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Description of Water Monitoring The flow in Harvey Gap Drainage originates as Farmers Irrigation ditch water being discharged from the Harvey Gap Reservoir during the irrigation season from April 15 to October 15. From October 15 to April 15, a baseflow of approximately 0.5 cfs seeps through the dam's outlet system. The 0.5 cfs baseflow during the winter commonly freezes over. When the level of the reservoir is drawn down, the baseflow is reduced and has even dried up completely. A six foot parshall flume is located about 50 feet from the outlet structure of the dam. At the discharge of the weir, the water drops about 3 feet. Samples for field parameters as well as chemical parameters are collected as the water drops off the end of the weir. The flow is measured using the weir's flow rule. At the mouth of Harvey Gap, about 4500 feet downstream of the six foot weir, the Farmers Irrigation Ditch is lined with a concrete structure that divides the ditch into the East Lateral and the West Lateral. The concrete structure allows for adjustment of flows to the East and West Laterals as required by the irrigation users each week Samples for field and chemical parameters are collected right above the division of the East and West Laterals. About 750 feet do~mstream of the concrete structure in the East Lateral there is a five foot Parshall flume. A three foot Parshall Flume is located just below the concrete structure in the West Lateral. Flows are read from the flumes' flow rules and added together for the total below mine flow. Below Harvey Gap Reservoir Dam is an area of water seeps that flow through a culvert under County Road 237. A 60 degree V-notched board has been placed in front of the culvert that goes under County Road 237. The V-notched board is used for flow measurement. Samples are collected in front of [he V-notched board. A monitoring well (Geotech Well) was drilled at the toe of the approved waste disposal site. It is 23 feet deep, down to bedrock. The well has produced no water therefore no samples have been collected. The well was reclaimed in June of 1995. A four inch steel pipe has been placed through the portal seals extending to the surface. If water from underground is discharged through the pipe due to gravity drainage from the mine, the discharge will be monitored once a month for conductivity, Flow, pH, and temperature. A lab sample will be obtained once a year ifa discharge occurs to be analyzed for the chemical parameters listed in the DMG Mining and Reclamation Permit. There has been no discharges of water from the steel pipe as of the date of this report. Air flow is either into or out of the pipe when the cap is removed. The monitoring program includes the requirements of Colorado Discharge Permit System Industrial General Permit Facility Number COG-860019 (CDPS Permit). Page 2 of 17 S.Na o/ vr/