Landfills are high-tech operations now. It's no longer acceptable to find an isolated tract of land not too far from an urban area, dig a pit, then build a mountain of garbage. Modern landfills are engineered and built as a series of cells. The cells include liners of plastic membranes and watertight clay on the bottom. At the end of each day, earth covers the trash deposited in the cell, to keep animals away.
When a cell is full, a thick cap of watertight clay is added at the top of each cell. This impervious clay blocks rainwater from seeping into the garbage and then into adjacent groundwater. Intricate plumbing systems are installed at different levels, to capture and release gases from decomposing waste before pressure builds up and cracks the clay covering.
The plumbing threaded through the landfill also collects the juices ("leachate") that are squeezed out of the garbage, plus groundwater/rainwater that manages to seep into the landfill and become contaminated. The pipes carry the leachate to wastewater treatment facilities, where the contaminants are separated from the water.
Sometimes the contaminants from the leachate are incinerated, and ash is buried in a specialized landfill for that product. In other cases, concentrated sludge from the water treatment plant is carried back to the landfill and buried there. Once a landfill is oficially closed and sealed with clay at the top, the waste is isolated from the surrounding environment - at least in theory.
After several decades of decay, bacterial decomposition of waste should become minimal. Until then, surface inspections can ensure if the clay cap has settled or cracked, while monitoring wells can measure if the membranes, clay, and leachate collection processes actually prevent plumes of pollution from contaminating groundwater.
Virginia has roughly 60 solid waste landfills still in operation. There are 134 separate counties and cities, so obviously solid waste management is now a regional operation. In 1993, the General Assembly mandated in a law known as "HB 1205" that existing landfills that did not need new requirements must be closed. Old landfills would be permitted to continue accepting waste until their existing facilities were filled, but no horizontal expansion of old landfills would be permitted. All new cells, at old or new landfills, would have to meet stricter requirements for liners, clay caps, gas release systems, and monitoring.
If the recommendations in the Prioritization and Closure Schedule for HB 1205 Landfills report (issued July, 2000) are implemented, the Virginia Department of Environmental Quality (DEQ) could force the two Virginia counties on the Eastern Shore out of the landfill business.
The original proposal in the General Assembly would have created new fees to compensate those affected by the more-stringent environmental mandates. The cost to close a landfill is relatively clear, compared to the social cost (especially in human health) if an unsafe site is permitted to continue operating. Asking a small rural county to absorb those costs directly was not the original plan of the General Assembly, but Governor Gilmore effectively blocked imposition of what he perceived as new taxes.
Owners of the landfills complain about the requirements being too strict, too expensive, and too fast. Northampton County claimed it would cost $3 million to close the Oyster Site landfill by 2010. Accomack County has two landfills. According to DEQ's initial plans, "Bobtown" South should have closed in 2005 and "No. 2" should close 15 years later. Current plans are to close in 2012 and 2017.
The Oyster Site landfill in Northampton County was to be "closed" in 2010, but it is still operating. (Accomack County residents who live nearby tend to haul waste to the Northampton County landfill, because the "tipping fee" is lower.) Whenever the Oyster Site closes, the landfill will be watched for decades afterwards. Leachate continues to seep from the garbage as it gradually compacts and chemically changes. Decomposition of organic material is slowed in the anaerobic (oxygen-deprived) environment, but not stopped completely. Anecdotal stories tell of landfills being opened after decades, and newspapers had hardly turned yellow. Hot dogs with mustard looked just as good as the day they were tossed in the trash. Decomposition takes time, but all that material will gradually degrade.
In addition, landfills create methane and other types of gas that bubble up to the surface and can crack the cap, if the pressure is not released. In addition to lechate pipes, modern landfills have plumbing for gas collection. If you drive Interstate 66 near Fair Oaks Parkway after dark, you can see the flare used to burn the methane coming from the now-closed landfill adjacent to the interstate.
The two Eastern Shore counties could have built new landfill facilities to replace the ones being forced to close. However, there are great economies of scale in landfill construction and operations. It's inefficient to build small facilities, and two rural counties could not afford to borrow the necessary funds for a large high-tech facility that would always require taxes for an operating subsidy. The experience in Page County offers a lesson. The county leased its Battle Creek landfill, and then permitted the operator to grossly exceed the 250 ton/day limit in ordder to generate greater volume and thus more fees. DEQ ultimately revoked the permit for that landfill, and Page County will struggle to repay the costs for decades to come.
On the Eastern Shore, as at Page County, there's just not enough population or industry to make a large landfill facility an attractive investment. The Eastern Shore counties have not found regional partners to share the cost of a regional facility. The Hampton Roads communities already have a regional disposal authority; they were unwilling to ship garbage across the Chesapeake Bay Bridge. The greatest waste disposal challenge across the Maryland line is processing chicken manure (and dead chickens), not municipal solid waste.
Northampton County chose to build a $2 million transfer facility, where local garbage collection trucks could deposit waste and more-efficient vehicles could transport the waste outside the county to a sanitary landfill. Transfer stations are temporary collection points. Garbage trucks pick up the waste, and at the transfer station it's moved into large tractor trailers.
Virginia Beach used a creative process to close its landfill. It compacted and piled solid waste into Mount Trashmore, building the cells vertically over 60 feet high until creating the highest point in the city. After closing the landfill and capping it with clay, Virginia Beach made it into a public park. The garbage is decaying underneath the clay, burping gases out the vent pipes regularly, but the city converted a waste site into a recreational asset. After closing the landfill, the city shipped its solid waste to the Southeastern Public Service Authority (SPSA) waste-to-energy plant in Portsmouth and the SPSA's landfill in Suffolk.
In the 1980's, Arlington and Alexandria realized they were running out of landfill space for disposal of solid waste. They joined together to build a joint waste-to-energy facility, implementing a new technology to solve an old problem. Fairfax has also built a waste-to-energy facility at Lorton. The county closed the I-95 landfill, and directed all municipal solid waste to the incinerator.
In Fairfax County, the trailers are a distinctive tan color, and are commonly seen carrying loads from the transfer station at the old I-66 landfill to the waste-to-energy facility (incinerator) at Lorton or the Prince William County landfill. On the Eastern Shore, garbage from a transfer facility could go to the regional Southeastern Public Service Authority waste-to-energy facility or landfill, especially if the $10 toll for one-way traffic across the Chesapeake Bay Bridge-Tunnel is reduced.