FAQ

Q - What are manufactured gas plants (MGPs)?

A - In the 1850s, a new energy source came to Illinois. Coal was used to manufacture “town gas” in a community. The gas was first used to light homes, businesses and streets and later for heating and cooking. The town gas era ended when interstate pipelines brought natural gas to our state. The Skokie former MPG operated from about 1910 until the mid-1950s.

Q - How was the gas produced?

A - Heating coal, coke or oil was heated in a closed structure to generate gas. After the gas was cleaned of impurities, it was stored in large tanks known as gas holders before it was distributed throughout a community.

Q - What are the gas manufacturing byproducts and residues?

A - Tar was the primary byproduct of the gas manufacturing process and was often sold to other manufacturers. Tar is a component of several products we use today, including dyes, some shampoos, driveway sealants, and asphalt roofing and paving materials. Residual ashes, cinders and tar may be found on the ground surface or below ground in storage wells and bases of the gas holders.

Q - Are gas manufacturing residues health and environmental problems?

A - The primary compounds of interest in tar are polynuclear aromatic hydrocarbons, or PAHs, and benzene. PAHs are widespread in the environment because they are products of combustion, such as running a gasoline engine or burning coal or wood. Likewise, benzene is widespread in our daily environment from such sources as gasoline stations, auto exhaust, household cleaning products, and cigarette smoke. At the Skokie site, the potential for exposure to any of these compounds is unlikely for several reasons, including the fact that the site has been closed for many years, no one is occupying the property, access is limited, most hydrocarbons are likely buried beneath the surface and the groundwater beneath the site is not in use. A risk analysis prepared by nationally respected outside consultants demonstrates that there are no health risks associated with the proposed investigatory work at the site.

Q - How will the site investigation be conducted?

A - Nicor Gas has retained Burns & McDonnell, an engineering firm experienced with gas manufacturing sites, to perform the environmental investigation, which consists of:

• Clearing brush and trees less than 8 inch diameter, leaving all vegetation within 5 feet of the perimeter fences.
• Using a magnetometer and ground-penetrating radar to look for potential buried drums.
• Collecting several hundred soil samples with soil probes and soil borings.
• Excavating 44 test pits in areas where old maps indicate structures may still exist below ground.
• Collecting samples from four groundwater monitoring wells.
• Shipping samples to an independent laboratory for chemical analysis.

Work at the site is expected to take up to five months.

Q - How will the study affect the surrounding area?

A - In the early weeks of the project, workers and equipment will access the property from the Skokie Sports Park parking lot. Nicor Gas and Commonwealth Edison (the Utilities) plan to construct a new entrance off Oakton east of the parking lot once they have obtained a permit to do so from the Cook County Highway Department.

Workers will be on site between 6:30am and 5:30 pm on week days. People are unlikely to view the work because of the vegetation surrounding the site perimeter.

Tar can generate odors similar to roofing tar or moth balls so people in the vicinity may notice an occasional odor if tars are encountered during the subsurface investigation. All work is carried out under a health and safety plan designed to protect the workers and minimize off-site impacts. Air monitors will be employed when investigatory work is occurring. They act much like smoke detectors do to alert workers to take steps to reduce vapors in the air before they reach unacceptable levels.

Q - What are the next steps in the site investigation?

A - Using the information collected during the on-site work and the laboratory results, the engineering firm will prepare a report for the Utilities as well as for the Metropolitan Water Reclamation District of Greater Chicago (MWRD), the property owner. The report will guide decisions on the need for further investigation and/or cleanup (remediation).

Q - Is there any litigation pending concerning this site?
A - In 2002, the MWRD filed a lawsuit against the Utilities in federal court.  MWRD v. Nicor, et. al., No. 02 C 1930 (Judge Nordberg; Magistrate Judge Schenkier). Shortly after the lawsuit was filed, the parties began negotiations concerning an investigation of the Skokie site. With court approval, the parties have agreed to suspend further litigation activities while the investigation is conducted. The Utilities are conducting this environmental investigation under a permit from the MWRD, in cooperation and coordination with the Village of Skokie and the Skokie Park District.

Q - Where can I get more information about the environmental study?

A - This website will continue to include information on the site, the type of work planned, relevant pictures and figures, public notices and additional resources for the duration of the project.

The Skokie Public Library, 5215 Oakton Street, has a collection of documents about the project, including a copy of the Site Investigation Work Plan, Community Relations Plan and other resources.

You can also contact 1-888-833-8918 or email us at comments@skokiesite.com if you have any questions or concerns.