Remediation Activities at the Wells G & H Superfund Site

These photographs were taken by Professor Scott Bair during a 2000 field trip to see the contaminant remediation systems. The site visits were arranged through U.S. EPA Region I. Jonathan Harr, Jan Schlichtmann, John Guswa, Gretchen Latowsky, and Chuck Myette were also part of the entourage that heard employees of ReTec, W.R. Grace, Harvard Project Services, and U.S. EPA explain the function and operation of the remediation systems at four of the eight contaminated properties within the Superfund Site. A detailed explanation of the remediation systems in the Wells G & H Superfund Site is presented in (Bair and Metheny 2002 ).

Beatrice Foods, Inc. - Wildwood Conservation Trust

The remediation systems at the 15-acre woodland, which is now known (ironically) as Wildwood Conservation Trust, contains 5 deep wells, 24 air sparging wells, and 1500 linear feet of perforated soil-vapor extraction pipe buried in a 3-foot thick gravel bed covering 3 acres adjacent to the river. In its first three years of operation it recovered 2260 lbs of VOCs.

Debris, drum carcasses, and contaminated soil removed from property
3 acre gravel bed contains air sparging wells and soil vapor extraction pipe
Three acre gravel bed adjacent to floodplain
Vault with air sparging lines
Vault into soil vapor system

One of five extraction wells
Treatment building at Beatrice - 2000 sq ft
Groundwater from the 5 extraction wells goes through (yellow tanks) sand filters
After filtering groundwater goes through air stripper
Organics from SVE system combusted in catalytic oxidation unit

W.R. Grace & Company - Cryovac Property

The remediation system at W.R. Grace contains 22 pump-and-treat wells that together yield 5-8 gpm and treatment with peroxide, UV oxidation, and carbon filtration. The system began operation in 1992. In the first nine years of operation, 31 million gallons of groundwater were extracted from the underlying glacial sediments and bedrock, and 66 lbs of VOCs were recovered from the contaminated water.

Extraction wells in vaults on southside of WRG buildings
Open vault showing one of 22 extraction wells
Treatment building in back of WRG property
Controls for pneumatic pumps in extraction wells
Pressure tank for pneumatic wells

Peroxide added to influent (contaminated) water
Overview of WRG treatment system
Two 5000 watt UV lamps in series destroy TCE and PCE
Renovated water discharged to Snyder Creek


The remediation system at UniFirst became operational in 1992. It uses a 190-foot deep bedrock well to capture contaminated groundwater that is treated with peroxide, UV oxidation, and carbon filtration. In its first nine years of operation, it recovered 1731 lbs of VOCs from 193 million gallons of contaminated water.

Bedrock extraction well UC-22 produces 45 gpm
Peroxide added after filtering
Jonathan Harr, Jan Schlichtmann, and Chuck Myette
Six 10,000 watt UV lamps used to destroy PCE and TCE
Carbon polishing units

New England Plastics

This simple pump-and-treat system has a small footprint in the parking lot behind the former NEP building. The system has six air sparging wells and seven soil-vapor extraction wells. In 15 months operation it recovered 80 lbs of VOCs.

Small air sparging and SVE system at NEP
Fresh asphalt keeps contaminated air trapped in soil
Air sparging pipe (small) and SVE pipe (large)
Manifolds controlling seven air sparging wells
Vapor and water from six SVE wells go into separate carbon units

Hemingway Transport Company - Olympia Nominee Trust

While the remediation systems at the other four contaminated properties within the Wells G & H Superfund Site were operational beginning in the mid-1990s, contamination at the former Hemingway Transport property was still being characterized. As of 2006, no remediation system was in place. The characterization studies did find additional locations of severe groundwater contamination on the property.

Other Contaminated Properties in the Superfund Site

Several other properties with groundwater contamination are present within the 330 acre area comprising the Wells G & H Superfund Site. Collectively these are known as the 21E Properties and include Murphy Waste Oil, Aberjona Autoparts, and Whitney Barrel. All three of these properties occur on the north side of Salem Street west of the Aberjona River within the buried valley. Characterization studies are proceeding on these properties. Remediation designs and construction are not yet known.