Laserfiche WebLink
Page 1 of 4 <br />Garrett T. Backus [EH] <br />From: Evan Edgar levan@edgarinc.org] <br />Sent: Sunday, September 24, 2006 4:57 PM <br />To: Garrett T. Backus [EH] <br />Cc: 'Scott Stortroen' <br />Subject: RE: Tracy Transfer RFI amendment <br />Garrett: <br />When EBA did the calculation in early 1990's — the state of the art for composting facilities' drainage design <br />mimicked landfills. EBA got into 100 -year 24-hour design and water balance — as what was used during that era. <br />Into the mid-1990 to the early 2000's- many of the Water Boards have a waste discharge requirement (WDRs) <br />waiver process in place where a 24-hour 25 -year stream was the standard without water balance considerations. <br />The Central Valley RWQCB is now proposing a 24-hour, 100 -year design standard without water balance. <br />With respect to the Tracy Compost pad, we submitted the information copied below: <br />True —the pad is now 150,000 square feet and increase from 90,000 square feet, where the pond can handle the <br />increase in pad size. <br />My calculations do not include the evaporation aspects from previous design standard. Either way though it has <br />capacity. <br />As a Contingency Plan, the operator is committee to pump the pond should the capacity be exceeded. <br />Please phone if you have any questions. <br />Evan <br />DRAINAGE REVIEW: <br />Figure 3 — Preliminary Site Plan (1993) has been amended to show the Site Plan <br />modifications to the yard waste composting area and the wood waste processing area. As part <br />of the Site Plan modifications and actual expansion, the LEA requested a Drainage Review to <br />ensure that the drainage facilities have adequate capacity. <br />Figure 3 was originally presented an operations plan of 200 feet by 300 feet, 60,000 square <br />feet, and east of the MRF/Transfer Station with the following activity: <br />• Wood storage & Yard Waste Composting Area <br />• Final cure area <br />• Screening area <br />Unloading and grinding area <br />Figure 3 also shows a "Future Wood Storage & Composting "Area adjacent to the operations <br />area listed above. This area is 300 feet by 550 feet, or about 165,000 square feet. <br />1993 RFI Calculations: <br />Reviewing Appendix E of the RFI, the drainage system to capture on-site rainfall was designed <br />to accommodate twice the volume of run-off generated from the 10-year/24-hour precipitation <br />9/25/2006 <br />