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1. Prevents exposing stormwater to pollutants for which the waterbody is impaired, and <br /> retains documentation in the SWPPP that details procedures taken to prevent exposure <br /> on site; or <br /> 2. Documents that the pollutants for which the waterbody is impaired are not present at <br /> the site, and retains documentation of this finding within the SWPPP; or <br /> 3. Provides Ecology with data indicating the discharge is not expected to cause or <br /> contribute to an exceedance of a water quality standard, and retains such data on site <br /> with the SWPPP.The operator must provide data and other technical information to <br /> Ecology that sufficiently demonstrate: <br /> a. For discharges to waters without an EPA-approved or-established TMDL,that the <br /> discharge of the pollutant for which the water is impaired will meet in-stream water <br /> quality criteria at the point of discharge to the waterbody; or <br /> b. For discharges to waters with an EPA-approved or-established TMDL,that there is <br /> sufficient remaining wasteload allocation in the TMDL to allow construction <br /> stormwater discharge and that existing dischargers to the waterbody are subject to <br /> compliance schedules designed to bring the waterbody into attainment with water <br /> quality standards. <br /> Operators of construction sites are eligible for coverage under this permit only after <br /> Ecology makes an affirmative determination that the discharge will not cause or <br /> contribute to the existing impairment or exceed the TMDL. <br /> C. Sampling and Numeric Effluent Limits for Discharges to Water Bodies on the 303(d) List <br /> for Turbidity, Fine Sediment, or Phosphorus <br /> 1. Permittees who discharge to segments of water bodies on the 303(d) list(Category 5)for <br /> turbidity, fine sediment, or phosphorus must conduct turbidity sampling in accordance <br /> with Special Condition S4.C.2 and comply with either of the numeric effluent limits noted <br /> in Table 5 below. <br /> 2. As an alternative to the 25 NTUs effluent limit noted in Table 5 below (applied at the <br /> point where stormwater [or authorized non-stormwater] is discharged off-site), <br /> Permittees may choose to comply with the surface water quality standard for turbidity. <br /> The standard is: no more than 5 NTUs over background turbidity when the background <br /> turbidity is 50 NTUs or less, or no more than a 10% increase in turbidity when the <br /> background turbidity is more than 50 NTUs. In order to use the water quality standard <br /> requirement,the sampling must take place at the following locations: <br /> a. Background turbidity in the 303(d)-listed receiving water immediately upstream <br /> (upgradient) or outside the area of influence of the discharge. <br /> b. Turbidity at the point of discharge into the 303(d)-listed receiving water, inside the <br /> area of influence of the discharge. <br /> 3. Discharges that exceed the numeric effluent limit for turbidity constitute a violation of <br /> this permit. <br /> 4. Permittees whose discharges exceed the numeric effluent limit must sample discharges <br /> daily until the violation is corrected and comply with the non-compliance notification <br /> requirements in Special Condition SS.F. <br /> Construction Stormwater General Permit Page 21 <br />