New Jersey Zinc/Mobil Chemical

Fact Sheet #12
July 2009

Bureau County, DePue, Illinois

Background

The former New Jersey Zinc/Mobil Chemical Superfund site is located in the Village of DePue in Bureau County and consists of approximately 950 acres. The former zinc smelter plant began in the early 1900’s with operations including zinc smelting, and included sulfuric acid production, lithopone paint pigment production and zinc dust production. A diammonium phosphate fertilizer plant began operations in the 1960s.

Many of the plant operations took place before most environmental regulations; therefore, a potential existed for contaminants to be released into the air, water and land. Preliminary on-site and off-site sampling of surface water, soil, and sediments by the Illinois EPA indicated elevated levels of various metals. Due to the elevated levels, a notice was sent out the all potential responsible parties (PRPs) identifying actions that had to be taken at the site, as incorporated the 1995 Consent Order between the PRP’s, known as the DePue Group, and the Illinois EPA. These actions included an investigation of the extent and types of contamination associated with the site and a study of appropriate remedial measures.

Want to learn more?

HOLD THE DATE: Wednesday, August 12, 2009

The Illinois EPA will host two Public Availability Sessions at the VFW Hall in DePue on Wednesday August 12th. The sessions will be held from 3:00 pm to 5:00 pm and from 6:30 pm to 8:30 pm. Staff from Illinois EPA, Illinois Department of Public Health, Illinois Department of Natural Resources and the DePue Group will be available to discuss the results of the DePue Lake investigation and update the community about progress on the other Operable Units (OU’s) associated with the site.

Is the Lake Remedial Investigation complete?

Yes. The DePue Lake Remedial Investigation (RI) was finalized in July 2009. Consultants for the DePue Group have been working closely with the Illinois EPA to insure that the RI would be completed per an approved work plan. Complete copies of the Lake RI Report and all maps and data sets have been placed in the public repository at the DePue Public Library.

What can be done to clean up site-related contamination of DePue Lake?

The Feasibility Study (FS) is the next step in the investigation and eventual clean-up process. The Illinois EPA expects to have the Feasibility Study Report by early 2011. A Proposed Plan will be developed by the Illinois EPA and a public comment period and public hearing will be held to gather input from citizens.

Why has it taken so long for the responsible parties to focus on the clean-up of DePue Lake?

The initiation of the DePue Lake RI was delayed until the South Ditch action could be completed. The South Ditch was receiving and transporting contaminated flows from ground and surface water. The Remedial Investigation of the Lake could not be initiated until the Interim Water Treatment Plant was operational and the impacted sediment was removed from the ditch.

Describe the types of contamination that have been found in the DePue Lake.

Results of the Remedial Investigation indicate that concentrations of metals (zinc, cadmium, copper, lead etc.) are elevated. The highest concentrations of these metals were located near the South Ditch discharge area and south of Division Street.

What are the most likely exposure pathways to potential contamination in DePue Lake?

The most likely human exposure pathway with DePue Lake is incidental ingestion of the turbid water, sediment and soil through recreational activities.

Are the fish in DePue Lake safe to eat?

The Illinois Department of Natural Resources (IDNR) has issued an advisory to limit consumption of catfish and carp to 1 meal per month of any size, 6 meals / year of fish less than 24 inches and not to eat fish greater than 24 inches caught in DePue Lake. In addition there is an advisory to limit largemouth bass to 1 meal / week, Channel Catfish to 1 meal / week less than 12 inches, 1 meal / month between 12 and 18 inches, 6 meals / year 16 to 18 inches and not to eat Channel Catfish greater than 18 inches. Carp, all sizes, should be limited to 1 meal / month in the Peoria Pool. Please see the 2009 Illinois Fishing Information booklet from IDNR. (The advisories are for PCBs and Chloradane; the New Jersey Zinc/Mobil Chemical site is not believed to be a significant contributor of these contaminants.) The advice in this table has been developed to protect infants, children and women of child bearing age. The advice may be over protective for women beyond child bearing age and adult men.

What can I do to minimize my exposure to potential contaminants in and around DePue Lake?

After coming in contact with Lake water, be sure to wash your hands before you eat or drink anything. If you fish, boat, wade, hunt or in any other way use DePue Lake, wash any mud from your cloths, skin, boat, oars, fishing rods, lures, drain boat bilge water etc. before you leave the lake area.

DePue Lake Investigation

The DePue Lake Remedial Investigation was directed toward assessing not only the lake but also flood plain soils below 450 ft. mean sea level (MSL). The 450 ft MSL was selected to mirror the normal annual flood elevation of DePue Lake. To accomplish this task the lake was divided into segments using a grid; flood plain soils (above flat pool but below 450 ft MSL) were assessed using sampling locations spaced at either 250 ft or 500 ft intervals determined by the likely past involvement with site activity or discharges. At most sampling locations multiple samples were collected at pre-determined depths.

Sampling Summary
Sample TypeDePue LakeGoose Lake**Total Samples Analyzed
Total3971101108
NC* – Not Collected Goose Lake** – Near Lacon was used as a comparison to DePue Lake
Water Samples by Type
Shoreline Seeps10NC*10
Potential Under Water Seeps6NC*6
Lake Surface Water10 twice2 twice24
Sediment Samples by Type
Chemistry Cores (Deep)203214
Triad16562
Geochronology32203
Descrete Cores (Shallow)392120
Supplemental Focused Wading5NC*7
Flood Plain Soils8310183
Biotic Samples by Type
Fish Samples7525100
Aquatic Insects8412
Emergent Insects161026
Flood Plain Vegetation402060
Frogs201030
Mice201030
Benthic Organisms16521

For more information, you may contact:

Jay A. Timm
Community Relations Coord.
Office of Community Relations
Illinois EPA
(217) 557-4972
Rich Lange
Project Manager
Illinois EPA
(815) 447-2125