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operations there is the potential that surface water generated from the project site could be degraded. Comment DI-F The submitted comment requests that the DEIR identify the hydrologic conditions on the project site. The following discussion is from Page 24 and 25 of the DETR, discussing the hydrologic condition on the project site. The project site is relatively flat. Prior to the demolition of the project site, the majority of the site was covered by an asphalt parking lot. Approximately 60% of the project site drained in a north to south direction, by sheet flow along Farmers Drive, before entering an existing storm drain, at the corner of Memory Lane and Flower Street. The existing storm drain is tributary to Santiago Creek just upstream ofthe Santa Ana River. The 25- year discharge at the limit of the property was approximately 14.33 cfs. The 100-year peak discharge was approximately 18.68 cfs. The remaining 40% of the project site drained in a south to north direction onto Orange Road. The 25-year discharge was 8.15 cfs and the 100-year discharge is 10.68 cfs. The proposed project would maintain the existing flow paths, and would not alter existing drainage areas tributary to the Santiago Creek or the Santa Ana River. Implementation of the proposed project would result in a reduction of peak discharges during the 25- Year and 1 00- Year events compared to the previous condition on the project site. Along Farmers Drive the 25-Year discharge would be approximately 13.43 cfs and the 100- Y ear discharge would be approximately 17 .61 cfs. Along Orange Road the 25- Year discharge would be approximately 6.11 cfs and the 100-Year discharge would be approximately 8.09. The reduction in discharge would be due primarily to the increase of pervious surfaces provided on the project site. With this condition, there would be a 6% reduction of peak flows discharged to Farmers Drive and a 25% reduction of peak flows to the intersection of Flower Street and Orange Road. Comment DI-G The submitted comment requests that the DEIR provide an assessment of the significance of water quality impacts associated with the proposed project. Page 23 of the DEIR identifies the water quality impacts as potentially significant and that to reduce potential short-term construction related water quality impacts and long- term operational water quality impacts to a level that would be less than significant, Mitigation Measures WQ- 1, WQ-2 and WQ-3 shall be implemented. Comment DI-H The submitted comment requests an evaluation of threshold of significance to determine potential water quality impacts. 75Co,47