Mohan, R., M. Reemts, P. Gupta, R. Galloway, T. Johnson, R. Brown, and T. Donegan.
10th International Conference on the Remediation and Management of Contaminated Sediments, 11-14 February, New Orleans, Louisiana, 27 slides, 2019

The LCP Chemicals Superfund Site consists of a mix of tidal creeks, marshes, and brackish estuary and an adjacent upland area. Site contaminants of concern include mercury, Aroclor 1268, lead, and PAHs. In spring 2018, a pilot project was completed to test placement methods and the layer's remedy performance in preparation for a larger remedy implementation. Sand and higher organic content fines were tested as placement materials. Primary placement occurred using a hydraulic nozzle spray method that resulted in generally uniform distribution and thickness of the cover. A mat-based access road was installed to allow equipment to move the pipeline and spray nozzle within the pilot marsh area. The study successfully placed 6-12 inches of material within a 2/3-acre marsh area. A 30- to 45-degree spray yielded the best distribution of materials. Placement of sandy material was faster and more uniform than fines due to the enhanced settling characteristics and ease of distribution of the material. A modified topsoil-fines mix with a baffle plate eventually permitted optimal placement of fines within the study area while keeping target organic content. Material thickness is expected to be sufficient to encourage natural vegetative recovery over a time span of 2 to 3 years. Vegetative monitoring will be conducted over a period of 2 years to document natural recovery and thin cover effectiveness for the remedy. https://www.battelle.org/docs/default-source/conference-proceedings/2019-sediments-conference-proceedings/c5.-restoration-and-revitalization-strategies/c5_1210_-180_mohan.pdf?sfvrsn=7d82143f_2 See 6 month post-pilot screening summary: https://semspub.epa.gov/work/04/11115324.pdf.