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E <br />Mr. Robert McClellon <br />March 7, 2011 <br />Page 6 <br />Table 1— Summary of Original and Current Setbacks from Edge of Waste (See Fig 21 <br />Probe ID <br />Original Liner Setback <br />Relocation <br />Offset <br />(Ft. and Direction) <br />Current Liner <br />Setback <br />GP -8/8R <br />121 <br />28 West <br />135 <br />GP -9/9R <br />13 <br />33 West <br />46 <br />GP -10/ <br />1OR <br />62 from WMU FU -06 and <br />164 from WMU <br />D-02 <br />26 West <br />62 from WMU FU -06 <br />andl68 from WMU D-02 <br />GP -11/11R <br />30 <br />19 South <br />49 <br />GP -12/12R <br />20 <br />25 South <br />45 <br />The setback from the liner (edge of waste) for Probes GP -8 and GP -10 has not changed <br />significantly. Of the original Probes GP -8, 9, and 10, Probe GP -9 was the probe closest to <br />the edge of waste at approximately 13 feet from the western edge of WMU D-01 and is now <br />approximately 46 feet from the edge of waste (GP -9R). Several exceedences occurred in <br />Probe GP -9 when it was in its original location. However, there have been no exceedences <br />since GP -9 was relocated 33 feet to the West to a location roughly 50 feet from the edge of <br />waste. Therefore, based on the relocation of GP -9, it appears that an approximate 50 -foot <br />offset is sufficient and any further offset should be acceptable. Based on this information, to <br />address the EHD's concerns, Forward proposes that the edge of waste for the expansion will <br />be a minimum of 75 feet from the property boundary and the new probes will be installed <br />along the property boundary. <br />Conclusion <br />In summary, the new LFG migration probes for the landfill expansion will be designed in <br />accordance with the CCR Title 27 criteria. The edge of waste for the expansion will be a <br />minimum of 75 feet from the property boundary and the new probes will be installed along <br />the property boundary. LFG migration will be addressed by the installation of a composite <br />liner system and a properly operated and maintained GCCS. <br />Recent results of probe monitoring at Forward indicate that the installation and operation of <br />new wells in the lined area and in the old Austin Road Unit have successfully expanded the <br />radius of influence of the GCCS system to collect LFG previously detected at the existing <br />probes and are therefore addressing LFG migration as designed. Barring unexpected <br />conditions, the ongoing GCCS improvements will demonstrate that given the site geology, <br />