State Superfund Program

The Higganum Cove Site consists of 12.8 acres, 9.9 of which are tidal wetlands along Higganum Creek, just west of the Connecticut River. It had been used since the 1840s for fabric and yarn dyeing, the production of bridge netting, marine paints, and mimeograph paper. The last occupant of the site went out of business in 1983 and fire destroyed the former mill building in 1989. The owner hired a contractor to recover brick and metal, but the contractor illegally filled part of the on-site wetlands with demolition debris, household garbage, and possibly hazardous waste.  DEP issued and Order requiring the owner to investigate and remediate that pollution, but they did not comply. In 1995, the site entered the State Superfund Program. Site investigations found coal tars, metals, petroleum, and PCBs.

DEEP, EPA, and Town of Haddam began collaborating on this project in 2014 and EPA excavated approximately 8,400 tons of polluted fill.  Wetlands and uplands were restored by planting trees, native plants, and hydroseeding wetland areas to prevent repopulation by invasive species. The site is now being used for passive recreation and hiking trails.

The J. Swift Chemical Company recycled solvents in the 1950s and 1960s at a small facility on Route 44. Waste solvent sludges were buried at the site and pollution from a variety of chlorinated and non-chlorinated solvents is present on the site. In the early 1980s, DEP spent over $1M to extend public water to serve affected and potentially affected properties, along with emergency removal of polluted soil and drums.

Potential risks to neighboring properties from solvent vapors were identified and a system was installed to prevent vapors from entering a residence in 2007.  Vapor intrusion measures have been installed on neighboring properties by the developers of those properties.  In 2013 the site was reassessed and remediation of the remaining solvent contamination at the site had been estimated to cost $4.4 million.

The McDonough Expeditionary Learning School, which was built in 1897, and the J.P. Harbison Playground are located at the intersection of Wilson Street and Hillside Avenue in Hartford. The site had been used for the disposal of incinerator ash, bricks, and cinders before the school was constructed. The former disposal areas are located beneath and to the north end of the school building. In 1995, the City requested DEP's help with the construction of an addition to the northern end of the school. A total of 314 soil samples were analyzed for arsenic, cadmium, lead and semi-volatile organic compounds. Ash and contaminated soils were removed for proper disposal before construction began.

Beginning around 1835, the property was used as a grist mill, a saw mill, a tannery, a woolen mill, a machine shop, a coal gas manufacturing plant, and a warehouse. From 1954 to 1967, Hamilton Standard manufactured printed circuit boards there, using electroplating, chemical etching, photographic development, and parts washing using chlorinated solvents. From 1968 to 1977, it was a boron filament manufacturing plant. In 1986 the property was sold and then a fire destroyed many of the mill buildings. A commercial complex and residential condominiums were developed in the former mill buildings that had survived the fire.

Investigation for pollution began in 1993. In 2003, DEP and Hamilton entered into a Consent Order to clean up the site, including State funding of up to $3.9M for pollution that pre-dated Hamilton's use of the site. In 2004, Hamilton bought the condos and ended residential use.  Excavation of pollution on the eastern portion of the site was completed in 2006. Soil and groundwater polluted with chromium and chlorinated solvents were treated and an engineered control was installed over ash and coal pollution along the banks of Broad Brook.

Additional information is posted on the EPA Broad Brook Mill webpage.

The Mitral Corporation manufactured metal stamping products and generated spent degreasing solvents, waste oil, and scrap metal.  In 1988 DEP discovered a septic leaching field had failed, causing sanitary and industrial wastewater to be discharged to the ground surface, drums that were improperly stored, and oil-stained areas on the ground surface. DEP issued an Order requiring Mitral to discontinue the release and to investigate pollution resulting from their disposal practices. In 1989, DEP issued an Order requiring the company to provide safe drinking water to impacted residences, and later  referred them to the Attorney General for failure to comply with the Orders.  Mitral ceased operations and filed for bankruptcy.  Subsequently, DEP removed approximately 100 drums of solvents and other wastes from the site and extended public water to the affected residences in 2006.  Between 2007 and 2009 EPA demolished the manufacturing building, treated the oil and TCE-contaminated soils and restored the property.

The Newhall Street Neighborhood is primarily residential, comprising an 18-block area in the southern part of Hamden, which includes two Town-owned parks and a former middle school. It had historically been wetlands that were filled with industrial waste and incinerated household trash from the late 1800s to the mid-1900s. In 2000, while planning expansion of the former Hamden Middle School, the presence of contaminated waste fill was discovered there. Subsequent environmental investigations of the neighborhood found the fill contained polynuclear aromatic hydrocarbons (PAHs), heavy metals, including lead and arsenic, petroleum, volatile organic compounds (VOCs), PCBs, and pesticides. EPA performed emergency excavation of soils with levels of lead that exceeded the immediate action trigger of 1,200 milligrams per kilogram at 13 residences in 2003.

 

A 2003 Consent Order was issued to Olin Corp., the Town of Hamden, South Central CT Regional Water Authority (RWA), and the State Board of Education (BOE). Olin and DEEP (on behalf of BOE) shared the $35M expense to to clean up the non-public properties, which included excavation and disposal of the top four feet of waste at ~220 privately-owned properties. In 2012 the Town cleaned up the two neighborhood parks, which included $4M of State Superfund monies. Caps to prevent the infiltration of water through contaminated fill were installed at both parks. In 2015 the RWA cleaned up the former middle school by removing the PCB-contaminated fill, injecting remedial agents to break down the VOCs, placing four feet of clean soil over the waste, and recording an environmental land use restriction to prevent excavation. Later, shallow pockets of fill were found on ~10 properties outside of the CO boundary area, which DEEP cleaned up in 2018.

 

The Town established the Newhall Local Design District to prevent future exposure to remaining deep waste fill, requiring property owners to notify the Town of any excavation deeper than four feet. DEEP and Olin established a long-Term Soil Management Fund to cover costs for proper disposal of any deep waste fill excavated under a Town-issued building permit.
 

A welding shop was thought to have contaminated a public water supply well because of its solid waste disposal practices.  DEP issued an Administrative Order, to the owners in 1983 requiring site investigation and remediation. They did not do the required work, so DEP conducted site investigation and determined that the site no longer constitutes an unacceptable threat to the environment.

In the early 1990s, residential wells were found to be contaminated with tetrachloroethylene (PCE). The source of this contamination was a dry cleaning operation that had previously operated at the Osborn Correctional Institute a half mile north of the neighborhood. In 1995, the State connected sixty-two residences to public water and monitored additional residential wells.  The State cleaned up multiple areas of PCE pollution on the prison grounds. The Department of Corrections continues to monitor and remediate this area under Order.

The South Pine Creek site is located in a residential area within one mile of Long Island Sound. Coal gasification waste was discovered in 1987 by the Town, which had reportedly been placed on the site as fill material during the 1940s.  The coal tar waste extended onto three private residential lots and a Town-owned tidal wetland conservation area. In 1998 the coal tar waste was removed. Some areas of fill were left in place because they were distinctly different than the coal tar waste and were identified beneath a layer of soil, which prevents human direct exposure.  The former Fairfield Municipal Landfill is located upgradient of the site and other types of fill have been identified in the area.

Starr Property, off of Simon Road, Enfield

The DEP excavated and properly disposed of coal tar contaminated soils and bulky wastes in 1996 and 1997.

In the late 1970s, a former dairy farm milking parlor had been used for automobile and snowmobile repairs. 1,1,1 Trichloroethane (TCA), a chlorinated solvent, was used to clean parts and dumped on the ground and into a floor drain.  A 1991 fire destroyed the repair shop, resulting in the additional spillage from one or two drums of TCA. In 1993, DEP discovered a number of area drinking water supply wells had been polluted by TCA and provided affected residences with potable water.  In 1994, DEP issued an Order to the owners requiring them to investigate and remediate the property and to provide an alternative source of potable water to affected residences and the owners appealed.  DEP extended public water to the area in 1999-2000 and connected thirty affected and at-risk residences. DEP performed an environmental investigation at the site and its vicinity and initiated remediation.  In 2000, the owners were held responsible for pollution at and emanating from the site and a lien was placed on the land to reimburse the State's costs.

The mixed residential, commercial, and industrial area is bordered by Saybrook Road (Route 154) and the Connecticut River. In the early 1980s, DEP became aware that several area drinking water wells were polluted with solvents, including trichloroethene (TCE), 1,1,1-trichloroethane (TCA), tetrachloroethene (PCE). DEP issued Orders to abate pollution to several entities at that time. Groundwater pollution persisted, despite remedial actions performed on some properties, prompting DEP to include the Tylerville site on the State Superfund Priority List. 1,4-Dioxane, a solvent stabilizer, was detected in water from several residential wells and methyl tert-butyl ether (MTBE), a former gasoline additive, had been found in five drinking water wells.

A 2013 Stipulated Judgment requires The Sibley Company to investigate and remediate pollution at its site. Mercury Fuel cleaned up pollution at its gas station under a 2012 Consent Order.  DEEP completed a regional groundwater investigation in Tylerville to determine whether there were other pollution sources in the area and extended public water to all the affected properties.

Yaworski Landfill (Canterbury Landfill), Packer Road , Canterbury

The Yaworski Landfill is a former private solid waste landfill located between Packer Road and the Quinebaug River, which had been active from the 1950s to 1995. A landfill gas collection and flare system installed in 1993 is no longer in operation. The landfill was capped. The Yaworskis also operated a waste lagoon to the west of the Landfill site from 1949 to 1973 (see EPA Yaworski Waste Lagoon NPL webpage).