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Logan Wash Mine TR No. 8 Bench, the mine water will continue to serve as a recharge source to the unconfined aquifer but will infiltrate into the unconsolidated materials at a different infiltration point than that which currently exists. If the mine not been constructed, it is likely that at least a portion of the groundwater flowing through the bedrock in the area of the mine would have naturally discharged from bedrock to nearby unconsolidated colluvium that comprises the local, unconfined aquifer down 'gradient of the mine. Therefore, the existing hydrologic balance is not expected to be impacted by the change in discharge location. Mine water discharge from the Research Mine (Outfall 002) may occur on an intermittent basis and can be controlled through valves near the portal. Any intermittent discharge from the Research Mine is expected to be minimal and not significantly affect the hydrologic balance in the vicinity of the mine. Termination of the CDPS permit will streamline management and administration of the Logan Wash Mine for both regulatory agencies and OOSI without a reduction in environmental protection of surface water and groundwater resources. 4.0 Water Characteristics 4.1 Mine Discharge The discharge rate of mine water from the L -1 portal (Outfall 001) was periodically measured prior to the most recent CDPS permit and has been measured continuously with an electronic flow meter since the new permit became effective in 2011. The average discharge rate from the time the flow meter was installed in August 2011 to the present is 2.71 gallons per ininute (gpm). The range of discharge during this period was 1.62 to 3.35 gpm. Historical data from the period 1996 to 2010 show that the discharge rate ranged from 1.5 to 30 gpm. The average discharge rate since the L -1 portal was sealed in 2003 to 2010 was 3.47 gpm. As previously mentioned, no discharge has occurred from Outfall 002 since the Research Mine portal was sealed in 2004. Prior to sealing the portal, the discharge rate of mine water from the Research Mine (Outfall 002) was historically intermittent and commonly occurred during spring snowmelt. Discharge data from the period 1993 to 2001 show that the discharge rate ranged from 0.04 to 54.6 gpm and the average was 2.36 gpm. 4.2 Water Quality Water - quality data for the Logan Wash Mine LW -001 mine water is summarized in Table 1. Analytical data for Outfall 001 (sample ID LW -001) was collected sporadically prior to issuance of the latest CDPS permit in March 2011. The current permit requires chemical analysis on a monthly basis, with the exception of the months November through March when access to the mine can be difficult if not impossible due to excessive snow pack or extremely muddy conditions. In addition, OOSI has been collecting samples of the LW -001 mine water, the retort mine water, and groundwater at well LWCW -lA for an extended analytical suite on a semi- annual basis since 2007. Western Water & Land, Inc.