U.S. EPA Contaminated Site Cleanup Information (CLU-IN)

U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division

Recent Additions

FY 2019 Environmental Security Technology Certification Program (ESTCP)

Posted: January 10, 2018

The Department of Defense's (DoD) Environmental Security Technology Certification Program (ESTCP) released a solicitation on January 9, 2018, requesting proposals for demonstrations of environmental and installation energy technologies. Researchers from Federal organizations, universities, and private industry can apply for ESTCP funding. All proposals must respond to a Topic Area associated with the solicitation. ESTCP projects are formal demonstrations in which innovative technologies are rigorously evaluated. ESTCP demonstrations are conducted at DoD facilities and sites to document improved efficiency, reduced liability, improved environmental outcomes, and cost savings. The due date for all pre-proposals is March 8, 2018 by 2:00 p.m. ET.

EPA's 15th Annual People, Prosperity and the Planet (P3) Student Design Competition

Posted: January 4, 2018

This collegiate design competition promotes the use of scientific and engineering principles in creating innovative projects to address challenges and develop real world solutions. This Phase I Request for Applications (RFA) is seeking applications in the research areas of air quality, clean and safe water, land revitalization, and safer chemicals in the marketplace. P3 was developed to foster progress by achieving the mutual goals of improved quality of life, economic prosperity, and protection of the planet - people, prosperity and the planet. EPA's P3 Program offers technical solutions to implement while supporting education in Science, Technology, Engineering and Mathematics (STEM). The P3 program is a two-phase team competition. For the first phase, interdisciplinary student teams submit proposals to compete for $15,000 grants for project ideas addressing environmental solutions. Recipients use the funding to research and develop their design projects during the academic year. In the spring, teams compete for P3 Phase II grant funding of up to $75,000 to implement their projects in a real world setting. The application deadline is February 7, 2018.

Public Comment Period for SW-846 Update VI, Phase III: New Leaching Environmental Assessment Framework (LEAF) Methods and Technical Implementation Guide

Posted: December 21, 2017

This update contains four tests (EPA Methods 1313, 1314, 1315 and 1316), known as the Leaching Environmental Assessment Framework (LEAF) tests, and technical implementation guidance (The LEAF How-To Guide) that evaluate how waste constituent leaching changes with different environmental conditions. The LEAF tests are intended to be more accurate than other leaching tests by assessing constituent leaching potential under actual or plausible disposal conditions. Because the LEAF test methods represent a new approach to evaluating leaching potential, the Agency is developing technical implementation guidance (The LEAF How-To Guide) to help potential users understand the LEAF tests and how to use them. The guidance will also help users interpret the data generated by these tests and provide examples of how the test data can be used for assessing possible constituent release and provide a source term for groundwater fate and transport models used in risk assessment. The LEAF test methods and technical implementation guidance are available for public comment through January 31, 2018.

Faqs Regarding Pfass Associated With Afff Use at U.S. Military Sites

Posted: January 17, 2018

This brief report summarizes the state of knowledge regarding per- and polyfluoroalkyl substances (PFASs) as related to the use and release of aqueous film forming foams (AFFFs) at U.S. military sites. The document addresses eight frequently asked questions about PFASs and provides citations from the literature that offer more detailed information. In addition to describing the unique structural attributes and uses of PFASs in AFFFs, the report identifies other sources of human and environmental exposure, the environmental media in which PFASs are found, and the factors that control PFASs fate and transport. An overview of currently available characterization and remedial tools is provided in addition to information on the pathways of human and ecological health effects.

Bottle Selection and Other Sampling Considerations When Sampling for Per- and Poly-Fluoroalkyl Substances (Pfas) - Revision 1.2

Posted: January 17, 2018

During sample collection, the use of products that contain PFASs could contaminate the samples. While written for a DoD practitioner audience, the information is useful for a broader audience, but is not an EPA guidance document. To prevent accidental contamination of samples, this fact sheet identifies materials to use and materials to avoid.

Characterization and Remediation of Fractured Rock

Posted: January 17, 2018

Contaminated fractured rock sites have often been considered too complex to be remediated, so site managers default to simply containing the contamination. This web-based document provides an introduction to the unique puzzle faced when investigating and remediating fractured rock sites. The guide explains the processes controlling contaminant fate and transport in fractured rock; addresses significant advances in skills, tools, and lessons learned in understanding contaminant flow and transport in fractured rock environments; describes how to develop a useful conceptual site model; and discusses how to identify strategies to remediate contamination in fractured rock.

Steps Needed to Operate and Maintain the Sub-Slab Depressurization System Installed by EPA at the Chem-Fab Property

Posted: February 7, 2018

EPA installed a vapor mitigation system in the main commercial building at 300 N. Broad Street, Doylestown, Pennsylvania (part of the Chem-Fab Superfund Site) in response to the potential for an imminent and substantial endangerment to human health presented by the vaporous migration of benzene and chlorinated VOCs from soils beneath the building into office suites. The system draws sub-slab vapors from beneath the foundation using a system of fans and forces the vapors through PVC pipes into the air outside the building, where the vapors will not concentrate into unacceptable levels as they would in confined office space.

Demonstration and Validation of Enhanced Monitored Natural Recovery at DOD Sites

Posted: February 7, 2018

The performance of enhanced monitored natural recovery (EMNR) as an innovative and cost-effective remedy for legacy sediment contaminants was evaluated under field conditions at the Quantico Marine Corps Base, Quantico, Virginia. The sediments contained DDX (i.e., the sum of the pesticide DDT and it derivatives DDD and DDE). The remedy involved the placement of a thin-layer cap (TLC, commonly <30 cm, also referred to as a "habitat enhancement cap") of clean sand to enhance natural recovery and reduce contaminant bioavailability to benthic organisms and subsequent potential threats to higher trophic levels. While clean sand was used at Quantico Site 99, the caps can include a broader range of clean material, such as clean dredged sediment that meets the chemical criteria for reuse. This demonstration was designed to evaluate the performance and effectiveness of the Quantico EMNR remedy and the utility of available monitoring tools to address EMNR performance, short-term implementation success, projection of long-term remedy success, and understanding of the mechanisms and processes that regulate EMNR effectiveness. Overall performance objectives for cap placement and stability were met.

Cross Validation of Two Partitioning-Based Sampling Approaches in Mesocosms Containing PCB Contaminated Field Sediment, Biota, and Activated Carbon Amendment

Posted: February 7, 2018

This study compared two passive sampling-based approaches—(1) ex situ equilibrium sampling with multiple thicknesses of silicone and (2) in situ pre-equilibrium sampling with LDPE loaded with performance reference compounds—for measuring the bioavailable concentrations of PCBs in contaminated sediments. The study demonstrated that the two methods generated similar results. This information provides environmental managers with the ability to select between these two methods (depending on the circumstances) and know that the results will be comparable.

Advances in Sulfidation of Zerovalent Iron for Water Decontamination

Posted: February 20, 2018

Sulfidation has been shown to improve contaminant sequestration by zero-valent iron (ZVI). This review summarizes developments in ZVI sulfidation by describing the technology's progress through synthesis, characterization, and water remediation and treatment. Under most circumstances, sulfidation can enhance sequestration of various organic compounds and metal(loid)s by ZVI to varying extents. S-ZVI reactivity toward contaminants is strongly dependent on S/Fe molar ratio, sulfidation method, and solution chemistry. Sulfidation also can improve the selectivity of ZVI toward a targeted contaminant over water under anaerobic conditions. This summary includes a description of the mechanisms of sulfidation-induced improvement in contaminant sequestration by ZVI and identifies current knowledge gaps and future research needs of S-ZVI for environmental application.

Co2 Sparging: Phase 3 Full-Scale Implementation and Monitoring Report, Lcp Chemicals Site, Brunswick, Ga

Posted: December 5, 2017

In situ carbon dioxide (CO2) sparging was designed and implemented to address a subsurface caustic brine pool (CBP) formed as a result of releases from historical chlor-alkali manufacturing operations at the LCP Chemicals Site. The remedial action objectives included reducing the pH of the CBP to between 10 and 10.5. Prior to the start of CO2 sparging, the total mercury concentration in the CBP ranged from 35.7 to 2,530 µg/L (mean: 270 µg/L; median: 128 µg/L). By the end of Phase 3, almost every monitoring point (28 out of 30) in the deep Satilla aquifer had lower total Hg compared to pre-sparge levels. Most of the monitoring points (23 out of 30) had total Hg concentrations <20 µg/L. About one-third of all monitoring points had Hg concentrations <2 µg/L. At the end of Phase 3, the average total Hg concentration fell from 270 to 36 µg/L, and the median concentration fell from 128 to 4 µg/L. CO2 sparging was extremely effective in lowering the mean pH in the deep Satilla aquifer from 11.32 (2011-2012) to 7.11. The median pH decreased from 11.44 to 6.57.

Thermal Treatment of Hydrocarbon-Impacted Soils: a Review of Technology Innovation for Sustainable Remediation

Posted: December 5, 2017

The authors review several common thermal treatment technologies for hydrocarbon-contaminated soils, assess their potential environmental impacts, and propose frameworks for sustainable and low-impact deployment based on a holistic consideration of energy and water requirements, ecosystem ecology, and soil science. The review covers thermal desorption in situ and ex situ, smoldering, incineration, pyrolysis, vitrification, radio-frequency heating/microwave heating, hot air injection, and steam injection. Selecting an appropriate thermal treatment depends on the contamination scenario (including the type of hydrocarbons present) and on site-specific considerations such as soil properties, water availability, and the heat sensitivity of contaminated soils. This paper is Open Access at

Environmental Electrokinetics for a Sustainable Subsurface

Posted: December 5, 2017

Many remediation technologies achieve only limited success at sites challenged by low permeability soils, such as silts and clays. Electrokinetics (EK), a soil remediation technique recognized mainly for in situ treatment of low-permeability soils, has been combined with more conventional techniques and can significantly enhance the performance of several remediation technologies, including in situ chemical oxidation, in situ chemical reduction, enhanced in situ bioremediation, and phytoremediation. EK techniques can be used in tandem with conventional remediation techniques to achieve improved remediation performance, and this paper highlights new EK applications that might play a role in sustainable treatment of contaminated sites.

Technical Fact Sheets

Posted: December 5, 2017

In September 2017, EPA released updated technical fact sheets to provide brief summaries of contaminants of concern that present unique issues and challenges at contaminated federal facility sites. Ranging from 6 to 9 pages in length, each fact sheet provides a brief summary of the contaminant's physical and chemical properties, environmental and health impacts, existing federal and state guidelines, and detection and treatment methods. These fact sheets are intended for project managers and field personnel to use when addressing specific contaminants at cleanup sites.
  • Perchlorate — EPA 505-F-17-003
  • Tungsten — EPA 505-F-17-004
  • N-Nitroso-dimethylamine (NDMA) — EPA 505-F-17-005
  • 1,2,3-Trichloropropane (TCP) — EPA 505-F-17-007
  • Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (RDX) — EPA 505-F-17-008
  • 2,4,6-Trinitrotoluene (TNT) — EPA 505-F-17-009
  • Dinitrotoluene (DNT) — EPA 505-F-17-010

Providing Additional Support for MNA by, Including Quantitative Lines of Evidence for Abiotic Degradation and Co-Metabolic Oxidation of Chlorinated Ethylenes

Posted: December 19, 2017

The five sites selected for the ER-201584 demonstration project were Hill AFB OU-10, Hopewell Precision Site, Tooele Army Depot, the former Twin Cites Army Ammunition Plant, and the former Plattsburgh AFB. The objectives were to (1) provide a method to readily and inexpensively acquire the magnetic susceptibility data required to evaluate the abiotic degradation of TCE by magnetite in aquifer materials using existing non-metallic groundwater monitoring wells, and (2) provide a method to readily and inexpensively acquire the data required to evaluate and quantify the rate constant for aerobic biological co-oxidation of TCE. This report shows that an inexpensive downhole sonde (probe) can be used in existing 2- and 4-inch PVC groundwater monitoring wells to quantify magnetic susceptibility of aquifer material. The cost to determine volume magnetic susceptibility in one well using a down-hole sonde was ~$2,000. Additional per-well costs were ~$476 for C-14 assay of the rate constant of TCE cooxidation; ~$1,900 for EAP assay; and ~$835 for qPCR analyses.

Evidence of a Sewer Vapor Transport Pathway at the USEPA Vapor Intrusion Research Duplex

Posted: December 19, 2017

Although previous site remediation efforts have highlighted the importance of sewer lines in transporting VOCs, sewer lines are not routinely sampled during most vapor intrusion investigations, and their role as pathways for vapor intrusion is poorly understood. Results from the tracer study at the USEPA vapor intrusion research duplex (Indianapolis, Ind.) demonstrated the migration of gas from the sewer main line into the duplex. The migration pathway appears to be complex and may include leakage from the sewer lateral at a location below the building foundation. These results combined with results from the prior multi-year study suggest sewer lines should be routinely evaluated as part of vapor intrusion investigations.

Groundwater and Pfas: State of Knowledge and Practice

Posted: December 19, 2017

Beginning in October 2016, 37 scientists and engineers voluntarily collaborated through the National Ground Water Association to develop information on per- and polyfluoroalkyl substances (PFASs) for the broader groundwater community. Using a consensus-driven process that included a public comment period, their efforts were completed toward the end of 2017. NGWA published this PFAS document to assist members and other groundwater professionals who may be tasked with investigating the transport pathways and extent of PFASs in groundwater and surface water, assessing potential risks to receptors, or designing and constructing engineering controls to manage subsurface PFAS contamination. The main purpose of this document is to summarize the current state of knowledge and practice regarding PFAS fate, transport, remediation, and treatment, recognizing that knowledge in this field continues to advance. This document also summarizes current technologies, methods, and field procedures being used to characterize sites and test remediation and treatment technologies. Temporarily available at

Contaminant Flux Reduction Barriers for Managing Difficult-To-Treat Source Zones in Unconsolidated Media: Technical Guidance Manual

Posted: December 19, 2017

The overall objective of this project was to evaluate if inexpensive flow reduction agents delivered via permeation grouting technology could help manage difficult-to-treat chlorinated solvent source zones. The approach aims to provide two benefits for improving groundwater quality at chlorinated VOC sites by (1) physically reducing the mass flux of contaminants leaving the source zone by using permeation grouting, thereby reducing risk and making the downgradient plume more amenable to management by natural attenuation processes; and (2) increasing the natural depletion rate within the source by diverting competing electron acceptors around it to create an enhanced reductive dechlorination zone. This report describes the results of a small-scale demonstration that achieved an average 64% reduction in flow through three small barriers, which was lower than the 90% reduction in flow objective, likely owing to the low permeability of the silty sands in the test area. Applications of one acre in area or more can be significantly less costly than conventional in situ remediation technologies ($996K/acre and $21/yd3 for a 1-acre site). Based on lessons learned during the small-scale demonstration, the process is moderately complex to implement in the field but with no major problems.