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• 2. As an alternative to the 25 NTUs effluent limit noted in Table 5 below (applied at <br />the point where stormwater [or authorized non-stormwater] is discharged off -site), <br />Permittees may choose to comply with the surface water quality standard for <br />turbidity. The standard is: no more than 5 NTUs over background turbidity when <br />the background turbidity is 50 NTUs or less, or no more than a 10% increase in <br />turbidity when the background turbidity is more than 50 NTUs. In order to use the <br />water quality standard requirement, the sampling must take place at the following <br />locations: <br />• <br />• <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 <br />the area of influence of the discharge. <br />Discharges that exceed the numeric effluent limit for turbidity constitute a <br />violation of this permit. <br />4. Permittees whose discharges exceed the numeric effluent limit shall sample <br />discharges daily until the violation is corrected and comply with the non- <br />compliance notification requirements in Special Condition S5.F. <br />Table 5: Turbidity, Fine Sediment & Phosphorus Sampling and Limits for 303(d)-Listed Waters <br />Parameter identified <br />in 303(d) listing <br />Parameter <br />Sampled <br />Unit <br />Analytical <br />Method <br />Sampling <br />Frequency <br />Numeric Effluent <br />Limit' <br />• Turbidity <br />Turbidity <br />NTU <br />SM2130 <br />Weekly, if <br />25 NTUs, at the <br />• Fine Sediment <br />discharging <br />point where <br />• Phosphorus <br />stormwater is <br />discharged from the <br />site; OR <br />In compliance with <br />the surface water <br />quality standard for <br />turbidity (S8.C.2.a) <br />' Permittees subject to a numeric effluent limit for turbidity may, at their discretion, choose either numeric effluent <br />limitation based on site -specific considerations including, but not limited to, safety, access and convenience. <br />D. Discharges to Water Bodies on the 303(d) List for High pH <br />Permittees who discharge to segments of water bodies on the 303(d) list (Category <br />5) for high pH must conduct pH sampling in accordance with the table below, and <br />comply with the numeric effluent limit of pH 6.5 to 8.5 su (Table 6). <br />Con,struction Slorwivater General Permit <br />Page 25 <br />