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

Petroleum Vapor Intrusion: Fundamentals of Screening, Investigation, and Management

Posted: October 30, 2014

Petroleum Vapor Intrusion (PVI) is the process by which volatile petroleum hydrocarbons (PHCs) released as vapors from light nonaqueous phase liquids (LNAPL), petroleum-contaminated soils, or petroleum-contaminated groundwater migrate through the vadose zone and into overlying buildings. This Interstate Technology & Regulatory Council (ITRC) guidance document uses a scientifically-based approach to support improved decision making at potential petroleum vapor intrusion (PVI) sites by employing an eight-step process. By applying this approach, decision makers can confidently screen out sites, and therefore focus limited resources on the small fraction of petroleum-contaminated sites that warrant vapor control or additional site management. This ITRC guidance complements the ongoing work of U.S. EPA Office of Underground Storage Tanks (OUST) in addressing the PVI pathway.

Funding Available for 2015 Brownfields Assessment and Cleanup Grants

Posted: October 22, 2014

These brownfields grants may be used to address sites contaminated by petroleum and hazardous substances, pollutants, or contaminants (including hazardous substances co-mingled with petroleum). Opportunities for funding are as follows: Brownfields Assessment Grants (each funded up to $200,000 over three years; Assessment Coalitions are funded up to $600,000 over three years) and Brownfields Cleanup Grants (each funded up to $200,000 over three years). Please note that applicants who received an Assessment grant from EPA in Fiscal Year 2014 (FY14) are eligible to apply under this competition. If the applicant was a member of a coalition that was awarded a grant in FY14, that applicant is also eligible to apply under this assessment competition. The proposal submission deadline is December 19, 2014.

Design and Construction Issues at Hazardous Waste Sites, Philadelphia, PA, April 15-17, 2015

Posted: October 9, 2014

The applications of engineering and science associated with cleaning up hazardous waste sites continue to evolve rapidly. The goal of this symposium is to facilitate an interactive engagement between professionals from government and the private sector related to relevant and topical issues affecting our field. Abstracts are being accepted through November 21, 2014 in the following topic areas: project management, technology, lessons learned and case studies, and new approaches for hazardous waste cleanups.

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.

Vapor Intrusion From Entrapped NAPL Sources and Groundwater Plumes: Process Understanding and Improved Modeling Tools for Pathway Assessment

Posted: October 2, 2014

Mechanisms controlling vapor generation and subsequent migration through the subsurface in naturally heterogeneous subsurface under different physical and climatic conditions were investigated using lab and modeling studies alongside the development of new modeling tools. Dynamic and complex subsurface vapor pathways sometimes contribute to counterintuitive cause-effect relationships. Infiltration affects vapor signals in indoor air, with the time scales and the strength of the vapor signals depending on the interplay of the intensity, duration of rainfall, and subsurface heterogeneity. Water table fluctuation imparts very complex transport behavior within the capillary fringe, which has significant effects on vapor loading from the groundwater plumes. Trapped sources in the unsaturated zone are capable of loading significant mass into the unsaturated zone, but the loading rate is a strong function of the moisture distribution in the vicinity of the source. Indoor sampling strategies need to factor in the transients associated with climate and weather.

Simulation Program i-SVOC User's Guide

Posted: October 2, 2014

The i-SVOC simulation program estimates the emissions, transport, and sorption of semivolatile organic compounds in the indoor environment as functions of time when a series of initial conditions is given. This program implements a framework for dynamic modeling of indoor SVOCs and covers six types of indoor compartments: air (gas phase), air (particle phase), sources, sinks (i.e., sorption by interior surfaces), contaminant barriers, and settled dust. Potential applications of this program include (1) use as a stand-alone simulation program to obtain information that the current equilibrium models cannot provide, including evaluation of the effectiveness of pollution mitigation methods such as variable ventilation rates, source removal, and source encapsulation; (2) reducing the uncertainties in the existing multimedia models; and (3) use as a front-end component for stochastic exposure models to provide information about the SVOC distribution in indoor media in the absence of experimental data. This program is intended for advanced users who are involved in and familiar with indoor environmental quality modeling or indoor exposure assessment.

Remediation of Contaminated Groundwater Using Permeable Reactive Barriers (RESET)

Posted: October 20, 2014

The long-term performance of a pilot-scale PRB installed at the Orivesi (Finland) field site has been monitored since summer 2006. The dimensions of the granular iron PRB were designed on the basis of lab experiments to ensure the removal of chlorinated solvents (PCE, TCE, and their degradation products) released to the subsurface by a dry cleaner. The system has a funnel-and-gate configuration with an additional control well. In the Orivesi project, traditional open pit and cleat-supported excavation techniques were essentially the only available earthwork methods for barrier installation. The fracture zones in bedrock were filled with injection material to eliminate contaminated groundwater bypass below the PRB.

Petroleum Vapor Intrusion: Fundamentals of Screening, Investigation, and Management

Posted: October 20, 2014

This document presents a method of screening petroleum-contaminated sites for potential vapor intrusion (VI) and provides tools and strategies for evaluating the VI pathway at different types of petroleum sites. The screening method is based on the "vertical screening distance," which was developed using empirical data from hundreds of petroleum-contaminated sites. Using screening distance to assess petroleum-contaminated sites allows managers to focus scarce resources on sites with greater potential for petroleum vapor intrusion (PVI). The guide provides a detailed description of the differences between PVI and chlorinated VI and then describes an eight-step process for screening, investigating, and managing sites contaminated with petroleum hydrocarbons to address the PVI pathway. View the guide as a Web-based document or open/download it as a PDF file at