Laserfiche WebLink
Description of Water Monitoring <br />The flow in Harvey Gap Drainage originates as Farmers Irrigation ditch water being discharged from <br />the Harvey Gap Reservoir during the imgation season from April 15 to October 15. From October 15 <br />to Apri115, a base-flow of approximately 0.5 cfs seeps through the dam's outlet system. The 0.5 cfs base <br />-flow during the winter commonly freezes over. When the level ofthe reservoir is drawn down, the base <br />-flow is reduced and has even dried up completely. <br />A six foot Pazshall Flume is located about 50 feet from the outlet structure of the dam. At the discharge <br />of the weir, the water drops about 3 feet. Samples for field pazameters as well as chemical pazameters <br />aze collected as the water drops offthe end of the weir. The flow is measured using the weir's flow rule. <br />At the mouth of Harvey Gap, about 4500 feet downstream of the six foot weir, the Farmers Irrigation <br />Ditch is lined with a concrete structure that divides the ditch into the East Lateral and the West Lateral. <br />The concrete structure allows for adjustment of flows to the East and West Laterals as required by the <br />irrigation users each week. Samples for field and chemical pazameters aze collected right above the <br />division of the East and West Laterals. <br />About 750 feet downstream of the concrete structure in the East Lateral there is a five foot Parshall <br />Flume. A three foot Pazshall Flume is located just below the concrete structure in the West Lateral. <br />Flows are read from the flumes' flow rules and added together for the total below mine flow. <br />Below Harvey Gap Reservoir Dam is an azea of water seeps that flow through a culvert under County <br />Road 237. A 60 degree V-notched boazd has been placed in front of the culvert that goes under County <br />Road 237. The V-notched boazd is used for flow measurement. Samples are collected in front of the V- <br />notched boazd. <br />A monitoring well (Geotech Well) was drilled at the toe ofthe approved waste disposal site. It is 23 feet <br />deep, down to bedrock. The well has produced no water therefore no samples have been collected. The <br />well was reclaimed in June of 1995. <br />A four inch steel pipe has been placed through the portal seals extending to the surface. If water from <br />underground is dischazged through the pipe due to gravity drainage from the mine, the discharge will <br />be monitored once a month for conductivity, flow, pH, and temperature. A lab sample will be obtained <br />once a yeaz if a discharge occurs to be analyzed for the chemical pazameters listed in the DMG Mining <br />and Reclamation Permit. There has been no discharges of water from the steel pipe as ofthe date of this <br />report. Air flow is either into or out of the pipe when the cap is removed. <br />The monitoring program includes the reporting requirements of Colorado Discharge Permit System <br />Industrial General Permit Facility Number COG-860019 (CDPS Permit), which is included in this report <br />by reference. Eastside Coal Company, Inc. has notified the Water Quality Control Division that the <br />Sediment Pond SP-1 has been reclaimed and as a result the discharge point under the permit has been <br />removed and requested the permit be terminated. This action was taken in January, 2002. The CDPS <br />Permit expired on June 30,2002 and was not renewed by Eastside Coal Company, Inc. <br />Page 2 of 22 <br />