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• (Page 2) • MINE ID # OR PROSPECTING ID # M-99-002 INSPECTION DATE 10/20/99 INSPECTOR'S INITIALS ACS This inspection was conducted to observe ground water sampling operations being conducted at the Yankee Gulch Project. The approved Groundwater and Surface Water Monitoring Plan requires collection of baseline or pre-operational samples for characterization of ambient hydrologic conditions. The ground water characterization plan includes monitoring of 24 wells. New multiple completion wells 29-4, 21-9, and 21-3 were installed in July 1999. During this inspection, sampling of well 29-4 was observed. Well 29-4 has been installed to the south of the location illustrated on Figure 1 of the Groundwater and Surface Water Monitoring Plan. Pre-existing well 29-2 has been abandoned, and a multiple completion well installed on the new well pad. The B-groove completion in the multiple completion well was inadvertently cemented through and has been replaced by a single completion B-groove monitoring well on the same pad. The relocation of the 29-4 pad to the south and the abandonment of the 29-2 well pad was done to avoid runoff and drainage problems at the old pad which was located at the confluence of two draws. The relocation of the well pad was discussed in advance with the Division of Minerals and Geology (DMG) and Bureau of Land Management. It was determined that the well pad relocation could be incorporated into the site reclamation permit through the well completion report and location map to be provided under Rule 3.1.7(7)(b) of the Hard Rock/Metal Mining Rules of the Mined Land Reclamation Board. The well completion report and location map will be submitted to DMG with the first data set. The monitoring wells have been fitted with dedicated nitrogen gas lift pumps installed in the screened interval of each completion. The gas lift pumps are used for micro purging and drawing samples from the wells. The tubing through which the well water is carried is dedicated in each well completion except for a short valved section that is attached during purging and sampling operations. The short tubing section that is reused at each well is decontaminated between samples by flushing with nitric acid. Also, several quarts of well water are passed through the tubing during micro purging and prior to collection of a sample. There is no filtering equipment to decontaminate because disposable in-line filters are being used. The approved Groundwater and Surface Water Monitoring Plan discusses the use of dedicated bladder pumps in each well. As stated above, the Operator has installed nitrogen gas lift pumps. The use of gas lift pumps may be incorporated into the reclamation permit through the well completion report. Across section and description of the pumps must be included in the report. The depth to water is measured from the top of the casing in each well using an electric sounding graduated tape. The sounding device and tape are decontaminated between each use by rinsing with deionized water and drying as needed using paper towels. An alarm sounds when the sounding probe is in contact with water. To assure that the water level in the well is not drawn down during micro purging and sampling, the probe is set slightly below the well water surface and the alarm sounds continuously. If the alarm stops, indicating draw down, pumping is temporarily discontinued and then adjusted such that draw down is eliminated. Draw down during micro purging and sampling were much less than the 0.1 meters allowed in the approved plan for each of the wells sampled during this inspection. Micro purging of wells 29-4-Uinta and 29-9-A-groove was observed during this inspection. Initially, one tubing and pump volume of water are evacuated and tested for temperature, pH, and conductivity. Then a second volume of water is evacuated and tested. If the field parameters do not deviate, the well is sampled. Otherwise, the well is micro purged until the parameters stabilize before a sample is collected. The wastewater generated during purging and sampling is collected into a plastic tank and is dumped into the lined collection pond at the test mine facility.