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SENT BY:Commerce ;12- 9-91 3:22AM 4 2 position, pacific Energy a£fexs the summary points presented immediately below, followed by specific and detailed technical considerations . • Condensate returned to a landfill does not add to the amount of liquid normally existing in that landfill since all such condensate originates from liquids in the landfill itself . That is, the condensate returned simply puts back a portion of what has been taken out. The operation of �the gas processing facility provides a net drain of liquid from the landfill even while returning some proportion of the condensate. • Total quantities of condensategenerated during the extraction and processing of landfill gas are exceedingly small. They represent about 0.1 to 0.3 percent of the total moisture content of a typical ].andfill over a one- year period. Returning or not returning condensate to a landfill can have little or no bearing upon whether leachate intercepts and contaminates the groundwater. e. Leachate and condensate are very different in character. Leachate is the linuid formed in the wastes due to decomposition and xater infiltration/percolation. Condensate is vapor formed from the leachate, and contains almost exclusively volatile chemical species. Leachate is a highly concentrated mixture and poses potentially serious environmental risks if discharged into the environment . Condensate, in contrast , is much more like drinking water than it is like leachate. Contaminant concentrations in leachate are typically in the thousands , or even tens of thousands of parts per million of volatile, non- volatile, and ionic substances. Condensate typically has a few tens or hundreds of parts per kiLjjj= of volatile substances. e Returning or not returning condensate to a landfill can have little bearing on whether leachate will reach froundwater. If condensate is removed from a land ill and not returned, most species in the leachate are likely to simply become very slightly more concentrated as a result. This means most contaminants are left behind and will intercept the groundwater anyway--whether condensate is returned to the waste or not. The important step is thus to control leachate migration rather than restrict condensate return.