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<br />Mine water associated with Outfall 001 originates as infiltration water in the upper and lower <br />mine workings, and unless it re-infiltrates by way of other fractures on the mine floor, eventually <br />discharges into a French drain and piping system near the lower portal. Water discharging into <br />the French drain and piping system is piped from just outside of the lower portal down the main <br />waste-rock pile where the pipe daylights into Logan Wash. The official discharge point for <br />Outfall 001 is located approximately 450 ftdown- drainage of the actual mine-water discharge <br />pipe. No discharge is recorded unless water actually flows on the surface to the down-drainage <br />site. To-date, no discharge has been recorded at the 001 outfall. <br />Outfall 002 is located at the Research Mine portal and is also the result of groundwater infiltrating <br />into the mine workings. Outfall 002 is the discharge associated with a 6-inch pipe that originates <br />inside the Research Mine portal area and extends approximately 50 ft outside of the portal on the <br />surface. This discharge is usually measured in gallons per minute (less than 5 gpm) and <br />frequently dries up to no discharge in mid to late summer. The NPDES outfalls are monitored on <br />a weekly, monthly, and quarterly schedule for flow and water quality if flow is present. <br />Historically, Retorts 4, 5, 6, 7, and 8 have collected and discharged groundwater. No significant <br />dischazge has been reported from Retorts IE, 2E, or 3E. Retort mine water from Retorts 4, 5, 6, <br />7, and 8 is piped to an access manhole just outside the lower portal. From this point, the retort <br />water flows through buried pipe approximately 7 miles to the evaporation pond (Pond 1) where <br />water is evaporated. During the summers of 1998 and 1999, enhanced evaporation was <br />conducted at Pond 1 using a pump and fine-mist sprayers. The pump/sprayer system was initially <br />used to manage water generated during the period of combined flow of mine and retort water <br />(May 1997 to August 1998). The enhanced system has not been used during the last several years <br />as evaporation has exceeded retort-water drainage flow rates. <br />3.0 Water Quality and Mine Drainage Discharge <br />Water quality of the retort drainage water at the Logan Wash Mine has been collected <br />periodically within the last several years. Table 1 presents a summary of the retort water quality <br />and the state water quality standards for Roan Creek, the downstream stream segment classified <br />by the Water Quality Control Commission. The table indicates that several constituents in the <br />retort water exceed state water quality standards established for Roan Creek. However, it is <br />important to note that the reported results are "end-of-pipe" concentrations and may not reflect <br />