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Design Requirements <br /> 123. NPDES Permit design requirements include, but are not limited to, the following: <br /> a. Source control, site design, implementation, and maintenance standards <br /> when a regulated project (such as a commercial, industrial, residential <br /> subdivision, mixed use, or public project) creates and/or replaces 10,000 <br /> square feet or more of impervious surface (5,000 square feet for auto service <br /> facilities, retail gasoline outlets, restaurants, and uncovered parking lots), <br /> including roof area, street, and sidewalk. <br /> b. Hydromodification standards when a regulated project creates and/or <br /> replaces a total impervious area of one acre or more. <br /> c. Compliance with a Diazinon pollutant reduction plan (Pesticide Plan) to <br /> reduce or substitute pesticide use with less toxic alternatives. <br /> d. Compliance with a Copper Pollutant Reduction Plan and a Mercury Pollutant <br /> Reduction Plan. <br /> 124. The following requirements shall be incorporated into the project: <br /> a. The project developer shall submit a final grading and drainage plan prepared <br /> by a licensed civil engineer depicting all final grades and onsite drainage <br /> control measures including bio-retention swales. Irrigated bio-retention <br /> swales shall be designed to maximize stormwater entry at their most <br /> upstream point. The grading and drainage plans shall be subject to the <br /> review and approval of the City Engineer prior to the issuance of a grading or <br /> building permit, whichever is sooner. <br /> b. In addition to natural controls, the project developer may be required to install <br /> a structural control(s), such as an oil/water separator(s), sand filter(s), or <br /> approved equal(s) in the parking lot and/or on the site to intercept and pre- <br /> treat stormwater prior to reaching the storm drain. The design, location(s), <br /> and a schedule for maintaining the separator shall be submitted to the City <br /> Engineer/Chief Building Official for review and approval prior to the issuance <br /> of a grading or building permit, whichever is sooner. The structural control <br /> shall be cleaned at least twice a year (once immediately prior to October 15 <br /> and once in January). <br /> c. The project developer shall submit to the City Engineer the sizing design <br /> criteria and calculations for a hydromodification facility, if required, and for the <br /> treatment of stormwater runoff. The design criteria and calculations shall be <br /> subject to the review and approval of the City Engineer and shall be <br /> submitted prior to the issuance of a grading or building permit, whichever is <br /> sooner. <br /> 22 of 28 <br />