LANDFILL GAS COLLECTION AND CONTROL
The wellfield employs horizontal collectors and vertical wells. A layer of horizontal collectors is
installed at every 10 m (33 feet) of vertical depth as waste is being placed. The horizontal
collectors are located 100 m (330 feet) apart. In all, each area ultimately receives four layers of
collectors. A 610 mm (24 inch) diameter HDPE header loops each area at each layer of
horizontal collectors. Each collector is connected to the header at both of its ends. The
horizontal collectors are up to 750 m (2,460 feet) in length. Vertical risers are installed every
250 m (825 feet) of horizontal length of the collectors. The risers are used for leachate pumping
and supplemental landfill gas extraction.
After completion of filling of Area No. 1, vertical wells were drilled at about 60 m (200 feet) on
center across the top deck. A total of 330 vertical wells were installed in Area No. 1 in 2003.
A single flare station serves the landfill. It incorporates four 85 Nm3
/min (3,000 scfm) enclosed
flares and two 170 Nm3
/min (6,000 scfm) enclosed flares. Total capacity of the flare station is
680 Nm3
/min (24,000 scfm). The flare station is located adjacent to Area No. 1. The flare
station’s blowers directly draw a vacuum on Area No. 1.
Area No. 2 is equipped with five booster blowers, which provide a vacuum on Area No. 2 and
which slightly pressurize the landfill gas for delivery to the landfill gas beneficial uses and the
Area No. 1 flare station.