After exploring various options, the Town Council of Groton, CT, developed a residential waste transfer facility that ably serves its residents.

By Nancy M. Oram and Gary Schneider

Prior to the promulgation of EPA Subtitle D landfill regulations, the coastal town of Groton, CT, used three landfills for the disposal of waste generated by its 40,000 residents and commercial establishments—one MSW landfill and two for bulky waste items. Realizing it would not comply with the 1993 deadlines established by these new rules, the town entered into a long-term agreement with the Southeastern Connecticut Regional Resource Recovery Authority (SCRRRA) for the disposal of its MSW at SCRRRA's nearby waste-to-energy facility. This facility is 12 miles from the town's transfer station and offers a reasonable tipping fee, representing the lowest cost alternative for offsite disposal.

Groton closed its MSW landfill and focused on reaching capacity and closing the adjacent bulky-waste landfill, which occurred in 1997. That left the town with one bulky-waste landfill for the disposal of wastes not accepted at the SCRRRA facility. Because the state wanted to close all unlined landfills, the town signed a consent order with the Connecticut Department of Environmental Protection (CTDEP) to close its remaining landfill and come up with an alternative means of handling its difficult-to-manage (DTM) wastes, which include bulky waste, oversized MSW, construction-and-demolition debris, appliances, propane tanks, tires, scrap metal, brush and storm debris, batteries, and waste oil.

A study was done to define the waste items of concern, determine current and future waste quantities, and evaluate long-term options. All residential MSW was collected curbside throughout the town, so the study focused on materials that could not be or were not being collected curbside and/or were not accepted at the waste-to-energy facility. Six options were developed:

• No action: This option consisted of the town no longer providing a means for its residents to dispose of their DTM wastes.
• Residential-only transfer station: This option would provide a disposal location for residential DTM wastes only.
• Truc- haul transfer station for all town waste: This facility would handle both residential and commercial DTM waste generated within the town.
• Regional truc- haul transfer station: This facility would be similar to the prior option but would accept DTM waste from the region surrounding the Groton area.
• Regional rail-haul transfer station: This facility would be similar to the prior option, but DTM waste would be loaded into railcars and hauled out of town.
• New landfill: This would entail construction of a new landfill within the town, designed to handle the residential and commercial DTM wastes for 20 years.

Since the town wanted to continue providing DTM waste-disposal service for its residents, the no-action alternative was eliminated. A brief siting study was then done by comparing available land with the siting requirements for each type of facility. This analysis determined that developing a new landfill was not feasible due to lack of suitable land within the town. It also determined that no town-owned parcels were available for the larger amount of land needed to develop regional facilities or a facility to handle both residential and commercial DTM waste generated in the town. While purchase of a private parcel was considered, land costs in southeastern Connecticut precluded the feasibility of these options. The Groton Town Council ultimately authorized development of a residential DTM waste transfer station at its existing residential drop-off facility, even though this was not one of the lower-cost options.

The Site

The approximately 6-acre site of the existing facility was chosen to minimize costs and expedite implementation. This site was advantageous because it was already accepted by the residents, remote from the nearest neighbors, and owned by the town. The site included an existing equipment garage that was worth salvaging and several other small structures that were demolished prior to construction.

The following site constraints had to be considered:

• Location and ground elevation at the existing equipment garage
• Property lines and required setbacks
• The adjacent landfill, landfill gas flare, and SCRRRA recycling facility
• Location and elevation of existing entrance and exit access roads
• Buffers to Flanders Road required by the town planning commission
• Areas required for stormwater control and onsite sewage disposal

Habits of the residential users of the old drop-off facility were observed to optimize the new facility layout. Noted concerns included:

• Insufficient space for residents backing up trailers
• Unloading delays
• Insufficient number of dumping locations

Additionally, residents bringing woodwaste, brush, leaves, and appliances typically did not have other materials for disposal.

The town wanted to add a building with an office from which the facility manager could observe site operations, an employee lunchroom, restrooms for the employees and the public, and a drive-out basement for storage of consumer electronics and fluorescent bulbs.

Also important was ensuring that construction could be accomplished while the facility remained open for residents' use. Mike Picard, CDM associate, explains: "We needed to plan the site layout to allow uninterrupted use of the site as a residential drop-off facility while construction was taking place."

Based on these considerations, the site layout was divided into two main areas: one where materials were generally stockpiled for later processing or recycling, and one that included a retaining wall for grade separation to allow residents to directly deposit waste into containers. Construction was staged, allowing half the site to be used as a temporary drop-off facility while the retaining wall was being built, and switching operations to the retaining wall area while the stockpile area was finished.

Residents dropping off woodwaste, brush, and leaves are kept separate from other users in the new transfer station layout. These wastes can be deposited by parallel parking to the stockpile area (with three lanes of traffic available to pass those dumping), limiting the amount of backing required. Residents dumping bulky waste items or construction-and-demolition debris can bypass the stockpile area, driving directly to the retaining wall. A total of 14 dumping spaces are provided at the retaining wall, allowing quicker access to this area.

As residents enter the new facility, they drive up an access road with two curves (designed to reduce speeds) and approach the attendant's shelter. The attendant directs the residents to the stockpile area or the drop-off area at the retaining wall depending on the type of waste to be disposed of. The stockpile area has a road encircling it, allowing the drop-off of woodwaste, appliances, leaves, brush and yard debris, propane tanks, and tires. Residents can gain access to the give-and-take shed and drop off batteries, waste oil, and antifreeze in a three-sided shed along this road encircling the stockpile area. Residents disposing of scrap metal, oversized MSW, and construction-and-demolition debris bypass the stockpile area and deposit their items over the retaining wall.

To accommodate the tub grinder and trucks hauling rolloffs and trailers, a separate access road was constructed at the residential entrance that goes straight into the site, allowing vehicles with a large turning radius easier access. These vehicles typically use the site on days that the transfer station is closed to residents. A gate between the building and the grassed area where the septic system is located directs residential vehicles to the left around the access road leading to the attendant's shelter rather than directly into the site.

The Materials

During design of the transfer station, the town inventoried the various types of waste that were being delivered to the existing drop-off station and landfill. These wastes were categorized as materials that could be reused within the community (such as woodwaste and yardwaste), materials that could be recycled (such as waste oil and scrap metal), materials that needed special handling (such as tires), and all other materials that would require disposal.

The new facility was designed to accept the materials listed below. The town would also establish a small give-and-take center where residents could leave reusable items for others to take. The handling method for each of the materials currently accepted at the DTM waste transfer facility is discussed below.

Brush and yardwaste are accepted in a lay-down area and stockpiled. Once a sufficient quantity is collected (enough to keep the tub grinder busy for at least two days), a tub grinder that is owned and operated by SCRRRA is brought to the site and the woodwaste is processed. The material is ground twice, and the resulting mulch is made available to the town departments and residents.

Leaves and other compostable materials are collected at the facility and stockpiled as well. Once a week (or more often if required), the stockpiled leaves are brought to the town's leaf composting facility by town staff. Screened compost material is brought back to the site and made available to town residents at no cost.

Pallets are collected separately in an open-air stockpile area and reused by the town and its residents.

Empty propane tanks are stored in a remote area of the transfer station. Once a wee,k the town removes the valves (facility personnel have been trained in this procedure), recycling the empty bottle with the general scrap metal and recycling the brass valves separately.

Appliances are deposited by residents directly on a paved pad. Once a month, a specialized firm is contracted by the town to remove any Freon. Once the appliances are certified to be Freon-free, the town removes all capacitors and they are loaded into a rolloff container for delivery to a local scrap metal recycling facility.

Tires are loaded into a 53-foot box trailer and delivered to a tire-to-energy facility.

Consumer electronics and fluorescent bulbs are deposited in 1-cubic-yard gaylords, which are stored on-site until enough containers are collected to fill a 40-foot-long box trailer. The collected consumer electronics are recycled; fluorescent bulbs are collected and handled by a licensed waste hauler. Since CTDEP was considering a ban on these materials being delivered to a waste-to-energy facility, an area was included to collect these materials at the DTM waste facility.

Waste oil, oil filters, antifreeze, and automobile batteries are collected in appropriate containers under a three-sided concrete-block building and recycled by licensed facilities within the state.

The give-and-take center is adjacent to the waste oil area (within the same building but separated by a block wall). Residents are allowed to leave reusable items for others to take and reuse. Larger items such as bicycles can be deposited on a paved pad outside the building area.

Scrap metal is deposited by residents over a retaining wall directly into a rolloff container. Town employees sort any unacceptable waste from the container using a rubber-tired grapple. Once the container is full, it is delivered to a local scrap-metal recycling facility.

Bulky items such as furniture are deposited by residents over a retaining wall onto a paved pad. The items are size-reduced using the grapple and/or a rubber-tired loader and are loaded into a rolloff container for delivery to the SCRRRA waste-to-energy facility.

Construction debris that can be size-reduced and sent to the waste-to-energy facility is handled similarly to the bulky items. Metal items are recycled in the scrap-metal container, and other construction debris is deposited by residents into a 2-cubic-yard container. This small container is transferred to a 100-cubic-yard transfer trailer, which is hauled to a Subtitle D landfill in Massachusetts.

Demolition debris is deposited directly by the residents in the 2-cubic-yard containers discussed above.

Mobile homes and boats are included as personal property under Connecticut law, requiring the town to take possession of and store these items for 15 days if they are abandoned. The DTM waste transfer station includes an area where these items can be stockpiled during this waiting period. Once the waiting period has expired, the town has the mobile homes inspected for asbestos (and has it removed if found) and dismantles the mobile home or boat, recovering and recycling as much material as possible. The remainder is deposited in the 100-cubic-yard trailer and deposited in the landfill. The dismantling occurs on days when the transfer station is closed to the public. If these items have any value, the mobile home park or boat yard typically will keep them as payment for back fees.

The Approach

A design-build (DB) approach was used to meet an ambitious construction schedule and maximize the use of town forces for construction.

CDM performed the vertical construction, such as the buildings and retaining walls; installed the new water system; rehabilitated the existing equipment garage (new roof, electrical service, concrete floor, and paint); put in the site security fencing; and installed new underground electrical service. The town's Department of Public Works employees performed horizontal construction, such as site work, building and wall excavation, stormwater system installation (including piping and a new detention basin), installation of a new septic system, grading, paving, and landscaping.CDM and town crews worked side-by-side to complete the project within schedule—prior to the closure of Welles Road Bulky Waste Landfill. Construction began in the spring of 2002, and the facility was operational by early September of the same year. The DB approach not only expedited construction, but saved the town money since detailed bidding documents were not required. According to Gary Schneider, the Town of Groton's Public Works Director, "Using a partnered DB approach, we reduced approximately 10% of the facility's cost and completed the project faster than if we had to conduct a design-bid-build process."

The Facility

Since the facility's completion, the DTM transfer station is more efficient and user-friendly. The facility has been operational for about two years now. It is open Thursday through Sunday, serving an average of 600 residents a week. The facility was immediately accepted by the town's residents, traffic flow was eased and congestion reduced, and waste that was previously landfilled is being successfully diverted.

Operation of this transfer station offers the residents of Groton the ability to dispose of many items not commonly collected curbside, while maximizing the reuse of items typically disposed of in the wastestream. Potentially toxic or dangerous materials are removed prior to disposal, and recyclable or reusable materials are removed from the waste, saving the town money in terms of their ultimate disposal costs.

Gary Schneider remarks, "Since the DTM transfer station's completion, we have seen a remarkable increase in the amount of materials that we are able to recycle. Currently, we send approximately 25% of the materials to a waste-to-energy facility and 11% to a landfill. The majority is recycled." He adds, "Before this new facility was completed, we sent almost all of the waste to the landfill. We have reached our goal to reuse and recycle as much DTM waste as possible."

The woodwaste chipping operations have been particularly successful. The town is able to control the content of what is chipped and make the end product a usable commodity. Through the use of the SCRRRA tub grinder, this material that was previously landfilled is now beneficially used.

The facility also maximizes the amount of materials that can be dropped off by residents by being flexible. It can be adapted to changing materials, seasonal variations in wastestreams, and future regulatory requirements.

Difficult-to-manage wastes in Groton, CT, are not difficult any more.

Nancy M. Oram, P.E., is CDM project manager in Wethersfield, CT, and Gary Schneider is Town of Groton (CT) public works director.

MSW - September/October 2004