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I <br /> 2014 SWMMWW MINIMUM REQUIREMENTS SUMMARY <br /> MR : MINIMUM REQUIREMENT <br /> SSP : STORMWATER SITE PLAN <br /> MR#1 PREPARATION OF STORMWATER SITE PLAN: <br /> Stormwater site plan follows 2014 Stormwater Management Manual for Western <br /> Washington. <br /> 1 MR#2 CONSTRUCTION OF STORMWATER POLLUTION PREVENTION <br /> PLAN (SWPPP): A SWPPP is provided under Section IV. <br /> MR#3 SOURCE CONTROL OF POLLUTION: Per S430 BMP's for Urban Streets: <br /> Conduct efficient street sweeping where and when appropriate to minimize the <br /> contamination of stormwater. Do not wash street debris into storm drains. Facilities not <br /> ' covered under the Industrial Stormwater General Permit may consider a minimum amount <br /> of water washing of streets. All facilities must comply with their local stormwater <br /> requirements for discharging to storm sewers. Municipal NPDES permittees 2014 <br /> ' Stormwater Management Manual for Western Washington Volume IV- Chapter 2 -Page <br /> 644 are required to limit street wash water discharges and may have special conditions or <br /> treatment requirements. <br /> ' MR#4 PRESERVATION OF NATURAL DRAINAGE SYSTEMS AND <br /> OUTFALLS: The developed site drainage will be discharged to the west of the site to <br /> follow the natural drainage course of the site. <br /> MR#5 ONSITE STORMWATER MANAGEMENT: Per Minimum Requirement#5 <br /> ' (Section 2.5.5 of the SWMMWW), the following BMP's shall be applied to the other hard <br /> surfaces: Full dispersion, Infiltration, Permeable Pavement, Bioretention, and then <br /> Dispersion. Full Dispersion is infeasible because the required native vegetation <br /> preservation could not be achieved. For infiltration, as per the Geotech report, the <br /> ' groundwater was encountered at a depth of 2'-3' and that the required vertical separation <br /> for such facilities could not be achieved. Permeable pavement and bioretention are not <br /> feasible because required vertical separation for such facilities could not be achieved. Basic <br /> Dispersion is not feasible because the required vegetated flow path could not be met. Post- <br /> Construction Soil Quality and Depth BMP T.5.13 is proposed to provide onsite stormwater <br /> management for the pervious areas of the site. <br /> Insight Engineering Co. -Stormwater Site Plan 12/20/2018 <br /> -5- <br /> I <br />