrain. Download presentation at https://esaa.org/wp-content/uploads/2026/05/RemtechPresentation-GregMcKay-Gregory-McKay.pptx

WYCKOFF/EAGLE HARBOR SUPERFUND SITE BAINBRIDGE ISLAND, WASHINGTON [Cleanup News]

Tue, 19 May 2026 16:44:44 GMT

Migdal, W. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 16 slides, 2026

The Wyckoff/Eagle Harbor Superfund site is a complex remediation project involving historical creosote contamination. This project included demolishing an existing treatment system, abandoning 69 monitoring and extraction wells, installing 16 new monitoring and extraction wells and one deep fresh water well, excavating 9,000 bank yd³ of contaminated soil, removing 5,760 ft² of steel sheet pile, and managing, transporting, and disposing of construction debris and hazardous waste. The project also involved demolishing two small buildings, installing eight portable extraction well pump skids, upgrading the existing groundwater treatment plant, updating electrical controls, installing wireless controls and transducers, and excavating 600 linear ft of utility trenches. Remote technology, including a site camera, was installed at the site to allow real-time viewing of the site activities and to provide digital archives of activities performed. Key lessons learned during the project:

A dedicated field and management staff is critical for large complex projects.

Establish effective communication channels.

Establish transparency and trust with all stakeholders.

Project collaboration leads to innovation.

Shared values/vision are critical to set the tone for the project.

https://mediacdn.guidebook.com/upload/213718/xDJRrAHD9ApPUn9gpDbRPlxpYu6Te18bjMeX.pdf

BEDROCK INJECTIONS – A SUCCESS STORY BUILT ON CHAPTERS OF FAILURE [Cleanup News]

Tue, 19 May 2026 16:44:29 GMT

Lingwood, S. | RemTech East, 8-10 April, Ottawa, Canada, 20 slides, 2026

This presentation outlines a case study of remedial injection challenges and ultimate success in shale bedrock beneath a large commercial mall in southern Ontario, Canada, impacted by commingled CVOC plumes from historical dry cleaning operations affecting both overburden and a complex sequence of weathered, competent, and fractured shale. The project narrative follows an iterative path of initial program design, geophysical testing, injection failures, redesigns, and mounting frustration, followed by adaptation, innovation, and collaboration that ultimately led to a successful remedial strategy. Download presentation at https://esaa.org/wp-content/uploads/2026/05/RemTechEast-BedrockInj.Slingwood.Apr2026-Samuel-Lingwood-1.pptx

CONVERTING PFAS-IMPACTED LANDFILL LEACHATE WASTE FROM A LIQUID TO A SOLID: USING FULL-SCALE FOAM FRACTIONATION AND MEDIA SUPERLOADING TO MINIMIZE WASTE AND REDUCE RISK [Cleanup News]

Tue, 19 May 2026 16:44:09 GMT

Newman, P. | RemTech East, 8-10 April, Ottawa, Canada, 17 slides, 2026

A combined system of foam fractionation on landfill leachate and Superloading adsorptive media treatment on the concentrated liquid waste to convert the foam fractionate liquid to a solid waste was designed to assist a landfill in the cost-effective treatment of PFAS. The foam fractionation and Superloading test design progressed from the pilot scale to a full-scale design and installation, with 1.5 years of operational data. The system operates with lead-lag Foam X-3000 foam fractionators, which were designed and implemented for this site. Treatment goals include the removal of 75% of PFAS mass, with the proportion of PFAS being <45% short chain. Multiple chemical reagents were evaluated and optimized to manage solids formation and achieve the PFAS treatment goals. Under continuous operation, the system treats ~100 gals/min. The resulting foamate is treated in successive adsorptive media beds and then re-blended into the foam fractionation system influent. The adsorptive media are returned with sequestered PFAS to the landfill. Operating the foam fractionation system continuously resulted in the implementation of long-term chemical dosing strategies to maintain smooth operations in the fractionators. Periodic changes in the leachate composition were managed while maintaining performance. The foamate Superloading process resulted in up to an additional 500-fold of waste concentration in a solid media format, with changeouts timed to coincide with preventing re-blended foamate from impacting foam fractionation treatment objectives. Overall, a waste concentration factor of ~1000 to 2000-fold was achieved at the landfill. The landfill operator maintained their disposal outlet for their leachate by implementing this system. The presentation includes operational lessons learned and performance data demonstrating the removal of PFAS in both primary system components. Download presentation at https://esaa.org/wp-content/uploads/2026/05/2026-RemTech-East-Newman-Foam-Fractionation-Final-Paul-Newman.pptx

A CASE STUDY: THE USE OF CHEMICAL AND BIOLOGICAL TECHNIQUES TO REMEDIATE A CVOC PLUME AT A FORMER LANDFILL [Cleanup News]

Tue, 19 May 2026 16:43:24 GMT

Davidson, M.A. | RemTech East, 8-10 April, Ottawa, Canada, 26 slides, 2026

This case study explores the importance of high-resolution delineation of cVOC contamination in groundwater in a leaky confined aquifer with silt lenses; the performance of in situ injections and delivery of both chemical and biological remedial agents into this aquifer to treat the cVOC plume hot spots; and the supplementation of a Dhc population to treat the groundwater cVOC plume at large. Modeling a high-resolution spatial-temporal dataset in three-dimensions showed the importance of contaminant delineation at the start of the remedial process. The case study demonstrated that in situ chemical and biological remedial agents can effectively treat cVOC source zones, while in situ injections of biological treatments alone can be a more cost-effective means of treating the tail end of the cVOC plume. Download presentation at https://esaa.org/wp-content/uploads/2026/05/Davidson_Mitchell_RemTechE_2026-Mitchell-Davidson.pptx

FY26 ENVIRONMENTAL REMEDIATION MATOC [Market/Commercialization]

Tue, 19 May 2026 16:43:11 GMT

US Army Corps of Engineers Engineer Division North Atlantic
Contract Opportunities on SAM.gov W912GB26RA021, 2026

The U.S. Army Corps of Engineers, Europe District, requests proposals from qualified firms interested in performing work in support of environmental surveillance and remediation services under NAICS code 562910. Under this planned contract, the Contractor shall provide all labor, supervision, transportation, supplies, vehicles, tools, materials, equipment, and incidental services required to execute and document results of environmental remediation projects at DoD facilities. The type of work to be performed under this contract shall include but is not limited to: (1) Surveys, Assessments, and Plans, (2) Studies and Reports, (3) In-situ/Ex-situ Cleanup, and (4) Other Mitigation and Environmental Services. The proposed contract may be used to support the U.S. Army Europe Installations and/or other U. S. Government Agency requirements in Germany and BENELUX. Small and Disadvantaged Business requirements are waived for this project due to its location being OCONUS. The contract will consist of a five-year base period. The contemplated value is $45,000,000.00 to be shared across the contract pool. Offers are due by 5:00 AM EST on June 8, 2026. https://sam.gov/workspace/contract/opp/7aaedf679f9e4af3985594cd29f03b5a/view

F--NAVAJO AREA - ABANDONED MINES RESPONSE AND CONSTRUCTION SERVICES [Market/Commercialization]

Tue, 19 May 2026 16:42:56 GMT

Environmental Protection Agency, Region 9
Contract Opportunities on SAM.gov 68HE0926R0006, 2026

The purpose of this Pre-Solicitation Notice Amendment is to incorporate the updated Industry Day Flyer. The primary hazardous substance on all the sites referenced in the requirement's Statement of Work (SOW) is radiological mine and mine-related waste; therefore, a significant knowledge base of radiological material handling, environmental data interpretation, and data collection will be required to perform the activities within this SOW. The Contractor shall provide clean-up, response, and construction services to the U.S. EPA, primarily at former uranium mining-related sites located within or nearby the Navajo Nation and the Grants Mining District in New Mexico in U.S. EPA Regions 6 and 9. EPA expects to make an award for this requirement by September 1, 2026. A pre-proposal Industry Day/Conference amongst the U.S. EPA and Potential Offerors is anticipated to occur approximately 1 week after the Request For Proposals is posted on FEDCONNECT. Conference will be held virtually via Microsoft Teams and wll include site walks at select mines. Attendees will have the opportunity to discuss technical components and opportunities related to upcoming 5-year AMRCS II requirement. https://sam.gov/workspace/contract/opp/5bf7c3b84524453db88b15e5c5ff341c/view

PRESOLICITATION NOTICE; FA890326R0007 - ENVIRONMENTAL CONSTRUCTION OPTIMIZATION SERVICES (ECOS) (PRESOL) [Market/Commercialization]

Tue, 19 May 2026 16:42:26 GMT

U.S. Department of the Air Force, Air Force Materiel Command, AF Installation and Missions Support Center, JBSA Lackland, TX
Contract Opportunities on SAM.gov FA890326R0007A, 2026

When this solicitation is released, it will be competed as a total small business set-aside under NAICS code 562910. The 772nd Enterprise Sourcing Squadron PKB Flight intends to issue a Request for Proposal (RFP) for the Environmental Construction Optimization Services (ECOS) Multiple Award Task Order Contract (MATOC) / Indefinite-Delivery/Indefinite-Quantity (IDIQ) contract. This requirement is for comprehensive environmental services to support mission requirements. The broad scope of work encompasses environmental planning, investigation, remediation, construction, and compliance activities. The Government anticipates awarding multiple contracts under this solicitation. The total ceiling for this IDIQ contract will be $3.5 billion with a 5-year base period and one 3-year option period. There is no solicitation at this time. https://sam.gov/workspace/contract/opp/8a0862907b754cd2b1d07757f362918d/view

CURRENT KNOWLEDGE ON PHYTOREMEDIATION POTENTIAL OF INDUSTRIAL HEMP (CANNABIS SATIVA L.) FOR PFAS AND HEAVY METAL CONTAMINATED SOILS [General News]

Thu, 7 May 2026 14:00:53 GMT

Ansari, O. and L. De Prato. | Remediation 36(2):e70059(2026)

This review compiles current research on the phytoremediation potential of industrial hemp (Cannabis sativa L.) for heavy metals, including arsenic, aluminum, mercury, copper, lead, cadmium, nickel, and zinc, as well as PFAS. Interdisciplinary studies were conducted across greenhouse, field, hydroponic, and amendment-based experiments. Findings indicate that hemp exhibits strong tolerance and accumulation capacity for cadmium, lead, and arsenic, with metal uptake primarily concentrated in roots. Cultivar differences significantly influence both uptake efficiency and biomass yield. PFAS uptake is selective, with higher bioconcentration observed for short-chain and carboxylic acid compounds, although overall soil PFAS removal remains low to moderate. Remediation efficacy is modulated by soil properties, biosolid amendments, and microbial symbioses, which enhance PFAS bioavailability and plant tolerance. Comparative assessments reported in the literature suggest that hemp's rapid biomass production and adaptability may offer advantages over other phytoremediation species. However, limitations in PFAS degradation and ecological risks, such as PFAS accumulation in pollen, persist. Integration of soil amendments and microbial inoculants shows potential to enhance hemp growth rates and PFAS tolerance; however, further testing and field validation are required. The review underscores hemp's potential as a sustainable phytoremediation agent and a component of integrated PFAS remediation strategies, while highlighting the need for standardized protocols and risk assessments to ensure environmental safety and practical scalability. https://onlinelibrary.wiley.com/doi/epdf/10.1002/rem.70059

A RECENT OVERVIEW OF PHOTO ELECTRO CATALYTIC MATERIALS MECHANISTIC INSIGHTS TOWARDS PFASS DEGRADATION: BY-PRODUCTS DETERMINATION AND AI/ML IMPLICATIONS [General News]

Thu, 7 May 2026 13:59:36 GMT

Penke, Y.K., P. Chamoli, and H.-M. Lo. Chemosphere 397:144852(2026)

This review examines the electrochemical and photocatalytic activities of various materials/composites that degrade PFAS. Technical observations are primarily referenced from recent literature published between 2020 and 2025. Iron and titanium species have shown better remediation abilities, which was reported in the majority of publications. Iron systems have shown better parameters for electrochemical activities (electrooxidation/reduction), whereas titanium suboxides and bismuth sheets are better related to the photoelectrochemical activity. Other 3D metal systems like Co, Ni, and boron-doped diamond, carbon structures (activated carbon, carbon sphere, and aerogel) are also detailed with PFOA and PFOS treatment. In understanding the degradation mechanism, the radical species activity has densely dominated the process with the support of radical oxygen/sulphur species and charge transfers. Radical species activity, dissolved oxygen influence, and direct electron transfer mechanism are provided to understand the heterogeneous catalytic reactions and redox materials chemistry. Decarboxylation and hydro-defluorination mechanisms are explained with a set of findings based on the catalyst and compound chain length. Determination of degradation byproducts and intermediates utilizing different state-of-the-art spectroscopy tools is detailed to support the issue related to the secondary contamination in various remediation sites and the necessary field studies findings. Implications of AI/ML towards efficient handling of the various PFAS treatment and management technologies are discussed briefly.

WEB-BASED TOOLS FOR DATA-INFORMED REMEDY OPTIMIZATION: SOFTWARE THEORY AND USER GUIDE [General News]

Thu, 7 May 2026 13:59:20 GMT

Song, X., F. Lopez Jr., M. Corney, P. Tran, Y.S. Afzal, T.E. Joppich, S.N. Baur, H. Luu, R. Osman, C.D. Johnson, and I. Demirkanli. PNNL Report PNNL-38413; DVZ-RPT-121, 50 pp, 2025

This report documents the development and application of two web-based decision-support tools for PTOLEMY (Pump-and-Treat Optimized Location Evaluation to Maximize Yields) and OPTIMA (Optimization for Pump-and-Treat Implementation, Management, & Assessment). These tools enhance remedy design and management by leveraging advanced computational methods (deep learning and multi-objective optimization) within a user-friendly platform. By integrating data-driven models with established hydrogeological knowledge, PTOLEMY and OPTIMA enable more efficient evaluation of well placement and operational strategies, helping site managers balance multiple remediation objectives under complex conditions. Both tools are implemented as modules within the Suite Of Comprehensive Rapid Analysis Tools for Environmental Sites (SOCRATES) web platform, which provides data access, visualization, and analytics to support remedy optimization across sites. Both PTOLEMY and OPTIMA are intended as decision support tools to guide and streamline P&T design processes, not as replacements for site-specific modeling or regulatory decision-making requirements. They provide preliminary analyses that must ultimately be confirmed with high-fidelity models and engineering review. The tools are designed for transparency and traceability; they draw from established data sources and allow users to export maps, data tables, and configurations for documentation. By accelerating the exploration of "what-if" scenarios and narrowing down options, PTOLEMY and OPTIMA support more informed, timely, and cost-effective decision-making in P&T remedy management. https://www.osti.gov/servlets/purl/3001001

ACID TAR LAGOON REMEDIATION I: BASELINE GEO-ENVIRONMENTAL CHARACTERIZATION AND PRELIMINARY STABILIZATION/SOLIDIFICATION MIX DESIGNS [Research]

Thu, 7 May 2026 13:59:06 GMT

Grubb, D.G., D.R.V. Berggren, and E.K. Helbling. Remediation 36(2):e70061(2026)

A treatability study is presented that describes the baseline geo-environmental characterization and pH buffering of soil surrogates containing 20% (S2X) or 40% (S4X) acid tar by volume (where X denotes testing phase) and various stabilization/solidification (S/S) mix designs using powdered ladle slag (PLS), a 60/40 (w/w) blend of Type IL Portland Cement (PC) and Grade 120 NewCem (NC) slag cement, and bentonite (B) for some mixes. The soil surrogates reflected the expected in situ S/S (ISS) profile comprising an ISS rig working platform, residual tar, bottom lagoon liner materials, and shallow subsurface soils after the bulk tars are excavated for incineration. The total benzene content of the S41, S42, and S22 soil surrogates averaged 16,300, 24,000, and 10,568 mg/kg, respectively, with corresponding sulfur contents of 28,350, 93,500, and 43,500 mg/kg and pH values typically less than 0.5. EPA 1313 testing on the S41/S42 soil surrogates tracked the leaching of EPA target analyte list metals over a range of pH and also indicated that it took about three equivalents of base addition to maintain pH conditions above 8 to ensure the long-term stability of the ISS mixes. EPA 1316 M leaching of VOCs indicated that the S41, S42, and S22 media were characterized by benzene effective concentrations of 497, 406, and 318 mg/L, respectively. The S41 and S42 surrogates were extremely challenging to solidify, requiring 5 wt% PLS + 35 wt% PC/NC to exceed the relatively modest unconfined compressive strength (UCS) target of 276 kPa (40 lb/in²). Regardless of UCS, most ISS mixes met the permeability criterion of less than 1×10^-6 cm/s. The minimum ISS reagent dose satisfying the UCS, K, and residual pH buffer capacity (3 meq/g) targets for 28-day cured mix designs for the S22 soil surrogate was 5 wt% PLS + 30 wt% PC/NC + 0.5 wt% B. This was the minimum reagent dose proposed for long-term leaching and field pilot testing.

HUMAN IN VITRO METABOLISM OF AN ENVIRONMENTAL MIXTURE OF POLYCYCLIC AROMATIC HYDROCARBONS (PAH) FOUND AT THE PORTLAND HARBOR SUPERFUND SITE [Research]

Thu, 7 May 2026 13:58:38 GMT

Gaither, K.A., K. Tyrrell, W. Garcia, K.A. Anderson, and J.N. Smith.
Toxicology Letters 412:172-181(2025)

A study aimed to measure human metabolism rates of Supermix-10, the ten most abundant PAHs found at the Portland Harbor Superfund site, to support the development of human pharmacokinetic models. Individual PAHs were incubated from Supermix-10 in pooled human liver microsomes and quantified parent PAH disappearance using high-performance liquid chromatography with UV and fluorescent detection. To assess the potential of mixture interactions, the metabolism of all 10 compounds was measured in an equimolar mixture, and the rates of parent disappearance were compared to those observed for individual PAHs. All Supermix-10 PAHs demonstrated rapid parent compound disappearance in human hepatic microsomes. PAHs are grouped into high metabolism rates and capacity (2-methylnaphthalene, acenaphthylene, fluorene, naphthalene), high-affinity metabolism that rapidly achieves low-level saturation (benzo[a]anthracene, chrysene), and moderate metabolism rates and capacity (fluoranthene, pyrene, retene, phenanthrene). Smaller PAHs exhibited faster metabolism, and higher metabolism rates correlated inversely with molecular weight. When incubated in an equimolar mixture, Supermix-10 demonstrated significantly slower metabolism (47-89 %) compared to the metabolism of individual PAHs at the same concentration. Findings enhance understanding of PAH metabolism in humans and demonstrate significant mixture interactions under the conditions tested. They also offer insights into the metabolic behavior of Supermix-10 and provide critical metabolism rate data to support the development of physiological based pharmacokinetic models.

MEASURING FLUOROTELOMER ALCOHOLS BY THERMAL DESORPTION-GAS CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY: INTERLABORATORY STUDY RESULTS [Research]

Thu, 7 May 2026 13:58:23 GMT

Eichler, C., H. Calder, B. Chandramouli, M. Curtis, H. Hayes, B. Kim, R. Marfil-Vega, C. Mejías, L. Miles, A. Owens, J. Stuff, K. Thaxton, J. Vandenberg, N. Watson, D. Wevill, J. Whitecavage, and X. Liu. | Journal of Chromatography A 1769:466725(2026)

An international interlaboratory study (ILS) was conducted with nine labs to evaluate the precision of ASTM International Standard Test Method D8591 to measure fluorotelomer alcohols (FTOHs). The test method specifies the analysis of four FTOHs (4:2, 6:2, 8:2, and 10:2 FTOH) collected on PFAS-specific thermal desorption tubes by gas chromatography coupled with tandem mass spectrometry. During the ILS, participating labs were instructed to use the test method to analyze three samples (A, B, and C) three times. Each sample contained the target FTOHs at defined concentrations unknown to the labs. The results from seven laboratories show that the relative reproducibility standard deviation (RSD_R) of the method ranges from 14% to 26%, and the relative repeatability standard deviation (RSD_r>/sub>) ranges from 4.6% to 11%, with RSDs decreasing with decreasing volatility of the FTOHs. Bias ranged from -13% to 6.0% and was generally larger and negative for less volatile FTOHs. The test method, in conjunction with the precision statistics from this ILS, will provide a reliable, defendable method that can be used in the context of studying PFAS sources, transport, and human exposure.

SUSTAINABILITY ASSESSMENT OF ALTERNATIVE METHODS FOR DESTRUCTION OF PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS) IN WATER [Research]

Thu, 7 May 2026 13:58:07 GMT

Mohamed, M.S. and K.R. Reddy. | Remediation 36(2):e70054(2026)

Research aimed to evaluate the sustainability of three methods for destroying PFAS: incineration, electrochemical oxidation (EO), and ultraviolet advanced oxidation processes (UVAOP). The triple bottom line sustainability framework was used to evaluate the environmental, economic, and social aspects of the destruction methods. Environmental consequences were evaluated through a life cycle assessment implemented in SimaPro. Economic sustainability was assessed by analyzing direct and indirect costs. Social implications were evaluated using the Social Sustainability Evaluation Matrix. Furthermore, the Integrated Value Model for Sustainability Assessment was used to integrate the results of environmental, economic, and social sustainability assessments. Results show that EO is the most sustainable method with a sustainability index (SI) of 0.90, followed by UVAOP (SI = 0.48), whereas incineration is the least sustainable (SI = 0.29), under balanced weighting criteria. https://onlinelibrary.wiley.com/doi/epdf/10.1002/rem.70054

INITIAL UNCERTAINTY ANALYSIS OF CARBON TETRACHLORIDE CONTAMINATION AND REMEDIATION IN THE RINGOLD A AND LOWER MUD UNITS AT THE CENTRAL PLATEAU [Research]

Thu, 7 May 2026 13:57:51 GMT

He, X., M. Rockhold, and X. Song. PNNL Report PNNL-38406, 16 pp, 2025

The long-term effectiveness of groundwater cleanup at the Hanford Site Central Plateau depends on predictive models that can capture key uncertainties in contaminant fate and transport. Carbon tetrachloride (CCl_₄) presents challenges due to variability in degradation rates, uncertainty in initial plume distribution, and subsurface heterogeneity, which directly influence plume persistence, migration pathways, and remedy performance. A large-scale Monte Carlo analysis was conducted using the Plateau to River (P2R) model framework that parameterized degradation rate, initial plume distribution, and hydraulic conductivity. Degradation was represented as a first-order process, with half-lives ranging from 70 to 700 years. Initial plume distributions were created using a geostatistical simulation method (sgsim), which generates many equally plausible versions of how contaminants might be distributed underground. From this, 100 different scenarios were mapped onto the P2R grid. Variability in hydraulic conductivity was represented similarly, with 100 scenarios each for the Ringold Lower Mud and Ringold A units (layers 6 and 7), based on fitted exponential variograms and conditioned to well data. In total, more than 1,000 realizations were simulated to assess plume behavior under uncertainty. The analysis highlights that uncertainty in degradation rate and initial plume configuration are the primary drivers of variability in plume predictions, while conductivity heterogeneity plays a limited role. Findings underscore the need for improved site-specific data on degradation processes and source characterization to enhance the reliability of long-term performance assessments and to better inform remedial decision-making. https://www.osti.gov/servlets/purl/3000283

BIOASH-BASED STABILIZATION/SOLIDIFICATION FOR HEAVY METAL(OID) SOIL REMEDIATION: A CASE STUDY IN NORTHERN SWEDEN [Demonstrations]

Thu, 7 May 2026 13:57:35 GMT

Khasevani, S.G., I. Carabante, J. Bjuhr, and L. Andreas.
Materials 19(4):790(2026)

A pilot study evaluated bioash-cement composite binder as a low-cement stabilization material for metal-contaminated soils, with an emphasis on mechanical performance and long-term leaching behavior under field conditions. Two fine soil fractions from the Nasudden area, classified as hazardous (HS) and non-hazardous (NHS), were treated in lab trials to optimize binder composition. An optimum formulation containing 35 wt.% bioash and 5 wt.% cement (dry basis, relative to soil) improved unconfined compressive strength (UCS) to 696 kPa (HS) and 479 kPa (NHS) after 28 days and reduced leaching of Zn, Cd, Pb, and Co. Arsenic immobilization improved in HS but decreased in NHS, while Cu and Ni leaching increased, consistent with elevated pH and dissolved organic carbon promoting soluble complexation. The optimized binder was then applied to a third pilot soil and validated at pilot scale by treating 100 tonnes of soil and constructing a 2 m high noise barrier. Parallel lab tests on the pilot soil yielded UCS values of 1000 kPa and confirmed effective retention of Zn and Cd, with generally good Pb stabilization, whereas As remained the most mobile element across soil types. Two-year field monitoring showed decreasing leachate concentrations of As, Cu, Ni, Pb, and Zn over time, and field samples exhibited improved Cu and Ni retention compared with lab results, suggesting progressive aging effects such as carbonation and mineral transformations. Results demonstrate that bioash-cement binders can produce mechanically stable treated materials suitable for low-load applications while reducing cement demand; however, performance is strongly controlled by soil-specific chemistry (notably DOC) and field execution (mixing and compaction), and further binder optimization is required to address arsenic mobility. https://www.mdpi.com/1996-1944/19/4/790

LONG-TERM PERFORMANCE OF PASSIVE VOLATILE ORGANIC COMPOUNDS (VOCS) SAMPLERS FOR INDOOR AIR [Demonstrations]

Thu, 7 May 2026 13:57:19 GMT

Zimmerman, J., B. Schumacher, C. Lutes, B. Cosky, and H. Hayes.
Environments 12(8):267(2025)

The first phase of this study evaluated the performance of Radiello® charcoal-based, solvent-extracted passive samplers over exposure periods ranging from one week to one year in a test house with known vapor intrusion (VI). Chloroform %Bias values exceeded the ±30% acceptance criterion after four weeks of exposure. Benzene, hexane, and TCE concentrations were within the acceptance criterion for up to three months. Toluene and PCE demonstrated uniform uptake rates over one year. In the second phase of this study, testing of the longer exposure times of six months and one year was evaluated with three additional passive samplers: Waterloo Membrane Sampler™ (WMS™), SKC 575 with secondary diffusive cover, and Radiello 130 passive samplers with yellow diffusive bodies. The SKC 575 and Radiello 130 passive samplers produced acceptable results (%Bias ≤ 30%) over the six-month exposure period, while the WMS sampler results favored petroleum hydrocarbon more than chlorinated solvent uptake. After the one-year exposure period, the passive sampler performances were acceptable under specific conditions for this study. Results suggest that all three samplers can produce acceptable results over exposure time periods beyond 30 days and up to a year for some compounds. This article is Open Access at https://www.mdpi.com/2076-3298/12/8/267

TREATABILITY STUDY TO EVALUATE BIOREMEDIATION OF TRICHLOROETHENE AT SITE K, FORMER TWIN CITIES ARMY AMMUNITION PLANT, ARDEN HILLS, MINNESOTA, 2020-22 [Demonstrations]

Thu, 7 May 2026 13:56:57 GMT

USGS, Scientific Investigations Report 2025-5113, 104 pp, 2025

Lab and field treatability tests were completed to evaluate the potential application of anaerobic bioremediation for a shallow TCE-contaminated groundwater plume in a perched alluvial aquifer at Site K, former Twin Cities Army Ammunition Plant. The plume extends beneath Building 103, where soil excavations left some deeper contaminated soil in place within the TCE source area. The report describes the study, including the pre-design site characterization to assist in formulating the bioremediation approach, lab experiments to support the design of the pilot test, and implementation and one-year performance monitoring results. The pilot test utilized three separate test plots, each about 30-ft wide and 60-ft long: plots GS1 and GS2 in the source area of the plume and plot GS3 in the downgradient area of the plume near the excavation trench. Each test plot had one injection well, one monitoring well upgradient from the injection point, and 12 surrounding monitoring wells in a grid to capture variable groundwater flow directions. Performance monitoring included hydrologic measurements and analyses of cVOCs, redox-sensitive constituents, dissolved organic carbon, bromide, volatile fatty acids, compound-specific carbon isotopes, and microbial communities. Data collected during the tests showed that enhanced, complete reductive dechlorination of cVOCs in the groundwater was achieved in the GS1 and GS3 plots. In contrast, evidence of the distribution of the injected amendments and subsequent biodegradation was limited in GS2, which was in an area of more heterogeneous soil lithology and low water table elevations. The pilot tests showed that the relatively low hydraulic head gradients and temporal changes in groundwater flow directions in the shallow aquifer would add complexity to a full-scale bioremediation effort. The radius of influence (ROI) at GS1 and GS3 was close to the design ROI of 15 ft. The estimated ROI at GS2 was about four times the design ROI, but it may be less reliable at this location due to groundwater flow direction. In addition, the low temperatures following WBC-2 injection, combined with the low hydraulic head gradients, were probably major factors in the delay observed before the onset of enhanced biodegradation following injection of the culture. Additional test injections could be beneficial to optimize the timing of donor and culture injections with the variable temperatures and hydraulic head in the shallow aquifer. https://pubs.usgs.gov/sir/2025/5113/sir20255113.pdf

GROUNDWATER RESTORATION AND LONG-TERM STEWARDSHIP AT A FORMER SMELTER [Cleanup News]

Thu, 7 May 2026 13:56:36 GMT

Hay, M. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 15 slides, 2026

Remedial design and construction activities were completed for a former lead and copper smelter in El Paso, Texas. Groundwater across a portion of the site is impacted primarily with arsenic, with the highest concentrations and the majority of groundwater flow focused along former arroyos. These features represent the greatest contribution of contaminant mass flux toward offsite receptors and are the key to an integrated strategy for remedial design/remedial action. The optimized remedial approach involved a shift from concentration-based compliance to mitigating contaminant flux to protect downgradient receptors. A combination of source control measures and passive groundwater management and treatment approaches was selected to achieve remedial goals and balance the needs of future site development. The remedial approach involves source control, water management, and in situ groundwater treatment, including zero-valent iron (ZVI)-based permeable reactive barriers (PRBs). Site arroyos consist of coarse, highly permeable alluvial deposits, which result in a high groundwater flux system. These conditions required PRB designs with high permeability, sufficient groundwater residence time, and iron content consistent with contaminant loading rates and desired treatment longevity. In the largest arroyo, two ZVI PRBs were constructed in series to passively treat site groundwater and reduce contaminant mass flux. Results indicate that the zero-valent iron barriers have been highly effective for arsenic removal from groundwater, despite treatment challenges driven by groundwater alkalinity and dissolved calcium. The presentation reviews the pre-design testing, key design elements, and field-scale performance of passive groundwater treatment through the reactive barriers. It also provides an overview of the overall remedial construction, including strategies for water management across the site. https://mediacdn.guidebook.com/upload/213718/ZlKj3UQYiVJJeiHQsL4a2B0aGSD3iH1ktQNv.pdf

REMEDIAL ACTION CONSTRUCTION CASE STUDY-EXCAVATION/CONSOLIDATION AND ISS REMEDY, EPA REGION 6, MARION PRESSURE TREATING SUPERFUND SITE, RES CLIN2 CONTRACT TASK ORDER [Cleanup News]

Thu, 7 May 2026 13:56:18 GMT

Watters, C. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 16 slides, 2026

This presentation describes the implementation of remedial action (RA) activities at the Marion Pressure Treating Superfund site. A total of 7,000 CY of DNAPL (creosote) impacted soil was excavated and consolidated in an onsite waste repository. A combined remedial approach was implemented using the in situ soil stabilization (ISS) of ~29,186 CY of DNAPL-impacted soil by large diameter auguring methodology. The construction of a final landfill cap, including final site restoration for permanent erosion control and drainage improvements were also completed as part of the RA. The presentation focuses on the successful mitigation of RA construction challenges and change management approaches, including:

Incomplete site investigation and characterization.

Project delay from additional treatability study testing to evaluate an alternative cement mixture due to difficulties in obtaining Portland Type II cement.

Control of rainwater and excavation flooding.

Understanding and calculating swell quantities and percentages that change depending on soil conditions, which can affect the required footprint or elevations for containment/ landfill areas.

ISS and clay placement work during the wet season created challenges. Import borrow sites may also be impacted by storms.

Locating import materials that meet all the specifications (permeability for clay and plasticity index, organic content, and pH too low for topsoil) in a rural area may be difficult.

https://mediacdn.guidebook.com/upload/213718/pbHtLIF6AeXPWaq5qjkDRBuqTJu1n6XBwGBW.pdf

BUILDING 100 GROUNDWATER BIOREMEDIATION AT THE FORMER DOE PINELLAS PLANT, FLORIDA: REVIEW OF PROGRESS AND OPPORTUNITIES [Cleanup News]

Thu, 7 May 2026 13:55:59 GMT

Looney, B.B., H.H. VerMeulen, and E.D. Fabricatore. SRNL Report SRNL-STI-2025-00262, 58 pp, 2025

Operations at the former Pinellas Plant, particularly in the Building 100 area, resulted in the release of chlorinated organic solvents that contaminated subsurface soil and groundwater. DOE implemented bioremediation as the primary cleanup technology, targeting cVOCs through reductive dechlorination processes that sequentially transform trichloroethylene into daughter products such as dichloroethylene and vinyl chloride. Over more than two decades, monitoring data indicates substantial progress toward remedial goals, with parent cVOC concentrations now reduced to near or below target standards across most of the site. Remaining contamination is largely confined to a localized hot spot beneath Building 100, which continues to act as a source of mass flux sustaining a narrow plume core where daughter product concentrations exceed remedial thresholds. Bioremediation has been supported by multiple deployments using state-of-the-practice and state-of-the-art technology and design strategies, including vertical and horizontal wells for improved access and coverage, and biostimulation and bioaugmentation. To prepare for the next stages of the bioremediation and related decision-making, DOE developed several lines of inquiry, including evaluating whether remediation optimization is needed by assessing the necessity of additional electron donor or bioaugmentation, identifying improved performance metrics, exploring alternative technical and regulatory strategies, and considering future site changes that could impact the cVOC plume and bioremediation progress. The Building 100 area will transition from active bioremediation to an enhanced attenuation (EA) remedy. Recommendations include transition to an optimized EA strategy that relies on natural geochemical zoning without additional biostimulation or bioaugmentation, while incorporating targeted contingencies for hotspot treatment and mid-plume oxygen limitations, strengthening monitoring by aligning with EPA MNA multiple lines of evidence, regularly monitoring the subsurface microbiology in a few locations to provide data on the resilience of the EA bioremediation strategy, document the responsiveness of the microbial community to site conditions, and verify that the enzymes are present to address the specific needs over time. https://www.osti.gov/servlets/purl/3023071

F -- EMERGENCY REMEDIAL RESPONSE SERVICES (ERRS VI) (SOL) [Market/Commercialization]

Thu, 7 May 2026 13:55:44 GMT

U.S. Environmental Protection Agency, Region 1 Contracting Office, Boston, MA
Contract Opportunities on SAM.gov 68HE0125R0004, 2026

This is a total small business set-aside under NAICS code 562910. EPA Region 1 seeks a contractor to support activities associated with emergency response, including sampling, monitoring, site stabilization, containment of spilled materials, waste treatment, restoration, removal actions, transportation, and disposal. Response activities include planning; containment and countermeasures during emergency and removal responses; decontamination and mitigation; treatment, transportation, and disposal operations; restoration; analytical services; demolition; construction and support facilities for removal actions; marine (water) operations; international (transboundary) response; and response times, Level A response capabilities, and integration into the Unified Command (Incident Command System). The contractor shall provide environmental response services for the removal and treatment of oil, petroleum products, hazardous substances, pollutants, and contaminants, as specified in task orders (TOs). The contractor shall also support response actions related to natural and manmade disasters, acts of terrorism, weapons of mass destruction, and chemical, biological, radiological, and nuclear incidents. The award will be an indefinite-delivery/indefinite-quantity contract with fixed rates for labor and equipment and cost-reimbursable elements for other direct costs. Task orders may be issued on a time-and-materials (T&M) or fixed-price basis. The period of performance is from November 30, 2026, through November 29, 2031. Offers are due by 2:00 PM EDT on July 27, 2026. https://sam.gov/workspace/contract/opp/4d9d08a5e4ee473d8b320598529ac6d0/view

F -- F108--32C24126Q0324 BEDFORD RADIATION DECOMMISSIONING (COMBINE) [Market/Commercialization]

Thu, 7 May 2026 13:55:17 GMT

U.S. Department of Veterans Affairs, 241-Network Contract Office 01, Togus, ME
Contract Opportunities on SAM.gov 36C24126Q0324, 2026

This is a service-disabled veteran-owned small business set-aside under NAICS code 562910. The U.S. Department of Veterans Affairs requires a contractor to perform radiological decommissioning of approximately 20 rooms (approximately 6,300 total square feet) in Buildings 17, 18, 70, and 79 at the VA Bedford Healthcare System, Bedford Campus, in Bedford, Massachusetts. Services include review of a historical site assessment and completion of a radiological final status survey in accordance with the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM). The contractor and any subcontractors must be licensed by the Nuclear Regulatory Commission or the Commonwealth of Massachusetts to perform decommissioning work at sites where radioactive materials have been used. The contractor shall comply with interim life safety plans, infection control measures, and egress requirements during construction; coordinate all utility shutdowns with the Contracting Officer's Representative (COR); and comply with all applicable federal, state, and local laws, regulations, standards, and codes. Work shall be coordinated with the COR to minimize impacts on daily operations at the VA Bedford Healthcare System. The award will be made as a firm-fixed-price purchase order. Offers are due by 3:00 PM EDT on May 11, 2026.
https://sam.gov/workspace/contract/opp/2e591e76874d4ec9b40bcffa1e461985/view

F -- EIGHTEEN MILE CREEK SATOC (SOL) [Market/Commercialization]

Thu, 7 May 2026 13:54:45 GMT

U.S. Army Corps of Engineers, Northwestern Engineer Division, Kansas City District, Kansas City, MO
Contract Opportunities on SAM.gov W912DQ26RA031, 2026

This is a total small business set-aside under NAICS code 562910. The U.S. Army Corps of Engineers, Northwestern Engineer Division, requires recurring remedial action efforts at the Eighteen Mile Creek Superfund Site, Operable Unit 1 (OU1), OU2, and OU4, in Niagara County, New York. The overall objective is to perform excavation and transportation, and disposal of lead-contaminated soil that exceeds the Record of Decision (ROD) specified cleanup levels. The award will be a Single Award Task Order Contract (SATOC). The SATOC will provide the Government with a continuity of personnel and institutional knowledge for developing a streamlined response and flexible vehicle for cost-effective soils remediation. It may require, but is not limited to, designs, interim actions, remedial actions, short-term operation and maintenance, laboratory management, reports, and any other actions necessary to implement the soils remedy at the site. Offers are due by 2:00 PM CDT on May 26, 2026.
https://sam.gov/workspace/contract/opp/4eff4fc4f7df4fe6a51bfbfa6e21daed/view

ENHANCING HEAVY METAL REMOVAL USING NOVEL MEDIA SOLUTIONS [General News]

Tue, 28 Apr 2026 14:03:44 GMT

Boussoufa, I. | SMART Remediation, 20 January, Vancouver, Canada, 44 slides, 2026

Advanced treatment methodologies are introduced for the removal of heavy metals, specifically focusing on arsenic, lead, uranium, and mercury. Capabilities of the Cleanit media, a novel iron-based media that efficiently removes lead and arsenic via adsorption and precipitation processes, were presented. The effectiveness of Cleanit-LC in removing toxic heavy metals to meet ultra-low discharge limits was demonstrated, showcasing its potential to significantly reduce environmental impact without altering pH levels, thus promoting cleaner industrial practices at a much lower cost than specialized ion exchange resin. ChemSorb ML, an innovative and versatile amendment for mercury removal, was also covered. ChemSorb ML chemically binds various forms of mercury, including elemental, ionic, and methylmercury, achieving reductions of leachable mercury by >99% and lowering concentrations to parts-per-trillion levels, making it an effective solution for stringent compliance requirements. The presentation concludes with case studies, presentations, and performance data that illustrate the practical applications and benefits of these media in real-world scenarios, underscoring their effectiveness in reducing operational costs and enhancing compliance with environmental regulations. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver_Calgary-2026-%E2%80%93-Imane-Boussoufa.pdf

CURRENT KNOWLEDGE ABOUT PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS) IN THE ATMOSPHERE: FATE, ANALYTICAL METHODS AND RESEARCH PRIORITIES [General News]

Tue, 28 Apr 2026 14:03:25 GMT

Vieira, H.G., M.C. Canela, R.C. Urban, and B.S. Cabrero. | Chemosphere 389:144703(2025)

This comprehensive overview of the current knowledge on PFAS covers: (i) a compilation of information on emission sources, including primary sources (production, manufacturing, use of AFFF, waste handling, marine spraying) and secondary sources (oxidative degradation of neutral PFAS); (ii) proposed classifications of the volatility of these substances based on vapor pressure by EPA; (iii) atmospheric processes that govern gas-particle partitioning, long-range transport, and deposition; (iv) an assessment of current and emerging sampling and analytical techniques, including OTM 45/50 methods; and (v) the identification of priority knowledge gaps. Among the main existing gaps, the validation of improved monitoring strategies and inhalation toxicity studies for neutral precursors could significantly contribute to a robust risk assessment and support regulatory efforts within the evolving global agenda for the phase-out of PFAS.

MANAGEMENT OF CONCRETE AND ASPHALT CONSTRUCTION MATERIALS IMPACTED BY PFAS [General News]

Tue, 28 Apr 2026 14:02:56 GMT

Doudrick, K. and M. Pourghaz. SERDP & ESTCP Webinar Series, March 2026

This webinar highlights research on the management of concrete and asphalt materials impacted by PFAS, including the transport, leaching, and thermal treatment of PFAS and the potential for reusing treated materials. The first presentation discusses recent work focused on the comprehensive management of PFAS-impacted pavements. It features insights from experimental and modeling results of leaching experiments and overall implications for low-temperature thermal treatment of pavement and its reuse following treatment. For thermal treatment, PFAS degradation was investigated across a range of temperatures (400-1000°C) and residence times. Results showed that the natural or added presence of calcium hydroxide enabled >95% PFAS mineralization and >99.99% destruction and removal efficiency (DRE) at 500°C in under 5 minutes. The project also studied the leaching behavior of PFAS from pavements and examined the potential for reusing thermally treated aggregates. Findings support a multifaceted approach to managing PFAS-impacted pavements, balancing effective remediation, environmental protection, and material reuse. The second presentation discusses a project that investigates the mechanisms governing PFAS transport, interaction, and transformation in Portland cement concrete (PCC) and asphalt concrete (AC) to determine whether these materials serve as long-term sources of PFAS release. The research combined lab experiments and field studies to characterize PFAS distribution in impacted materials; quantify sorption, desorption, and transport processes under saturated and unsaturated conditions; and evaluate PFAS release through surface runoff under field-relevant conditions. Experimental results were used to develop practical transport models capable of translating standardized leaching test data into field-scale predictions for intact, damaged, and recycled materials. https://serdp-estcp.mil/resources/details/568b2bbd-73bb-4aec-816e-2158ae15694c/management-of-concrete-and-asphalt-construction-materials-impacted-by-pfas

AIRCRAFT RESCUE AND FIREFIGHTING VEHICLE CLEANING FOR AFFF REMOVAL [General News]

Tue, 28 Apr 2026 14:02:36 GMT

Lang, J. and D. Kay. SERDP & ESTCP Webinar Series, February 2026

This SERDP and ESTCP webinar features innovative approaches and technologies for PFAS removal and/or destruction from fire suppression systems impacted by residual PFAS due to the use of AFFF. The Department of War (DoW) has many fire suppression systems impacted by residual PFAS due to the use of AFFF. At elevated concentrations, PFAS self-assemble and coat surfaces at liquid/solid interfaces, forming waterproof coatings. Recent work demonstrated that water-only rinses may not adequately clean some system components. However, the cost of replacing all existing PFAS-impacted AFFF delivery infrastructure across DoW installations would be expensive and result in equipment downtime. The first presentation showcases insights from disassembling and analyzing PFAS residual content on foam system components from the Oshkosh T-1500 Aircraft Rescue and Firefighting vehicle. Results provide critical information on mission-relevant considerations for fully remediating equipment after baseline treatment, including costs for replacement of the on-board foam system, out-of-service time required for cleaning, and the extent of replacement required to successfully achieve PFAS removal from an on-board foam system. The second presentation features the PFASigator, a treatment unit that provides a practical, effective, and scalable solution for successfully remediating firefighting systems historically exposed to AFFF. Through employing a micelle‑enabled photoactivated reductive defluorination reaction, the solution provides simultaneous PFAS desorption and destruction. The presentation shares results from a field demonstration performed at Tyndall Air Force Base, where PFASigator was connected to a decommissioned firetruck's AFFF tank and associated piping to form a closed recirculation loop. The integrated process of PFAS desorption and destruction removed and mineralized 16.8 grams of PFAS within 48 hours. https://serdp-estcp.mil/events/details/9efc643a-c67f-4035-872a-ae46cb7d0976/aircraft-rescue-and-firefighting-vehicle-cleaning-for-afff-removal

POWDERED ACTIVATED CARBON TREATMENT OF PFAS-CONTAINING WASHWATER FROM AIRCRAFT HANGAR PIPE RINSING [Research]

Tue, 28 Apr 2026 14:02:19 GMT

Hensley, J., J.D. Schober, M. Magnuson, and W.F. Harper.
Remediation 36(2):e70065(2026)

A study investigated the use of powdered activated carbon (PAC) to remove PFAS from washwater used to rinse pipes from aircraft hangar pipe contaminated with AFFF. The untreated washwater contained 249 µg/L of total PFAS. The concentrations were highest for 6:2 FTS (178 µg/L), PFHxA (48 µg/L), PFOA (9.5 µg/L), and PFPeA (6.2 µg/L). PFAS was removed from washwater during 24-h adsorption experiments conducted over a range of adsorbent masses. Temporal increases were observed between the 2- and 4-h total PFAS concentrations during most of the experiments, corresponding to some PFAS species being displaced during complex competitive adsorption mechanisms. After 24 h in the presence of 0.23 g of PAC per liter of solution, removals of 6:2 FTS and PFHxA, two of the short-chain PFAS, were 95% and 86%, respectively. For long-chain PFAS, PFOA, and PFOS were removed to below their quantitation limits in most cases. However, removal of 8:2 FTS was only 52% in the presence of 0.0575 grams of PAC, despite having a relatively high Log K_ow and dipole moment values, also pointing to the complexity of PAC adsorption mechanisms in AFFF contaminated water.

REMOVAL OF PAHS FROM LARGE-SCALE CONTAMINATED SOIL IN A BIOAUGMENTED SLURRY REMEDIATION SYSTEM: OPTIMAL CONDITIONS VERIFICATION, ENVIRONMENTAL PARAMETER MONITORING, AND MICROBIAL COMMUNITY ANALYSIS [Research]

Tue, 28 Apr 2026 14:02:02 GMT

Wang, F., J. Chen, X. Xiao, X. Wang, and S. Chen.
Bioresource Technology 439:133377(2026)

PAH removal was enhanced through a combination of bioaugmentation, condition optimization, and the addition of nitrogen sources and surfactants in a study using a fully functional bioaugmented slurry remediation system to provide a device template for remediation. The study investigated the effects of adding peptone or Tween-80 on PAH removal by agent NS4 in the system. Tween-80 addition under optimal conditions achieved a higher PAH removal efficiency than optimal conditions (with or without peptone addition). System monitoring showed that microbial growth, metabolism, and PAH biodegradation collectively reduced DO and pH while increasing EC. Monitoring these parameters can indirectly reflect microbial activity and PAH removal progress, offering new insights for onsite supervision of PAH remediation. Soil microbial communities differed significantly across environmental conditions. Environmental conditions and remediation time jointly influenced microbial community and functional succession, with environmental conditions exerting a stronger driving force. Network analysis identified 42 microbial operational taxonomic units and 16 PAH-degradation genes as key factors, revealing close interactions between soil microorganisms and PAH-degradation genes.

LABORATORY INVESTIGATION OF INADVERTENTLY GENERATED PCBS RELEASED FROM CONSUMER PRODUCTS INTO LAKE WATER [Research]

Tue, 28 Apr 2026 14:01:45 GMT

Frauenheim, M., X. Liu, K. Woodward, M.R. Mullin, B. Nickel, M. Aguilar, K. Philpott, and
E. Folk. | Journal of Hazardous Materials 503:140974(2026)

A study investigated the occurrence and leaching behavior of inadvertently generated PCBs (iPCBs) in consumer products, including children's toys, craft supplies, paints, soaps, and food packaging. Product selection prioritized items used by children and tribal communities where PCB exposure risks are of heightened concern. Using solvent extraction, sample cleanup processes, and gas chromatography/mass spectrometry analysis, 37-4,268 ng/g of PCB-11 was detected in seven of 114 product types tested and a total of 21 respective color variants. Highest concentrations were found in items containing orange pigments, supporting hypotheses linking PCB-11 to azo pigment synthesis. To assess environmental release potential, batch leaching tests were performed on four representative products across various leach durations (2-28 days) and liquid-to-solid (L/S) ratios (6.7-26.7 mL/g). Results showed that < 10 % of total PCB mass leached into lake water under all conditions, with most remaining sorbed to solids. Foam materials such as glitter foam exhibited notably low leaching across all scenarios, likely due to hydrophobic, porous matrices. Leaching rate and extent were influenced by matrix properties, leach duration, and L/S ratio, with more pronounced release from fiberboard and wax-based matrices. Findings enhance understanding of inadvertent PCB sources in consumer goods and their environmental behavior and underscore the importance of considering product composition in exposure assessments and future risk management decisions.

A PROPOSED EFFECTIVE PRACTICE APPROACH FOR THE CHARACTERIZATION OF DNAPL SOURCE ZONES [Research]

Tue, 28 Apr 2026 14:01:22 GMT

Reynolds, D., K.G. Mumford, S. Bryck, B.H. Kueper, and M. Kavanaugh.
Groundwater Monitoring & Remediation 46(1):49-61(2025)

A study employed the results of a previous virtual site investigation to develop effective practice approaches (methods, strategies, or techniques that have been demonstrated through evidence or experience to yield positive results or outcomes that align with specific, pre-determined goals) for estimating DNAPL footprint and mass, referred to as the Bounding Box and Bulk Retention approaches, respectively. The accuracy and precision of the estimates were assessed using a stochastic approach applied to the virtual sites and evaluated against those by experienced practitioners. The accuracy of the DNAPL footprint and mass estimates did not depend strongly on the borehole density, but the precision of those estimates increased with increasing borehole density. This increase was more pronounced for DNAPL mass than for footprint (i.e., mass estimates were more precise than footprint estimates at the same borehole density), which suggests prioritizing DNAPL source zone delineation during site investigation. When estimates based on grid or random borehole locations were compared to estimates by an expert practitioner, expert judgment was beneficial at low borehole densities but resulted in similar estimates at higher densities, provided that effective practice was used. Estimates based on random borehole locations often outperformed those based on experienced judgment without effective practice, which highlights the importance of data analysis over borehole location for characterizing DNAPL source zones.

ADSORPTION OF ULTRASHORT-, SHORT-, AND LONG-CHAIN PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS): IMPACTS OF ADSORBENT, PFAS TYPE, AND COMPETITIVE IONS [Research]

Tue, 28 Apr 2026 14:01:04 GMT

Smith, S.M., A.X. Wu, T. Smrz, and L. Xiong. Chemosphere 395:144836(2026)

This study assessed the adsorption efficacy of commercially available anion exchange resin (AEXR) and granular activated carbon (GAC) adsorbents across a series of ultrashort-chain (USC), short-chain (SC), and long-chain (LC) PFAS, with an emphasis on the USC class. Results uncover the relative adsorption selectivity for AEXR vs GAC, the importance of the AEXR functional group, and the impact of competitive inorganic anions across different PFAS and adsorbents. A dynamic column test validated the capacity trends from batch adsorption testing in relation to bed volumes until breakthrough. The structure-property relationships identified expand on the fundamental understanding of adsorbent technology for PFAS remediation applications and highlight the challenges in expanding the application use case, particularly for USC PFAS remediation from water.

PFAS STABILIZATION: COMPREHENSIVE BENCH SCALE EVALUATION OF AMENDMENTS, DOSAGE, AND BINDERS [Research]

Tue, 28 Apr 2026 14:00:50 GMT

Torney, K. | SMART Remediation, 20 January, Vancouver, Canada, 22 slides, 2026

A bench scale study evaluated a combination of stabilizers and binders to provide a more comprehensive, comparative review of amendment and help inform remediation planning at a site with AFFF-impacted soil. Bench scale testing was conducted on soil collected from the site. The study included three stabilizers (proprietary and generic) at four dose percentages (0.2%, 0.5%, 1%, and 2.0% dry weight) with or without binder for a total of 26 mixes, including control samples. The study was designed to report a four-point (plus unamended reference) dose response relationship for each mix and be consistent with the minimum testing regime for similar peer-reviewed published studies. The testing regime included compaction, hydraulic conductivity testing, geotechnical analyses, EPA LEAF 1314 and 1315, low-level liquid chromatography mass spectrometry, total oxidizable precursor assay (TOPA), and Synthetic Precipitation Leaching Procedure for comparison to LEAF methods. Results informed the following testing objectives: 1) relative performance of proprietary and non-proprietary amendments at varying dosages; 2) dosage/quantity of amendment required to meet site-specific remediation targets; 3) effectiveness of binders to enhance stabilization performance; and 4) comparison of leaching methods. Additionally, geotechnical and hydraulic conductivity data were used to interpret leaching results and were also assessed for potential field-scale quality control, and TOPA data were assessed to determine amendment activity with respect to precursors. Study results contribute to the PFAS soil amendment efficacy literature and can assist in decision-making with respect to amendments, leaching/analytical approaches, implications, and field implementation. Use of amendments to mitigate PFAS contamination represents a sustainable option that reduces soil landfilling and minimizes transportation-related emissions. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver-2026-%E2%80%93-Korene-Torney.pdf

FACILITATED TRANSPORT OF ORGANIC CONTAMINANTS IN A HIGH CONCENTRATION, MULTICOMPONENT PLUME [Demonstrations]

Tue, 28 Apr 2026 14:00:29 GMT

Mackay, D.M., B. Myller, G.C. Bianchi-Mosquera, B.D. Honeyman, M. Schirmer, R.M. Allen-King, W.P. Ball, and R.L. Stollar. Groundwater Monitoring & Remediation 46(1):62-83(2026)

A field experiment evaluated the transport of organic contaminants in a plume from hazardous waste disposal areas at the Rocky Mountain Arsenal. The plume contained many xenobiotic contaminants with widely varying expected mobilities. In lab tests, aquifer sediments showed significant capacity for sorption of organic contaminants from synthetic groundwater, suggesting contaminants' mobilities in situ could have been retarded. Sediment cores showed sorbed concentrations of contaminants at or below detection levels, suggesting sorption in situ was minimal. The field experiment made direct observations of organic contaminant transport under plume conditions by flushing tracer-amended organic-free water through the plume. No contaminants were retarded in their migration compared to the tracer, suggesting negligible sorption of the contaminants in situ. The concentration of colloids, cosolvents, and anionic surfactants in the plume was too low to have had a significant effect on contaminant migration. Though not monitored, non-ionic surfactants could have reduced sorption somewhat if they had constituted a significant fraction of the uncharacterized dissolved organic carbon. Though monitored only indirectly, micro- or nano-plastic particles were deemed unlikely to have significantly affected organic solute transport. Microemulsions may have been present and facilitated the transport of contaminants, but only indirect evidence was obtained. Although the specific reasons for the enhanced mobility of organic contaminants could not be confirmed, the study showed that unknown plume components can be responsible for the suppression of sorption, suggesting new lab research is needed to expand understanding of factors affecting sorption. https://ngwa.onlinelibrary.wiley.com/doi/epdf/10.1111/gwmr.70028

COLLOIDAL ACTIVATED CARBON PERMEABLE REACTIVE BARRER TO REDUCE PFAS MIGRATION FROM IMPACTED GROUNDWATER INTO OAKLAND BAY [Demonstrations]

Tue, 28 Apr 2026 13:59:13 GMT

Nunez, D. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 21 slides, 2026

PFAS concentrations, ranging from 7.6 to >300,000 ng/L, were detected in groundwater at Alameda Point (Former Naval Air Station Alameda) from past use of AFFF at Site 14. A large-scale pilot test is underway to test the effectiveness of an in situ colloidal activated carbon (CAC) barrier at reducing the mass flux of PFAS migration into Oakland Harbor. The 720-foot PRB was designed using results from a pre-field mobilization lab test using flow-through column tests and contaminant mass flux studies, with 2%, 5%, and 7% CAC dosages. Post-application monitoring over three consecutive quarters shows significant PFAS reduction across three transects along the PRB:

Transect 1: Upgradient well (10 ft.) reductions ranged from -10% to 53%, downgradient PRB edge well reductions ranged from 97% to 99%, and downgradient well (17 ft.) reductions ranged from 88% to 99%.

Transect 2: Upgradient well (18 ft.) reductions ranged from -9.2% to 90%, downgradient PRB edge well reductions ranged from 98% - 99%, and downgradient well (18 ft.) reduction ranged from 46% - 79%.

Transect 3: Upgradient well (14 ft.) reductions ranged from 20%-52%, downgradient PRB edge well reductions ranged between 62% - 99%, and downgradient well (18 ft.) reductions ranged between 68% - 89%.

https://mediacdn.guidebook.com/upload/213718/FuIbQVugUYxtCATmDmxNTZvZi2ORX63cxriX.pdf

PILOT SCALE TREATMENT OF PFAS-CONTAMINATED GROUNDWATER IN A SUBSURFACE FLOW CONSTRUCTED WETLAND-EVALUATING MULTIPLE PLANT SPECIES [Demonstrations]

Tue, 28 Apr 2026 13:58:52 GMT

Liljestrom, O., D. Rosenquist, D.B. Kleja, A. Enell, and L. Ahrens.
Environmental Pollution 386:127199(2025)

Subsurface flow constructed wetlands were investigated for treating PFAS-contaminated groundwater. The wetlands used a peat, biochar, and lightweight expanded clay aggregate filter substrate, planted with either tufted sedge (Carex elata), fiber hemp (Cannabis sativa Futura 75), or an intercropping of the two Salix clones S. Wilhelm and S. Loden. The experiment was conducted under field conditions in Sweden during one growing season using PFAS-contaminated groundwater impacted by landfill leachate. PFAS accumulated in all plant species and the peat and biochar part of the filter substrate, with short-chain PFAS and PFCAs dominating when considering the whole plants (57% and 77% of ∑PFAS, respectively) and long-chain PFAS and PFSAs dominating in the peat and biochar filter substrate (77% and 54% of ∑PFAS, respectively). Sorption to the filter substrate was the primary mechanism for PFAS removal. The highest plant PFAS concentrations were found in leaves, followed by roots, for all species. A difference in the PFAS composition profile was found when comparing different plant tissues, with PFCAs dominating in leaves (84% of ∑PFAS) and PFSAs dominating in roots (66% of ∑PFAS). All plant species had an above-ground tissue/water phase concentrations >10/1 for C3-PFCA (PFBA). This was also observed for C. sativa with C4- and C7-PFCAs (PFPeA, PFOA), and C4- and C5-PFSAs (PFBS, PFPeS), for C. elata with C8-PFSA (L-PFOS), and for S. Loden with PFPeA. ∑PFAS phytoextraction potential from landfill leachate-impacted groundwater (mg/ha yr) was estimated to be 940 ± 670 for C. sativa, 390 ± 310 for S. Loden, 330 ± 160 for S. Wilhelm, and 160 ± 56 for C. elata. https://www.sciencedirect.com/science/article/pii/S0269749125015738/pdfft?md5=abeaf3db92a84b10bdc3258c4a524c64&pid=1-s2.0-S0269749125015738-mainext.pdf

RA CASE STUDY EPA REGION 5, VELSICOL CHEMICAL CORPORATION SUPERFUND SITE RES CLIN 2 – OU1 DOWNGRADIENT VERTICAL BARRIER WALL (DGVBW) CONSTRUCTION, ST. LOUIS, MICHIGAN [Cleanup News]

Tue, 28 Apr 2026 13:57:40 GMT

Srirangam, R. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 20 slides, 2026

The Downgradient Vertical Barrier Wall (DGVBW) Construction Project at the Velsicol Chemical Corporation Superfund Site provides a compelling case study in highlighting significant construction challenges that are overcome with structured adaptive management strategies. The presentation explores topics implemented to overcome remedial action challenges while constructing the DGVBW, a 4,300-ft-long sealed steel combination sheet-pile and cylindrical king-pile containment wall installed ~30-ft deep into the subsurface of the Pine River. The DGVBW was designed as a source control remedy to intercept potential subsurface migration of DNAPL and dissolved-phase contaminants into Pine River. Key to the project's success was implementing adaptive management strategies to address design requirements and associated changes and incorporate stakeholder feedback promptly to stay on schedule. The framework enabled rapid decision-making and alignment among regulators, while maintaining compliance with all project requirements. The adaptive management process included field verification of existing site conditions, constructability reviews enabling design modifications, and planning activities to resolve technical uncertainties. A multi-tiered communication strategy included weekly construction, agency, and interagency coordination meetings, onsite briefings, drone aerial imagery to review existing and changing site conditions, reviewing real-time digital monitoring of dust, noise, turbidity, water level changes, and seismic data during construction, and public engagement sessions that helped maintain transparency. The presentation highlights construction challenges that were overcome while working near a sensitive residential setting. This case study provides insights into lessons learned for managing large-scale remedial action with high community visibility. It also underscores the importance of strategic communication, adaptive management, and cross-agency collaboration in delivering technically sound and publicly supported outcomes. https://mediacdn.guidebook.com/upload/213718/KvcWyQ92097h13KSPqigw6PDVJCUDxyQWjEx.pdf

A HOLISTIC APPROACH TO SITE REMEDIATION: A DECADE OF INTEGRATED IN SITU REMEDIES FOR MULTIPLE AOCS IN A COMMERCIAL SETTING [Cleanup News]

Tue, 28 Apr 2026 13:57:14 GMT

Srirangam, R. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 16 slides, 2026

Over the past decade, a holistic site remediation strategy was implemented to manage 54 areas of concern (AOCs) at a commercial site in the Northeastern U.S. impacted by contaminants ranging from VOCs and PAHs to PCBs and heavy metals. Remedial activities completed included the excavation of PCBs, SVOCs, and radiologically impacted soil to address 18 of the AOCs, in situ thermal remediation of a 3.1-acre area, removing 34,000 lbs of VOCs, ISCO of VOC-impacted soil and groundwater in a secondary 1.2-acre area, and the dredging of sediments within a downgradient drainage ditch. Engineering controls, including environmental capping and institutional controls, were established across the site with site redevelopment to limit human exposure, ensuring long-term efficacy and regulatory compliance. Following aggressive technologies like in situ thermal and chemical oxidation, the shift towards enhanced in situ bioremediation (EISB) and in situ biogeochemical transformation (ISBGT) was initiated based on long-term groundwater monitoring data demonstrating a shift toward naturally reducing conditions. A biobarrier was installed to prevent plume migration beyond the immediate source areas. EISB's application of organic substrates catalyzed microbiologically driven processes to further degrade residual contaminants. The barrier was optimized using ISBGT, which facilitated the transformation of existing geochemical conditions to create reactive minerals for accelerated monitored natural attenuation. The presentation demonstrates the significance of a holistic approach in managing complex contaminant profiles and the pivotal role of a comprehensive post-monitoring strategy in guiding and fine-tuning remedial transitions, leading to successful multi-faceted site restoration. https://mediacdn.guidebook.com/upload/213718/wOw0xhkbzPs8Z2LRLydn0hkBz4CM2Z4ErKsf.pdf

BUGS TO THE RESCUE: BUILDING A BIOBARRIER FOR MANAGING CVOC-IMPACTED GROUNDWATER [Cleanup News]

Tue, 28 Apr 2026 13:56:49 GMT

Patel, P. | SMART Remediation, 20 January, Vancouver, Canada, 20 slides, 2026

A study investigated the feasibility of a biobarrier system leveraging bacterial communities and solid organic carbon substrates. The approach aimed to provide a sustainable, cost-effective alternative to overcome the high upfront and replacement costs associated with zero-valent iron (ZVI) permeable reactive barriers (PRBs), while effectively managing highly impacted groundwater. The bench-scale study used readily available and cost-effective solid carbon substrates such as sawdust and peat. Batch microcosm, flow-through column studies, and column experiments demonstrated that peat supported complete reductive dechlorination of TCE to ethene, while sawdust stalled at cDCE and produced excessive methane. Gene analysis indicated that peat microcosms fostered higher populations of Dehalococcoides and functional vcrA genes, correlating with superior TCE degradation performance. Findings identified peat as the preferred substrate for biobarrier implementation and a full-scale biobarrier was constructed, spanning 125 m (410 ft) in length and 5.5 m (18 ft) in depth. The biobarrier achieved substantial CVOC reductions, including average reductions of 70% and localized reductions of up to 90% within two years of operation. Provisions were made for future injections of liquid-based carbon substrates to boost performance or replenish the solid substrates if needed. Over a five-year monitoring period, the biobarrier achieved a 97% reduction in contaminants without requiring maintenance or additional substrate injections. Findings provide valuable insights into substrate selection and system optimization, enabling effective and sustainable long-term groundwater remediation in challenging conditions. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Toronto-2026-%E2%80%93-Paresh-Patel.pdf

CERCLA REMOVAL ACTION AT MOJAVE NP, CA (SOL) [Market/Commercialization]

Tue, 28 Apr 2026 13:56:17 GMT

U.S. Department of the Interior, National Park Service, Washington Contracting Office
Contract Opportunities on SAM.gov 140P2126Q0049, 2026

This is an Indian Small Business Economic Enterprise (ISBEE) set-aside under NAICS code 562910. The U.S. Department of the Interior, National Park Service seeks a contractor to perform a Non-Time Critical Removal Action under CERCLA at the Hidden Hill Mine site within Mojave National Preserve, CA. The site is a small, remote abandoned mine covering 5 acres at an elevation of ~3,400 feet. Work includes removing approximately 69 cubic yards (CY) of commingled tailings and potentially affected underlying soil (assumed 1-foot depth) over approximately 1,850 square feet, including ancillary soils that may become commingled during excavation. The total estimated removal is 100 CY (150 tons using 1.5 tons/CY). The scope also includes preparing post-award plans, characterizing material, transporting it to approved disposal, collecting/analyzing confirmation samples, and preparing a Response Action Completion Report (RACR). Estimates are based on prior site investigations. The firm-fixed-price contract combines lump-sum and unit-priced items, subject to the variation in quantity clause, with an established ceiling and notification requirements. A 100% payment bond, 100% performance bond, and liability insurance are required before performance. A group site visit is scheduled at 10:00 AM on April 9, 2026. Attendance is strongly encouraged but not mandatory; individual site visits will not be accommodated. Offers are due by 3:00 PM PDT on May 5, 2026. https://sam.gov/workspace/contract/opp/25038d92ad9245159df111010adc4191/view

COMPREHENSIVE UTILIZATION OF IRON ORE TAILINGS: A REVIEW OF SUSTAINABLE PRACTICES AND TECHNOLOGIES [General News]

Thu, 9 Apr 2026 16:36:49 GMT

Wu, W., K. Kang, Q. Ye, A. Luo, J. Zhang, J. Wang, and S. Shi.
Mining, Metallurgy & Exploration 43:413-430(2026)

This paper reviews the physicochemical properties of iron ore tailings (IOT), analyzes the environmental hazards associated with their accumulation, and summarizes recent advancements in their comprehensive utilization, including recovering valuable elements, preparing backfill materials, developing construction materials, synthesizing soil conditioners, and producing chemical materials such as adsorbents and catalysts. Despite the promising pathways, the transition from lab research to industrial application faces challenges related to economic viability, process standardization, and long-term environmental safety. Future research should focus on developing low-cost activation technologies, enhancing the long-term durability and eco-efficiency of IOT-derived products, and integrating policy-driven incentives to promote market adoption. The review aims to provide a scientific basis and strategic reference for the high-value, sustainable utilization of IOT in the context of a circular economy.

DISPERSED ALKALINE SUBSTRATE PASSIVE TREATMENT TECHNOLOGY FOR HIGHLY CONTAMINATED ACID MINE DRAINAGE: 20 YEARS OF SUCCESSFUL APPLICATION [General News]

Thu, 9 Apr 2026 16:36:34 GMT

Leon, R., R. Millan-Becerro, F. Macias, C.R. Canovas, C.M. Neculita, C. Ayora and J.M. Nieto. Water Research 288(Part B):124683(2026)

Over the past two decades, Dispersed Alkaline Substrate technology (DAS) has emerged as a highly effective passive approach to treating acid mine drainage with extreme acidity and metal loading. DAS systems maintain high porosity and neutralization capacity without rapidly clogging by mixing alkaline materials (limestone, magnesia, barium carbonate, or industrial by-products) into an inert wood-chip matrix. The technology evolved from lab trials to pilot and full-scale field testing, using multi-step systems integrated with Natural Fe-Oxidizing Lagoons (NFOL) for pre-oxidation, which have demonstrated their long-term effectiveness for acidity and metal removal. The sustainability and applicability of the process have been improved by the search for new reagents (e.g., MgO for divalent metals removal, BaCO₃ for sulfate removal, wood ash or calcite-rich waste for cost reduction). Field trials in diverse regions, from the Iberian pyrite belt to South Africa, Canada, South America, Asia, Europe, and Oceania, report net acid removal often exceeding 95% and near complete retention of metal(loid)s such as Al, Cu, Zn, Pb, and As. Mineralogical analyses indicate that contaminants precipitate primarily as hydroxides, oxyhydroxides, and sulfates (e.g., schwertmannite, basaluminite, barite), allowing targeted valorization of metal-rich sludges. Remaining challenges include assessing long-term reagent life under variable hydrological conditions, extending full-scale use to phosphogypsum and other industrial leachates, and developing strategies for residue stabilization and resource recovery. This review aims to synthesize these developments, assess current performance, and identify future research needs for the advancement of passive DAS treatment technology.

WASTE GAS CAPTURE FROM ABANDONED MINES [General News]

Thu, 9 Apr 2026 16:36:13 GMT

Bobsein, B. 27th Annual PA AMR Conference, 14-16 October, State College, PA, 47 minutes, 2025

Mines vent methane out of the workings for safety purposes, but little is being done to capture this resource and utilize it. Today, waste methane from mines is predominantly being vented as a potent greenhouse gas, continuing for decades after a mine has been inactivated or abandoned. This energy source can be harnessed while furthering economic development in Pennsylvania, and in other industrial communities across the U.S. A project was pioneered to capture waste methane from abandoned mines and bring it to market as Remediated Mine Gas (RMG), one of just three such RMG operations in the U.S. EPA identified over 60 RMG project opportunities from abandoned mines, which could lead to thousands of jobs and billions of dollars in economic output. If leveraged correctly, RMG projects can lead to additional energy infrastructure being built out, getting reliably dispatchable fuel to market, improving grid resilience, lowering greenhouse gas emissions, and driving manufacturing and AI investment to these underserved areas. https://www.youtube.com/watch?v=nLZW9XXA2QM

PROACTIVE MINE POOL MANAGEMENT: IMPLEMENTING A REMOTE TELEMETRY MONITORING NETWORK IN PENNSYLVANIA'S BITUMINOUS DISTRICT [General News]

Thu, 9 Apr 2026 16:35:54 GMT

May, S. 27th Annual PA AMR Conference, 14-16 October, State College, PA, 43 minutes, 2025

Pennsylvania's Department of Environmental Protection's Bureau of Abandoned Mine Reclamation is initiating a long-term monitoring program to address the challenges posed by deep mine pools in the bituminous district. The mine pools, remnants of extensive historical coal mining, present significant risks of blowouts, subsidence, and other adverse environmental impacts if left unmanaged. An innovative network of monitoring wells equipped with remote telemetry systems is being established to enhance proactive readiness and improve mitigation strategies. The technology will provide real-time data on water levels, pressure changes, and other critical parameters, enabling immediate response to fluctuations indicative of potential hazards. The program aims to develop a robust dataset to predict trends and model behaviors within the interconnected mine pool systems. By integrating these monitoring efforts with geospatial analysis and predictive modeling, the initiative seeks to bolster the state's ability to anticipate and prevent catastrophic events. The presentation outlines the program's design, early implementation steps, and the broader implications for mine pool management. Attendees gained insights into leveraging advanced telemetry for sustainable reclamation practices and enhancing community and environmental resilience in areas impacted by legacy mining activities. https://www.youtube.com/watch?v=xjje3m0Shb8

DEPTH-DEPENDENT HETEROGENEITY IN TOPSOIL STOCKPILES INFLUENCES PLANT-MICROBE INTERACTIONS AND REVEGETATION SUCCESS IN ARID MINE RECLAMATION [Research]

Thu, 9 Apr 2026 16:35:24 GMT

Murawska-Wlodarczyk, K., P. Kushwaha, O. Stokes, C. Rasmussen, J.W. Neilson, R.M. Maier and A. Babst-Kostecka. Science of The Total Environment 1003:180673(2025)

A study evaluated soil health parameters within the 28-meter depth profile of a 14-year-old copper mine topsoil stockpile to identify key indicators of revegetation success in a semi-arid ecosystem. Plant growth was monitored using non-invasive root phenotyping in rhizoboxes filled with soils collected from different depth layers, allowing assessment of how biochemical variability in stockpiled materials influences germination and early establishment. Machine learning models integrating soil properties, plant responses, and sequenced soil bacterial/archaeal and fungal DNA identified key indicators influencing plant performance. Results revealed significant heterogeneity in soil quality across depths, with distinct biochemical and microbial profiles shaping vegetation establishment. The upper 10 m exhibited greater potential for supporting growth, with seedling survival reaching 95%, whereas deeper layers showed drastically reduced survival, sometimes as low as 0%, due to microbial shifts to anoxic conditions and elevated Fe and Mn toxicity. Fungal communities played a dominant role in germination, while archaea were more influential during later plant establishment. Soil parameter comparisons before and after the experiment indicated recovery processes initiated by plant-soil feedback, including fungal community renewal. Findings highlight the role of stockpile formation in preserving soil health attributes critical for ecological recovery and provide practical insights for optimizing land reclamation in semi-arid ecosystems. https://www.sciencedirect.com/science/article/pii/S0048969725023137/pdfft?md5=bb42e8e16ab1043283ec6bc06042c0d5&pid=1-s2.0-S0048969725023137-main.pdf

EVALUATION OF BOREAL PLANT AND MICROBE COMMUNITIES ON TAILINGS SOLVENT RECOVERY UNIT (TSRU) TAILINGS: A MESO-SCALE GREENHOUSE STUDY [Research]

Thu, 9 Apr 2026 16:35:07 GMT

Degenhardt, D., A. Van Dongen, A.-l. Balaberda, D.A. Escolastico-Ortiz, and C. Martineau.
Chemosphere 387:144662(2025)

A study evaluated the ability of Tailings Solvent Recovery Unit (TSRU) tailings to support upland and wetland vegetation under various thin capping designs using peat mineral soil mix (PMM) and coarse sand tailings (CST). A 30 cm PMM cover cap successfully supported upland and wetland vegetation for three years, while a thicker, multi-layer cap of 30 cm PMM above 20 cm of CST further improved plant survival and growth. The cap was found to effectively act as a barrier, protecting vegetation from the adverse effects of pyrite oxidation in the TSRU tailings. While the TSRU tailings acidified (pH ≤ 2) under all capping treatments, the thickest cap (30 cm PMM/20 cm CST) delayed acidification by one year. TSRU and CST had low microbial biomass and diversity, with bacterial communities mostly composed of sulfur oxidizers and acidophilic taxa. In contrast, the PMM layer maintained a higher microbial biomass, diversity, and stability across all treatments, highlighting its potential to enhance plant-microbe interactions and improve the reclamation success of TSRU tailings. https://www.sciencedirect.com/science/article/pii/S0045653525006101/pdfft?md5=e1a1ae4715a1549a7f84720ff3f5669c&pid=1-s2.0-S0045653525006101-main.pdf

ASSESSMENT OF BIOCHAR, COMPOST, AND IRON AMENDMENTS TO ENHANCE THE PHYTOSTABILISATION OF ARSENIC IN GOLD MINE WASTE BY THE AUSTRALIAN NATIVE PLANT SPECIES POA LABILLARDIERI (STEUD.) [Research]

Thu, 9 Apr 2026 16:34:49 GMT

Besedin, J.A., L.S. Khudur, D.A. Besedin, P. Netherway, A.L. Juhasz, A. Batra, F. Huslina, S.K. Biek, G. Aguilar, and A.S. Ball. Chemosphere 391:144728(2025)

A greenhouse mesocosm experiment was conducted for 100 days to optimize phytostabilization using P. labillardieri with soil amendments, 5% biochar, 5% compost, and 1% ferric oxide (Fe₂O₃), applied individually or in combination. The combined treatment of 5% biochar and 5% compost (BC) significantly (p ≤ 0.01) increased root As concentrations (657 ± 135 mg/kg) compared to the unamended control (317 ± 12 mg/kg). Shoot As concentrations ranged between 30 and 44 mg/kg for all treatments. The BC treatment increased soil-to-root bioaccumulation to 0.97, 1 being optimal for phytostabilisation. Soil As concentrations significantly decreased (677 ± 21.5 mg/kg) compared to the unamended control (781 ± 6.32 mg/kg). In addition, As removal from soil improved from 6.83 ± 5.93 to 50 ± 24 mg/m³, and in vitro bioaccessibility decreased from 47.0 ± 6.92 to 35.8 ± 0.72%. The BC treatment had greater root (0.01 ± 0.01 g), shoot (0.05 ± 0.02 g), and total biomass (0.06 ± 0.03 g), compared to the control (0.004 ± 0.002 g root biomass; 0.01 ± 0.01 g shoot biomass; 0.014 ± 0.012 g total biomass). The BC treatment shows potential to assist phytostabilisation using P. labillardieri. A field trial is recommended using the newly developed phytostabilization technique to validate the results under natural climatic conditions.

PHYTOREMEDIATION STRATEGIES FOR THE RECLAMATION OF TAILINGS AND MINING SOILS IN AN ACTIVE OPEN-PIT SITE [Research]

Thu, 9 Apr 2026 16:34:16 GMT

Diaz, A.M., R. Forjan, J.L.R. Gallego, L. Benavente-Hidalgo, A. Sanchez-Poyal, P. Diaz-Garcia, J.M. Menendez-Aguado and D. Baragano.
Environmental Research 275:121464(2025)

Two phytoremediation strategies were evaluated at an active open-pit mining site within a dunite deposit, an ultramafic igneous rock rich in nickel. Strategies included phytostabilization for tailings and phytoextraction for mining soil, composed of natural soil aggregates mixed with fine dunite fragments. Tailings had an alkaline pH (8.8), low organic matter content (9.4 g/kg), and high available Ni concentrations, requiring immobilization using compost, vermicompost, biochar, and vermichar. Amendments were tested in 1-kg pots over 180 days, assessing soil properties, plant growth, and Ni accumulation in Lolium perenne L. Mining soil showing a more neutral pH (7.6), higher organic matter (106 g/kg), and high available Ni contents underwent phytoextraction supported by EDTA and citric acid in a parallel experiment. Phytostabilization with compost, vermicompost, and vermichar significantly reduced available Ni (<5 mg/kg), improved plant growth, and increased labile carbon, while biochar was less effective. Vermicompost proved particularly beneficial, enhancing nutrient and carbon availability, minimizing Ni leaching, and preventing excessive accumulation in plant aerial parts. Phytoextraction was successfully implemented without altering soil properties, with EDTA boosting Ni accumulation in aerial biomass up to 400 mg/kg, outperforming citric acid. Findings highlight the adaptability of phytoremediation, demonstrating the successful application of both strategies in the same environment, with Lolium perenne L. functioning either as a metal accumulator or a phytostabilizing plant depending on the amendments used. https://www.sciencedirect.com/science/article/pii/S0013935125007157/pdfft?md5=0d1c4144fcf31a18f4d03b4a7e8b125f&pid=1-s2.0-S0013935125007157-main.pdf

FACTORS INFLUENCING WATER QUALITY IN SURFACE WATER AND ALLUVIAL GROUNDWATERS DOWNGRADIENT OF A RECLAIMED SURFACE COAL MINE IN THE POWDER RIVER BASIN OF SOUTHEASTERN MONTANA, USA [Research]

Thu, 9 Apr 2026 16:33:55 GMT

Keeshin, S.I., S.A. Ewing, E.B. Meredith, R.A. Payn, and A. Hunt.
Hydrogeology Journal 33:715-737(2025)

Geochemical trends in water quality were evaluated downgradient of a fully reclaimed landscape at the former Big Sky Mine in the Rosebud Creek watershed over 3 years, including bond release in 2022. Within 6 km downgradient from the reclaimed area, sulfate concentrations decreased from ~3,500 to 1,800 mg/L within the Miller Coulee alluvial aquifer. Major ions, δ34SSO4 values, and residence time tracers suggest that the observed decreases in sulfate concentration result from a combination of dilution by mixed-age inflows and incomplete transit of the high salinity plume from the mine boundary. Bedrock and alluvial aquifers of the Rosebud Creek corridor contained contributions of millennia-old regional groundwater, which may serve to mitigate mine-derived high-salinity waters. Rosebud Creek, which traverses the outflow zone of Miller Coulee in the study area, exhibited high sulfate concentrations during low flows and consistent downgradient increases in sulfate concentration. The possibility of plume dynamics in Miller Coulee suggests that the greatest water quality impacts may not yet have reached Rosebud Creek. This article is Open Access at https://link.springer.com/article/10.1007/s10040-025-02898-z

SOURCE APPORTIONMENT OF LEAD IN THE SAN JUAN WATERSHED (USA): INFLUENCES FROM WEATHERING OF MINERALIZED AND SEDIMENTARY DEPOSITS [Research]

Thu, 9 Apr 2026 16:33:39 GMT

Wilkin, R.T., M.R. Noerpel, M. Rovero, L. Costantino, I. Bowen, and C. Larrick.
ACS Environmental Au 5:583-593(2025)

A study examined the sources and distribution of Pb within the San Juan watershed in southwestern Colorado and the Four Corners region (Colorado, New Mexico, Arizona, and Utah). Samples collected from 2018 to 2021 included seeps and springs located within the mineralized headwaters region, surface water, and sediments along an ~570 km stretch of riverbed. Concentrations and isotopic compositions of Pb showed that source attribution using stable Pb isotope ratios (²⁰⁶Pb/²⁰⁴Pb, ²⁰⁷Pb/²⁰⁴Pb, and ²⁰⁸Pb/²⁰⁴Pb) facilitated analysis of metal dilution and changing Pb sources. In upstream reaches, Pb from landscape disturbance related to mining operations and weathering of mineralized geologic units represented the most significant Pb source, accounting for as much as 90% of the Pb within upper Animas River sediments. Pb attributed to the mining-impacted headwaters decreased downstream through the Animas River and San Juan River and represented up to about 50% of the Pb in downstream sediments. The proportion and mass of Pb derived from the mining district were reduced in downstream areas due to increased sediment delivery to the central river channels from tributaries and weathering of Paleozoic- to Tertiary-aged sedimentary deposits. Analysis demonstrates that Pb isotope ratios can be used to effectively trace Pb transport through watershed systems where multiple Pb sources exist and where Pb concentrations may be similar to geogenic values. Results indicate that the spatial and temporal variation of Pb isotopic signatures is associated with multiple contributions from natural sources, which are influenced by seasonality and hydrological factors. https://pubs.acs.org/doi/pdf/10.1021/acsenvironau.5c00070?ref=article_openPDF

PERFORMANCE OF PILOT-SCALE PASSIVE TREATMENT TESTS OF A CONTACT OXIDATION MANGANESE-OXIDIZING BACTERIA FOR MANGANESE-CONTAINING MINE WATER [Demonstrations]

Thu, 9 Apr 2026 16:33:24 GMT

Semoto, Y., T. Hamai, Y. Masaki, M. Ikeda, M. Okumura, N. Miyata, T. Yasutaka, and T. Katayama. Proceedings from the International Mine Water Association Conference, 7-11 July, Braga, Portugal, and Oviedo, Spain, 7-11 July, 2025

A pilot study evaluated the performance of a pilot-scale passive treatment system consisting of a limestone bioreactor and a fiber filter material bioreactor in series and employing a contact oxidation method utilizing Mn-oxidation bacteria for neutral mine water containing Mn and Zn over approximately one year of operation. In the limestone bioreactor, the maximum Mn removal rate reached 49.7 g/m³/day under aeration at water temperatures of ~20°C. Even under low water temperatures of around 5°C, the average Mn removal rate of the system reached 5.65 g/m³//day at a hydraulic retention time of 3 days in a limestone bioreactor. https://www.imwa.info/docs/imwa_2025/IMWA2025_Semoto_874.pdf

THE EVALUATION OF A PILOT PERVIOUS CONCRETE TREATMENT SYSTEM FOR ACID MINE DRAINAGE TREATMENT [Demonstrations]

Thu, 9 Apr 2026 16:33:06 GMT

Shabalala, A., M. Ngomane, and N. Khanyile.
Proceedings from the International Mine Water Association Conference, 7-11 July, Braga, Portugal, and Oviedo, Spain, 7-11 July, 2025

A pervious concrete (PERVC) reactive barrier system was designed and evaluated to remediate AMD at an abandoned coal mine site. Following treatment with PERVC, the pH increased from 2.6 to 12. Al, Fe, Zn, Ni, Co, Cu, and Mn were effectively removed from the mine water with efficiency levels of 97% to 100%. PERVC offers alternative technology for contaminated mine waters that can be used for full-scale implementation. https://www.imwa.info/docs/imwa_2025/IMWA2025_Shabalala_880.pdf

EVAPOTRANSPIRATION COVER DESIGN OPTIMIZATION – A CASE STUDY [Demonstrations]

Thu, 9 Apr 2026 16:32:50 GMT

Subotskaya, Y. and L. Breckenridge.
Proceedings from the International Mine Water Association Conference, 7-11 July, Braga, Portugal, and Oviedo, Spain, 7-11 July, 2025

A new evapotranspiration (ET) cover was designed, field-tested, and optimized with computer modeling for the tailings storage facility at the Zangazeur Copper-Molybdenum Complex in Kapan, Armenia. Field data collected from ET cover test cells, soil characteristics, and climate data were combined to create a variably saturated groundwater flow model, which simulated the effectiveness of the cover for more than 10 years. The model was validated against the field-observed measurements of moisture. A minimum cover thickness is recommended to prevent breakthrough. https://www.imwa.info/docs/imwa_2025/IMWA2025_Subotskaya_897.pdf

BIOACCUMULATION OF ARSENIC IN MINE WASTE CONTAMINATED SOIL USING POA LABILLARDIERI++998 (STEUD.) AND SOIL AMENDMENTS: A SHORT-TERM PILOT TRIAL [Demonstrations]

Thu, 9 Apr 2026 16:01:50 GMT

Besedin, J.A., D.A. Besedin, L.S. Khudur, S.K. Biek, G. Aguilar Jr., P. Netherway, A. L. Juhasz, S. Horner, and A.S. Ball. Science of The Total Environment 1020:181602(2026)

Historic gold mining in Australia produced arsenic-contaminated waste, and Victoria has reported arsenic concentrations up to 47,100 mg/kg in impacted soil. Soil arsenic concentrations above 100 mg/kg in residential soil with garden access require site-specific management and remediation. A 6-month pilot was conducted to investigate P. labillardieri for plant growth and arsenic bioaccumulation under field conditions and assess soil amendment, 5% biosolids biochar (wet weight (w/w)) plus 5% compost (w/w), for optimization. Objectives included quantification of soil characteristics, soil and plant metal(loid) concentrations by acid digestion, arsenic bioaccumulation, and microbial analyses by quantitative polymerase chain reaction. P. labillardieri successfully grew and bioaccumulated arsenic under field conditions with and without the amendment (5% biochar plus 5% compost). The plant-only treatment significantly (p = 0.01) bioaccumulated more arsenic in the roots (∼108 mg/kg) than plant plus amendment (∼55 mg/kg); and had a significantly (p = 0.017) higher bioconcentration factor, demonstrating the plant's potential for phytostabilisation without assistance. A long-term field trial with additional analyses is recommended to validate P. labillardieri and the soil amendment for phytostabilisation of gold mine waste-impacted soil. https://www.sciencedirect.com/science/article/pii/S0048969726002639/pdfft?md5=f04a28e58c681dd5c56e305e1b70a8fc&pid=1-s2.0-S0048969726002639-main.pdf

FRACTIONATION OF CRITICAL METALS FROM AUTHENTIC ACID MINE DRAINAGE USING A MULTI-BED IMMOBILIZED AMINE SORBENT SETUP: A FIELD SITE STUDY [Demonstrations]

Thu, 9 Apr 2026 16:01:32 GMT

Wilfong, W.C., Q. Wang, B. Howard, P. Tinker, K. Johnson, W. Garber, F. Shi, and M.L. Gray.
Journal of Water Process Engineering 58:104788(2024)

A pilot employed a flow-through multi-fixed-bed immobilized amine/silica sorbent strategy to fractionate purified critical metals from authentic acid mine drainage (AMD). DOE's National Energy Technology Laboratory's patented Multi-functional Sorbent Technology sorbents were used to recover critical metals from AMD at the Pittsburgh Botanic Garden. By adjusting the AMD/sorbent ratio, >80% of pure adsorbed Mn (by adsorbed metal weight) and >90% pure adsorbed Al were recovered at lab-scale. Further optimizing the weight hourly space velocity (WHSV) enhanced the rate of adsorbed Al recovery by over 5x, justifying a field site test. After treating >100 L of AMD at the field site, the optimized polyamine/epoxysilane/aminosilane sorbent recovered ~0.7 wt% adsorbed Al at >90% purity. A tangible amount of purified aluminum hydroxide and aluminum sulfate solids was then recovered after eluting and precipitating the previously adsorbed metals.

PROJECT BACKGROUND, DEVELOPMENT AND DESIGN FOR THE LITTLE CONEMAUGH MINE DRAINAGE TREATMENT PLANT PROJECT, CAMBRIA COUNTY, PA [Cleanup News]

Thu, 9 Apr 2026 16:01:11 GMT

Cavazza, E. 27th Annual PA AMR Conference, 14-16 October, State College, PA, 41 minutes, 2025

Drainage from abandoned coal mining operations significantly impacted the Little Conemaugh River Watershed. The Pennsylvania Department of Environmental Protection, in partnership with several other federal, state, and local government entities and non-governmental organizations, began efforts in 2016 to restore the Little Conemaugh River from its headwaters to its confluence with the Stonycreek River in downtown Johnstown, a distance of ~15 stream miles. The effort is focused on the three most upstream major AMD discharges, including the Hughes Borehole, the Sonman Borehole Discharges, and the Miller Shaft Discharge. A restoration goal of biological recovery of the stream to support a recreational fishery was established. The water quality goals include maintaining the stream pH between 6.0 and 9.0, the alkalinity greater than acidity, the total iron <1.5 mg/L, the total aluminum <0.5 mg/L, and the total dissolved solids (TDS) <1,500 mg/L during normal stream flow. Property was purchased to obtain permanent right of way for a large-scale active mine drainage treatment plant (12,000 GPM maximum hydraulic capacity) and for a mine water conveyance and transfer pipeline. The design of the Little Conemaugh Mine Drainage Treatment Plant (LCMDTP) was completed in December 2024. Background information, including details about the abandoned mines, the major discharges (flow and chemistry), and the current design plan and schedule for the LCMDTP, is presented. https://www.youtube.com/watch?v=VYUN_2xS2I0

BLACKLICK CREEK - THE DEATH AND RESURRECTION OF A WATERSHED [Cleanup News]

Thu, 9 Apr 2026 16:00:53 GMT

Smoyer, J. and R. Farabaugh. 27th Annual PA AMR Conference, 14-16 October, State College, PA, 41 minutes, 2025

This presentation reviews the history of coal mining in Vintondale and Wehrum and explains how this history set the stage for the pollution and recovery of Blacklick Creek. The Bureau of Abandoned Mine Reclamation's $28 million acid mine drainage treatment plant, which began running in the spring of 2025, is highlighted along with initial post-treatment water quality data. https://www.youtube.com/watch?v=g1SI4gKEXP4

CENTRAL MINE REMEDIATION: SUCCESS STORY OF CLOSURE OF ANOTHER LEGACY MINE IN MANITOBA [Cleanup News]

Thu, 9 Apr 2026 15:54:55 GMT

Ahmeduzzaman, M., C. Graham, and D. Adedapo. Tailings and Mine Waste 2025 Conference, 2-5 November, Banff, AB, Canada, 16 pp, 2025

The abandoned Central Manitoba Mine (CMM) in Nopiming Provincial Park, Manitoba, posed significant environmental and public safety hazards due to acid-generating tailings, waste rock stockpiles, deteriorated infrastructure, and open mine shafts connected to an extensive underground network. This paper presents the design and implementation of a hybrid capping system engineered to mitigate acid-generating tailings, prevent contamination, and enhance site stability. The design considered a potentially liquefiable foundation, high groundwater conditions, material availability, long-term performance, and constructability challenges. The system incorporated Draintube technology, high-density polyethylene geomembrane liner, and nonwoven geotextile layers to ensure durability and minimize environmental impact. Remediation also included site regrading, tailings encapsulation, concrete capping of mine openings, and debris removal to restore the site. Construction was carefully planned and staged to minimize the risk of tailings liquefaction and prevent the release of tailings downstream. A rigorous quality control and assurance program was implemented to ensure that the remediation work met the design specifications and the vision of all stakeholders. Continuous monitoring and testing were conducted throughout the construction process to verify compliance and optimize material usage. The project was completed ahead of schedule and within budget, demonstrating the effectiveness of innovative engineering design in mine site rehabilitation. The paper highlights the key technical considerations, challenges, and lessons learned, contributing to the ongoing advancement of environmental stewardship and public safety in mine remediation. https://drive.google.com/file/d/1w-7RMt2IOE8SRjA-RF5yYJ9m2Um1mlKE/view

FROM REHABILITATION TO RESTORATION: A 12-YEAR CASE STUDY [Cleanup News]

Thu, 9 Apr 2026 15:54:33 GMT

Haagner, A. and F. van Wyk. Proceedings of the 18th International Conference on Mine Closure, 12 pp, 2025

The development of post‐mining restoration efforts on a platinum mine has been tracked for the past 12 years, and findings have been used to guide the maintenance actions required to sustain ecosystem recovery trajectories. The extensive monitoring framework covers landform recreation, soil hydrology and physics, soil chemistry and microbial activity, vegetation dynamics, and recolonization of rehabilitating sites by birds, mammals, reptiles, and amphibians. The paper shows how the original rehabilitation‐focused planning transformed into a restoration mindset. Shifts in ecosystem resilience following droughts, fires, and intensive grazing, as well as social expectations (the majority of the site is within the Marikana Thornveld vegetation type, recently uplisted to endangered status), required ongoing planning and management responses. The ecosystem responses to post‐disturbance ecological development have shown improving trends across 12 years of monitoring, with stochastic deviations from trends observed for different taxa under varying prevailing conditions. The long‐term nature of the monitoring program allowed for high‐confidence trend analyses that inform restoration planning and maintenance activities. While restoration efforts were not perfectly executed, and external ecosystem stressors have hampered consistent ecosystem development, the case study shows the importance of undertaking rehabilitation and restoration activities within a clear framework that is outcome‐oriented and data‐driven. https://papers.acg.uwa.edu.au/d/2515_94_Haagner/94_Haagner.pdf

SOURCES SOUGHT NOTICE - FISCAL YEAR (FY) 2027 FLORIDA PANHANDLE OPTIMIZED REMEDIATION CONTRACT (ORC) AND MILITARY MUNITIONS RESPONSE PROGRAM (MMRP) (SRCSGT) [Market/Commercialization]

Thu, 9 Apr 2026 15:54:17 GMT

U.S. Army Corps of Engineers, South Atlantic Engineer Division, Mobile, AL
Contract Opportunities on SAM.gov W9127827RA002, 2026

This is a sources sought notice for marketing research purposes only under NAICS code 562910. The U.S. Army Corps of Engineers seeks responses from qualified firms interested in supporting the FY27 Florida Panhandle Group Optimized Remediation Contract (ORC) and Military Munitions Response Program at Eglin Air Force Base, Hurlburt Field, and Tyndall Air Force Base in Florida. The project involves comprehensive environmental remediation services across multiple sites, including investigation, design, construction, operation and maintenance, optimization, and achievement of site-specific performance objectives. The Contractor will support remediation at 59 IRP sites and five MMRP sites across Eglin AFB, Hurlburt Field, and Tyndall AFB, in accordance with applicable regulatory frameworks such as RCRA, CERCLA, and Florida Administrative Code requirements, with oversight primarily from the Florida Department of Environmental Protection and USEPA Region 4. Certain petroleum-contaminated sites will be addressed under state cleanup criteria, and any sites deferred from CERCLA will meet performance objectives with regulatory approval. The effort will be executed as a competitive, firm-fixed-price, definite-delivery contract using a best-value tradeoff approach, with an estimated value of $40 million and a 10-year period of performance consisting of a 5-year base and 5-year option period. The type of set-aside decision(s) to be issued will depend upon the capabilities of the responses to this synopsis. Responses are due by 3:00 PM CDT on April 22, 2026. https://sam.gov/workspace/contract/opp/4bd1855ad8424115afbb78c72739bd7b/view

MISSISSIPPI GROUP OPTIMIZED REMEDIATION CONTRACT AT COLUMBUS AIR FORCE BASE, MISSISSIPPI, KEESLER AIR FORCE BASE, MISSISSIPPI (SOL) [Market/Commercialization]

Thu, 9 Apr 2026 15:53:59 GMT

U.S. Department of the Air Force, Air Force Materiel Command, Installation and Mission Support Center, JBSA Lackland, TX
Contract Opportunities on SAM.gov FA890326R0001, 2026

This is an 8(A) set-aside under NAICS 562910. The U.S. Department of the Air Force requires a contractor to provide environmental remediation activities at Columbus Air Force Base (AFB) and Keesler AFB in Lowndes County in northeastern Mississippi under the Optimized Remediation Contract. The range of activities includes investigation, design, construction of remedial systems, operation and maintenance of established remedies, optimization at applicable sites, and achievement of site-specific objectives. The Contractor shall undertake environmental remediation activities to achieve performance objectives at 17 Installation Restoration Program sites. Offers are due by 2:00 PM CDT on April 16, 2026.
https://sam.gov/workspace/contract/opp/6678c2ec7d0f48429b4bb27b60edd130/view

REQUEST FOR PROPOSAL FOR ENVIRONMENTAL REMEDIATION SERVICES (ERS) SINGLE AWARD TASK ORDER CONTRACT (SATOC) FOR THE SHAW AIR FORCE BASE OPTIMIZED REMEDIATION CONTRACT (ORC) (SOL) [Market/Commercialization]

Thu, 9 Apr 2026 15:53:35 GMT

U.S. Army Corps of Engineers, South Atlantic Engineer Division, Savannah District, Savannah, GA
Contract Opportunities on SAM.gov W912HN26RA009, 2026

This is a total small business set-aside under NAICS code 562910. The U.S. Army Corps of Engineers, South Atlantic Engineer Division, requires a contractor to provide Environmental Remediation Services (ERS) under a $40 million Single-Award Task Order Contract (SATOC) for the Shaw Air Force Base Optimized Remediation Contract. The objective is to achieve site closure for unrestricted residential use in accordance with the installation's RCRA permit. Work includes remediation at 18 Installation Restoration Program (IRP) sites and operation and maintenance of two groundwater treatment plants, with varying performance objectives, including RA-O, IRA-O, LTM, and alternative objectives. The contract will be firm fixed-price with a seven-year ordering period and one six-month option. Offers are due by 2:00 PM EDT on April 24, 2026. https://sam.gov/workspace/contract/opp/22379d5625af434c8910fcdef026e444/view

A STATISTICAL SUMMARY AND VISUALIZATION TOOL FOR 30 YEARS OF BACKGROUND SOIL AND SEDIMENT METALS DATA FROM NORTH CAROLINA SUPERFUND SITES [General News]

Fri, 20 Mar 2026 15:43:40 GMT

Ogwu, M.C., F.M. Nilsen, W.F. Hunneke, L. Norris, R.J. Kelley, P.P. Goodwin, M.A. Nichols, A.R. Van Venrooy, and J.T. Bateson.
Integrated Environmental Assessment and Management 22(1):260-268(2026)

Remediating CERCLA sites is limited to cleanup to levels no lower than background concentrations. However, anthropogenically induced and naturally occurring metal concentrations in soil and sediments often complicate this cleanup process. A statewide dataset of background heavy metal data from Superfund site investigations was compiled to support informed decisions on heavy metal cleanup and the development of soil heavy metal-related policies in North Carolina. The dataset represents background concentrations at 326 Superfund sites found in North Carolina from 1985 to 2015. This 30-year dataset comprises site location data and analytical measurement results for 18 heavy metals in 624 soil and 228 sediment samples, obtained using standard methods. The data are presented in an interactive dashboard, offering summary statistics and graphical representations that can be customized to support specific decision-making needs. The data and dashboard: (1) inform and support cleanup decisions and policy development regarding soil heavy metals, and (2) increase public awareness of the levels of naturally occurring and anthropogenic background heavy metals in soil and sediments across the state. The publicly accessible and interactive dashboard offers a deeper understanding of background environmental conditions in relation to evolving anthropogenic contamination within a broader context.

ADVANCES IN REMEDIATION: PFAS PRECURSORS—DARK MATTER MENACE OR NEGLIGIBLE NOTHINGBURGER? [General News]

Fri, 20 Mar 2026 15:43:25 GMT

Divine, C., T.L. Torralba-Sanchez, T. Blount, T. Guillette, B. Miatke, and J. Lang.
Groundwater Monitoring & Remediation 46(1):10-20(2026)

PFAS precursors can act as a substantial long-term hidden source of regulated PFAAs, yet in many settings, strong sorption, limited mobility, analytical uncertainty, and slow transformation limit their practical impact on site management decisions. While dozens of terminal PFAAs can be measured, they represent only a fraction of the total PFAS mass potentially present. Many can act as precursors capable of converting into PFAAs. Whether hidden " dark matter" precursors are an important long-term driver of plume persistence, or mostly a chemically inert and immobile "nothingburger" locked up in soil pores, is an active debate. Scientific rationale and empirical laboratory and field observations for both perspectives are presented, followed by suggestions for practical considerations for investigation, data analysis, and visualization, conceptual site models, and site management strategies.

MAPPING RESEARCH ON MICROBIAL REMEDIATION OF METALS IN SOIL (2020-2025) [General News]

Fri, 20 Mar 2026 15:43:09 GMT

Usmonkulova, A., M. Pugliese, M. Julie, I. Khalilov, N. Kurbonova, N. Tillyaxodjayeva, R. Karimova, W. Liu, F. Khalilova, and O. Jabborova.
Microbiology Research 17(1):10(2026)

A systematic literature review using bibliometric analysis was conducted to examine the evolution and current trends of biological remediation studies. The bibliometric analysis was used for descriptive, intellectual, social, and conceptual network analyses, while systematic reviews were used to identify the application of biological remediation. A total of 4,835 papers were selected and extracted from Scopus between 2020 and 2025. The publication trends, most influential countries and articles, leading journals, collaboration networks, coupling networks, and application of biological remediation in various disciplines were described. This article highlights new research directions in current bioremediation trends: (1) understanding the interactions between petroleum hydrocarbons and heavy metals in composite pollution systems; (2) exploring microbial community succession during bioremediation; (3) utilizing biosurfactants to enhance contaminant solubilization and biodegradation; and (4) developing integrative, multi-mechanistic remediation approaches. This article is Open Access at https://www.mdpi.com/2036-7481/17/1/10.

THE HIDDEN COSTS OF PFAS REMEDIATION: ENERGY, WASTE, AND LONG-TERM VIABILITY [General News]

Fri, 20 Mar 2026 15:33:34 GMT

Laija, E., Bamer, J., and Molzahn, P. RemPlex Seminar, 2025

This seminar explores the environmental footprint of treating PFAS contamination. Presenters discuss the energy demands, waste generation, and broader environmental impacts of PFAS treatment technologies, offering insights into how these factors, alongside the regulatory context, should shape decision-making around remediation. Attendees gained insights into:

The energy demands and waste generation associated with current PFAS cleanup technologies.

Methodologies for calculating the environmental footprint of remediation strategies.

How treatment technology selection is influenced by both environmental impact and regulatory context.

Emerging perspectives on remedy sustainability and life cycle implications for PFAS remediation.

https://www.pnnl.gov/projects/remplex/seminars/hidden-costs-pfas-remediation?utm_source=chatgpt.com

Slides:https://www.pnnl.gov/sites/default/files/media/file/PDF%20-%20RemPlex-SURF_PFAS_Seminar_8-19-25.pdf

GROUNDWATER CONTAMINATION PLUME STABILITY REVIEW OF ASSESSMENT METHODS [General News]

Fri, 20 Mar 2026 15:33:13 GMT

Contaminated Sites Approved Professional Society (CSAP) Report CA0038290.6960-001-R-Rev1, 55 p, 2024

This review document provides practitioners with a summary of various plume stability assessment techniques, considerations for conducting a plume stability assessment, and examples of plume stability applications. The intended audience for this document is the CSAP Society and contaminated sites practitioners. https://csapsociety.bc.ca/wp-content/uploads/2024-12-03-Groundwater-Plume-Stability-Assessment-Methods-Final.pdf

Presentation on document: https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver_Calgary-2026-%E2%80%93-Joe-Ricker.pdf

MODELING PER- AND POLYFLUOROALKYL SUBSTANCE PRECURSOR TRANSFORMATION IN GROUNDWATER AT A WELL-CHARACTERIZED SITE [Research]

Fri, 20 Mar 2026 15:32:50 GMT

Stockwell, E.B., D.T. Adamson, J.D. Gamlin, P.R. Kulkarni, A. Singh, R.W. Falta, and C.J. Newell. Journal of Contaminant Hydrology 276:104766(2026)

A semi-analytical groundwater model that considers matrix diffusion was calibrated to field PFAS data at a site that contained PFAAs and their respective precursor compounds. The modeling effort considered PFOS, PFOA, PFHxS, and PFBS. Individual precursor compounds were grouped according to their ability to transform into one of four key PFAAs. Model calibration that varied source characteristics, fate and transport parameters, and precursor transformation indicated that precursor transformation could be a critical process for three of the four PFAAs: 40 years after the initial source release ~59%, 84%, and 87% of the PFOA, PFHxS, and PFBS plume maximum concentrations, respectively, originated from precursor transformation. In addition, precursor transformation led to PFOA, PFHxS, and PFBS plumes that were up to 17% longer than if precursor transformation did not occur. In contrast, PFOS was not substantially affected by precursor transformation due to high PFOS concentrations in the source zone compared to its precursors. Additional modeling of complete PFAS source removal indicated that the effects of matrix diffusion, coupled with no natural degradation of certain PFAAs, may result in PFAS plumes at this site that persist and are sustained by precursor transformation. https://www.sciencedirect.com/science/article/pii/S0169772225002712/pdfft?md5=5c4d7ae57b8e251e75e9386e5528d7f2&pid=1-s2.0-S0169772225002712-main.pdf

EVALUATION OF 1,4-DIOXANE NATURAL ATTENUATION AFTER IN SITU PROPANE BIOSPARGING: BENCH-SCALE MICROCOSM TESTS AND FIELD METADATA ANALYSIS [Research]

Fri, 20 Mar 2026 15:32:24 GMT

Antunes, J.M.D., D.K.D. Gaudel, C.H. Bell, Z. Wahl, M. Schnobrich, and M. Li.
Remediation 36(2):e70060(2026)

Bench-scale microcosms were conducted with groundwater collected from seven monitoring wells located along the 1,4-dioxane plumes at two sites where propane biosparging (and bioaugmentation) were previously employed. Over four weeks of incubation, significant 1,4-dioxane removal was observed in microcosms prepared with groundwater samples from four locations within the proximity of historical treatment zones. First-order attenuation rates ranged from 0.02 to 1.11/day, corresponding to half-lives between 0.6 and 32.0 days. Concurrently, a meta study was conducted by compiling groundwater data from > 900 monitoring wells across the U.S. Estimated bulk 1,4-dioxane degradation/attenuation half-lives ranged from 109 to 6,405 days (R² > 0.5). The majority (96%) of the estimated half-lives were < 3,000 days, with the shorter half-lives (i.e., faster rates) generally observed at higher 1,4-dioxane concentrations (i.e., > 20 µg/L). Propane biosparging exhibited significantly shorter half-lives (i.e., a median half-life of 445 days) than MNA and P&T technologies. In addition, 1,4-dioxane half-lives after the start of propane biosparging treatment were an order-of-magnitude shorter than those before treatment, which may also explain the additional orders-of-magnitude decreases in half-lives in MNA-mimicking microcosms. Together, these findings indicate that propane biosparging not only accelerates immediate 1,4 dioxane removal but also "primes" microbial communities for enhanced long term attenuation.

NOVEL REMEDIATION STRATEGIES FOR CR(VI)-CONTAMINATED GROUNDWATER AT LOW TEMPERATURE: STUDY ON THE EFFECTS OF COMBINING ASCORBIC ACID REDUCTION WITH BIOSTIMULATION [Research]

Fri, 20 Mar 2026 15:32:10 GMT

Yang, X., L. Hou, X. Yuan, H. Guo, and F. Ma.
Journal of Environmental Management 403:129156(2026)

Ascorbic acid (AA) combined with molasses was used to remediate Cr(VI) in experiments at 8°C to accelerate the initiation of bioreduction and broaden the applicable range of biostimulation. Results demonstrated that the Cr(VI) reduction efficiency was significantly inhibited by both dissolved oxygen and aquifer media when treated with AA. However, excess addition of AA (n[AA]): n(Cr[VI]) = 2:1) could eliminate the inhibitory effect of non-target reactions. Compared to the molasses-only control, the average removal rates of Cr(VI) in the systems with the additional 38, 86, and 170 mg/L of AA were increased by 0.87, 1.07, and 2.24 mg/(L·d). AA rapidly reduced Cr(VI) within 6 h, and the subsequent bioavailable molasses had the greatest Cr(VI) removal rate [2.47 mg/(L·d)] when the Cr(VI) concentration was decreased to near 40 mg/L. Higher AA additions under combined treatment increased the relative abundance of Bacillus from 26% to 46% and 50%, respectively. In addition, the expression of genes related to Cr(VI) detoxification was upregulated by AA combined with molasses remediation. The expression of ChrA in AA-molasses-amended systems was 1.52 times (38 mg/L AA) and 1.68 times (86 mg/L AA) that of molasses-amended system, respectively. The relative expression of SOD1 in AA-molasses-amended groups was 1.56 (38 mg/L AA) and 1.84 times (86 mg/L AA) that of the molasses-amended system.

TOWARD CLOSED-LOOP REMEDIATION: A DYNAMIC OPTIMIZATION APPROACH FOR HYDRAULIC CONDUCTIVITY ESTIMATION AND PUMP-AND-TREAT DESIGN [Research]

Fri, 20 Mar 2026 15:29:01 GMT

Wei, J., S. Jiang, Q. Liu, X. Zhang, N. Zheng, and J. Xing.
Journal of Contaminant Hydrology 277:104852(2026)

A study proposed a dynamic iterative optimization framework that integrates parameter inversion with remediation plan design into a closed-loop system of simulation-observation-update-optimization. The framework iteratively updates the K-field using pilot point parameterization and simulation-optimization techniques while dynamically adjusting the remediation strategy based on real-time monitoring data. Numerical experiments conducted on a virtual contaminated site demonstrated that the proposed framework significantly improves the accuracy of K-field characterization, as evidenced by decreasing logarithmic root mean square error and increasing spatial correlation coefficient over iterations. When compared with a conventional static remediation plan that is designed once and executed without updates, the dynamic framework achieves a substantially higher contaminant removal rate while simultaneously reducing the total pumping volume. Results highlight the framework's potential to enhance remediation effectiveness and reduce operational costs in heterogeneous aquifers, offering a practical and adaptive solution for complex contaminated site management.

PFAS FATE USING LYSIMETERS DURING DEGRADED SOIL RECLAMATION USING BIOSOLIDS [Research]

Fri, 20 Mar 2026 15:28:45 GMT

Peter, L., M. Modiri-Gharehveran, O. Alvarez-Campos, G.K. Evanylo, and L.S. Lee.
Journal of Environmental Quality 54(1):41-53(2025)

A study investigated PFAS persistence and leaching from biosolids applied to an artificially constructed site to mimic degraded soils. Biosolids and biosolids blended with mulch were applied at different rates to attain either one and five times the agronomic N rate for vegetable crops, and a control treatment with synthetic urea and triple superphosphate fertilizer. Leachates were collected for 2 years from 15-cm depth zero-tension drainage lysimeters. Soils were analyzed post-biosolids application. PFAS were quantified using isotope-dilution, solid-phase extraction, and liquid chromatography tandem mass spectrometry. Leachate profiles exemplified an initial high total PFAS concentration, followed by a sharp decline and subsequent small fluctuations attributed to pre-existing soil conditions and rainfall patterns. Quantifiable PFAS in leachate were proportional to biosolids application rates. Short-chain PFAAs (CF₂ < 6) were dominant in leachate, while the percentage of longer-chain homologues was higher in soils. A 43% biosolids blend with mulch resulted in 21% lower PFAS leachate concentrations, even with the blend application rate being 1.5 times higher than biosolids due to the blend's lower N-content. The blending effect was more pronounced for long-chain perfluoroalkyl sulfonic acids that have a greater retention by soils and the air-water interface. https://acsess.onlinelibrary.wiley.com/doi/epdf/10.1002/jeq2.20576

BENCH MORE, SWEAT LESS: CASE STUDIES USING BENCH-SCALE TESTING TO EXPOSE HIDDEN ISSUES, REFINE REMEDIAL OPTIONS, AND IMPROVE BUDGETING. [Research]

Fri, 20 Mar 2026 15:28:21 GMT

Reichheld, S. | SMART Remediation, 20 January, Vancouver, Canada, 16 slides, 2026

Practical case studies are highlighted where targeted bench-scale testing using site soil and groundwater samples strengthened remedial decisions and improved field outcomes. The case studies show how bench results clarified viable treatment options, narrowed design ranges, and supported more defensible remedial timelines and cost estimates.
https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver-2026-%E2%80%93-Steve-Reichheld.pdf

RESEARCH BRIEF 370: IMPROVING CHEMICAL CLEANUP OF CONTAMINATED GROUNDWATER [Research]

Fri, 20 Mar 2026 15:28:06 GMT

National Institute of Environmental Health Sciences, Superfund Research Program (SRP), February 2026

Researchers from the University of California, Berkeley Superfund Research Program (SRP) Center uncovered how underground conditions influence the success of chemical oxidation-based groundwater cleanup. By considering how contaminants interact with underground particles, the study provides guidance that could help tailor cleanup approaches to site-specific conditions, improving remediation outcomes. https://tools.niehs.nih.gov/srp/researchbriefs/view.cfm?Brief_ID=370

FIELD APPLICATION OF BIOELECTROCHEMICAL REDUCTION TECHNOLOGY FOR TREATING HEXAVALENT CHROMIUM IN GROUNDWATER [Demonstrations]

Fri, 20 Mar 2026 15:27:47 GMT

Li, Y., D. Kong, K. Jin, X. Dong, Q. Zhang, and L. Chen.
Journal of Contaminant Hydrology 276:104744(2026)

A commercialized bioelectrochemical reduction (BECR) technology (E-Redox®-R) was applied at a Cr(VI)-contaminated site in Henan Province, China, to remediate chromium-contaminated groundwater in a pilot study. The BECR pilot system consisted of four units, comprising 12 electrodes installed across a 38.5-m transect. For each unit, one anode well and two cathode wells were arranged in an isosceles triangle configuration, with an inter-electrode spacing of 5.5 m. Within 10 months of system operation, groundwater Cr(VI) concentrations in the cathode wells, ranging from 0.3 mg/L to 46.5 mg/L, decreased by 24% to 99% despite potential masking effects by the desorption of chromium mass from the soil matrix into the aqueous phase. Within the treatment zone, Cr(VI) concentrations in the two upgradient monitoring wells located near the anode electrodes decreased by 21% and 42%, respectively, while concentrations in the three downgradient monitoring-compliance wells near the cathode electrodes decreased by 65% to 96%. Results indicate that the BECR technology can effectively reduce Cr(VI) in the subsurface and holds promise as a sustainable in situ technology for remediating chromium and other contaminants in impacted groundwater.

PILOT-SCALE PERFORMANCE OF A UV-REGENERABLE IRON-BASED ACTIVATED CARBON SYSTEM FOR PHARMACEUTICAL AND PFAS REMOVAL [Demonstrations]

Fri, 20 Mar 2026 15:27:26 GMT

Beak, S., E. Kim, T. Jung, J. Lee, and J. Bae.
Journal of Water Process Engineering 82:109468(2026)

A 200 m³/day pilot was constructed and continuously operated at a municipal wastewater treatment plant (WWTP) in Daegu, South Korea, that coupled iron-impregnated powdered activated carbon (Fe-PAC) with ultraviolet (UV)/ H_₂O_₂ photo-regeneration to restore adsorption in situ. Bench tests verified Fe-site-enabled photo-Fenton reactions. Robustness was pilot-assessed under actual, variable influent fluctuations. Without regeneration, short-chain PFAS (PFHxA and PFHpA) showed limited, unstable removal; long-chain PFNA and PFOA decreased over time owing to site saturation. Most pharmaceuticals (diclofenac and florfenicol) sustained ≥90% removal; hydrophilic caffeine decreased transiently but recovered after regeneration, whereas atenolol exhibited lower long-term stability. With periodic UV/H_₂O_₂ treatment, PFAS removal exceeded 95% after three months; aggregate removal reached 97.7 and 99.1% at three and five months, respectively, without deterioration of water-quality indicators. Fe-PAC acted as a dual adsorbent-catalyst: pores captured contaminants, and Fe sites generated radicals that decomposed surface residues and reopened adsorption sites, providing pilot-scale evidence that the UV-regenerable Fe-PAC hybrid can overcome adsorption limitations and deliver robust control of persistent micropollutants. Optimizing the regeneration frequency and intensity and performing techno-economic evaluations to support full-scale deployment are recommended. https://www.sciencedirect.com/science/article/pii/S2214714426000267/pdfft?md5=4af1b93cb0f7b21df11014da5b0f8b5a&pid=1-s2.0-S2214714426000267-main.pdf

SIMULATOR -TRAINED AI FOR CREATING SUBSURFACE DIGITAL TWINS USING TIME -LAPSE ELECTRICAL RESISTIVITY TOMOGRAPHY DATA [Demonstrations]

Fri, 20 Mar 2026 15:27:14 GMT

Johnson, T.C. | Pacific Northwest National Laboratory RemPlex seminar, 4-6 November, Richland, WA, 21 minutes, 2025

Presenters describe how the hydrogeologic information content implicit in time-lapse electrical resistivity tomography (ERT) data can be extracted and assessed using generative artificial intelligence (AI). The trained AI model generates ensembles of subsurface models that honor field observations, thereby providing a mechanism for assessing uncertainty. The approach was demonstrated at the Hanford 100K-Area in situ soil flushing test, where ERT was used to monitor vadose zone hexavalent chromium remediation through in situ soil flushing.

See times 1 minute-23 minute: https://www.pnnl.gov/projects/remplex/2025-summit/technical-sessions/artificial-intelligence

Slides:https://www.pnnl.gov/sites/default/files/media/file/2025%20RemPlex%20-%20Technical%20Session%208%20-%20Tim%20C.%20Johnson%20-%20Simulator-Trained%20AI.pdf

PFAS VADOSE ZONE MASS DISCHARGE AT AN AFFF-IMPACTED SITE: 1. VALIDATION BASED ON A MULTIPLE LINES-OF-EVIDENCE APPROACH [Demonstrations]

Fri, 20 Mar 2026 15:25:51 GMT

Carey, G.R., D.T. Adamson, R.K. Krebs, M. Rebeiro-Tunstall, K.G. Mumford, B. Guo, G.T. Carey, K. Rooney, and S. Moga. | Remediation 36(2):e70058(2026)

Multiple lines of evidence were evaluated to determine if porewater samples collected during a data gap investigation in the former fire training area (FFTA) at Ellsworth Air Force Base were reproducible and representative. Lines of evidence included supplemental geologic and hydrogeologic data, which showed the presence of a semi-continuous silt/clay layer directly above the water table throughout much of the FFTA, and gravimetric moisture content results that demonstrated vertical water flow at a depth of 15 ft is substantially limited due to semi-arid climatic conditions. Radial diagrams visually demonstrated that there was negligible variability in porewater concentrations caused by varying sample yields in the deep zone. Additional lysimeters installed in the FFTA during the investigation did not result in a significant difference in the estimated vertical mass discharge, which showed that the number of lysimeter sampling points in this area is sufficient. Strong attenuation in PFAS soil concentrations with depth validates the order(s) of magnitude reduction between shallow and deep porewater concentrations observed near the former burn pit. Vadose zone PFAS mass discharge was shown to be 4%-19% of groundwater mass discharge below the water table for regulated constituents. Recommendations for field data collection and estimation of PFAS mass discharge in the vadose zone are presented. https://onlinelibrary.wiley.com/doi/epdf/10.1002/rem.70058

GOING WITH THE FLOW (AND A LITTLE REAGENT): AUGMENTING NATURAL ATTENUATION TO TACKLE A CVOC PLUME [Cleanup News]

Fri, 20 Mar 2026 15:25:33 GMT

Hachborn, E. and B. Loney. | SMART Remediation, 20 January, Vancouver, Canada, 12 slides, 2026

The challenges and outcomes of a complex, multi-year in situ biochemical remediation program designed to address a cVOC groundwater plume at a site in Eastern Ontario are described. The plume originated from a former landfill and had been managed by a P&T system. Following a remedial options analysis and a successful pilot test, the in situ approach was selected as a more targeted method for cVOC mass reduction in the upgradient source area, in addition to phytoremediation downgradient of the plume. A primary challenge was adapting the program to the site's physical constraints and geological conditions. The complex terrain, combined with a necessary 15-meter buffer from an adjacent pond, required a dynamic injection design with variable point spacing and treatment depths to effectively target the main cVOC mass, which was concentrated 1.5 to 2.5 meters above the clay layer. The initial full-scale injection was conducted in early 2020, followed by a second event in late 2023 to maintain performance. The second program was hampered by weather. Low temperatures caused operational delays, affecting equipment like pumps and drill batteries. Site topography and access concerns necessitated the removal of several planned injection points from the program, requiring the redistribution of the remedial reagent to adjacent locations to maintain the target dosage. Despite these challenges, the program achieved its mass reduction objectives. Post-injection monitoring confirmed that the biochemical treatment stimulated the desired degradation of the parent cVOCs, successfully managing the plume so that no further injections are required at this time. It is planned to transition the site to a combined management strategy of monitored natural attenuation along with a recently implemented phytoremediation program to address the residual plume. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Ottawa-2026-%E2%80%93-Hachborn_Loney.pdf

DESIGN CONSIDERATIONS AND IMPLEMENTATION TECHNIQUES FOR IN SITU PFAS SEQUESTRATION USING MODIFIED CLAY [Cleanup News]

Fri, 20 Mar 2026 15:25:14 GMT

Mazzarese, M. | SMART Remediation, 20 January, Vancouver, Canada, 11 slides, 2026

Recent pilot programs have demonstrated that FluoroSorb®, an organically modified bentonite clay (MC), can be injected into overburden to effectively sequester PFAS, offering higher sorption capacity and stability within the subsurface. Independent testing showed that MC exhibited strong sorption kinetics and capacity across a wide PFAS concentration range, with compatibility alongside other remedial amendments. Bench-scale evaluations compared performance against ion exchange resin, granular activated carbon, and biochar, and also assessed competitive sorption in the presence of chlorinated VOCs and petroleum hydrocarbons. Relevant kinetics and co-contaminant performance data are presented. Field deployments in the U.S. and Canada verified injectability and distribution of MC for source-area treatment and PFAS plume interception using direct-push injection. Multiple slurry densities were evaluated to match amendment mass to PFAS loading, including co-injection with calcium polysulfide for simultaneous PFAS and hexavalent chromium treatment. A Canadian PRB installation was monitored for more than a year under continued upgradient PFAS loading, with groundwater results and dye-assisted soil coring confirming amendment distribution, sequestration performance, and durability in situ. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver_Calgary_Toronto_Ottawa-2026-%E2%80%93-Mike-Mazzarese.pdf

OPTIMIZATION TOOLS AND STRATEGIES IMPLEMENTED AT SITES WITH LONG-TERM REMEDIATION SYSTEMS [Cleanup News]

Fri, 20 Mar 2026 15:24:48 GMT

Perlmutter, M. NAVFAC Remediation Innovative Technology Seminar, 116 slides, 2025

This presentation highlights multiple Navy case studies that demonstrate how structured optimization reviews can significantly improve the performance, sustainability, and cost efficiency of long-term remediation systems. Across sites with decades-old remedies, the case studies show that periodic technical evaluation often identifies opportunities to reduce system footprint, modify operating parameters, or transition to alternative remedies while maintaining protectiveness. In several groundwater P&T examples, optimization reviews determined that contaminant mass removal rates had asymptotically declined after years of operation. Through data trend analysis, capture zone evaluation, and influent concentration review, flow rates were reduced, extraction wells were consolidated, and treatment trains were simplified without compromising hydraulic containment. The adjustments reduced energy demand and annual O&M costs while maintaining compliance with cleanup objectives. In some cases, targeted pulsed operation or seasonal pumping strategies were implemented to address rebound concerns more efficiently. Additional case studies involving SVE systems demonstrated diminishing vapor concentrations over time, indicating that systems had reached mass-transfer limitations. Optimization efforts included shutting down low-yield wells, modifying vacuum distribution, and conducting rebound testing to confirm whether active extraction could be terminated. Where appropriate, systems were transitioned to monitored natural attenuation, supported by updated conceptual site models and long-term monitoring plans. The case studies demonstrate that optimization is not a one-time event but an ongoing adaptive management process. By applying data-driven evaluations, refining system operations, and aligning remedies with current site conditions, measurable reductions in operating costs, improved system efficiency, and accelerated progress toward remedial endpoints without sacrificing protectiveness were achieved. https://exwc.navfac.navy.mil/Portals/88/Documents/EXWC/Restoration/er_pdfs/rits/2025/RITS%202025_Optimization_Final.pdf?ver=e6e3gUtUfa83p1xeQTDZ_A%3d%3d

EPA WERRC RFP (COMBINE) [Market/Commercialization]

Fri, 20 Mar 2026 15:19:26 GMT

U.S. Environmental Protection Agency, Region 9 Contracting Office, San Francisco, CA
Contract Opportunities on SAM.go 68HE0926R0002, 2026

This is a full and open competition under NAICS code 541620. EPA Region 9 seeks a contractor to support its Water Emergency Response Resources Contract (WERRC). The purpose of the WERRC is to provide services to EPA and other officials supporting the implementation of EPA's responsibilities under the Clean Water Act and Safe Drinking Water Act. Response activities will support EPA's obligations under the SDWA, CWA, the Stafford Act, as well as any future laws or regulations that establish or expand EPA's response obligations. Work will include Project Planning; General Water Sector Disaster Mitigation; Drinking Water System Response Activities; Wastewater System Response Activities; Analytical Services; Demolition, Restoration, and Soil Stabilization; Provision of Support Facilities to support Water Response/Recovery; Limited Marine/Water Operations; Training; and Logistical Services. The contractor shall support EPA in fulfilling these responsibilities within the region(s) assigned via contract, as well as outside the region on a backup regional response, cross-regional response, and national response. The awarded contract will include a one-year Base Period with four one-Year Option Periods. Questions are due by 5:00 PM on April 1, 2026. Proposals are due by 8:00 PM EDT on April 30, 2026.
https://sam.gov/workspace/contract/opp/92bbc8994cc9430e8d52f69c18c97d6f/view

EV35, NEWPORT, SITE 17, LTM, NORTH RAOMAC (SOL) [Market/Commercialization]

Fri, 20 Mar 2026 15:15:39 GMT

U.S. Department of the Navy, Naval Facilities Engineering Systems Command, Mid-Atlantic Command, Norfolk, VA
Contract Opportunities on SAM.go N4008526R0113, 2026

This is a full and open competition under NAICS code 562910. The Naval Facilities Engineering Systems Command, Mid-Atlantic Command, requires a contractor to perform long-term monitoring and monitored natural attenuation of groundwater at Site 17-NAVSTA Newport in Newport, Rhode Island. The LTM groundwater monitoring well network includes 21 monitoring wells; all wells are sampled biannually. Groundwater monitoring wells selected for sampling are intended to provide sufficient geographic coverage for evaluating MNA parameters and confirming COC concentrations in groundwater. All samples are analyzed for the following: select VOCs - Benzene, PCE, 1,2-DCE, TCE, VC; select metals- arsenic, cadmium, lead, and manganese; PAHs, plus pentachlorophenol PCBs; anions (chloride, N-nitrate, sulfate); and alkalinity. The duration of work under this Contract Task Order shall not exceed 12 months from the award date for the base option and 60 months from award, including option years. Offers are due by 2:00 PM EDT on April 7, 2026. https://sam.gov/workspace/contract/opp/f55fc89f54de47ea9f8e2438c9711e5c/view

SYNOPSIS OF SOLICITATION; FA890326R0019; OPTIMIZED REMEDIATION CONTRACT AT FAIRCHILD AIR FORCE BASE, WASHINGTON (PRESOL) [Market/Commercialization]

Fri, 20 Mar 2026 15:15:21 GMT

U.S. Department of the Air Force, Air Force Materiel Command, AF Installation and Missions Support Center, JBSA Lackland, TX
Contract Opportunities on SAM.go FA890326R0019, 2026

When this solicitation is released, it will be competed as an 8(a) set-aside under NAICS code 562910. The U.S. Department of the Air Force plans to issue a solicitation for environmental remediation activities under an Optimized Remediation Contract at Fairchild Air Force Base. The ORC initiative intends to advance site cleanup during the Period of Performance in the most efficient and cost-effective manner, as supported by a cost-benefit analysis and exit strategy that achieves the greatest reduction in life-cycle cost. The Air Force is interested in a substantial reduction of long-term environmental liabilities and total LCC. These sites have complex attributes that have, to date, inhibited progress toward the achievement of RC. Work will include plan development; Preliminary Assessment/Site Inspection; Remedial Investigation or Remedial Investigation/Feasibility Study, including supplemental investigations; preparation of Decision Documents; and Remedial Action-Operation or Long-Term Management. There is no solicitation at this time. https://sam.gov/workspace/contract/opp/8e17e583381f4a94bd2019faff448f42/view

CERCLA REMOVAL ACTION AT MOJAVE NP (PRESOL) [Market/Commercialization]

Fri, 20 Mar 2026 15:14:49 GMT

U.S. Department of the Interior, National Park Service, Washington Contracting Office, Lakewood, CO
Contract Opportunities on SAM.gov 140P2126Q0049, 2026

When this solicitation is released on or about March 27, 2026, it will be competed as an indian small business economic enterprise (ISBEE) set-aside under NAICS code 562910. The National Park Service plans to issue a solicitation for a Non-Time Critical Removal Action (NTCRA) under CERCLA at the 5-acre Hidden Hill Mine contaminated site within Mojave National Preserve in Southern California. The work includes removing ~69 yd³ of commingled tailings and potentially affected underlying material, based on an assumed thickness of ~1 ft across an area of ~1,850 ft². To account for additional underlying material and soils that may become commingled during excavation activities, a conservative estimate of ~100 yd³ of material will be removed during this Removal Action (RA). Using a conversion factor of 1.5 tons/ yd³, NPS estimates that ~150 tons of material will be excavated, transported, and disposed of as part of the RA. The work also includes preparation of post-award plans, characterizing the material, transporting it to appropriate disposal facility/ies, collecting and analyzing confirmation samples, and preparing a Response Action Completion Report. The estimated removal quantities are based on previous site investigations. The firm-fixed-price contract will use a combination of lump-sum and unit-priced items, subject to the variation in quantity clause in conjunction with an established ceiling and notification requirements. A payment bond (100%), performance bond (100%), and liability insurance will be required prior to contract performance. A group site visit is scheduled at 10:00 AM on April 9, 2026. Pertinent details will be provided in Section L of the solicitation when it is posted. Attendance at the site visit is strongly encouraged. Requests for individual site visits will not be honored. There is no solicitation at this time. https://sam.gov/workspace/contract/opp/423d2b5dab3f40f6b4ce36df85e5bdd0/view