STATE OF CALIFORNIA, PETE WILSON,
Governor
December 17, 1997
RE: Variance Request #39 - Allow for the use of water trucks to remove dirt from surface streets to help in complying with Mitigation Measure A-8; this measure requires that streets be swept manually or with a water sweeper at the end of the day if visible soil material is carried onto adjacent public paved roads.
Dear Mr. Shauers:
We have reviewed the above-referenced variance request and approve your request based on the following factors:
• PPSI and its contractors propose to use the following procedures when using water trucks to reduce dirt on roadways:
1. In areas with large amounts of dirt, front end loaders will scrape off surface dirt;
2. Water sweepers will be used to remove remaining dirt;
3. If excessive dirt is still a problem (e.g., after implementation of steps 1 and 2), a water truck will be used to clean the remaining dirt from the streets. Sediment traps and all other devices required to comply with Storm Water Discharge Permits will be used. All sediment catchment devices will be regularly checked and cleaned to allow maximum performance.
• As proposed, the water method would reduce emissions associated with the following: 1) Repeated use of a mechanical sweeper and 2) particulates from potential residual dust remaining on the streets.
• Use of water to wash streets, either beyond the use of sweepers, or instead of sweepers, would result in an increased use of water on the project. However, this increased water use would be mitigated with the use of reclaimed water for street cleaning purposes, as required below.
• Use of water trucks to clean streets could result in run off leaving the ROW that contains sediments. Implementation of the requirements of the Storm Water Pollution Prevention Plan (SWPPP) and Storm Water Discharge Permits would mitigate this potential impact.
• The following measures shall be implemented:
- Reclaimed water shall be used by all water trucks and sweepers used for street cleaning purposes.
- Water sweepers shall be used for any mechanical street sweeping operations.
- SWPPP and Storm Water Discharge Permit requirements shall be implemented to ensure that run off leaving the right-of-way as a result of street cleaning does not contain sediments.
- Implementation of this variance in accordance with the provisions noted above shall be verified on a random basis by a CPUC/ANF Environmental Monitor.
Sincerely,
