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HomeMy WebLinkAboutCape Fear Steam Station (14)t . NCDEN North Carolina Department of Environment and Natural Resources Division of Water Quality Beverly Eaves Perdue Coleen H Sullins Dee Freeman Governor Director Secretary STAFF REVIEW AND EVALUATION NPDES Stormwater Permit Facility Name NPDES Permit Number - Facility Location: Type of Activity. SIC Code (if applicable)• Receiving Streams River Basin Stream Classification - Proposed Permit Requirements Monitoring Data Progress Energy Carolinas, Inc - Cape Fear Steam Electric Plant NCS000550 500 CP&L Road, Moncure, NC (Chatham County) Steam Electric Generation 4911 See Figure 1 ( EI Cape Fear River Basin, Sub -basin 03-06-07 � EEC ; WS -Iv JUN 2 9 2011 See attached draft permit u - G�� r� rc`tn, See Table 1 Response Requested by (Date). July 25, 2011 Central Office Staff Contact: Return to: B Special Issues: ias, (919) 807-6372 Issue a �om e a ; a Rating Scale:=1(easy)�to mm X10 aliaird �.� Compliance history 5 Benchmark exceedance 5 Location (TMDL, T&E species, etc 3 Other Challenges- • Power Plant - New SW Permit 8 Difficulty Rating: 21/40 SEPU 2 3 2011 DENR. WATER QUALITY "MIDSANDSTo"WA"E BRANCH Special Issues Explanation• • Previously this facility only had an NPDES WW permit for its discharges (NC0003433) Description of Onsite Activities: The Cape Fear Steam Electric Plant is a coal-fired electric generation plant The station includes two coal- fired heat recovery boilers and four combined cycle combustion turbines The site has four stormwater outfalls: SW -1 (inactive ash pond, rarely discharges), SW -2 (railroad track between plant entrance road and plant site, to Shaddox Crk), SW -3 (roadside beside plant entrance, to Shaddox Crk), and SW -8 (inactive ash pond, rarely discharges) Pagel of 8 NCS000550 t Documents Reviewed: • NPDES Stormwater Permit Application Materials (EPA Forms 1 & 2F)* *Note SPU's add info letter said a larger -scale site map was preferable to the 85"x 11"aerial map, but the response letterjust included a narrative response and two aerial maps with more detail instead • National Heritage Program (NHP) Threatened and Endangered Species Database • SPU and NPDES Wastewater Permit Files • Central Files • 303(d) List (2010 Assessment) • 2005 Catawba Basmw!de Plan and consultation with Basmwide Planning Staff History: Until now, the Cape Fear Steam Plant has had only a wastewater permit and sampled some stormwater outfalls for the NPDES WW renewal application. The Division initiated an effort this past year to segregate stormwater management requirements into a separate NPDES SW permit, rather than combine WW and SW under one NPDES permit, for power plants. The decision for that strategy is based on the accumulating complexities in power plant wastewater permits, and our need to better manage stormwater data records for these sites The attached permit was drafted to reflect the permitting strategy for all coal-fired power plants set by the Stormwater Permitting Unit (SPU) in 2009 Figure 1: Map of Facility Page 2 of 8 C 5 NCS000550 Central Office Review Summary: 1. Owner's Other Permits • NPDES Wastewater Permit NC0003433 Air Permit 01057T28 [Not noted on EPA Form 1] Others? 2 General Observations - In 2009 the SPU established a strategy for all coal-fired power plant stormwater permits The approach includes a standard suite of parameters for analytical monitoring (see attached discussion) Since then, at least four power plants have been monitoring stormwater discharges for those parameters Elizabethtown Power LLC (NCS000352), Lumberton Power LLC (NCS000349), Progress Energy's Mayo Steam Electric Power Plant (NPDES WW + SW NC0038377), and Progress Energy's Weatherspoon Steam Electric Plan (NPDES WW + SW NC0005363). Data from those facilities in Central Files (12 samples total) show Zn and Cu benchmarks exceeded most often Those sites also have mercury levels in stormwater discharges that range up to 10 ng/1 Earlier mercury data from Weatherspoon showed higher levels Mercury levels in both sampled outfalls at the Cape Fear Steam Plantfor this application ranged 2 4-55 ng/1 This plant site was included in the Environmental Integrity Project and Earthjustice report called "Out of Control. Mounting Damages From Coal Ash Waste Sites" (February 2010), attached The report noted groundwater monitoring at the Cape Fear Steam Plant found concentrations of lead, chromium, boron, iron, manganese, and sulfate above NC groundwater standards, at wells within 125' of ash pond impoundments. The plant site operates four unlined ash impoundments, one active and three inactive. The draft stormwater permit proposes monitoring for all of these constituents except iron and manganese According to Progress Energy contact discussions with NPDES wastewater staff, this facility is scheduled to be decommissioned in 2017 3. Impairments and Basinwide Planning Recommendations- The segment of the Cape Fear River downstream of where this facility discharges stormwater is impaired for chlorophyll a, indicative of excessive nutrient loading in this river system (both nitrogen and phosphorus) The segment begins just above Buckhorn Dam [AU #18-(4.5)]. The last current Basinwide Plan (2005) mentions nutrient -laden runoff from urban and agricultural land uses as a contributor The Middle Cape Fear River Basin Association (MCFRB) continues to monitor water quality in this segment, this Progress Energy facility is a member of the MCFRB. Excessive nutrient loading continues to be a concern for the Cape Fear River system. Basinwide Planning Staff (N Deamer, 6/21/2011) advised of the need for reducing nutrients to this segment of the river At some point in the future, a TMDL or nutrient management strategy will be needed from below Jordan Lake Dam and Randleman Reservoir to the Buckhorn Dam Sampling results from two of the stormwater outfalls submitted with the application (SW -002 and SW - 003) indicate nutrient levels are relatively low (TN = 1.62 mg/l, 199 mg/l, TP = 0.17 mg/1, 0 69 mg/1) Because of the need to better characterize sources in this area, the draft permit proposes nutrient monitoring for this permit term. The reviewer recommends removing TN and TP monitoring at the next renewal if results confirm there is minimal concern. 4. Threatened and Endangered. None identified in the vicinity of this site (NHP Virtual Workroom, accessed 6/23/2011) 5. Location: No issues with locating this facility. 6 Industrial Changes Since Previous Permit. N/A, new stormwater permit. Page 3 of 8 NCS000550 7 Analytical Monitoring Notes Two outfalls were sampled as part of the NPDES stormwater application These outfalls (SW -002 and SW -003) were sampled in September 2010 for the NPDES wastewater permit renewal application (submitted May 2011) The other outfalls (SW -001 and SW -008) discharge stormwater from ash ponds that have been inactive for 35 years, and discharge is rare See application documents (Form 2F) SW -002 [Drains area along railroad between entrance road and plant site, as well as open field, to Shaddox Creek] • COD levels were under the 120 mg/1 benchmark (48.6 mg/1), and BOD levels were low (3 6 mg/1), suggesting a larger amount of non-biodegradeable organic material TSS, 0&G, pH and nutrients were all well below or within range of current stormwater benchmarks The copper concentration (0 007 mg/1) was the same as the current benchmark Arsenic, mercury, selenium, chromium, and nickel concentrations levels were all below benchmarks No results were reported for aluminum, antimony, beryllium, boron, bromide, cadmium, lead, magnesium, manganese, molybdenum, silver, thallium, tin and zinc, but all were reported as pollutants "that may be present in coal along the rail " Total residual chlorine (TRC), ammonia, nitrate -nitrite, TKN, and fecal coliform were also reported ("natural environmental processes" were cited as a potential source), but these would not likely be associated with industrial activities at this plant site Although fecal values were noted over the 1000 CPU/100 ml benchmark, monitoring is not recommended SW -003 [Drains plant entrance roadside swale] COD (67 mg/1) and BOD (9.3 mg/1) were slightly higher than the other outfall but still below benchmarks (120 mg/1, 30 mg/l, respectively) TSS (35 2 mg/1) was higher but also below the 100 mg/l benchmark TN and TP were similar to SW -002 levels. All metals measured (see above) were below benchmarks Again, no results were reported for aluminum, antimony, beryllium, boron, bromide, cadmium, lead, magnesium, manganese, molybdenum, silver, thallium, tin and zinc, but all were reported as pollutants "that may be present in coal along the rail " Likewise TRC, ammonia, nitrate -nitrite, TKN, and fecal coliform were reported but not likely attributable to industrial activities Although fecal values were noted over the 1000 CPU/100 ml benchmark, monitoring is not recommended 8 Qualitative Monitoring Notes- N/A, new permit. Page 4 of 8 t Permit Recommendations: Analytical Monitoring: Proposed analytical monitoring is consistent with the Stormwater Permitting Unit's strategy for all power plant permits established in 2009. For more information, see attached discussion. The draft includes a Semi-annual monitoring for 13 priority metals (Ag, As, Be, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Se, Tl, Zn) + Al & B, with benchmarks where available b Semi-annual mercury (Hg) monitoring with more sensitive method 1631E but no benchmark (or obligation to monitor monthly in Tier 2). c Semi-annual monitoring for COD, TSS, pH, sulfates, and 0&G d Requirement to submit annual data summary to DWQ regional office 2. In addition, the draft permit proposes nutrient monitoring for this permit term because of the chlorophyll a standard violations lust downstream in the Cape Fear River (should be removed at renewal if there is no concern) 3 Coal pile runoff discharge (subject to stormwater effluent guidelines limitations) is covered under the plant's wastewater permit (NC0003433); coal yard runoff is directed through the West Ash Pond to NPDES WW outfall 007(UT to Cape Fear River). 4 During the warmer months of the year when cooling towers are used, stormwater contributes a very small percentage of flow compared to the much larger, continuous cooling water and other wastewater flows (0 18 MGD of a total of over 250 MGD, or 0.07%, based on flows reported in Form 2C Part II.). In cooler months when the towers are not used, stormwater flow percentage drops to 0 9% (or 0 3% if the estimate is based on once -through cooling flows of 58 8 MGD reported in the NPDES WW permit fact sheet, rather than Form 2C). In either case, the potential for stormwater contaminants to reach concentrations of concern is extremely small throughout the year In addition, the draft NPDES WW permit includes monitoring for Cr, As, Se, Hg (low level method 1631), Ni, and Cu at outfall 007. The reviewer does not recommend any additional stormwater-related monitoring for this outfall like in the draft permit for Duke Energy's Plant Allen Steam Station (where stormwater combines with smaller wastewater flows) Permittee contact: Robin Bryson, (919) 546-3962 No questions for contact at the time of permit drafting 1 Q• question? a ANSWER answer. 2 Q• question? a ANSWER answer 3. Q question? a ANSWER answer. Page 5 of 8 NCS000550 SPU Power Plant Permit Strategy (Beginning 2009) In recent years, the Stormwater Permitting Unit has recognized the complex issues associated with coal - burning power plants and the increased attention on coal ash storage, use, and disposal at these sites Data on stormwater discharges from these plant sites is limited because the focus has traditionally been on wastewater Regions have also voiced concern about potential contamination from metals in stormwater discharges associated with the activities at these sites After researching constituents these activities or materials may introduce to the power plant property (and with them potential for stormwater pollution), the Unit formulated a strategy for these renewal permits Basis. Draft RTI Study ('Human and Ecological Risk Assessment of Coal Combustion Wastes; RTI, August 2007) and discussions with Robert Schreusdale of RTI suggest these metals may signal contamination problems SPU also discussed contaminants with Duke University researcher, Dr Avner Vengosh, who researched the TVA ash pond spill in Dec 2008 in Kingston, TN (Mtg with SPU on May 4, 2009). In addition, RRO/DWQ has sampled discharges from cogeneration plants in the FRO area and flagged metals of concern Overall, we have very little data with which to characterize stormwater discharges from this industry, but we know there is a concern and need for better understanding about possible stormwater pollution from activities here. (FYI - Cost of clean mercury method around $100.) Basis. Power plants area potential major source of mercury, and although some Hg maybe regional, there is a risk that significant quantities come from the activities at the plant itself While wastewater permit limits are calculated based on low stream flow and high wastewater effluent f.'ow conditions -- and sometimes do not warrant the lower -detection method—stormwater contributions vary broadly and do not change the bio -accumulative nature of methyl -mercury. SPU recognizes the complexity of regional air transport and deposition, as well as the cost and resources involved in clean mercury sampling protocol, and therefore will exempt Hg from monthly monitoring in the tier structure However, if mercury data suggest a problem driven by sources or activities at the plant, DWQ should investigate further and could require additional monitoring in the future Basis: conventional pollutants associated with types of activities here Note -include provision to allow pH values below benchmark if facility can document rainfall pH is as low or lower at time of sampling. Basis Consistency with current draft General Permits and to facilitate prompter awareness of monitoring results at the regional office level. Page 6 of 8 NCS000550 example, plants might consider installing bioretention cells for drainage areas where metals are a problem and monitor for effectiveness, in exchange for decreased monitoring frequency and/or no benchmark trigger We -will also consider relieving monitoring if the facility can demonstrate levels are not attributable to, or else not able to be separated from, industrial activities SPU will work with the regional offices to address situations on a case-by-case basis Basis- SPU recognizes the ubiquitousness of copper and zinc, and the low benchmark concentrations for metals like Cd, but we also know activities at power plants can be contributors of these pollutants. SPU feels alternatives to more monitoring can facilitate solutions and that the permit tier structure isflexible enough to relieve the permittee of monitoring when appropriate under a permit, examine for need to apply storwmater effluent limits.) Federal effluent guidelines apply specifically to the Steam Electric Generating industry, which excludes cogeneration facilities. However, cogeneration plants are similar in many respects, and coal storage and handling activities may even be identical. SPU will consider a tailored approach for certain SDOs based on proximity to coal sources, storage area size, etc Depending on the size and similarity of the coal storage and handling (and perhaps other factors), the permit writer could decide to (a) apply limits initially, or (b) an arrangement where benchmarks mirroring BPT requirements for coal pile leachate in 40 CFR §423 (TSS of 50 mg/1 and pH 6-9 SU) would become limits after two exceedences (i.e., Tier 2 action), or (c) lust impose benchmarks. Basis Federal stormwater effluent limits apply to coal piles at steam electric generating facilities, similarity of cogeneration plants (and even elsewhere) warrant similar scrutiny Other states such as Virginia, Ohio, and Georgia have already imposed the same BPT limits on coal pile runoff and leachate at facilities where coal burning for steam electric generation is not necessarily the primary industrial activity. The flexibility for North Carolina to do the same follows that lead and acknowledges the potential for the same pollution problems Page 7 of 8 NCS000550 Recommendations: Based on the documents reviewed, the application information submitted on May 4, 2011 (fee submitted June 15, 201 1) is sufficient to issuq an Individual Stormwater Permit Prepared by ( Stormwater Permitting Unit for Concurrence by Regional RO Water Quality S Regional Office Staff Comments (attach ` Date (0 Date pages as necessary) Date Date dee cl*w 1j l o,M� c �� av1 LO e0 V 6 J;WL 3LI Fz l` °mss �4�50°ssf�doh yl� deS OOd rn'�70111,-f 15 �rts-' 7r ; �F ej ere)?, ��- � � 5� ice v,)ak �� � p i BC OQ�w�Q t ,jQ4 f�4"'K, Gm u� n `' ��o -�o vol r� �{ZD C �� � g, n�- f Q �J +'�� JI v,f ��5�.3 'IBJ f� 5 ,~ev � � 45 0 e . 0 Caff�y Pe a �°4,6 Page 8 Qf 8 0 .v rte.. ty.0 i Cj �c.9 a V6¢ -s a f rhos ��� b 5> i7 is Ossib[e aaG(��er� ice%; > �V e� le