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Rockford Power Machinery) Nylint Corporation, and Rohrbacher Manufacturing were also primary
facilities in the area, but are no longer in operation (CDM, 2000 RI 1-7, 3-55).
The geology at Area 9/10 is unconsolidated sand and gravel to a depth of at least 101 feet bgs, as
determined by SB9/10-201. No clay or silt units were encountered (with the exception of some fill
material within eight feet of the ground surface) in the borings conducted by CDM for the Operable Unit
Three investigation. Information from boring logs for two borings conducted near the intersection of
Ninth and Harrison Avenue indicate that the unconsolidated sand and gravel in Area 9/10 continues to
approximately 235 feet bgs, where bedrock is encountered. One of the boring logs from Illinois State
Geological Survey well records identifies a till unit from 120 to 130 feet bgs. Borehole drilling just west
of Area 9/10 at the intersection of Twenty-third Avenue and Fourth Street indicated that the
unconsolidated sediments are at least 169 feet thick, with a 12-foot-thick clay unit from 132 to 144 feet
bgs. The water table at Area 9/10 is generally encountered between 30 and 35 feet bgs (CDM, 2000
RI 3-55, 57).
Investigation results, summarized below, indicate that significant sources of VOC contamination exist
within Area 9/10. Four primary potential source locations within Area 9/10 were investigated and are
discussed below.
Sundstrand Plant #1
Available information regarding Sundstrand Plant #1 (Illinois EPA 104e Requests; Harding Lawson
Associates 1992) documents the existence of three major potential source areas at the facility: (1) the
Outdoor Storage Area; (2) the loading dock; and (3) the Waste Recycling Area. Additional sources of
contamination include underground storage tanks (USTs) located throughout the facility and other
historical solid waste management units (SWMUs). Some of the other SWMUs contained within the
facility include a wastewater treatment plant, an old plating area, a sodium dichromate line, an old
dichromate line and an old drum wash area. The Outdoor Storage Area, formerly located at the
southwest corner of Ninth Street and Twenty-third Avenue, was used to store VOCs. Soils located
below this area had elevated concentrations of VOCs. Additionally, an underground storage tank
(UST) adjacent to the Outdoor Storage Area was used to store VOCs.
During its history, Plant 1 has contained numerous USTs related to different activities at the facility.
These USTs ranged in capacity from 500 gallons to 10,000 gallons, and numbered up to 40 USTs at
any one time. Records indicate that many old USTs have been removed or abandoned in place for a
variety of reasons, including leaking tanks. Construction of some of the USTs and their associated
piping systems include many that were made of steel. The loading dock at Plant #1 has contained
approximately 14 USTs at various times between 1962 and 1987. USTs at Plant 1 contained a variety
of materials including: chlorinated solvents, stoddard solvent; cutting oils; fuel oils; lapping oil; 1318 oil;
rust oil; DTE 25 oil; mineral spirits (7024 or Naphthol spirits); petroleum naphtha; gasoline; and jet fuel
(JP4, JP5, and JP8). Some of the tanks within the facility were used to contain waste materials such as:
used JP4; used 7024; waste oil; and solvents (PCE, TCE, 1,1,1-TCA, Stoddard). The Waste
Recycling Area is the third potential source at Sundstrand’s Plant #1. The Waste Recycling Area is
located inside the facility, and is up gradient of the west end of the Nylint building (CDM, 2000 RI 3-
75,76).
