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

Drainage Report—Revision 1 Boeing Everett—Rail Spur Parking Lot September 26,2013 when sediment has filled one-third of the available storage (unless a different standard is specified by the product manufacturer). The following inlet protection measures will be applied on this project: • BMP E3.30: Storm Drain Inlet Protection 9.9 ESC Requirement#9: Underground Utility Construction The construction of underground utility lines shall be subject to the following criteria: 1. Where feasible, no more than 500 feet of trench shall be opened at one time. 2. Where consistent with safety and space considerations, excavated material shall be placed on the uphill side of trenches. 3. Trench dewatering devices shall discharge into a sediment trap or sediment pond. 9.10 ESC Requirement#10: Construction Access Routes Construction vehicle access will be limited to one entry inside the Boeing security fence on the east side of the site. If sediment is tracked offsite, roads/accesses shall be cleaned thoroughly at the end of each day, or more frequently during wet weather, if necessary to prevent sediment from entering drainage inlets. Sediment shall be removed from roads by shoveling or pickup sweeping and shall be transported to a controlled sediment disposal area. Street washing will be allowed only after sediment is removed in this manner. Street wash wastewater shall be controlled by pumping back on site to an approved infiltration facility. BMPs relevant to establishment of construction access for this project may include: • BMP E2.10: Stabilized Construction Entrance and Tire Wash • BMP E2.15: Construction Road Stabilization 9.11 ESC Requirement#11: Removal of Temporary BMPs All temporary erosion and sediment control BMPs shall be removed within 30 days after final site stabilization is achieved or after the temporary BMPs are no longer needed. Trapped sediment shall be removed or stabilized onsite. Disturbed soil areas resulting from removal shall be permanently stabilized. 9.12 ESC Requirement#12: Dewatering Construction Sites If dewatering devices are required,they shall discharge into a sediment trap or sediment pond. 9.13 ESC Requirement #13: Control of Pollutants other than Sediment on Construction Sites All pollutants other than sediment that occur onsite during construction shall be handled and disposed of in a manner that does not cause contamination of stormwater. 9.14 ESC Requirement#14: Maintenance All temporary and permanent erosion and sediment control BMPs shall be maintained and repaired as needed to assure continued performance of their intended function. All maintenance and repair shall be conducted in accordance with an approved manual. DCG, Inc. Page 10 of 11