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

EPA's 2014-2015 SBIR Phase I Solicitation

Posted: September 19, 2014

The U.S. EPA announces a new closing date of October 9, 2014 for the Small Business Innovation Research (SBIR) Program Solicitation to develop and commercialize new environmental technologies. EPA is one of 11 federal agencies that participate in the SBIR Program as a result of the Small Business Innovation Development Act of 1982. EPA is calling for small businesses to apply for Phase I awards up to $100,000 to demonstrate proof of concept in one of the following topic areas: air and climate, manufacturing, toxic chemicals, water, building materials, food waste, and homeland security. Phase I awardees are eligible to receive Phase II funding, up to $300,000 for two years, through an additional application process.

2015 National Brownfields Training Conference, Chicago, IL, September 2-4, 2015

Posted: September 10, 2014

Your ideas for interactive, insightful, and engaging educational sessions are being sought for Brownfields 2015. Submit your ideas for educational sessions tailored to encourage conversations and participation from attendees. The conference planning committee is looking for ideas in the following topic areas/tracks: Moving Forward: How Do We Get from Ideas and Plans to Assessment and Cleanup; Heavy Lifting: Leveraging Available Financing to Spur Brownfields Redevelopment; Put on Your Marketing Hat: Real Estate and Development; Planning for a Better Environment; Working Toward a Sustainable Future; Making a Visible Difference in Communities; Worry Beads: How to address Liability and Avoid Enforcement; Launching a New Era of State, Tribal, and Local Partnerships.

Groundwater Statistics Tool

Posted: September 1, 2014

The Groundwater Statistics Tool is designed to help evaluate contaminant of concern (COC) concentrations on a well-by-well basis to determine whether a groundwater restoration remedial action is complete. The tool is designed to support the U.S. Environmental Protection Agency (EPA) memorandum "Guidance for Evaluating Completion of Groundwater Restoration Remedial Actions" (OSWER 9355.0-129) and comports with principles outlined in the "Recommended Approach for Evaluating Completion of Groundwater Restoration Remedial Actions" (OSWER 9283.1-44).

Summer 2014 Technology News and Trends

Posted: September 1, 2014

This issue highlights characterization and remediation strategies to address contaminants of emerging concern (CECs), which are chemicals or materials characterized by a perceived, potential, or real threat to human health or the environment or by a lack of published health standards. CECs typically are associated with certain classes of products, as ingredients or generated during processing or manufacturing, such as pharmaceuticals and personal care items, steroids and hormones, and pesticides. A contaminant also may be "emerging" due to the discovery of a new exposure pathway to humans, such as vapor intrusion into buildings, or the development of a more stringent regulatory standard. New toxicity information on frequent contaminants such as trichloroethylene (TCE) and tetrachloroethylene (PCE), for example, can lead to re-emergence of concern

Soil Flushing: a Review of the Origin of Efficiency Variability

Posted: September 2, 2014

Soil flushing using aqueous solutions is employed to solubilize contaminants. As water solubility is the controlling mechanism of dissolution, additives (e.g., surfactants, cosolvents) are used to enhance efficiencies and reduce the treatment time over the use of water alone. Although surfactant alone gives efficiencies of 80-85% in lab experiments, the amount of product required for successful field application may not be economically sustainable. The literature indicates that soil flushing efficiency can vary from 0% to almost 100% in the field, which illuminates the importance of knowledge concerning the site characteristics and contaminant location, amount, and behavior as well as other factors. The importance of the initial saturation of the NAPL is highlighted: the higher the initial saturation, the higher the efficiency. For initial saturations lower than 1%, soil flushing may be an inefficient technique. This paper provides an overview of recent lab, pilot, and field studies of soil and groundwater remediation, with a focus on chlorinated solvents.

Flux-Based Criteria for Management of Groundwater

Posted: September 2, 2014

This report reviews guidance, documents, tools, and industry practice relating to the application of mass flux-based criteria for the management of groundwater contamination. It attempts to define where further work should be carried out to realize the advantages of mass flux-based assessment of groundwater contamination and to identify the most reliable and promising methods for further research and application. Although the focus of this report is on Australian regulations and practice, its findings and recommendations can be expected to have general applicability. The focus here is on mass flux and mass discharge associated with groundwater contamination in the dissolved phase; only brief consideration is given to the use of mass flux relative to free-phase transport.

Use of Compound-Specific Stable Isotope Analysis to Distinguish Between Vapor Intrusion and Indoor Sources of VOCs: User's Guide for CSIA Protocol

Posted: September 2, 2014

Compound-specific stable isotope analysis (CSIA) can be used as a building-specific vapor intrusion investigation tool to augment data from other investigation methods. Its primary utility is to provide an independent line of evidence to distinguish between vapor intrusion and indoor sources of VOCs. This CSIA protocol involves collection of subsurface source (i.e., groundwater) and indoor air samples. Concentrations of target VOCs from these media must be known or estimated to develop CSIA sampling parameters (e.g., sample collection time). This document describes the applicability of CSIA for vapor intrusion investigations, provides a step-by-step procedure for sample collection, and offers guidelines for data interpretation.

Contaminated Sediments Remediation: Remedy Selection for Contaminated Sediments

Posted: September 2, 2014

General categories of contaminated sediment remedial technologies covered in this document include monitored natural recovery and enhanced monitored natural recovery, in situ treatment, capping (conventional and amended), and removal (dredging and excavation). Additional factors to consider as part of the evaluation process are summarized (e.g., feasibility, cost, stakeholder and local governments concerns). This text was developed in two different formats:

Explanation of Significant Differences for the St. Maries Creosote Site, St. Maries, Idaho

Posted: September 23, 2014

Soil, groundwater, and sediment in the St. Joe River are contaminated with creosote released from a wood treater that operated on the site from 1939 to 1960. The ROD used concentrations of PAHs in sediment as the sole factor in determining which sediments required cleanup. With this ESD, EPA approved an approach for delineating the sediment area requiring cleanup that includes sediment chemistry as a primary factor, but also considers several other lines of evidence to develop a map delineating specific areas and depths where sediment will be removed from the river. As required in the ROD, contaminated sediment will be dredged and removed from the river, dredged areas will be backfilled with clean imported material, and a temporary watertight sheet pile wall will be used to enclose the most highly contaminated sediments during cleanup. Owing to the shallow depth to groundwater, EPA is changing the depth of soil that will be excavated and treated via thermal remediation in the upland area from 20 ft to a nominal depth of 10 ft. Soils deeper than 10 ft now will be included in the area to be solidified in place. EPA also is revising the soil cleanup number for benzene from 0.002 mg/kg to 1.1 mg/kg.

In Situ Thermal Treatment at the Groveland Wells Superfund Site, Groveland, Massachusetts: Cost and Performance Summary Report

Posted: September 23, 2014

Following issuance in 2007 of an Explanation of Significant Differences for Operable Unit 02 at the Groveland Wells Nos. 1 & 2 Superfund site, installation and operation of an in situ thermal treatment (ISTT) and enhanced soil vapor extraction (SVE) system began in August 2010. The ISTT system applied the use of electrical resistance heating—the Electro-Thermal Dynamic Stripping Process, or ET-DSP™—in the vadose and saturated zones. Ancillary equipment necessary for ET-DSP™ implementation included a transformer to deliver power to the system, power distribution systems, water-circulation units to supply water to the electrodes, water injection and cable lines for the ET-DSP™ system, and an emergency power source for the SVE system. The ISTT system operated from August 2010 to February 2011. Steam-enhanced heating was incorporated in December 2010 to supplement the ISTT's heating capability to account for heating difficulties attributed to highly permeable geology and high resistivity areas. Although soil and groundwater confirmatory sampling results indicated a 97% reduction of TCE in the site groundwater, concentrations of TCE and cis-1,2-DCE remained above cleanup goals in two small areas below pavement. The ISTT system was shut down in February 2011. The estimated overall cost of the ISTT remedial action was $6,264,000.

Transferable Training Modules On Environmental Science

Posted: September 23, 2014

The University of Arizona Superfund Research Program has developed a transferable training module series that currently features arsenic, environmental toxicology, and pesticides. The educational modules were developed for use by community health workers. The flexible nature of the modules allows them to be adapted for any audience. Individual sections are available to read on line or to download in PDF files. Each theme (Arsenic, Environmental Toxicology, and Pesticides) also contains a PowerPoint presentation that can be downloaded and modified as needed. All contents are available in English and Spanish.

U.S. EPA Region 4 Technical Services Section Issue Paper for Polychlorinated Biphenyl Characterization at Region 4 Superfund and RCRA Sites: Technical Services Section Issue

Posted: September 23, 2014

This issue paper provides Region 4 project managers, on-scene coordinators, and technical staff with a recommended approach for evaluating and characterizing PCBs in groundwater, surface water, soil, and sediment to support defensible and protective remedy selection at PCB-contaminated sites. Characterization of groundwater, soil, and sediment for PCBs is unique because of the varied site conceptual models for PCB and PCB mixture migration and the specific analytical requirements to evaluate the presence and extent of PCB contamination. A high percentage of cases at sites where PCB groundwater contamination is present found the contamination to result from facilitated transport associated with solvents, colloids, or emulsions. The facilitated transport mechanism calls for consideration of issues such as sampling techniques, turbidity, and the presence of elevated carbon. Determining site cleanup strategies and risk is influenced by the processes, material types, and site hydrogeologic settings present at the site. This document helps the site project manager begin the process of planning the site characterization using appropriate analytical procedures on adequate samples, with the endpoint being that defensible data are available to support sound decision-making at complicated PCB-contaminated sites.

An Injectable Apatite Permeable Reactive Barrier for in Situ 90Sr Immobilization

Posted: August 20, 2014

An injectable permeable reactive barrier (PRB) technology was developed at DOE's Hanford facility to sequester Sr-90 in groundwater through the in situ formation of calcium-phosphate mineral phases, specifically apatite, which incorporates Sr-90 into the chemical structure. The development approach included bench-scale experiments, an initial pilot-scale field test, and in 2008 the emplacement of a 300-ft PRB at treatability-test scale. The apatite amendment formulation uses two separate precursor solutions, one containing a Ca-citrate complex and the other a Na-phosphate solution, to form apatite precipitate in situ. Citrate is needed to keep calcium in solution long enough to achieve a more uniform and areally extensive distribution of precipitate formation. The 300-ft PRB was installed on the downgradient edge of a Sr-90 plume beneath the Hanford site to reduce Sr-90 flux discharging to the Columbia River. Monitoring data collected to date indicate that the barrier is meeting treatment objectives (i.e., 90% reduction in Sr-90 concentration) and continues to meet remedial objectives more than four years after installation. See additional details in report DOE/RL-2013-22:

Determination of Polychlorinated Biphenyls (PCBs) in Sediment and Biota

Posted: August 20, 2014

The determination of PCBs in sediment and biota generally involves extraction with organic solvents, cleanup, and gas chromatographic separation with electron capture detection or mass spectrometry. Due to the low concentrations of non-ortho-substituted PCBs compared to those of other PCBs, their determination may require an additional separation step. All stages of the procedure are susceptible to insufficient recovery and/or contamination; therefore, quality control procedures are important to check method performance.