7000 HARDESON RD 2018-01-02 MF Import

10. An NPDES (National Pollutant Discharge Elimination System) permit, administered by Washington State's Department of Ecology, will be required for clearing and grading activities on this site if the site area disturbed by land alteration activities is greater than or equal to 5 acres. 11. If the future use of the site will result in the potential for accidental spills of chemicals, including oils or fuels, to the city's sanitary sewer, an Accidental Spill Prevention Plan will need to be prepared per the direction of the city of Everett's Industrial Pretreatment Program. 12. All chemicals or products of a hazardous or toxic nature that may be used or stored on the site must be stored under cover and isolated from the storm drainage s},stem. 13. Any work within the stream's high water mark will require a Hydraulic Projects Approval from the state Department of Fish and Wildlife. 14. , Fueling facilities shall be designed and installed in accordance with City standards. 15. No hydraulic connection between the bus wash or chassis wash and the storm drainage system shall be allowed. 16. Special Comments Regarding the Proposed Stormwater Treatment Facilities a. The applicant for this project is proposing to provide a Compost Stormwater Filter for treatment of stormwater runoff from this site. The Compost Stormwater Filter is considered an experimental stormwater best management practice which has not yet seen extensive field use, but which shows promise for stormwater treatment if properly designed and maintained. b. Some difficulties have been encountered with compost stormwater filters installed in this region, including serious clogging problems encountered with the filter, which causes storm flow to bypass the treatment media and discharge directly (untreated) to the receiving water. c. If utilized on this site, the City would require a monitoring, maintenance, and contingency plan to be developed for the compost stormwater filter. The plan would need to be developed by the applicant and approved by the City prior to issuance of building permits. The goal of monitoring would be to determine that the filter was achieving pollutant removals, for the stormwater treatment design storm, comparable to those which would be achieved if a stormwater facility meeting City standards had been provided. Given the fill nature of the soils on this site, a wetpond would be required, Per City standards, to treat stormwater runoff. In addition, the monitoring portion of the plan would be required to propose measurements to demonstrate that the hydraulic capacity of the filter remained adequate to consistently treat, and not bypass, the peak flow from the stormwater treatment design storm. d. The maintenance portion of the plan would set forth the maintenance standards for the filter, including methods and frequency of filter renewal and compost replacement. Initially, the frequency of renewal or compost replacement necessary would be based on a reduction of hydraulic capacity over time due to sediment buildup or other factors, as determined by monitoring.