| Site Type: Long Term/National Priorities List (NPL) |
KEEFE ENVIRONMENTAL SERVICES
Map this site in Cleanups in My Community
| Epping,  New Hampshire|
| Rockingham County
| Street Address: ||EXETER RD |
| Zip Code: || 03042 |
| Congressional |
| EPA ID #: ||NHD092059112 |
| Site ID #: ||0101114 |
| Site Aliases: ||KES|
| Site Responsibility: ||Federal, State |
| NPL LISTING HISTORY |
| Proposed Date ||10/23/1981|
| Final Date ||09/08/1983 |
The Keefe Environmental Services site, covering 7 acres in Rockingham County, was operated as a chemical waste storage facility from 1978 until 1981, when the company filed for bankruptcy. Waste storage containers that were present on the site at that time included 4,100 drums, four 5,000-gallon and four 10,000-gallon aboveground storage tanks, and a 700,000-gallon synthetically lined lagoon. Solvents, acids, caustics, heavy metals, paint sludges, waste oils, and organic chemicals were disposed of at the site. Soil and groundwater on and off the site have been contaminated. The site is located in a State-protected watershed with wetland areas draining to the Piscassic River. The site is located in a semi-rural area. There are approximately 12 houses, with a population of approximately 30 people, located along Exeter Road, south of the site. The bedrock aquifer is used as a water supply for ten residences located nearby and is the major source of drinking water for approximately 2,000 people within a 3-mile radius of the site. The Town of New Market has a water supply intake on the Piscassic River, 7 miles downstream from the site.
Threats and Contaminants
The groundwater at the site is contaminated with chlorinated volatile organic compounds (VOCs) including trichloroethene (TCE), perchloroethene (PCE), 1,1-dichloroethene (1,1-DCE), 1,2-dichloroethane (1,2-DCA), 1,4-dioxane and benzene. Soils adjacent to the former lagoon were contaminated before cleanup was completed. Drinking contaminated groundwater poses a potential threat to workers or other future users at the site.
On March 21, 1988, EPA issued a second Record of Decision (ROD) for the groundwater cleanup which included the extraction and treatment via air stripping and carbon adsorption. On June 8, 1990, EPA issued an Explanation of Significant Differences (ESD) for the site, to remove the 1988 ROD requirement for additional treatment utilizing soil vapor extraction. Soil vapor extraction was intended to remove contaminants from shallow soils; however, additional soil sampling indicated lower concentrations than had been expected. An ESD was also written in 2005 to change the groundwater treatment technology from air stripping to a HiPOx system which uses ozone and hydrogen peroxide to reduce contaminant concentrations. The HiPOx system operated both intermittently and full-time from 2005 through 2012, with a two year shutdown/rebound study being performed between 2007 and 2009 and again from 2012 to 2013. In 2009, the extraction system was modified to include additional wells across the site and the HiPOx system was placed back into continuous operation through December 2011. The system was shut down in January 2012 to perform another two year rebound study. At the time of the 2012 shut down, concentrations in the both the influent and effluent met groundwater cleanup levels. A series of tests have been performed over the past few years to better understand natural attenuation mechanisms that may be facilitating cleanup in the Site groundwater. The results of these tests were positive and as a result, the EPA, through NHDES and their contractor, Weston Solutions, are reviewing the feasibility of changing the current groundwater remedy from extraction and treatment to monitored natural attenuation to attain further reduction of contaminant concentrations to drinking water standards.
Response Action Status
|Initial Action ||In 1981, when the site operations ceased, the EPA declared an emergency at the site after determining that the waste lagoon was about to overflow. The EPA and the State initiated emergency actions that included drawing down the lagoon to lessen the threat of a spill. In continuing emergency response actions during 1983 and 1984, the EPA and the State removed more than 4,000 drums, four 5,000-gallon aboveground tanks, and four 10,000-gallon aboveground tanks of hazardous waste. |
|Lagoon ||The actions for cleanup of the lagoon included removing the contents of the lagoon and lagoon liner, and removing the highly contaminated soil adjacent to the lagoon for disposal at a regulated facility. These cleanup activities were completed in 1984. |
|Groundwater ||The groundwater cleanup activities chosen by EPA in the 1988 ROD included: treatment by pumping the contaminated groundwater, filtering volatile contaminants by aerating the groundwater with air, and capturing the airborne chemicals by carbon adsorption. Treated groundwater was to be discharged into a groundwater recharge area adjacent to the wetland along the site border. In 1990, the State completed the design for the groundwater remedy. Construction of the groundwater treatment facility began in 1990 and was completed in the spring of 1993. The treatment system was changed from air stripping to HiPOx (ozone/hydrogen peroxide) to address 1,4-dioxane in 2005. This system operated through January 2012, and groundwater has continued to be monitored to date. |
The Site responsibilities were transferred from EPA to the State in June 2005. EPA and NHDES agreed to shut off the system in January 2012 to perform a two year rebound study, as influent and effluent concentrations were below drinking water standards. During the rebound timeframe, studies were conducted to evaluate the attenuation potential for the contaminants, including 1,4 dioxane to reach drinking water standards through natural mechanisms including adsorption, dispersion and degradation. The results of these studies, conducted by Woodard & Curran, were released in a Technical MNA Evaluation Report in April 2014. The EPA expects to release a feasibility study, which will review a potential change from the current pump and treat groundwater remedy to monitored natural attenuation, the public in late 2015.
|Groundwater - 1,4-Dioxane ||In 2003, a new chemical of concern was detected in the groundwater at the site. This compound, known as 1,4-dioxane, is typically associated with the use of 1,1,1-trichloroethane (TCA) which was also found at the site. EPA and State initiated a full analysis of the groundwater and nearby residential wells in March of 2004 to determine the extent of this contaminant. The compound was not detected in any nearby residential wells. The EPA and State reviewed the groundwater data and determined that a change in the treatment component of the current groundwater treatment system was required. The States contractor, Woodard and Curran, reviewed potential technologies available to treat both the 1,4-dioxane and the other VOCs found in the groundwater at the site. EPA selected a High Pressure Oxidation System which was installed in the Fall of 2004. Operation of this new system was tested through June of 2005 and continued operations of the system as intended, has resulted in a decrease of the overall area and concentration of contaminants. In 2007, the system was shut down to allow EPA and the State to access whether there is any rebound of the groundwater concentrations in the absence of continuous groundwater pump and treat activities. While the system was not operating, groundwater data was being collected (including the nearby residential drinking water wells), to ensure that no adverse response to the shut down is observed. The results of this rebound study were evaluated and released in a report in March 2009. The results indicated that while contaminant concentrations have been reduced across the site, 1,4 dioxane appears to have migrated along natural groundwater flow paths towards the boundaries of the site under non-pumping conditions at levels just above cleanup levels. As a result, NHDES restarted the pump and treat system, adding additional wells to the pumping circuit to try to further reduce the 1,4-dioxane concentrations across the site and added 7 additional wells to monitor boundary conditions. The pump and treat system was started again in March 2009, and operated continuously until it was shut down again in January 2012 for another two year rebound study. At the time of shut down, the treatment plant influent and effluent concentrations were below groundwater cleanup levels; however concentrations in various areas of the plume remained just above cleanup levels. Degradation products for most contaminants are seen in groundwater sampling data, primarily the chlorinated compounds. 1,4-dioxane does not appear to degrade. Concentrations of 1,4-dioxane can attenuate through dispersion and via discharge to surface waters and exposure to sunlight. Very small amounts of 1,4-dioxane were seen in nearby surface waters (small streams) suggesting that some dispersion of the 1,4-dioxane is upward and discharges into these small streams. While primarily found in the overburden, 1,4-dioxane is seen above groundwater cleanup levels in on-site bedrock wells. EPA and NHDES continue to monitor these bedrock wells across the Site and at the boundaries to further understand the 1,4-dioxane migration within the bedrock and ensure that the contamination remains within the approved groundwater management zone. |
|2015 Feasibility Study; Pump and Treat vs Monitored Natural Attenuation ||A Feasibility Study will be developed to review and consider a change from the current pump and treat remedy to natural attenuation to reach drinking water levels within the site groundwater management zone. This report is expected to be available for public review in late 2015. |
|April 7, 2014 Technical MNA Evaluation Report ||Based on the Site’s remedial progress as of 2014, where the residual source concentrations have been reduced, data collected supported a decrease in the overall areal plume extent and there are no adverse impacts associated with MNA effectiveness, such as the accumulation of intermediate compounds in excess of risk-based thresholds, a report was completed which evaluated the feasibility and effectiveness of MNA at the Site through a: (a) Plume stability assessment – verification that the plume is not expanding beyond the GMZ either downgradient or laterally; Cessation of groundwater extraction and treatment – use of forward-looking predictive tools to assess the distribution of contaminants under prolonged system shutdown conditions; (b) Sustainability of MNA processes – evaluation of subsurface conditions and their ability to positively affect the long-term viability of MNA; and (c) Estimation of remedial timeframes – use of statistical tools to assess the time needed to reduce concentrations below cleanup goals. To support the contaminant fate and transport modeling and the detailed MNA evaluations, a “supplemental” MNA evaluation program was also undertaken using a phased approach with molecular biological and stable isotopic tools. The results indicated the potential for the in-situ biodegradation of 1,4-dioxane at the Site and attainment of drinking water criteria in less than 34 years. |
|Results of the 2007-2009 Rebound Study ||The NHDES's contractor, Woodard and Curran, completed a 2+ year rebound study. While the overall VOC mass has been significantly reduced through the pump and treat operation, the relaxation of the water table (under non-pumping conditions) appears to have allowed the most mobile contaminant, 1,4 dioxane to migrate to the site's established boundary as approved in the Groundwater Management Zone (GMZ) permit. In addition, a few bedrock wells which had previously not shown contamination were now indicating low levels of site contaminants and certain monitoring (overburden) wells showed little to no change in concentrations, indicating a concern regarding the current ability of the pump locations to capture and treat some areas of groundwater contamination. Subsequently, EPA and the NHDES determined that the pump and treat system should be placed back in operation and supplemented with additional pumps placed in wells to capture all areas of the plume. The system was back in operation by the end of March 2009. Seven additional wells were installed in January 2010 to continue to monitor the groundwater in the areas it may migrate to under non-pumping conditions. Pump and treat operation continued through December 2011 at which time the system was shut down but left in place while monitoring and additional rebound studies were performed. |
|2005 Transfer of Site Responsibilities from EPA to State (NHDES) ||In June of 2005, the EPA transferred full responsibility for the remainder of the cleanup of the site to the State of New Hampshire. The activities undertaken to complete this transfer, included the removal of the leaching system and contaminated soils from the former lagoon area, the regrading of the former lagoon area, the demolition and disposal of the former drum storage and decontamination pad areas, and the restoration of the wetlands abutting the site. |
|Residential Sampling ||NHDES, and their contractors Woodard and Curran and Weston Solutions, have collected and analyzed nearby residential private wells for Site related contamination since the fall of 2009. There have been no site related contaminants found in any residential well tested. Residential sampling is conducted yearly. Residential Well sampling continued through 2014 and no site related contaminants have been detected. The next round of residential sampling is expected in November 2015. |
|Groundwater Management Zone ||The NHDES established a Groundwater Management Zone (GMZ) around the Site in 2005. Within this zone, groundwater is monitored to ensure that contaminants do not migrate beyond the boundaries and over time, and reach groundwater cleanup levels across the Site. On February 25, 2013, NHDES approved a revision to the 2005 Groundwater Management Zone boundaries to account for: 1) the migration/dispersion of 1,4-dioxane in both the northwest and southeast portions of the Site (under non-pumping natural groundwater flow conditions), and 2) potential consideration by NHDES of a lower 1,4-dioxane groundwater cleanup standard in the future (0.35 ug/l versus the current standard of 3.0 ug/l). |
|Enforcement Highlights||A Consent Agreement was entered into with 119 parties potentially responsible for site contamination in 1986. The EPA filed suit against the non-settling parties in 1989. A Unilateral Administrative Order (UAO) was issued in 1990. In late 1991, the State took over the cleanup of the site from the potentially responsible parties. A final Consent Decree, with approximately 150 potentially responsible parties, was settled in court in late 1992, requiring the parties to perform the selected cleanup actions. |
Construction of all remedy components have been completed at the Keefe Environmental Services site. The potential for direct contact with contaminated soil has been eliminated, and groundwater contamination has been reduced through many years of treatment. In the meantime, groundwater monitoring at the Site (including nearby residential wells) continues.
2008 Five-Year Review: EPA conducted the fourth Five-Year review of the site to ensure that the remedial actions remained protective of human health and the environment and functioning as intended. At the time of this review, the treatment system had been shut down and rebound effects were being evaluated. This Five Year Review was conducted because groundwater concentrations at the site remain above drinking water standards. The review indicated that an evaluation of the need for and the cost effectiveness of restarting the pump and treat system over monitored natural attenuation of the groundwater would be beneficial at this time. While concentrations of VOCs have decreased through extraction and treatment, the effectiveness of continued operation is uncertain. In addition, the 1,4-dioxane concentrations have decreased; however, 1,4-dioxane appeared to have mobilized towards the boundaries of the site just above drinking water standards, indicating a potential need to restart the treatment unit to both reduce the source area concentrations and to provide containment within the existing groundwater management zone (i.e., groundwater institutional control). Exposure pathways that could result in unacceptable risks continued to be monitored both on the site and in residential wells off-site.
2013 Five Year Review: EPA conducted the Fifth Five Year Review of the Site in 2013. At the time of this review, the treatment system was deemed to no longer be cost-effective to continue to operate and had been through two separate shutdown tests as all influent and effluent waters were below drinking water standards; even though the groundwater itself still contained contaminant levels that exceeded drinking water standards. In addition, the ability for natural attenuation mechanisms to reduce these remaining groundwater concentrations to below drinking water standards within a reasonable timeframe was also being reviewed. The review indicated that the remedy continued to be protective of human health and the environment. In particular, the groundwater extraction and treatment associated with the OU-2 remedy and the institutional controls associated with restricting drinking water use continue to protect human health. While ecological clean-up goals have not been established for surface water, it was determined that the levels found in surface water at the Site are below published benchmarks and therefore do not pose ecological risks. Groundwater quality had improved significantly based on systematic decreases in the extent and concentrations of the dissolved phase VOC and 1,4-dioxane plumes. These improvements are attributed to 15 years of effective groundwater capture and system operation, where over 149 million gallons of groundwater were recovered and treated. Collectively the recent MNA evaluations highlight the potential for natural attenuation mechanisms to address the residual contamination within a reasonable timeframe in groundwater at the Site, and in the short -term, the site is protective as potential site exposures are controlled through institutional controls (deed restrictions). In the long-term drinking water standards are expected to be met in groundwater at the Site.
The next Five year Review is due in 2018.
Current Site Status
Groundwater concentrations for VOCs have been significantly reduced by the actions undertaken at the site to date, yet concentrations still remain at levels above health-based standards for drinking water consumption. Groundwater under the site is not currently used for drinking water, but is classified as a potential drinking water source. The principal contaminants of concern in the groundwater are the VOC chlorinated compounds, including 1,1-DCE, 1,2-DCA, benzene, PCE, TCE, 1,1-DCA, and tetrahydrofuran (THF) -- see 1,4-dioxane discussion in next paragraph. The areal extent of the VOC contamination in groundwater has shrunk in size and is now contained underneath and just to the south of the former Keefe operating facility.
EPA and the State are continuing to review groundwater data from the site to determine the extent of 1,4-dioxane in the groundwater. EPA and the State installed a new treatment system which addresses both the VOCs and the 1,4-dioxane found in the groundwater during the Fall of 2004. EPA transferred responsibilities for the site to the State of NH in June of 2005. Activities performed prior to the transfer and documented in the June 2005 ESD included additional soil sampling, decommissioning and dismantlement of wells no longer used at the site, excavation and off-site disposal of contaminated soils in the former lagoon area, demolition and disposal of the former drum storage and decontamination pad areas and wetland restoration measures.
A cost effectiveness evaluation for pump and treat, along with an evaluation regarding the potential for monitored natural attenuation at the site have been conducted. These reports were released in 2009 and again as part of the 2013 Five Year Review. Data collected in the fall of 2011 indicates that, while the concentrations of 1,4 dioxane have been further reduced, concentrations remain at the GMZ boundaries which are above the 3.0 ug/l cleanup level. NHDES expanded the GMZ in February, 2013 towards and just beyond the MW50 series boundary wells, all of which meet the cleanup standards. This established and allowed for the continuing monitoring of the areas northeast and southwest of the Site, where 1,4-dioxane may migrate to under non-pumping conditions. This expansion of the GMZ also allowed for a safety factor to monitor 1,4 dioxane at 0.35 ug/l (versus the cleanup level for 1,4-dioxane of 3.0 ug/l). Monitoring continues to be performed in the spring at the boundary wells and in the fall across the Site to meet monitoring requirements of the Groundwater Management Permit.
Links to Other Site Information
Newsletters & Press Releases:
Federal Register Notices:
Reports and Studies:
|Five Year Review Report, February 22, 1993 (229KB)   |
|Second Five Year Report, September 29, 1997 (800KB)   |
|Third Five Year Report, March 26, 2003 (2,224KB)    |
|Fourth Five Year Review Report, July 31, 2008 (opening file is 28.7MB with links to external PDF files)   |
|Fifth Five Year Review Report, September 9, 2013 (69.8 MB)   |
Harvey-Mitchell Memorial Library, 52 Main Street, Epping, NH 03042
OSRR Records and Information Center, 1st Floor, 5 Post Office Square, Suite 100 (HSC), Boston, MA 02109-3912 (617) 918-1440
|EPA Remedial Project Manager: ||Cheryl Sprague |
|Address: ||EPA New England, Region 1|
5 Post Office Square, Suite 100
Mail Code OSRR07-1
Boston, MA 02109-3912
|Phone #: ||617-918-1244 |
|E-Mail Address: ||email@example.com |
|EPA Community Involvement Coordinator: ||Rodney Elliott |
|Address: ||US Environmental Protection Agency|
New England Regional Laboratory
11 Technology Drive
Chelmsford, MA 01863-243
|Phone #: ||617-918-8372 |
|E-Mail Address: ||firstname.lastname@example.org |
|State Agency Contact: ||Michael Summerlin, PE |
|Address: || NHDES|
29 Hazen Drive, PO Box 95
Concord, NH 03302-0095
|Phone #: ||603-271-3649 |
|E-Mail Address: ||email@example.com |
|Contractor for NHDES ||Vincent DellaRusso, P.G. |
|Address: ||Weston Solutions, Inc|
45 Constiution Ave, Suite 100
Concord, NH 03301
|Phone #: ||1-603-656-5467 |
|E-Mail Address: ||firstname.lastname@example.org |