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JACOBSONmom <br /> anNS NLTINS ENGINEERS <br /> 1. Provide Construction Stormwater BMPs as directed in 1-3.4.2 MR2: Construction <br /> Stormwater Pollution Prevention Plan (SWPPP) to prevent sediment and other pollutants <br /> from entering the wetland. <br /> Construction Stormwater BMPs will be implemented. <br /> 2. Provide Source Control BMPs as directed in 1-3.4.3 MR3: Source Control of Pollution. <br /> Refer to Volume IV and local jurisdiction requirements. <br /> There is not any source control water quality concerns with the portable classroom project <br /> and therefore no source control BMPs are being proposed. <br /> 3. Provide On-Site Stormwater Management and use LID principles as much as practicable <br /> for the site, as directed in 1-3.4.5 MR5: On-Site Stormwater Management. LID principles <br /> and practices will help meet other wetland hydroperiod protection criteria and provide <br /> additional habitat. <br /> See other areas of this report for a description of the hydroperiod protection measures. <br /> 4. Provide Runoff Treatment BMPs as directed in 1-3.4.6 MR6: Runoff Treatment to treat <br /> runoff prior to entering the wetland and its buffer. <br /> Narrative associated with MR6: Runoff Treatment is included earlier in this report. The <br /> project proposes less than 5,000 of new pollution generating surfaces and therefore is <br /> not implementing any water quality treatment systems. <br /> Wetland Hydroperiod Protection (Stormwater Management Manual for Western <br /> Washington I-C.4) <br /> A tributary area analysis has been identified for this project as matching the existing <br /> effective pervious and impervious surfaced from the current discharge to the wetland and <br /> matching the same tributary areas in the proposed condition. Therefore, it is strongly <br /> anticipated that a wetland hydroperiod analysis would show that the project is in <br /> conformance to the required standard mean/average daily total discharge volumes from <br /> the project site and mean monthly total discharge volumes to the wetland would be <br /> maintained. The criteria for monthly total discharge volumes from the site is that no more <br /> than 15% higher or lower than the pre project volumes can be discharged from the site. <br /> With equivalent existing and proposed project effective pervious and impervious surfaced <br /> being proposed for this project, no WWHM Wetland Hydroperiod Analysis was performed <br /> as it is anticipated that the hydroperiod flows and volumes would all be in compliance <br /> with this requirement. <br /> 255 S.King Street,Suite 800,Seattle,WA 98104 I 206.426.2600 I JACOBSONENGINEERS.COM <br />