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EPA and Delaware Enforce Clean Air Act Standards at Cherry Island Landfill

Release Date: 3/2/2004
Contact Information: Donna Heron, 215-814-5113 & and Melinda Carl, 302-739-4506

Donna Heron, 215-814-5113 & Melinda Carl, 302-739-4506

PHILADELPHIA – In coordinated legal actions, the U.S. Environmental Protection Agency and the Delaware Department of Natural Resources and Environmental Control (DNREC) have cited Clean Air Act violations at the Cherry Island Landfill, a landfill in Wilmington, Del. operated by the Delaware Solid Waste Authority (DSWA).

An EPA complaint issued to DSWA alleges violations of regulations designed to reduce air pollution from municipal solid waste landfills. EPA’s complaint proposes a $75,900 penalty for these alleged violations.

A separate DNREC compliance order cites violations of Delaware's solid waste and air pollution regulations and proposes DSWA take corrective actions within specific time frames to promptly comply with applicable federal and state air pollution control regulations. DNREC's notice of conciliation and penalty order assesses a $135,000 penalty.

“This case demonstrates the commitment of the EPA and the State of Delaware to enforcing the Clean Air Act,” said EPA Regional Administrator Donald S. Welsh. “Methane gas can present health and safety hazards and its presence in the atmosphere affects the earth’s temperature.”

“We consider these violations serious,” said DNREC Secretary John A. Hughes. “In some cases these violations have resulted in odors that have affected the quality of life in local communities. At the same time we recognize that the authority is making progress toward capturing fugitive emissions with improvements to its gas collection and transportation systems. The authority has been responsive and cooperative in trying to address these problems.”

Methane is a naturally-occurring, odorless gas. In the U.S., methane is primarily generated by decomposition of wastes in landfills, manure, domestic livestock, natural gas systems and coal mining. Hydrogen sulfide, another landfill gas, is odorous with a smell resembling rotten eggs.

The decomposition of solid waste at landfills produces harmful air emissions, including methane gas, which contributes to global climate change and may create fire and explosion hazards; volatile organic compounds, which contribute to smog; and other hazardous air pollutants. Under EPA regulations, large municipal solid waste landfills that were constructed or modified after May 1991 must have landfill gas collection and treatment systems. With these systems, methane gas from landfills may be captured, converted, and used as an energy source.

In November and December, 2003, EPA, accompanied by DNREC officials, inspected the Cherry Island Landfill, located at 12th Street and Hay Road in Wilmington. One of three DSWA-operated landfills in Delaware, this 240-acre facility is designed to hold 10.42 million tons of solid waste, including municipal and residential solid waste, construction and demolition debris, tires, household yard waste, and appliances.

EPA estimates that waste decomposition at the landfill annually produces more than 100 tons of methane gas, and more than 50 tons of non-methane organic compounds. Cereza Energy, Inc. has a lease agreement with DSWA to operate a collection system for landfill gas, which Cereza processes and sells to Conectiv’s Edgemoor plant for energy production. Cereza Energy, Inc. is responsible for the design, installation and operation of the gas collection system at Cherry Island Landfill.

On November 12 and 20, 2003, EPA, accompanied by DNREC officials, monitored landfill gas concentrations at sample wells and other locations throughout the landfill, documenting 32 points where surface concentrations of methane gas exceeded the Clean Air Act limit of 500 parts per million (ppm). At a followup visit on December 2, 2003, EPA and DNREC inspectors found that the landfill failed to take required corrective actions at three previously monitored locations, which still exceeded the 500 ppm methane threshold. Operational records of the landfill’s gas collection and treatment system also documented several unauthorized system outages in 2003 that exceeded one hour, in violation of Clean Air Act regulations.

Prior to the November and December inspections, DNREC issued citations to DSWA for six separate odorous emissions incidents during the period March 1 through October 27. DNREC's conciliation order notes that DSWA's solid waste permit requires it to “operate and maintain the gas extraction system, and landfill gas processing and distribution project to control odors.” In addition, during a May 2003 inspection by DNREC air quality staff, a number of violations were identified which are addressed in DNREC’s order.

Corrective actions for compliance listed in DNREC's conciliation order include improvements to the landfill's transmission lines, compressor capacity and soil cover. Monitoring and surveying issues are addressed as well as installation and implementation of odor neutralizers/masking agents.

DSWA has the right to a hearing to contest the alleged violations and proposed penalty in both the federal and state orders.

For more information about landfill gas, its regulation and re-use, visit EPA’s website at and .