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.. ItWSPECTION REPORT - PAGE 2 FILE NO. M-83-141 DATE: October 24, 1985 OBSERVATIONS OF IMPORTANCE: 1. The purpose of this inspection-was to investigate the site hydrology and geo-hydrology as per the required permit amendment stipulations. The inspectors were accompanied by Mr. Steen during the inspection. 2. The tailings disposal area and proposed tailings damsite were inspected. It was discussed that the facility was to be constructed with a geomembrane liner. It was noted that several bedrock and large boulder areas would need to be excavated and/or prepared to serve as an adequate foundation for the liner. The liner should be installed in a manner to avoid puncture from rocky areas. Slash, slumps and timber should also be removed. 3. The tailings area will have a diversion ditch just below the road to divert any surface runoff. It should be noted that the drainage area above this site is small as it is on the top of the ridge. 4. Monitoring of the tailings disposal area was discussed. It was originally proposed to install monitoring wells along the road below the tailings dam. It was discussed that the operator should investigate the feasibility of a perforated drainpipe leak detection system underneath the liner and base of the dam. Either of these systems, the leak detection drains or drilled wells, would be acceptable to the Division in terms of monitoring. 5. The old USBM test wells are located down gradient/side gradient from the Hazel A adit. These wells will serve as adequate monitor wells to determine any groundwater effects from underground storage of excess tailwater in the Hazel A adit. Water samples should be taken according to EPA protocol and analyzed for pH, temperature, TDS (or EC), sulfate, iron, copper, lead, zinc, mercury, arsenic, cadmium, xanthate, pine oil (oil and grease), or other chemicals which may be used in the milling and floatation process. 6. Baseline samples should be taken prior to mill tailings disposal. Monitoring samples should be taken at least quarterly during the operation. Sample data should be submitted to the Division with the required annual report, Please refer to stipulations as finalized. 7. The bulk head at the Hazel A adit is a buttressed heavy timber sealed underground dam approximately 4 feet in height. Failure of this structure from overtopping or pressure head due to backwater is unlikely. To assure that this structure is stable it should be inspected and certified by a registered Professional Engineer prior to storage of excess tailwater. Mr. Steen stated that it is possible that the height of this underground structure may be increased by 1 or 2 feet. The stability of this increase should also be certified by a registered Professional Engineer, if constructed.