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Mr. David Berry October 26, 1988 Page 8 CYVCC RESPONSE: The October, 1988 mercury concentration for Well 008-AV-1 was 0.3 ug/1, only slightly above the detection limit of 0.2 ug/1. While the conductivity levels of Well 008-AV-2 did increase in 1987, the dissolved solids concentration did not increase. Therefore, no increasing trend in the dissolved solids load to the alluvial/surface water system as indicated. MLRD CONCERN: Spoil Sorinas Two springs were sampled during the 1986-1987 water year. These exhibited relatively high values for electrical conductivity, total dissolved solids (M3-87-1), sulphate (M3-87-1), silver (M3-87-1), zinc (Mil-87-2), iron and manganese. The suspended solids concentration is relatively high for M3-87-2. We recommend that when samples are collected for low flow sites such as these, the sample should be filtered. This should be documented in the data base to avoid any confusion during the data analysis phase. It is our understanding that the previously identified springs (M3A, MOB, M3C, M3D) were dry during the last water year. Please notify us if this is not correct. CYVCC RESPONSE: The water quality of the springs is consistent with or better than that expected from spoil springs. Care will be taken in the future to minimize suspended solids concentrations of spring samples, although field conditions sometimes make it difficult to prevent suspended solid contamination. This is due to the low flows encountered from the various springs. All parameters indicated as dissolved are from a filtered aliquot of the sample. MLRD CONCERN: Surface Water Three stream sties are monitored; one by CYCC and two by the USGS. As expected, relatively elevated values are reported for electrical conductivity, total dissolved solids, sulphate, iron and manganese. Both station 900 (Foidel Creek) and Station 29 (Middle Creek) may indicate an increasing trend for electrical conductivity. We agree that much of the impact is attributable to the larger mine complex upstream from Mine No. 3. It is also possible that same of the increase may be explained by recent low flows; however, these issues must be examined in greater detail before specific conclusions regarding material damage can be formulated.