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Fact Sheet 1

Fact Sheet #1 November 2010

Hillside, Illinois


The 55-acre former municipal solid waste landfill located at 4100 West Frontage Road, Hillside, Illinois, commonly known as the Congress Landfill or the Hillside Landfill is owned by Congress Development Company and has been operated by Allied Waste Transportation, Inc. since 2007. During the history of the landfill, odor complaints have been common. In 2005, there was a significant increase in the frequency and strength of odors impacting residents surrounding the landfill and a resulting increase in odor complaints to the Illinois Environmental Protection Agency. In 2006, landfill gas was found to be migrating offsite potentially causing hazardous conditions in nearby buildings. The Illinois EPA and the Illinois Attorney General’s Office took action at that time forcing the landfill to address problems that were immediately dangerous offsite, including requiring monitors in basements for the detection of landfill gas. Since 2006, there have been continuing odors, high landfill gas readings and other incidents including a leachate release in 2009, although actions taken by the landfill to address these issues have greatly reduced the strength and frequency of these issues.

Since the 2005 and 2006 incidents, the Illinois EPA, Attorney General’s Office and the landfill operators have been working to address the longer term issues associated with odors and landfill gas and leachate collection at the site. Oversight of landfill activities and regular meetings to discuss operations and ongoing work at the landfill have resulted in three previous settlement agreements that addressed specific work requirements and the current Final Consent Order between the State of Illinois and the Congress Defendants addressing the longer term problems and the eventual final capping and closure of the landfill. The Final Consent Order also requires the Congress Defendants to pay a civil penalty. This factsheet discusses the conditions of the Final Consent Order.

What does the Final Consent Order do?

On August 17, 2010, the Illinois Environmental Protection Agency (Illinois EPA), the Illinois Attorney General’s Office (AGO) and the Congress Defendants (Congress) entered a Final Consent Order in the Circuit Court of Cook County requiring that Congress take certain actions to address alleged violations of the Environmental Protection Act and Illinois’ environmental regulations at the Hillside Landfill. The Consent Order provides the framework and requirements for Congress to achieve and maintain compliance at the landfill with the Illinois Environmental Protection Act, the environmental regulations, and all of the terms and conditions of permits issued to the landfill.

The Consent Order also requires the payment of a civil penalty.

Who are the Congress Defendants?

Congress Development Co., John Sexton Sand & Gravel Corp., and Allied Waste Transportation, Inc. are called collectively, the “Congress Defendants”.

How much is the civil penalty that Congress must pay?

Congress is required to pay a civil penalty of $1,000,000. This money is paid into the State of Illinois’ Environmental Protection Trust Fund.

What activities have the landfill operators undertaken or completed prior to this Consent Order to mitigate odors and correct other problems at the landfill?

In January of 2007, the AGO entered a second preliminary injunction with the court. Since then many activities have been accomplished, including:

  • A slip liner system has been installed along the perimeter of the landfill;
  • Improvements to the landfill gas collection system;
  • Improvements to the leachate management system including leachate extraction wells;
  • Installation and operation of two enclosed flares;
  • Placement of over 266,000 cubic yards of protective soil cover over the 55 acre landfill footprint;
  • Development and implementation of a settlement monitoring program;
  • Installation of eight temperature probes;
  • Installation of nine pressure transducers to monitor pressure within the waste mass; and
  • Installation and operation of a leachate pretreatment plant that is designed to treat up to 125,000 gallons per day prior to discharge to MWRDGC;
  • Also, as a requirement of an Order entered by the Village of Hillside in March 2007, Congress installed 55 acres of an impermeable final cover system made up of geomembrane panels.

There has also been a significant reduction in both reported odor complaints and surface emissions exceedances.

What future activities are mandated by the Consent Order?

The Consent Order requires Congress to create a Landfill Compliance Plan which will be subject to review and approval by the Illinois EPA and AGO. The Landfill Compliance Plan will be kept at the landfill.

The Landfill Compliance Plan will outline the work that must take place at the landfill. Specific areas will be addressed by separate Work Plans. The Landfill Compliance Plan must address the following Work Plans:

  • Landfill Settlement
    • Settlement monitoring and remedial action,
    • Final cover replacement;
  • Landfill Gas and Air Quality Plan
    • Gas Collection and Control System,
    • Gas Collection Operating Standards,
    • Gas Migration and Monitoring,
    • Community Relations Plan with an Odor Complaint Protocol,
    • Odor Monitoring Plan;
  • Landfill Monitoring and Corrective Action Plan (LMCAP);
  • Leachate Plan;
  • Surface Water Plan;
  • Groundwater Plan; and
  • Systems Identification Plan.

The Consent Order also contains a Compliance Schedule that details the deadlines for specific objectives that must be met in regard to the Landfill Compliance Plan.

Until each Work Plan is approved under the Consent Order, the Work Plan requirements of the Second Supplemental Agreed Preliminary Injunction and Order from 2007 will remain in force.

What happens if the Congress Defendants fail to complete an activity or comply with requirements by the dates specified in the Consent Order?

Congress is required to notify the Illinois EPA and AGO of failure to comply with the Consent Order and will be subject to a penalty of $300.00 per violation per day until compliance with the Consent Order is achieved.

Ongoing communications with Congress and the reporting requirements described below will allow the Illinois EPA and AGO to determine quickly whether Congress is meeting the requirements of the Consent Order.

Now that the Consent Order has been signed, what are the next activities to happen at the landfill?

There will be an ongoing effort to reduce leachate and gas levels within the landfill. This will include continued maintenance and monitoring activities conducted on both the landfill gas collection and leachate management systems.

Two new leachate storage tanks and a leachate load out pad will be constructed. There will be continued filling and grading activities where settlement has occurred to prevent the ponding of precipitation and infiltration of precipitation into the landfill.

The AGO and Illinois EPA will continue to hold monthly meetings with Congress to review ongoing operations and work at the landfill pursuant to the Consent Order.

Monthly reports will be submitted to the Illinois EPA and AGO to provide updates on parameters established in the Consent Order and twice yearly reports assessing the condition of the landfill will be submitted to the Illinois EPA and AGO.

What is leachate and how does it affect the gas collection system?

Leachate is the liquid in the landfill that accumulates when water, usually rainwater, travels through and mixes with the waste. Leachate can become contaminated with toxic substances depending on the nature of the waste present within the landfill.

When leachate levels are too high, as at the Congress Landfill, leachate will fill the gas extraction wells causing them to clog and be unusable for gas extraction.

Leachate levels must be lowered to allow proper function of the landfill gas extraction wells.

Does the landfill still accept waste?

The landfill stopped accepting garbage on January, 2008. However, due to decomposition of waste in the landfill there has been substantial subsidence or settling on portions of the landfill. To correct the subsidence and prepare for a final cap, the landfill is allowed to bring soil on site as fill. Some of the soil may be considered waste by statute if it comes from construction sites or other similar sources.

How can I find out more information about the landfill as work progresses?

As part of the Landfill Compliance Plan, Congress must develop a Community Relations Plan including a protocol establishing a process for the public to contact the landfill to submit odor complaints. The Community Relations Plan will provide a framework for Congress to update the surrounding community about work at the landfill. The Illinois EPA will be reviewing the Community Relations Plan and will be monitoring the outreach work and the number of odor complaints received by the landfill.

As significant milestones are reached at the landfill, the Illinois EPA will be conducting additional outreach. If you would like to be placed on the Illinois EPA’s mailing list for the landfill, please contact the Illinois EPA at the contact listed below.

Information about the Consent Order, monthly and semi-annual reporting and the Work Plans may be obtained from the Illinois EPA at the contact listed below.

For more information from Illinois EPA, contact:

Brad Frost

Office of Community Relations

Illinois EPA

1021 North Grand Avenue, East

P.O. Box 19506

Springfield, Illinois 62794-9506

(217) 782-7027

(217) 524-5023 fax

For updates on the work at the landfill, Congress maintains a website at: