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SUPIMARY AND RECOMMENDATIONS The Middle Fork and East Middle Fork drainages of Parachute Creek are designated under Segment 11 by the Water Quality Control Commission 1 (WQCC) for setting stream use classifications and water quality JJ standards. These drainages are proposed [o be classified for use as ~ Recreation Class 2, Cold Water Aquatic Life Class 1, Water Supply, and Agriculture. Associated water quality standards have been proposed to protect the proposed designated use. Proposed standards for metals to protect aquatic life appear to be based on an assumed surface water hardness or alkalinity concentration range of 100 to 300 milligrams per litre. Exxon Company USA owns land in both the Middle Fork and East Middle Fork drainage. An analyses of water quality and aquatic life in these basins has been conducted relative to the WQCC proposed use classifications and standards. t MIDDLE FORK AND DAVIS GULCH DRAINAGES J It is the position of Exxon Company USA that based on our analysis the proposed use classifications for the Middle Fork drainage are inappropriate and unsupportable. Water quality data were analyzed to establish background water quality conditions and to identify parameters which have reported -~ concentrations that both relate to the proposed uses and naturally exceed the proposed standards. Naturally occurring conditions exceeded 1 the proposed standards for trivalent chromium, copper, lead, mercury, selenium, cadmium, arsenic, zinc, nitrate, nitrite, boron, and sulfate. The proposed water quality standards for protecting aquatic life may be low since they appear to be based on an assumed alkalinity in the range of 100 to 300 mg/1 while actual maximum alkalinity concen- 1 trations have been measured 341 and 537 mg/1. The condition of the water chemistry in the Middle Fork drainage appears to be directly related to the geologic formation of the area and is not perceived as unique. i