The Site is located on the south side of the 2000 block of Berkley Street in Rockford, Illinois. The meridian coordinates of the Site are latitude 42°16’19.40” North and longitude 89°07’14.77” West. The Site is bordered to the north by Berkley Street, to the east by Stewart Avenue, to the south by Preston Street, and to the west by Webster Avenue. The Site consists of two residential properties and other parcels that comprise 2.5 acres of land in a mixed residential/industrial area (Figure 1). The two residences are occupied and at one of the residences, a small child of approximately 5 years old visits the house daily. Both residences obtain water from a public water supply line. The other parcels that comprise the Site consist of empty lots with grass and trees. Industrial facilities are located immediately south of Preston Street. The Rock River is located approximately 1.5 miles to the east and Leavings Lake is located approximately 0.8 miles to the southwest.
In 1999, while excavating a water line, the City of Rockford encountered soil stained blue along Berkley Street. Initial sampling of the soil indicated a pH of 2.93 standard units (SU). In May 2000, the Illinois Environmental Protection Agency (IEPA) collected 12 soil boring samples from a vacant property northeast of the stained soil area. The soil borings did not contain unusually colored soil, and the sample results did not indicate elevated levels of contamination.
In June 2010, residents contacted IEPA with complaints that a blue material was infiltrating into their basements from foundational cracks and a sump in two homes along Berkley Street. IEPA collected three surface soil samples and a scraping of the material inside one of the basements. The samples were analyzed for volatile organic compounds (VOC), metals, and cyanide. No VOCs were detected in the samples. Arsenic and cadmium were detected at concentrations exceeding the Agency for Toxic Substances and Disease Registry (ATSDR) Environmental Media Evaluation Guide for Children (EMEG) health-based screening values. Cyanide was not detected in any of the samples at concentrations exceeding the health-based screening values. The Illinois Department of Public Health (IDPH) reviewed the surface soil data and determined that surface soil did not pose a health hazard. However, a soil sample from one of the residences had a low pH, and IDPH warned the resident about dermal contact with the acidic substance. The material from the basement was determined to pose a health hazard to a young child which does not live at the residence but visits the home daily.
In September 2010, IEPA obtained additional subsurface soil data for six samples from 14 soil borings. The soil samples were analyzed for semivolatile organic compounds (SVOC), metals, and cyanide. In eight of the borings, a defined layer of blue-stained soil was observed from 2 to 8 feet below ground surface (bgs), and samples from five borings had acidic pH values (2.1 to 3.9 SUs). The samples contained seven SVOCs at concentrations exceeding the ATSDR EMEG values. In addition, arsenic, cadmium, and cyanide were detected at concentrations exceeding the ATSDR EMEG values.
Based on personal communication between U.S. EPA and ATSDR, ATSDR indicated that the blue material appears to be Prussian Blue (iron cyanide). Although the source of the contamination under the homes is unknown, several facilities in the area are potential sources, including a former tractor manufacturer that operated coke ovens and a cyanide heat treating process to harden metal.
On April 26, 2011, U.S. EPA conducted a site assessment. Twelve soil borings were advanced. From the twelve soil borings, six soil samples and one groundwater sample were collected. In addition, two surface soil samples that were not from the soil borings were collected. Sample results indicated elevated levels of arsenic, benzo(a)pyrene, and cyanide above the ATSDR screening levels. Specifically, arsenic levels were as high as 25 milligrams per kilograms (mg/kg), benzo(a)pyrene levels were as high as 12 mg/kg, and cyanide levels were as high as 3,500 mg/kg. pH levels in soil were as low as 3 standard units.
The removal action will address the contaminated water seeping into basements by sealing cracks and waterproofing the residential basements. A water proof membrane will be installed on the walls of the basement and sumps with pumps and a french drain will be installed on the inside wall. The water collected will be pumped to the back yard and infiltrate beneath the surface in two dry wells installed 2 feet below ground surface. This will eliminate the surface contact threat from the material leaching in the basement.
USEPA will work with the City of Rockford to place some institutional controls on the additional lots on the block that have the impacted material on the property.
