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Work Plan for Refined Plume Definition and Management of Floating Product-7500 W 11th St., Tracy, CA. Page 69 .. The 6-in. "Well Clincher," or cap, fits over and seals the top of the well casing. It has expandable pass-through fittings for the air-supply tube connected to the skimmer pump assembly and for the product discharge hose. This arrangement allows the pump depth to be adjusted easily. A 5-micron coalescing and auto drain filter/regulator device is installed in the air-supply line to each pump system to filter the compressed air and regulate the operation of the pump. The air line from the outlet of the filter/regulator to the pump is 1/4-in. diameter polyethylene tubing. The air inlet side of the filter/regulator that connects it to the air supply and the +— overfill protection device (see below) is equipped with "quick connect" fittings. The regulator allows the pump operating pressure to be set according to the depth at which the pump operates. A visual indicator on that equipment provides an alert when the filter elements need to be serviced. From the well clincher at the top of the casing, the pumped product will be discharged through a 3/8-in. diameter flexible Buna-N® discharge hose into the 5,000-gallon holding tank located in a fenced area of Capitol Furniture's parking lot. The holding tank will be equipped with an electro-pneumatic overfill protection device, which is installed between the air source and the filter regulator. When the fluid in the tank reaches a pre-designated high level, it activates the shut-off valve to the air supply and thereby shuts down the system. After the storage tank is emptied, a manual restart button is pressed and the overfill protection device reactivates the system. Compressed air is supplied to the three well skimmer pump array by a free-standing, mobile, 5-hp, electrically-powered air compressor. As a conservative feature of the system design and to avoid system upset due to water condensation in the pneumatic pump controls in freezing high-humidity weather conditions, which periodically occur in the Tracy area, a membrane " dryer is installed at the outlet from the air compressor. The system is capable of pumping a maximum 2.2 gallons per minute from each well. �. However, after the first approximate one hour of operation after system start-up, during which accumulated LNAPL in the wells will be evacuated, the discharge rate will be reduced to a small fraction of that value as floating product migrates very slowly into the well. In fact,' for the greater part of the operating life of the system, it is expected that the controllers will shut off pumps because of the absence of sufficient LNAPL floating on the water table in the wells. 9.4.3.2 Surface Equipment Enclosure The holding tank, air compressor and other large system components of the skimmer pump- based floating product remediation system will be located in a fenced-in area, measuring approximately 30 ft. by 40 ft. in the southeast corner of the asphalt-paved parking lot at 7501 West Eleventh Street. A 21-in. high concrete curb will be constructed around the perimeter of the enclosure to provide for secondary containment for 5,000 gallons of LNAPL and contaminated groundwater should the holding tank be breached. To ensure that the bituminous macadam paving of the enclosure will retain any spilled liquid, it will be treated sic