3003 W CASINO RD BLDG 40-YD 2019-11-27

Drainage Report—Revision 1 Boeing Everett—Rail Spur Parking Lot September 26,2013 Road. Runoff from the south subbasin will enter an existing catch basin south of the proposed pavement before conveyance to a StormFilter Catch Basin in the southern portion of the new pavement area. From the StormFilter Catch Basin, this runoff will tie into an existing catch basin west of the proposed pavement area and discharge in Japanese Gulch. See the Stormwater Plans in APPENDIX D for detailed drawings of the stormwater system. 6. SPECIAL REPORTS AND STUDIES No special reports or studies were done as part of this project. 7. BASIN AND COMMUNITY PLANNING AREAS No basin or community planning areas are associated with the development of the site that would require additional requirements beyond those stipulated in the Stormwater Manual. 8. OTHER PERMITS A Washington State Department of Ecology Construction Stormwater Permit will be required for the project and has been prepared and will be submitted by others under separate cover.No other permits beyond the Clearing and Grading Permit will be required by the City of Everett. 9. EROSION AND SEDIMENT CONTROL PLAN The ESC Plan was prepared in accordance with the Stormwater Manual. ESC measures were designed for the project and are shown on the TESC plan in APPENDIX C. 9.1 ESC Requirement#1: Stabilization and Sediment Trapping All exposed soils shall be stabilized from erosion, protected with sediment trapping measures, and when possible, be located away from storm drain inlets, waterways, and drainage channels. From October 1 to April 30, no soils shall remain unstabilized for more than 2 days. From May 1 to September 30, no soils shall remain unstabilized for more than 7 days. Prior to leaving the site, stormwater runoff shall pass through an appropriate sediment removal BMP. Stabilization and sediment trapping BMPs applicable to this project include: • BMP E1.20: Clean Plastic Covering • BMP E2.20: Dust Control • BMP E3.10: Filter Fence • BMP E3.15: Straw Bale Barrier 9.2 ESC Requirement#2: Delineate Clearing and Easement Limits In the field, clearing limits and easements, setbacks, sensitive/critical areas and their buffers, trees, and drainage courses will be marked. The BMPs relevant to marking the clearing limits that will be applied for this project may include: • BMP C103: High Visibility Plastic Fence DCG, Inc. Page 8 of 11