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5-10 below the liner and connected to the horizontal wells with laterals. The horizontal wells will be extended through the edge of the in-place refuse prism on the north face to extract landfill gas while the north side of the site is filled. When the refuse in adjacent waste cells reach the height of the horizontal well stub -outs on the south face, the horizontal well can be extended to collect the gas generated in the new cells. This end of the horizontal collector will be connected to the looped header system located along the Austin Road Unit's southern edge. Details of the landfill gas extraction system are shown on Drawing 12. As the new cells are filled, additional vertical extraction wells will be installed in phases to control surface landfill gas emissions. These wells may be extended as the fill progresses in the cell, or may be abandoned and replaced with new wells when the fill reaches the final grade elevation. As the fill progresses above the existing and now -lined refuse prisms, additional vertical extraction wells will be placed into the upper portions of the landfill to achieve the proper spacing required for surface emissions control. Permits will be obtained from the SJVAPCD and other appropriate agencies for the construction and operation of each phase of gas system development. The current landfill gas migration monitoring system at the Forward Landfill consists of 29 perimeter compliance probes defined as GP -01 through GP -06, GP -7R through GP -12R, GP- 1ORB, and GP -13 through GP -28. It should be noted that probes GP -7 through GP -12 are still in-place but are no longer part of the compliance monitoring program and are not included in the total number of probes (i.e., 29 probes). These probes have since been replaced with probes GP -7R through GP -12R, GP-10RB, and GP -28 to accommodate the revised facility boundary (additional 184 acres) of the Forward Landfill. It should be noted that probe GP -26 is located between probes GP -24 and GP -25, and probe GP -27 is located between probes GP -16 and GP -17 (see Figure 10 for the locations of the probes that are a part of the compliance monitoring program). The locations of all probes (including GP -7 through GP -12) are shown on Drawing 11. This system is further discussed in Section 7.5.1. As previously mentioned in Section 4.1, the LFGTE plant located at the northwest portion of the site, which was formerly owned and operated by Covanta and then ownership was transferred to Forward Inc. in 2011, has been shutdown as of October 23, 2012. SJVAPCD has cancelled its associated operating permits (Appendix B). A new LFGTE facility permitted in October 2011 and developed by Ameresco (a third panty renewable energy developer) will replace the closed LFGTE. It is anticipated that the new LFGTE plant will become operational in spring 2014. The new LFGTE facility will be located just east of the existing flare station in the northeast corner of the site (Drawing 11). In addition to the new LFGTE plant, Ameresco is proposing to install a new, small high-temperature, enclosed flare station associated with the landfill gas pretreatment system for the internal combustion engine units. The LFGTE is also described in Section 7.5.1.1. Forward Landfill SWT Engineering Joint Technical Document - April 2014 z:\projects\allied waste\forward\five year permit rvw 2013\jtd-5 yr pr 2013\text\sec 5_final.doc