Gude Landfill - Division of Solid Waste Services

Thursday, November 26, 2009: Thanksgiving Day - No County-provided recycling or trash collections on November 26; Thursday and Friday collections that week shift by one day. Transfer Station closes at 5 p.m. on November 25; closed November 26.

Effective September 21, 2009, our recycling program expanded to accept additional blue bin and mixed paper items!

Landfill Operations: Gude

Location:

Gude Landfill Operating History

The Gude Landfill is the oldest formal landfill in the County and is located at 600 East Gude Drive, Rockville, Maryland 20850. The landfill was primarily used for the disposal of County municipal solid waste from 1965 to 1982. The landfill received approximately 4.8 million tons of municipal waste from 1965 until the site was closed in 1982. The Gude Landfill has a waste disposal footprint of approximately 100 acres. The depth of waste at the site varies from about 55 feet to 100 feet and the waste limits are delineated near the property boundary. There is very little buffer area.

An incinerator operated at the site from 1965 to 1975, giving the name Incinerator Lane to the entrance off Southlawn Lane. The incinerator was demolished in the early 1980s. Although it predated all modern landfill design regulations, the Gude Landfill was operated using daily cover soil to cover waste and reduce vectors and odors from the site. The final layer of waste is covered with two feet of soil, and the entire site is well vegetated with trees, brush and grasses.

Prior to the Gude Landfill, a region referred to as the Beantown Dump along the opposite side of Gude Drive was used by many for waste disposal.

Landfill Gas Management System

The Gude Landfill currently generates approximately 800 to 1,000 standard cubic feet per minute (scfm) of landfill gas, which is combusted at the existing enclosed ground flares. The gas consists of relatively equal percentages of methane and carbon dioxide that is generated naturally from anaerobic waste decomposition.

Landfill gas is collected through a network of pipes in the landfill that are connected to a blower system that draws the gas from the fill area. We recently installed 32 additional gas extraction wells to complement the 40 to 50 extraction wells were already in place. The new wells were installed to mitigate offsite migration of landfill gas along the northwestern side of the property.

We have a landfill leachate pretreatment plant at the Oaks Landfill, about 8 miles away, which accepts landfill gas condensate generated at the Gude Landfill.

Former Gas to Energy Recovery System

To address concerns about the potential for landfill gas migration, a lease for the development of a landfill gas collection and energy recovery system at the Gude Landfill was executed in 1983 and an operating system was installed in 1985. The gas was collected with an extensive system of 40 to 50 wells and pipes. It was directed to an on-site power plant consisting of two 150-horsepower motor-driven compressors that delivered gas to two 2,000 horsepower internal combustion engines. Each engine drove a 1.5 MW generator, and the system generated about 2.7 MW of electrical power, enough to meet the needs of about 2,700 homes. The former operator of the power plant and gas recovery system was Ogden Power Pacific, Inc. and later became Covanta Power Pacific, Inc.

Until the spring of 2006, the landfill gas was collected by Covanta Power Pacific, Inc. (CPPI). The former power plant and related infrastructure was decommissioned and the existing building was rehabilitated for potential future storage use by us.

New Gas to Energy Facility (Future per MDE & County Permitting)

The new Landfill Gas to Energy (LFGE) Facility will take the landfill gas (35-40% methane) that previously went to the enclosed ground flares and beneficially use the methane content in one engine/electrical generator system (containerized Jenbacher JGS 316 engine) to generate electricity. The new LFGE Facility will be smaller and more efficient than the former landfill gas facility that operated at the Gude Landfill from 1985 to 2006. It will be located behind the former power plant building, adjacent to the landfill gas enclosed ground flares’ noise wall at the Gude Landfill. The LFGE Facility will be surrounded with a chain link fence with locking gates. The former power plant building structure and the landfill gas enclosed flares’ noise wall will help mitigate noise produced by the engine/electrical generator system equipment. This project will use Capital Improvement Program funding.

The new LFGE Facility will also incorporate a remote computer-based system to detect if the facility shuts down. It will have personnel that are on-call 24-hours a day, 7-days a week for system maintenance and repair.

The existing landfill gas ground stack flare(s) will operate concurrently with the new LFGE facility to mitigate the potential for landfill gas migration.

Landfill Environmental Monitoring

The Montgomery County Department of Environmental Protection (DEP) semi-annually monitors the ground water and surface water around the perimeter of the landfill site and reports the results to MDE and us. There is some contamination at the site; however, the contamination is sufficiently low such that no formal remediation is required, aside from maintenance of the soil cap to maintain stormwater management and the correction of leachate seeps to the extent feasible.

DEP also monitors the seven gas migration wells that were installed along the northwestern slope for the presence of landfill gas on a routine basis and reports the results to us. The migration wells consist of three tiered probes located at varying depths (shallow, intermediate, and deep that range from 5-feet to 38-feet in depth) in the subsurface. Other ongoing activities at the site include maintenance of monitoring well access roads and the landfill gas management system and the ground stack flares, repairs to storm water management structures, and correction of ponding and eroded areas.