Site Description

The SRSNE Site is located on approximately 14 acres of land along Lazy Lane in Southington, Hartford County, Connecticut, approximately 15 miles southwest of the City of Hartford. The SRSNE facility began operations in Southington in 1955. From approximately 1955 until the facility’s closure in 1991, spent solvents were received from customers and distilled (recycled) to remove impurities, and the recovered solvents were returned to the customer or sold to others for reuse.

Significant milestones recently achieved on the SRSNE project:

  • EPA approved the Institutional Control Plan on April 30, 2018. This started the process to implement required ICs. June 15,2018 – EPA approved the final Construction Completion Report (for the RCRA C Cap component of the remedy).
  • July 23, 2018 – Shut down the NTCRA 1 (“source area”) extraction wells that have been operating since 1995. The combination of in-situ thermal and ongoing natural attenuation resulted in more than an order of magnitude reduction in influent VOC concentrations, to the point pumping is no longer needed. As part of the RCRA cap construction, we installed a gravel trench system and valves through the sheet pile wall to allow gravity flow of groundwater that would no longer be pumped – this water will eventually be removed with the down gradient, long-term pumping wells installed in 1998 as “NTCRA 2”. Identification of per-fluorinated compounds led to a full-scale pilot study using liquid granular activated carbon that was placed in the gravel trenches this week. We opened the valves and started gravity flow on July 26, 2018.

Key milestones in the history of the Site, are as follows:

  • 1983: USEPA adds the Site to the Superfund list; SRSNE signs a consent decree with USEPA to install a groundwater recovery system and store/manage hazardous waste on site.
  • 1983-1988: USEPA and the State of Connecticut take enforcement action to require cleanup of the facility operations and the property.
  • 1991: SRSNE operations cease.
  • 1990: USEPA initiates the Remedial Investigation for the Site, conducting three phases of investigation that are presented in a four-volume report (HNUS 1994).
  • 1992: USEPA conducts a Time-Critical Removal Action to remove contaminated soils from the railroad grade drainage ditch and to remove some chemicals stored at the property to an off-site location.
  • 1994: USEPA and the SRSNE Site Group enter into an Administrative Order on Consent (AOC) for Removal Action to construct and operate a pump and treat system to contain the principally contaminated overburden groundwater (the Non-Time-Critical Removal Action # 1 or “NTCRA” work). Other work conducted under this AOC included the construction of a mitigation wetland in the northeast corner of the Cianci Property, implementation of a full-scale phytoremediation study within the NTCRA 1 sheet pile wall, and extension of public water to three buildings adjacent to the Site.
  • NTCRA 1 100% Design
  • 1998 EPA “Cost and Performance Report” on NTCRA 1
  • 1995: USEPA issues an Action Memorandum for a second NTCRA (NTCRA 2) to hydraulically contain VOC-impacted bedrock groundwater downgradient of the NTCRA 1 system.
  • 1996: USEPA and the SRSNE Site Group enter into a second AOC for Removal Action and Remedial Investigation/Feasibility study to expand the groundwater containment system and complete site investigations. Work under this AOC resulted in the completion of the Site RI/FS, implementation of NTCRA 2, and the decontamination, demolition and removal of the remaining buildings and tanks from the Operations Area.
  • 1995 – Present: SRSNE Site Group operates groundwater containment and treatment
  • 1996 – 2004: SRSNE Site Group completes remedial investigations and conducts feasibility studies.
  • 2005: USEPA issues the proposed remedial action plan in June and holds two public meetings; the public comment period runs from June through August.
  • 2005: USEPA issues the Record of Decision (ROD) for the Site, which describes the final remedy – key elements include:
    • Treating waste oils and solvents in subsurface by heating (“in-situ thermal treatment”)
    • Excavating, consolidating, capping impacted soil and wetland soil onsite
    • Continuing to pump and treat groundwater in the overburden and bedrock aquifers, and continue monitoring groundwater outside the capture zone to verify natural recovery.
    • Placing restrictions on use of Site property and groundwater.
    • Carrying out long-term monitoring of cap and groundwater.
    • Record of Decision
  • 2008: USEPA signs CD with SRSNE Site Group to perform Site-wide cleanup and complete the RD/RA activities, CD lodged with the Court
  • 2009: Court enters CD, Remedial Design Work initiated
  • 2009: 1st Annual State of Compliance Report
  • 2010: 1st Five Year Review Report
  • 2010: USEPA, CTDEEP & SRSNE Site Group host Open House for public to learn about upcoming remedial activities.
  • 2010: USEPA issues Remedial Design Work Plan approval.
  • 2010: USEPA issues approval of PIPP 100% Design RAWP.
  • 2010: Initiated Pre-In Situ Thermal Remediation (ISTR) Preparation Plan construction activities.
  • 2010: 2nd Annual State of Compliance Report
  • 2011: ISTR Conceptual Design approval.
  • 2011: Approval of ISTR 100% Wellfield Design.
  • 2011: 3rd Annual State of Compliance Report
  • 2011: Completed Pre-ISTR Preparation Plan construction activities.
  • 2012: 4th Annual State of Compliance Report
  • 2013: Install In-Situ Thermal Remediation wellfield and system; 5th Annual State of Compliance Report
  • 2014: 6th Annual State of Compliance Report
  • 2015: Performed Second Five-Year Review (needs link to documents), In-Situ Thermal Remediation Completed and Designed cap system
  • 2016: Install cap, start design of long-term groundwater treatment system – Final RCRA CAP 100% RD and RAWP Report; 7th Annual State of Compliance Report
  • 2017: 8th Annual State of Compliance Report