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Order <br />2009-0009-DWQ amended by 2010-0014-DWQ & 2012-0006-DWQ <br /> 29 <br />pH is 8.5 pH units. The discharger shall take actions as described <br />below if the discharge is outside of this range of pH values. <br /> <br />2. For Risk Level 2 and 3 dischargers, the NAL storm event daily average <br />for turbidity is 250 NTU. The discharger shall take actions as <br />described below if the discharge is outside of this range of turbidity <br />values. <br /> <br />3. Whenever the results from a storm event daily average indicate that <br />the discharge is below the lower NAL for pH, exceeds the upper NAL <br />for pH, or exceeds the turbidity NAL (as listed in Table 1), the <br />discharger shall conduct a construction site and run-on evaluation to <br />determine whether pollutant source(s) associated with the site’s <br />construction activity may have caused or contributed to the NAL <br />exceedance and shall immediately implement corrective actions if they <br />are needed. <br /> <br />4. The site evaluation shall be documented in the SWPPP and <br />specifically address whether the source(s) of the pollutants causing the <br />exceedance of the NAL: <br /> <br />a. Are related to the construction activities and whether additional <br />BMPs are required to (1) meet BAT/BCT requirements; (2) reduce <br />or prevent pollutants in storm water discharges from causing <br />exceedances of receiving water objectives; and (3) determine what <br />corrective action(s) were taken or will be taken and with a <br />description of the schedule for completion. <br /> <br />AND/OR: <br /> <br />b. Are related to the run-on associated with the construction site <br />location and whether additional BMPs measures are required to (1) <br />meet BAT/BCT requirements; (2) reduce or prevent pollutants in <br />storm water discharges from causing exceedances of receiving <br />water objectives; and (3) what corrective action(s) were taken or <br />will be taken with a description of the schedule for completion. <br /> <br />C. Receiving Water Monitoring Triggers <br /> <br />1. The receiving water monitoring triggers for Risk Level 3 dischargers <br />with direct discharges to surface waters are triggered when the daily <br />average effluent pH values during any site phase when there is a high <br />risk of pH discharge12 fall outside of the range of 6.0 and 9.0 pH units, <br />or when the daily average effluent turbidity exceeds 500 NTU. <br /> <br />