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Home My WebLink AboutNCS000331_11_Fort Bragg Monitoring Plan_20210517Monitoring Plan extracted from SWMP Section 7.10. 7.10 Stormwater Quality Monitoring Requirements According to Part II, Section J of Permit No. NCS000331, the following is required to meet the requirements of the Monitoring Requirements. Fort Bragg's NDPES permit requires water quality monitoring, both analytical and visual, at outfalls that receive stormwater runoff from a regulated industrial activity. All regulated industrial activities at Fort Bragg are documented in the SWPPP. 7.10.1 Objectives The objective of this NPDES permit requirement is to assess the effectiveness of Fort Bragg's stormwater program and to prioritize areas of the program that may require additional resources. Water quality monitoring results can also be used to modify the program components, as necessary, to accomplish the objectives of the program. 7.10.2 Compliance Fort Bragg shall conduct analytical and visual monitoring as required by the NPDES permit. Fort Bragg shall submit required monitoring reports to NCDEQ DEMLR and retain records of its monitoring efforts and results for review by NCDEQ DEMLR. The following sections summarize Fort Bragg's stormwater monitoring requirements. 7.10.2.1 Analytical Monitoring The specific analytical monitoring activities mandated by the NPDES Permit NCS000331 for Fort Bragg (Appendix 1). These are required as part of the monitoring process in accordance with the provisions outlined in the SWPPP. Data for the sampling locations are kept in the WMS office and stored in the Fort Bragg Stormwater Management Database. The following list of parameters shall be monitored during a storm event, for Vehicle maintenance areas, designated in the SPPP as Area A (Outfall 53 to McPherson Creek), Area C (Outfall 39 to an unnamed tributary to Stewarts Creek), Area D (Outfall 84 to Big Branch), Area E (Outfall 71 to Beaver Creek), and Area F (Combined Outfalls 20, 21, and 76 to an unnamed tributary to Little Cross Creek). Parameter Units Measurement Frequency Sample Type Total Suspended Solids JSS) mg/l Once per year Grab Oil and Grease mg/l Once per year Grab pH Standard Units Once per year Grab Total Flow MG Once per year Event Duration Minutes Once per year Total Rainfall inches Once per year The following list of parameters shall be monitored during a storm event, for material handling areas, designated in the SPPP as site 4-2 (outfall to Tank Creek), site 8-2 (outfall 93 to an unnamed tributary to Beaver Creek), and site 8-3 (combined outfalls 18 and 19 to an unnamed tributary to Beaver Creek). Parameter Units Measurement Frequency Sample Type Total Suspended Solids (TSS) mg/l Once per year Grab Oil and Grease mg/l Once per year Grab pH Standard Units Once per year Grab Total Flow MG Once per year Event Duration Minutes Once per year Total Rainfall inches Once per year The following list of parameters shall be monitored during a storm event, for fueling areas, designated in the SPPP as site 3-14 (outfall 61). Parameter Units Measurement Frequency Sample Type Oil and Grease mg/l Once per year Grab Total Flow MG Once per year Event Duration Minutes Once per year Total Rainfall inches Once per year The following list of parameters shall be monitored during a storm event, for the airfield, designated in the SPPP as site 8-4 (outfall 22 to Cross Creek). Parameter Units Measurement Frequency Sample Type Total Suspended Solids (TSS) mg/l Once per year Grab Oil and Grease mg/l Once per year Grab pH Standard Units Once per year Grab Total Flow MG Once per year Event Duration Minutes Once per year Total Rainfall inches Once per year Ambient Monitoring. The following list of parameters shall be monitored at two points, a point north of Texas Pond and Simmons Airport and the other at Flat Creek near Inverness. Parameter Units Measurement Frequency Sample Type Total Suspended Solids (TSS) mg/1 Once per year Grab Oil and Grease mg/1 Once per year Grab pH Standard Units Once per year Grab Analytical Monitoring Schedule. Monitoring Period Start End Year 1 April 1, 2016 March 31, 2017 Year 2 April 1, 2017 March 31, 2018 Year 3 April 1, 2018 March 31, 2019 Year 4 April 1, 2019 March 31, 2020 Year 5 April 1, 2020 March 31, 2021 Cutoff Concentrations. For each parameter, the arithmetic mean of all analytical sampling results collected during the term of the permit shall be calculated for each individual outfall and compared to the cut-off concentrations listed below. At a minimum, Fort Bragg must perform analytical sampling during the first year of the permit. If the analytical results fall at or below the cutoff concentrations listed below, Fort Bragg is not required to sample that parameter at that outfall for the remainder of the permit. If analytical results exceed the cutoff concentration, subsequent sampling is required annually. Each year, Fort Bragg has the option to assess if the arithmetic mean of data collected for each parameter at each outfall is below the cutoff concentration. If the arithmetic mean is less than the cutoff concentration then Fort Bragg is not required to continue analytical monitoring for that parameter at that outfall during the remainder of the term of the permit unless a significant change in the operations in the drainage area occurs. Parameter Cut-off Concentration Oil and Grease 30 mg/1 pH (do not take average, use most recent pH sample result) 6-9 standard units TSS 100 mg/1 7.10.2.2 Qualitative Monitoring Qualitative monitoring is a visual inspection of each storm water discharge outfall (SDO) associated with industrial activities and/or oil water separators regardless of representative outfall status. No analytical tests are required. Qualitative monitoring of stormwater outfalls does not need to be performed during a representative storm event. Visual observations will be performed twice per year, once in the spring (April —June) and once in the fall (September— November), at each SDO identified in the SWPPP. Outfalls where analytical monitoring is performed are not exempt from visual monitoring requirements. Discharge characteristics that should be visually monitored at each industrial SDO are: • Color • Odor • Clarity • Floating solids • Suspended solids • Foam • Oil sheen • Other pollution indicators. The results of Qualitative Monitoring will be recorded on a Stormwater Discharge Outfall Qualitative Monitoring Report. These inspections are documented on an inspection form and kept in the WMS office and stored in the Fort Bragg Stormwater Management Database. The results of these inspections are discussed and summarized in the annual report submitted to NCDEQ.