| Site Type: Long Term/National Priorities List (NPL) |
Map this site in Cleanups in My Community
| Londonderry,  New Hampshire|
| Rockingham County
| Street Address: ||RTE 102 |
| Zip Code: || 03053 |
| Congressional |
| EPA ID #: ||NHD062004569 |
| Site ID #: ||0101106 |
| Site Aliases: |
| Site Responsibility: ||Federal, State, Potentially Responsible Parties |
| NPL LISTING HISTORY |
| Proposed Date ||12/30/1982|
| Final Date ||09/08/1983 |
The Tinkham Garage site covers approximately 375 acres in Londonderry, NH. During 1978 and 1979, oil, oily wastes, washings from septic tank trucks, and other substances were discharged at the site. In 1978, residents complained of foam and odors in a small unnamed brook, which prompted an investigation. This investigation revealed that improper waste disposal had occurred. The State ordered the site owner to prevent further degradation of the surface water and groundwater in the area. In early 1983, drinking water wells at the Londonderry Green Apartment complex and several other private supply wells were closed due to contamination, and residents were provided access to a municipal water supply. A majority of the site includes wooded land and open fields; however, a Home Depot and Staples were constructed on the northeast corner of the property in 2003 followed by construction of a residential development (165 active senior housing units) over the center of the site. Currently, there are also approximately 400 people who reside within a condominium complex on the western boundary of the site, as well as several private, single family homes to the north. Surrounding the Site are private residential homes to the northeast and west and commercial properties along route 102 to the North.
Threats and Contaminants
Volatile organic compounds (VOCs) were identified in the surface water and groundwater on-site and in areas adjacent to the site. The soils located in the field behind the Tinkham Garage site and in two condominium complex leachfields also contained VOC contamination. A potential threat to residents may exist if the contaminated groundwater were to be used as a drinking water source.
Initial Actions and long-term cleanup efforts are being utilized at this site.
Response Action Status
|Initial Action ||The State issued a health order in early 1983, advising residents not to drink their well water. Bottled water was initially provided until a municipal water supply line was installed and began operating in the fall of 1983. |
|Entire Site -- 1986 ROD ||The cleanup approach selected in the 1986 Record of Decision (ROD) for the site included: on-site treatment of contaminated soils by vacuum extraction; backfilling, regrading, and revegetating source areas after contaminated soils have been excavated; extraction and off-site treatment of contaminated groundwater at the Town of Derry's wastewater treatment works, which required on-site pre-treatment; and groundwater monitoring on- and off-site.|
Design activities were completed in 1994 and soil cleanup began in early 1994. The groundwater cleanup began in late 1994, following the construction of a municipal sewer line between the site and the Town of Derry wastewater treatment plant. The soil cleanup was completed in late 1995. Pre-treatment was eliminated from the groundwater cleanup in late 1995 as contaminant levels continued to drop. Groundwater pumping from the former (bedrock) condominium water supply wells was suspended in 2001. An Explanation of Significant Differences (ESD) was finalized in 2003 which called for groundwater monitoring to continue until drinking water standards are obtained through natural attenuation processes. A five year review was completed in the spring of 2004 and a Reuse Assessment was completed in September 2004. The third five year review was completed in March 2009 and the fourth five year review was completed in September 2014.
|Fractured-Bedrock Evaluation, Tinkham Garage Site, Londonderry, New Hampshire, Haley & Aldrich, October 24, 2014 ||The third five year review noted that while the remedy remained protective, the monitoring program for groundwater was not sufficient to monitor protectiveness primarily due to the construction of many of the wells with large open bore holes. As a result bedrock investigations were undertaken in 2014 which indicated that levels as high as 760 ug/l of 1,4 dioxane, as well as other chlorinated compounds and their degradation products are present within individual fractures down gradient of the former source area behind the Tinkham Garage. The data collected supports previous conclusions regarding contaminant distribution, wherein well FW11D is in an aquifer recharge area and located near and downgradient of the source, and FW21D is located downgradient near the former condominium supply well and within an aquifer discharge area, and that higher contaminant concentrations are found in the regional zone of conductive bedrock fractures which extends between these two wells, along a NE/SW strike. It is currently understood that under both pumping and ambient conditions, the majority of the water will be produced from fractures between 70 and 110 feet or more below the ground surface and that the current highest concentrations of total VOCs and 1, 4-dioxane were also generally found in fractures at depths between 70 and 110 feet below ground surface. At this time, the bedrock investigation has not extend deeper at these locations. |
|Enforcement Highlights||The potentially responsible parties, under a Consent Decree, agreed to undertake the design and cleanup of the site. This site is closely associated with the Gilson Road (Sylvester), Plymouth Harbor, and Cannon Engineering NPL sites. |
All construction at the site is complete. The provision of an alternate drinking water source to residential properties found to be impacted in 1983 has reduced potential for exposure to contamination at the Tinkham Garage site and protected public health while cleanup activities were being completed. Contaminated soil from the two leach fields and the soil pile have been removed from the condominium area and cleaned up along with soils in the garage area.
Current Site Status
EPA issued a comfort letter to Home Depot on October 31, 2000, and Home Depot began construction of a large retail building in December 2000 on the northeast corner of the site. A Staples was constructed adjacent to the Home Depot in 2003. During 2002, groundwater monitoring continued and EPA began preparing an Explanation of Significant Differences (ESD) to change the remedy from active pump and treatment to natural attenuation of the groundwater to achieve cleanup levels. This second ESD was finalized in 2003. Construction of the 165 unit residential retirement development began on the site in January, 2004. A renewed Groundwater Management Zone (GMZ) permit was approved by the State of NH in November 2007 and again in 2012 to ensure that the existing groundwater institutional controls remain in place until cleanup levels are achieved. In May of 2008, at the request of NHDES, a new contaminant was monitored for in groundwater. Results indicated that 1,4 dioxane is present throughout the site at levels greater than the NH groundwater drinking water requirement (AGQS) of 3 ug/l. The Third 5-Year Review for the site was completed in March 2009, and the fourth five year review was completed in September 2014. Groundwater monitoring conducted since 2003 has indicated that biodegradation of chlorinated VOCs is occurring within groundwater at the Site and that there has been an overall decrease in total VOCs.
The third five year review noted that while the remedy remained protective, the monitoring program for groundwater was not sufficient to monitor protectiveness primarily due to the construction of many of the wells with large open bore holes. As a result, a preliminary bedrock investigation was undertaken in 2014 which indicated that levels as high as 760 ug/l of 1,4 dioxane, as well as other chlorinated compounds and their degradation products are present within individual fractures down gradient of the former source area behind the Tinkham Garage. The bedrock fracture scope and assessment, prepared by Haley & Aldrich, is summarized in a report titled “Fractured-Bedrock Evaluation, Tinkham Garage Site, Londonderry, New Hampshire,” dated October 24, 2014. The data collected supports previous conclusions regarding contaminant distribution, wherein the higher contaminant concentrations are found in the regional zone of conductive bedrock fractures along a NE/SW strike. It is currently understood that under both pumping and ambient conditions, the majority of the water will be produced from fractures between 70 and 110 feet or more below the ground surface and that the current highest concentrations of total VOCs and 1, 4-dioxane were also generally found in fractures at depths between 70 and 110 feet below ground surface. At the time, this preliminary bedrock investigation did not extended deeper at these locations.
In December 2014, EPA was notified by the NHDES MtBe Bureau that, as part of their investigations across the State, contaminants were identified in residential drinking water wells near the Site very similar to those found within and down gradient of the source area (including 1,4-dioxane). As a result, over the next few months additional testing was conducted by NHDES where residential well impacts were found to be greater than drinking water standards, In addition, NHDES contracted with SecondWind for installation of Point-of-Entry treatment systems to remove contaminants prior to residential use. However, because of its chemical properties, 1,4 dioxane is not readily treated by these systems and many homes were then also offered bottled water as well. EPA is expected to release a third ESD later in 2015 which will allow for impacted and potentially impacted homes to be connected to the nearby waterline. Additional bedrock Investigations are also expected to continue through 2016 at the Site.
Construction of the Residential Retirement Development on the Tinkham Garage Superfund Site.
Links to Other Site Information
Newsletters & Press Releases:
Federal Register Notices:
Reports and Studies:
|Supplement to Explanation of Significant Differences (ESD), Operable Unit (OU) 1 Administrative Record (AR) Index, January 21, 1992, (470 KB)   |
|Amended Record of Decision (ROD) Administrative Record (AR) Index, Operable Unit (OU) 1, March 10, 1989, (565 KB)   |
|Explanation of Significant Differences (ESD) Administrative Record (AR) Index, Operable Unit (OU) 1, March 31, 2003, (574 KB)   |
Leach Library, 276 Mammoth Road, Londonderry, NH 03053
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: ||US Environmental Protection Agency|
5 Post Office Square, Suite 100
Mail Code: OSRR07-1
Boston, MA 02109-3912
|Phone #: ||617-918-1244 |
|E-Mail Address: ||firstname.lastname@example.org |
|EPA Community Involvement Coordinator: ||Rodney Elliott |
|Address: ||US Environmental Protection Agency|
New England Regional Laboratory
11 Technology Drive
Chelmsford, MA 01863-2431
|Phone #: ||617-918-8372 |
|E-Mail Address: ||email@example.com |
|State Agency Contact: ||Kenneth Richards |
|Address: ||P.O. Box 95|
Concord, NH 03302-0095
|Phone #: ||603-271-4060 |
|E-Mail Address: ||firstname.lastname@example.org |