1300 W MARINE VIEW DR 2018-01-02 MF Import

Page 26 of 46 b. Inlet protection deviccs shall be cleaned or removed and replaced when sediment has filled one-third of the available storage (unless a different standard is specified by the product manufacturer). 8. Stabilize Channels and Outlets a. All temporary on-site conveyance channels shall be designed, conswcted, and stabilized to prevent erosion from the following expected peak flows: i. West of the Cascade Mountains Crest: Channels shall handle the peak 10 minute velocity of flow from a Type lA, 10-year, 24-hour frequency storm for the developed condition. Altematively, the 10-year, 1-hour flow rate indicated by an approved continuous runofl model, increased by a factor of 1.6, may be used. The hydrologic analysis shall use the existing land cover condition for predicting flow rates from tributary areas outside the project limits. For tributary areas on the project site, the analysis shall use the temporary or permanent project land cover condition, whichever will produce the highest flow rates. If using the WWHM to predict flows, bare soil areas should be modcicd as "landscaped area." ii. East of the Cascade Mountains Crest: Channels shall handle the expected peak flow velociry from a 6-month, 3-hour storm for the developed condition, rcferred to as the short duration storm. b. Stabilicotia�, including armoring material, adequate to prevent erosion of outlets, adjacent stream banks, slopes, and downsveam reaches shall be provided at the oudets of all com�cyance systems. 9. Control Pollutants a. All pollutants, including waste matcrials and demolition debris, that occur onsite shall be handled and disposed ot in a manner that does not cause contamination of stortnwatcr. b. Cover, containment, and protection from vandalism shall be provided for all chcmicals, liquid products, petroleum products, and other materials that have the potential to pose a tiveat to human health or the environment. On-site fueling tanks shall include secondary containment. c. Maintenance, fueling, and repair of heavy equipment and vehicles shall be conducted using spill prevention and control measures. Contaminated surfaces shall be cleaned immediately following any spill incident d. Whecl wash or tire bath wastewater shall be discharged to a separate omsite treamient system or to the sanitary sewer with local sewer district approval. e. Application of fertilizers and pesticides, shall be conducted in a manner and at applicatiol rates diat will not result in loss of chemical to stormwater runoff. Manufacturers' label requirements fer application rates and procedures shall be followcd.