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

An Introduction to Green and Sustainable Remediation: What, Who, Why, and How, June 10

Posted: May 28, 2015

Provides an introductory overview of Green and Sustainable Remediation that consolidates concepts, definitions, and answers the following questions: What is it? Who does it? Why do it? How to implement it? and, What are the benefits gained? The webinar will also provide resources and case studies to illustrate GSR concepts.

2015 Environmental Measurement Symposium, Chicago, IL, July 12-17, 2015

Posted: May 5, 2015

The 2015 Environmental Measurement Symposium, which is the combined meeting of the Forum on Laboratory Accreditation and the National Environmental Monitoring Conference (NEMC), is co-sponsored by The NELAC Institute (TNI) under a cooperative agreement with the U.S. EPA. Some of the highlights for the week include: a special half-day general session focused on the conference theme; over 160 oral and poster presentations on a variety of cutting-edge environmental monitoring issues; meetings of TNI Committees to further TNI efforts on environmental laboratory accreditation, proficiency testing, and accreditation of field sampling and measurement organizations; an exhibit program showcasing the latest innovations in environmental monitoring; five special keynote presentations on topics of general interest; and an open meeting of U.S. EPA's Environmental Laboratory Advisory Board.

Combining Low-Energy Electrical Resistance Heating With Biotic and Abiotic Reactions for Treatment of Chlorinated Solvent DNAPL Source Areas: ESTCP Cost and Performance Report

Posted: April 23, 2015

This field demonstration combined electrical resistance heating (ERH) with zero-valent iron (ZVI) and in situ bioremediation ( ISB) for TCE treatment in two separate test cells at the East Gate Disposal Yard at Joint Base Lewis-McChord near Tacoma, Washington. The objectives included quantifying the effect of low-energy heating on the extent and rate of contaminant degradation, the impacts on the mass removal rate, relative contributions of biotic and abiotic contaminant degradation mechanisms at different temperatures, and the costs and benefits of applying low-energy heating with in situ treatments.

Integrated Stable Isotope-Reactive Transport Model Approach for Assessment of Chlorinated Solvent Degradation: User's Guide

Posted: April 23, 2015

The objective of this document is to help site managers apply a reactive transport modeling approach for improved compound-specific isotope analysis (CSIA) data interpretation and to estimate more accurate attenuation processes for chlorinated solvents. Quantification of destructive and transport processes and how they contribute to plume size and longevity may help extend monitored natural attenuation remedies to sites previously unable to use them. The report contains a description of standard CSIA laboratory methods, simple data interpretation, and a step-by-step guide to downloading and using software developed as part of this project. The approach presented has benefits over traditional data interpretation, i.e., (1) improvement of a conceptual site models by identification and quantification of prevalent attenuation pathways and identification of secondary inputs from DNAPL dissolution or nondegradative sinks, such as sorption or volatilization, diffusion, or dispersion; (2) a more accurate assessment of degradation of the parent contaminant; (3) and quantitative assessment of the net degradation/accumulation of the dechlorination intermediates.

Waste Discharge Requirements for Pacific Gas and Electric Company Groundwater Remediation Project Agricultural Treatment Units

Posted: May 4, 2015

Phytoremediation systems termed "agriculture treatment units" are in place to treat lower-concentration Cr(VI)-contaminated groundwater and provide for hydraulic control of the plume. Controlled application occurs at over 100 acres of pivot systems where each treatment zone uses a center-pivot drag-drip irrigation system that operates at ~1,400 gal/min, applying it to fields used to grow crops, typically forage crops for livestock such as alfalfa or sudan grass. The toxic, soluble Cr(VI) in the extracted groundwater applied to the fields is chemically reduced in the soils and root zones to the less toxic and insoluble Cr(III), where it remains immobilized. Based on analysis of almost 19 years of monitoring data from the site's agricultural treatment areas, phytoremediation removes, through reduction, ~95% of the Cr(VI) contained in the extracted groundwater. Extracting the groundwater to irrigate crops also provides hydraulic containment to limit the migration of the chromium plume in groundwater. See additional information at PG&E's Hinkley Groundwater Remediation Program website:

In-Situ Solidification of Contaminated Sediments: a Technology Demonstration Project

Posted: May 4, 2015

As an alternative to dredging and capping sediments affected by historical MGP operations, research was performed to determine if full-scale in situ solidification (ISS) and support equipment contained on a barge could solidify tar-contaminated sediments through a column of water using readily available grout components while meeting U.S. EPA performance goals. Project elements included the control of turbidity, pH, and sheen using a dual-turbidity curtain system, and results showed that rigid controls such as steel sheet piling may not be required for good performance. The report covers site characterization and treatability study of the pilot study area; permitting and mobilization; ISS operations in December 2013; sampling and testing; monitoring; pilot costs; and estimated full-scale costs. The primary result of the project was proof of concept that ISS of submerged sediments is achievable and is ready to be tested at a larger scale.

Semiannual Progress Report: Third and Fourth Quarters Fiscal Year 2014 (April 1 to September 30, 2014) for the Lawrence Berkeley National Laboratory Hazardous Waste Facility Permit

Posted: May 19, 2015

Activities conducted by LBNL under its RCRA Corrective Action Program consist primarily of 1) continued operation of the corrective measures approved by the CalEPA's Department of Toxic Substances Control to clean up groundwater affected by TCE and 2) monitoring groundwater quality. The corrective measures required for contaminated soil were completed in 2006. The corrective measures required for groundwater currently are in the operation, maintenance, and monitoring stage. Contaminants include PCE, TCE, and daughter products; metals; PCBs; TPH; and tritium. Treatment consists primarily of in situ soil flushing with groundwater capture. Secondary measures in some areas include subsurface injection of HRC®, soil vapor extraction, and monitored natural attenuation. Extracted VOC-contaminated groundwater is treated using granular activated carbon filters and when not injected into the subsurface to flush the soil is otherwise discharged under permit to the sanitary sewer. During the current reporting period, ~2 million gal of water were treated, with more than 154 million gal treated to date.

Mitigation of PCB Using Permeable Reactive Barrier Technology at Resolution Island, Nunavut From 2005 to 2013

Posted: May 19, 2015

Three permeable reactive barriers (PRBs) at Resolution Island, Nunavut, were installed in 2005 and 2006 to deal with surface runoff of PCBs at the site. These barrier/filter systems are unique in that they are designed to deal with surface sediments as well as surface runoff containing PCBs. This technology was selected because the fractured bedrock at Resolution Island contained soils at PCB concentrations between 1 and 5 ppm (Tier I), between 5 and 49 ppm (Tier II), and ≥50 ppm (CEPA) levels that could not be accessed during excavation. Steep inclines also inhibited access to areas of contaminated soil. Field filter samples showed that partitioning of PCBs between contaminated soil and granular activated carbon filter particles was occurring at levels of 62 ± 11%. This sequestration requires both particle retention within the granular sorptive filters and a maintained contact time between particles for sorption processes to proceed. Eight years after installation, the barriers continue to function very well and are mitigating PCB migration. This presentation describes PRB construction, monitoring results from 2006 to 2013, successful capture of PCB-contaminated sediment, geotextile stability, and plans for decommissioning the barriers.

Vapor Intrusion Guidance

Posted: May 19, 2015

There are two parts to the NC DENR vapor intrusion guidance: the DWM Vapor Intrusion Guidance and the DWM Vapor Intrusion Screening Levels (Apr 2014, 4 pp). To allow for flexibility in updating information on a frequent basis as U.S. EPA revises the Regional Screening Level Tables, the DWM Vapor Intrusion Screening Levels are separate from the main guidance document.