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Dan Mathews 2 June 8 2006 3. DMG -The baseline groundwater data for the Alluvial Wells No. 1 through No. 6 is presented in the McClave permit in Tables 4.2-1 through 4.2-5. There appears to be some baseline data missing or possibly it was never collected. The current minimum requirements for baseline groundwater information are given in Rule 2.04.7 (1). No data are given in Table 4.2-1 through 4.2-5 for Alluvial Well No. 3 (possibly dry), and iron and manganese analyses are not provided for Alluvial Well Nos. 5 and 6. No baseline data could be located for newer wells GW-7 and GW-8. DMG -There is also uncertainty as to which of the original alluvial wells (for which baseline data has been provided) correspond to the wells in the current approved program. This needs to be clarified in the permits. In the Munger permit, Table 2.5-1 lists groundwater monitoring site numbers and corresponding well numbers but this does not dear up the confusion regarding which of the "GW" wells were monitored during the baseline data program. For wells in the approved program, it is unclear if Alluvial Well No.s 1 and 6 correspond to GW-1 and GW-6, respectively. Well G W-3 appears to correspond to Alluvial Well No. 2. CAM -The alluvial wells are confusing since they are not discussed in detail in the permit, and there are no completion diagrams for them. Some of the alluvial wells are located close to the groundwater monitoring wells, but they are not the same. For example, AW-6 was near GW-3. However, when you compare baseline data for the two, they are remarkably different, GW-3 conductivity is 7,000+, AW-6 is 1,250. To eliminate the confusion between the alluvial wells and the ground water monitoring wells, a paragraph was added to the Groundwater Quality Monitoring Program shown on page 4-17, and a double asterisk was added to Tables 4.2-1 thru 4.2-5 stating the AW do not equal GW monitoring wells. DMG -Because the alluvial sediments associated with East Salt Creek have been designated as an alluvial valley floor, certain surveys and geohydrologic data are required. Please see Rule 2.06.8 (4)(c)(iv). At a minimum, well completion logs and drill logs should be submitted for all monitoring wells that are included in the approved monitoring plan. If sufficient data exist, a groundwater contour map should be developed and updated annually with the future AHR submittals for East Satt Creek Alluvium. Figures 4.1-3 through 4.1-6 present boring logs (with well completion information) for four of the alluvial wells, which appear to correspond to G W-2, G W-3, GW-4, and GW-5. No other well completion logs or drill logs are presented in the permit document or AHR for any of the other monitoring wells. CAM -The monitoring wells at the mines are GW-1 through 8. As requested thru the 2006 permit renewal application, GW-2, 4, 7, and 8 are scheduled to be sealed as they are no longer actively monitored. Atypical well completion log is presented in Figure 4.1-7, and includes surface elevation, type of casing, diameter of casing, total depth of well, perforated interval and formation completed in for the GW wells except there is no perforated interval for GW-1. Old permit data taken from the Munger Canyon permit (Table 4.2-2S) shows the MW series are the same as the GW series wells but the numbering is different. Going forward, the operator will refer to the wells with the GW designation only. See Table 4.2 showing nomenclature clarification for drill holes included in current monitoring plan. Baseline data for the GW monitoring wells is shown in new Table 4.2i. Renamed Figures 4.13 through 4.1-6 using GW designation only. DMG - To clarify these discrepancies, the Division recommends that a new appendix be inserted into each permit or that the existing documents be amended with updated information succinctly presenting the approved groundwater monitoring programs. The nomenclature for each well should be clearly identified and the corresponding baseline data, drill logs and well completion information provided. The water sample location map (Figure 4.2-2) should be updated accordingly and if appropriate a groundwatercontourmap should be developed for the East Salt Creek Alluvium. Please include in the updated appendices, a well completion summary table of active monitoring wells. Please include in the table at a minimum the following information: surface elevation, measuring point elevation, type of casing, diameter of casing, total depth of well, and perforated interval, and formation completed in.