The site is located at 140 Roosevelt Drive in Derby Connecticut the Hull Dye and Print industrial complex.
On August 25, 1994, USEPA received a call from the Connecticut Department of Environmental Protection (DEP), requesting access to the Oil Spill Liability Trust Fund in order to conduct removal actions to prevent the continuing discharge of oil to the Housatonic River from the 140 Roosevelt Drive facility.
The responding EPA OSC opened FPN # 014504 and with the National Pollution Fund Center (NPFC) Case Officer, prepared a Pollution Removal Funding Authorization (PRFA) which was issued to the DEP to initiate cleanup operations. Subsequent activities included the removal of oil saturated sediment and approximately 10,000 gallons of free product and the installation of an oil recovery well system. This system (Derby-1) is still operating and recovering oil on an intermittent basis.
On August 20, 1999, DEP received a new report of an oil sheen on the river, apparently emanating from the tailrace of the facility. Removal operations to recover oil from the source area began on December 6, 1999 with the installation of an oil recovery system (Derby-2) consisting of five recovery wells within an interceptor trench. Although the wells are continuously recovering subsurface oil, there has still been significant sheening emanating from the tailrace. Hard containment boom and sorbent boom, which is changed out on a regular basis, are used to contain the oil from reaching the river.
An up-gradient canal dating back to the late 1800’s has been feeding water to the facility to power electric producing turbines. The turbines have been off-line for a number of years due to the ongoing oil issues, but the water has continued to leak from the canal and through the facility due to a compromised gate system. Since a sudden water release from the canal appears to be the cause of a significant oil discharge to the river in late March, 2006 and the continuous flow of water may be routinely picking up subsurface oil, a decision was made to cut off the flow from the canal to the turbines and eventually the tailrace. In late May, a subcontractor to EPA’s prime contractor mobilized to the site and began the installation of a temporary dam in the canal, upstream of the facility. When the dam was in place, the down gradient section of the canal was allowed to drain and crews proceeded to seal up the pipes that have been draining the canal water. Steel plates were fabricated and then bolted and welded to the flanges of two, 8’ diameter pipes. Three other pipes/culverts that may have also allowed water to drain from the canal through the facility were either flanged or framed and filled with concrete. When these activities were completed, the dam was removed and the canal allowed to re-fill.
As part of the treatment train for groundwater being pumped out of the ground (to assist in oil recovery from the Derby-2 system), the water is pumped through a series of carbon vessels. Two vessels are used at any given time while a third is kept available as a backup. In April, 2006, one of the vessels was found to be leaking and kept off-line. In late June, 2006, a second vessel developed small leaks, effectively shutting down the system. EPA’s contractors will be replacing the vessels in the near future.
EPA is currently exploring ways to tap into other source areas and more effectively retain the oil prior to it reaching the tailrace and the adjacent river. The next step will be to proceed with exploratory borings from within the interior of the building. If substantial pools of oil are encountered, the borings will be converted to oil recovery wells.
Long range plans still include damming of the tailrace which will block any continuing flow of oil from the race into the river. Options to recover the oil from the dammed area are being examined and may include backfilling the race in back of the dam and installing another oil recovery well and if necessary, a groundwater treatment system.
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