Protecting the Environment
The whole purpose of a landfill is to protect the environment. Landfills are a form of pollution control - the pollution being the waste we generate.
Scientifically designed and engineered landfills were developed to replace unsafe and unsanitary town dumps and incinerators.
Conestoga Landfill employs state-of-the-art technology and has one of the best environmental safety records in the state. As an affiliate of Allied Waste Industries, Inc., Conestoga Landfill has access to the finest, most up-to-date engineering and environmental resources in the industry. The landfill has never had a significant environmental safety problem since it opened in 1992. The Pennsylvania Department of Environmental Protection (DEP) and Berks County inspect the landfill on a regular basis and their reports are available to the public.
Conestoga's staff is well-trained, highly motivated and responsive. The general manager and operations manager provide full-time oversight. A waste coordinator makes sure no inappropriate waste material is disposed of in the landfill. In addition, a full-time environmental compliance officer oversees efforts to control odors, dust, and litter.
Landfill operators recognize their responsibility to protect the environment even after their landfills are closed. The entire Conestoga Landfill is lined. The liner meets all requirements of DEP and the U.S. Environmental Protection Agency (EPA). The lined "cells" in which trash is placed are situated well above the water table. When a cell is filled, it is capped and closed.
The outer liner is made of thick, heavy-duty high-density polyethylene (HDPE) plastic and rests on a layer of compacted subbase soil. Gravel is laid over the outer liner. A network of HDPE pipes is placed in this section as part of a leachate-detection system. A thick layer of clay is placed over this, and then another heavy-duty liner is laid on top. Over this liner sits a geotextile cushion, a layer of gravel, and a network of pipes that collect leachate and send it to an on-site treatment plant.
Leachate - water that has come into contact with trash - is collected and treated in a state-of-the-art facility on site. The landfill is allowed by DEP permit to discharge the cleaned water into tributaries of the Conestoga River. The water discharged into the river is as clean or cleaner than the water already in the river. The treated cleaned water is also used for dust control on roadways within the landfill.
Groundwater is continually monitored for quality at a series of wells. Surface water from the landfill and water in streams surrounding the landfill is sampled and tested. A series of sedimentation basins and a network of pipes collect and route surface water from the landfill to maintain water flow into natural wetlands adjacent to the landfill. The results of the monitoring program have demonstrated that there has been no impact on local groundwater quality from the operation of the landfill.
A network of extraction wells and flares collect and burn off methane gas that is produced by trash as it decomposes. Conestoga is working on plans to use the gas to generate electricity. Probes are placed around the perimeter of the landfill to make sure methane does not migrate off site.
CONESTOGA'S LANDFILL LINER DESIGN
An environmentally sound liner design is a key element of any landfill. The Conestoga liner system offers superior protection for either municipal or residual waste. Conestoga exceeds what is required or expected of a liner system, offering peace of mind to customers who may be concerned with long-term liability issues. A thick clay liner, in addition to double synthetic liners and superior leachate collection and detection systems, comprise the liner profile that is recognized for exceeding state and industry standards.
Precipitation that percolates through landfilled waste, referred to as leachate, is collected and removed through a network of pipes that lie above the primary composite liner. This composite liner consists of a chemically resistant, high-density polyethylene material, which is placed on top of a thick layer of compacted clay.
The leachate detection zone and a secondary liner, situated under the clay layer, provide a completely independent back-up system to verify and ensure environmental integrity.
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GROUNDWATER AND SURFACE WATER MONITORING
Monitoring of groundwater and surface water is conducted to ensure that every landfill site performs as designed and protects the environment. By tracking groundwater and surface water migration patterns, Conestoga can identify, isolate, and resolve potential problems.
In addition, Conestoga has developed effective groundwater monitoring well installation and sampling procedures that help eliminate the common problem of measuring contamination from sources unrelated to the landfill.
Conestoga has more than 10 years of background groundwater and surface water monitoring information for the landfill. Located on the landfill property are 18 perimeter groundwater monitoring wells and five surface water monitoring points.
Groundwater and stream sampling tests are done on a quarterly basis at the Conestoga Landfill. Sedimentation basins are sampled and analyzed semi-annually.
LANDFILL GAS MONITORING AND COLLECTION SYSTEM
The natural degradation of wastes in a landfill produces a mixture of gases (primarily methane and carbon dioxide) that must be monitored and controlled to prevent odors and accumulations that could lead to fire or explosions.
The gases are collected and flared by a network of extraction wells on the property. The system is monitored closely to ensure proper operation and control of gases. Fifteen gas monitoring probes surround the landfill to monitor the potential of gas migration from the facility.
LEACHATE MANAGEMENT PROCEDURES
Leachate is a liquid in a landfill that is produced by either precipitation that comes into contact with solid waste, the natural moisture content of the waste itself that is released during compaction, or the moisture generated from the biodegradation of organic material. The average daily maximum volume of leachate generated at the Conestoga Landfill is calculated to be 50,000 gallons per day.
An on-site reverse osmosis leachate treatment plant, which began operating in 1999, treats leachate generated by the landfill. The treated leachate is carefully monitored and laboratory tested to ensure treatment is in compliance with permitted standards, and is then discharged into the Conestoga Creek. The monitoring and discharge are regulated by Conestoga's NPDES Permit, issued by the Pennsylvania Department of Environmental Protection, Water Management Bureau.