Laserfiche WebLink
The comments below were generated from this project's City of Everett Industrial Pretreatment Reviewer. All questions shall be routed through this project's <br />Public Works Reviewer Thad Newport with City of Everett Permit Services (TNewport@everettwa.gov). <br /># <br />Document <br />Sht/Pg <br />Reviewer's Comment <br />Designer's Response <br />Initials <br />This site, while originally being approved to direct stormwater to <br />the stormwater system, does not have a connection or approval <br />of plans to direct this flow to the sanitary sewer. Therefore, it is <br />considered a New Source, per EMC 14.40.030.AO, and thus must <br />comply with all requirements of EMC 14.40. <br />Additionally, the director has not authorized this facility to direct <br />all stormwater to the sanitary sewer as part of their permanent <br />solution. <br />Designer's Response: <br />The design has been revised to connect the canopy roof drain <br />line to the storm system. An asphalt berm has been added to <br />the north and east fueling pad edge to reduce the amount of <br />stormwater drainage to the sanitary sewer. These changes <br />reduce the sanitary sewer drainage area to 883 SF (reduced from <br />the 1,460 sf under existing conditions). <br />The City's sewer system includes storm drainage from thousands <br />of acres of combined sewers. According to the Everett Sewer <br />Comprehensive Plan the treatment plant processes 20 million <br />gallons per day on average. The 883 SF of new drainage is <br />insignificant compared to the average daily flow. Using rainfall <br />estimates from the City's web site the volume of runoff from the <br />883 SF is: <br />883 SF x 37.24" rainfall/year x 7.48 gal/cf X 1 ft/12" x 1 year/365 <br />days = 56.1 gal/day <br />The 56.1 gallon daily average will have no impact on the <br />20,000,000 gallons per day average being processed (0.00028% <br />of daily flow). The discharge is mitigated using existing onsite <br />oil/water separator vaults that exceed the minimum DOE fueling <br />station design recommendations by a factor of 10 for discharge <br />to the storm system and therefore more than exceeds the <br />standards for discharge to the sanitary sewer. The cost estimates <br />to replace the existing canopy with a larger canopy is in the <br />Page 5 of 7 <br />