IV. WATER

1. No significant changes in absorption rates or drainage patterns are anticipated as a result of the proposed facilities. The proposed project would only slightly increase the volume and velocity of runoff at the Fulton and Geysers sites. The project would include minor grading and would slightly increase the impervious surface. Approximately 130-square-foot concrete pads for two new circuit breakers and footings for new 115 kV bay structures inside the Eagle Rock Substation and two new gravel access roads would be created at the Geysers site with a combined area of 5,700 square feet. The combined area that would be disturbed at the Geysers site is 5,830 square feet, which would be less than 0.01 percent of the total area of the relatively undeveloped drainage sub-basin in which this portion of the project is located. The surface treatments proposed for the project would not significantly increase the discharge of surface water runoff generated within the drainage basin during the runoff events.

   Drainage along the 115kV power line at the Geysers site flows down a moderately steep slope. No drainage channels were observed along the alignment of the power line. However, there are swales oriented perpendicular to the slopes in which runoff is concentrated during rainstorms. The proposed project is not anticipated to alter the flow patterns within the swales. The proposed access roads would be graded to maintain existing sheet flow drainage patterns. Because the proposed project is not anticipated to alter the slope of the project, the velocity of runoff is expected to remain the same.

   No significant runoff is anticipated as a result of the proposed project at the Fulton site. A 36 square foot concrete pad is proposed for the new 115 kV circuit breaker. The construction of this pad would not result in significant changes in runoff discharge or velocity. The nominal amounts of additional surface runoff are not anticipated to affect the operation of existing Spill Prevention Containment and Countermeasures ponds at the Fulton and Eagle Rock Substations.

2. According to the FEMA Flood Insurance Rate Maps (FEMA 1991), neither project site is within a 100 year floodplain. Only minimal increases in runoff are anticipated as a result of the project, therefore no impact on flood hazards would be expected in downstream areas. No exposure of people or property to water related hazards is expected.

3. The proposed project would only involve limited grading required for the installation of the utility poles and maintenance roads. Construction related silt discharges could affect turbidity in local water courses. As a result of the implementation of the proposed erosion control and drainage mitigation measures and measures identified in Section III, Geologic Problems, no impact to surface water is anticipated.

4. The proposed project would not cross any water body; therefore, no impact would occur.

5. The closest water body to the Fulton site is Mark West Creek, located approximately 3,300 feet north of the project site. An unnamed tributary to Squaw Creek is located approximately 700 feet south of the new 115kV power line at the Geysers site. The project is not anticipated to impact these streams. The proposed project would not cause a significant change in currents or the course or direction of water movements. Discharge into surface waters or other alterations of surface water quality is not anticipated. One of the drainage swales at the Geysers site will be redirected to insure runoff to the new access road is prevented.

6. The quantity of groundwater would not be significantly changed either through direct additions or withdrawals, or through interception of an aquifer by cuts or excavations or through substantial loss of groundwater recharge capability. Any minor quantities of water needed during construction at the Fulton site would be supplied by the existing municipal water system. Water for the Geysers site would be trucked in from the Geysers Unit 11 cooling tower.

7. -h) The proposed project would not require excavations or construction of barriers that would affect the flow of groundwater. The project is not anticipated to impact the direction or rate of flow or the quality of groundwater as it involves no wells or other means of entry of contaminants into groundwater. Contaminants from substation facilities would be contained in the established Spill Prevention and Control System.

9. The proposed project is not anticipated to reduce the amount of groundwater available for public water supply. The proposed project would not use groundwater and would have no measurable effect on recharge or local groundwater use.

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