| Site Type: Long Term/National Priorities List (NPL) |
Map this site in Cleanups in My Community
| Greenland; North Hampton,  New Hampshire|
| Rockingham County
| Street Address: ||480 BREAKFAST HILL RD |
| Zip Code: || 03840, 03862 |
| Congressional |
| EPA ID #: ||NHD064424153 |
| Site ID #: ||0101107 |
| Site Aliases: |
| Site Responsibility: ||Federal, State, Potentially Responsible Parties |
| NPL LISTING HISTORY |
| Proposed Date ||01/15/1984|
| Final Date ||06/01/1986 |
The privately owned Coakley Landfill site is a 92-acre parcel of land that was operated by several municipalities. The landfill area encompasses 27 acres in the southern portion of the site. The site accepted municipal and industrial wastes from the Portsmouth area between 1972 and 1982. Incinerator residue was also accepted from the incineration recovery plant for the Refuse to Energy Project between 1982 and 1985. The primary source of contamination is the landfill itself. Volatile organic compounds (VOCs) and metals are the predominant contaminants found. On- and off-site surface water and groundwater are contaminated. The site is located on a groundwater/surface water divide, and residential wells to the south, southeast, and northeast of the landfill are contaminated with low levels of VOCs. Public water service has been extended to the areas with contaminated wells by the local communities. There are several small commercial facilities and restaurants nearby.
Threats and Contaminants
On-site groundwater is contaminated with arsenic, phenol, methyl ethyl ketones, and 1,4-dioxane; off-site groundwater is contaminated with heavy metals including arsenic, chromium, lead, and VOCs including benzene, 1,4-dioxane, tetrahydrofuran, and methyl ethyl ketones. On-site soil and sediments are contaminated with arsenic and lead. Stream sediments contain contaminants such as arsenic and VOCs. Leachate contamination at the site includes VOCs, tetrahydrofuran, and ketones. Metals and VOCs were detected in nearby wetlands. Potential use of the groundwater as a water supply is the main threat to human health.
Removal and Remedial Actions (involving source control and management of migration).
Response Action Status
|Initial Action ||In 1989, North Hampton extended a municipal water supply line to residents who had been obtaining their water from 13 private wells contaminated with VOCs. The State set up a residential well monitoring program with an early warning system to detect any groundwater contamination in the area. Local residents now have access to municipal water or other uncontaminated groundwater supplies. |
|Source Control ||Source Control is Operable Unit 1 (OU-1) of the remedy. The state conducted an investigation from 1986 to 1987. The goals of the field work were to characterize the hydrogeologic conditions at the site, including an estimate of the total area of the landfill and soil deposits, details of the hydraulic properties of bedrock and selected surface streams, and the identity of pathways for contaminant migration from the site. The state completed the study in 1990. Based on the results of the study, a cleanup remedy was selected in a June 1990 Record of Decision (ROD) that included consolidating approximately 2,000 cubic yards of wetland sediments; consolidating approximately 30,000 cubic yards of on-site solid waste; fencing and capping the landfill; collecting and treating landfill gases by thermal destruction; extracting groundwater and treating it with a combination of chemical, biological, and physical processes; and establishing long-term monitoring and institutional controls. Construction of the cap was completed during the summer of 1998. Passive collection and venting of landfill gases was allowed through the issuance of an Explanation of Significant Differences (ESD) in 1996. An ESD was issued in 1999 and documented the determination that leachate collection and treatment was not needed. Another ESD was issued in 2007 which documented that the Safe Drinking Water Act Maximum Contaminant Level for arsenic was changed from 0.05 mg/l to 0.010 mg/l, introduced tetrahydrofuran as an additional chemical of concern, and documented the EPA Health Advisory for Manganese changed from 0.18 mg/l to 0.3 mg/l. |
The Coakley Landfill Group (CLG) installed methane gas alarms in buildings on abutting properties in 2007 and no violations have been reported on those properties since that time. From September 21, 2006 to the present, no methane has been detected above the state standard for methane soil gas (2.5%) at three of the six gas monitoring probes (M-2, M-4, and M-5). For the other three monitoring probes (M-1, M-6, and M-7), sporadic exceedances have been observed. The CLG continues to monitor landfill gas under the oversight of EPA and NHDES.
In 2008 and 2009 additional sediment and surface water samples, respectively, were collected and toxicity tests were run, which showed no significant ecological impact. Since the sampled area was selected as the “worst case area” based on chemistry testing, EPA concluded that it is likely there are no significant ecological impacts in surface water and sediment at the Site. This was documented in July 29, 2009 as an Addendum to the Second 5 Year Review. In 2010, the CLG performed annual chemistry testing of the sediment, surface water and leachate samples and performed a statistical analysis of all the historical data, which ensured that the currently non-toxic concentrations do not show an upward trend.
|Management of Groundwater Migration ||Management of Groundwater Migration is Operable Unit 2 (OU-2) of the remedy. The EPA began a study in 1990 of the migration of contaminants into off-site groundwater and the ecological effects of the site contamination on adjacent wetlands. In the fall of 1994, the groundwater component of the remedy was documented in a second ROD that included imposing institutional controls to prevent the use of contaminated groundwater, allowing groundwater to clean itself through natural attenuation, and long-term monitoring. Negotiations with the potentially responsible parties to undertake the off-site groundwater remedy were successfully completed in 1998. The parties also put institutional controls in place and are presently conducting environmental monitoring on an annual and semi-annual basis. |
An ESD, issued in 2007 documented that the Safe Drinking Water Act Maximum Contaminant Level for arsenic was changed from 0.05 mg/l to 0.010 mg/l, and the EPA Health Advisory for Manganese changed from 0.18 mg/l to 0.3 mg/l.
In 2008, NHDES approved a Groundwater Management Permit (GMP) application submitted by the Coakley Landfill Group (CLG). With this approval, a Groundwater Management Zone (GMZ) was established. The GMZ delineates the area around the landfill in which contaminated groundwater is being monitored. Properties within the GMZ have either deed restrictions or easements in place to further prevent exposure to the groundwater and/or tampering with the ongoing remedy.
|Enforcement Highlights||The state issued a Consent Order in 1983 requiring the owner to accept only incinerator ash from the Refuse to Energy Project. A Consent Decree was issued in 1992 by which 30 parties agreed to design, construct, and operate the source control remedy. A second Consent Decree was issued in 1999 whereby 28 parties agreed to implement the remedy for management of groundwater. |
Findings from the last Five Year Review (September 2011) suggested that concentrations may exceed the site-specific interim cleanup levels (ICLs) beyond the current GMZ boundary. Thus, additional tests were performed to evaluate the need for expansion of the GMZ and the need for additional Institutional Controls. Those tests concluded that there was a need for expanding the GMZ further to the north and that four additional monitoring wells were needed to be installed within this GMZ extension. The GMZ was formally expanded on January 7, 2014 with NHDES approval of a Groundwater Management Permit Renewal Application.
The provision of an alternate drinking water supply has reduced the potential for exposure to groundwater contamination. Since completion of the landfill cap in 1998, groundwater flow has been generally to the west of the landfill, and contamination levels have been slowly declining (especially for VOCs). However recent studies have shown that this western flow of groundwater is eventually diverted partly to the southwest towards the brook known as Little River, and partly to the north/northeast, along the valley of Berry's Brook. This new knowledge about the groundwater flow, the detection of trace amounts (< 1 ppb) of 1,4-dioxane at residential properties north/northeast of the GMZ expansion, and potential new development in that area, has prompted EPA to recommend an extension of the current drinking water supply and the implementation of additional land use restrictions in the areas directly north and northeast of the GMZ.
Current Site Status
Since the agency issued its 1990 source control cleanup plan and its 1994 groundwater cleanup plan for the Coakley Landfill Superfund site, the acceptable level of arsenic in drinking water, aka Maximum Contaminant Level (MCL) has changed from 0.05 mg/l to 0.010 mg/l. The agency changed the arsenic performance standard for the Coakley site to match this new MCL. Additionally, a manganese Health Advisory was issued in 2004 which uses the guidance level of 0.3 mg/l which is now being used for the site. Additionally, since these cleanup plans were issued, the state of New Hampshire has updated its environmental regulations. For the source control cleanup plan, the chemical tetrahydrofuran has been added as an additional chemical of concern because groundwater monitoring detected this contaminant at levels exceeding state standards. These changes have been documented in ESDs issued September 2007 for the source control (OU-1) cleanup and the groundwater (OU-2) cleanup. In 2008 the potentially responsible parties put groundwater institutional controls in place and continue to monitor the groundwater quality at the site on an annual basis until cleanup levels for all contaminants of concern are met.
The most recent, September 2011 Five Year Review concluded that: [o]verall, the remedy at the Coakley Landfill Superfund Site currently protects human health and the environment in the short-term. Long-term protectiveness has also been achieved at OU-1 based on continued maintenance of the landfill cap, long-term monitoring, and use restrictions being in-place. Long-term protectiveness will also be achieved at OU-2 when interim groundwater cleanup levels for all contaminants of concern are met and restrictions on the use of groundwater within OU-2 can be removed. Monitoring of the site will continue until cleanup levels for all contaminants of concern are met.
All the issues described in the 2011 Five Year Review report have been fully resolved except one. Namely, the preparation of an ESD to formally add 1,4-dioxane as a contaminant of concern (COC). EPA is currently working on the issuance of this ESD which in addition will document the specific steps that will be taken to prevent further migration of contaminated groundwater from the landfill and human exposures to it, among other measures. The ESD is expected to be issued for public comment in either February or March 2015.
Final Landfill Cap
View of the landfill capped area in 2011 from the access road past the entrance gate, looking to the South-West
Detailed view of the rip-rap on top of the drainage swale at the Northwest corner of the landfill, looking to the South (2011)
Links to Other Site Information
Newsletters & Press Releases:
Federal Register Notices:
Reports and Studies:
|Administrative Record Index, OU 01 Record of Decision (ROD), June 28, 1990 (990 KB)   |
|Administrative Record Index, Explanation of Significant Differences (ESD) for Operable Unit (OU) 1, March 22, 1991 (461 KB)    |
|Administrative Record Index, Operable Unit (OU) 01 Fourth and OU 2 Fifth Explanation of Significant Differences (ESD), September 28, 2007 (264 KB)   |
|Administrative Record (AR) Index, Operable Unit (OU) 1 Explanation of Significant Differences (ESD), May 17, 1996 (468 KB)   |
|View Records of Decision (RODS) on-line (EPA HQ)   |
|Fourth Explanation of Significant Differences (ESD) for Operable Unit 1, September 28, 2007 (1.43 MB)   |
|Explanation of Significant Differences (ESD) for Operable Unit 2, September 28, 2007 (1.49 MB)   |
|Second Explanation of Significant Differences, OU2, July 01, 2009 (1.12 MB)   |
|Re-Issued Fourth Explanation of Significant Differences, OU1, July 01, 2009 (1.32 MB)   |
|Institutional Controls for this Site   |
North Hampton Public Library, 237-A Atlantic Avenue, North Hampton, NH 03862
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: ||Gerardo Millan-Ramos |
|Address: ||US Environmental Protection Agency|
5 Post Office Square, Suite 100
Mail Code OSRR07-1
Boston, MA 02109-3912
|Phone #: ||617-918-1377 |
|E-Mail Address: ||firstname.lastname@example.org |
|EPA Community Involvement Coordinator: ||Rudy Brown |
|Address: ||US Environmental Protection Agency|
5 Post Office Square, Suite 100
Mail Code ORA01-1
Boston, MA 02109-3912
|Phone #: ||617-918-1031 |
|E-Mail Address: ||email@example.com |
|State Agency Contact: ||Andrew J. Hoffman |
|Address: ||New Hampshire Department of Environmental Services|
PO Box 95, 6 Hazen Drive
Concord, NH 03302-0095
|Phone #: ||603-271-6778 |
|E-Mail Address: ||firstname.lastname@example.org |