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HomeMy WebLinkAboutNC0000396_Fact Sheet 2001_20010412 • NCDENR / DWQ FACT SHEET FOR NPDES PERMIT DEVELOPMENT Carolina Power and Light- (Asheville) NPDES No. NC0000396 Facility Information (1.)Facility Name: Asheville Steam Electric Plant (2.)Permitted Flow,MGD: No limit for 001 (6.) County: Buncombe or 002. (3.)Facility Class: NA (7.) Regional Office: Asheville (4.)Facility Status: Existing (8.) USGS Topo Quad: F8NE (5.)Permit Status: Renewal Stream Characteristics (1.)Receiving Stream: French Broad River, Lake Julian, and UT Powell Creek (2.)Subbasin: 040302 (6.)Drainage Area(mi2): 655 (3.)SIC Code: 4911 (7.)Summer 7Q10(cfs) 375 (4.)Stream Class: C (8.)Average Flow(cfs): 1680 (5.)303(d)Listed: NO (9.)IWC(%): 1.43%(001) Conditions Incorporated into Permit Renewal Proposed Conditions Parameters Affected Basis for Condition(s) Change stream class from WS-IV to Stream Classifications Based on stream reclassification on Class C waters for French Broad 4/1/96. For French Broad River.C River,Lake Julian,and UT Powell Class extends from Mills River to the Creek. NC/TN state line. Based on current C class,DEH permit review is no longer necessary. Change toxicity test limit from Outfall 001-toxicity test limit Outfall 001 (Ash Pond)is a quarterly acute to quarterly chronic continuous discharge to French at 1.4%effluent concentration. Broad River. In 2000,the max monthly average flow was 3.5 MGD, the s7Q 10 is 375 cfs.resulting in an IWC= 1.4%. Chronic testing is more appropriate for this discharge. Add pH effluent limit of 6 to 9.and Outfall 001-effluent pH limit Per 40 CFR 423.12.BAT requires pH change monitoring frequency from limits of 6-9 for all direct discharges 2/Month to Weekly. except once through cooling water. Per 15A NCAC 2B.0500,pH effluent monitoring for electric/gas services is weekly. Delete monthly monitoring for Fe. Outfall 001-As.Cu,Se.Fe Based on RPA results and chronic and maintain monthly monitoring for WQS,max predicted Fe effluent As.Cu.Se. cont.is only 1.5%of allowable cone. while values for As.Cu,and Se are 17%.20%.and 60%,respectively. Toxicity test results have indicated no acute toxicity at this outfall. NPDES PERMIT FACT SHEET CP&L-Asheville Page 2 NPDES No. NCO000396 Extend the Section 316(a)thermal Outfall 002-Thermal Variance CP&L has requested continuation of variance for the duration of this the thermal variance granted under permit. Section 316(a)of CWA. The thermal variance requires reapplication at permit renewal. Annual Environmental Monitoring Reports have shown no changes in biotic community of Lake Julian which would impact the previous 316(a) determination. Also,the plant operating conditions and load factors are unchanged,and there have been no changes to the Asheville plant discharges that could interact with the thermal discharges. Add weekly pH monitoring. Outfall 002-pH No pH limit required for once through cooling water,but 15A NCAC 2B.0500 specifies weekly pH monitoring. Change effluent monitoring from Outfall 002-Copper Suspected copper source(copper monthly to quarterly. condenser tubes)were replaced with stainless steel in 1994,and DMR data has shown no detection(<10 ug/1)for 25 of 26 events. Recommend that facility analyze source water for copper,which might contribute to copper detection. Maintain TRC limit as an Outfall 002-TRC Per EPA Guidance material instantaneous max,and provide definition. Clarify in Effluent Sheet that Outfall Outfall 004-internal outfall If utilized,Outfall 004(chemical 004 is an internal outfall,rather metal cleaning waste)would than direct discharge. discharge to the new ash pond or old ash pond. This wastestream is typically incinerated. Delete limit and monitoring. Outfall 004-pH This limit was incorrectly applied in the previous permit. Discussion with EPA HQ indicates that the pH limit should be applied only to direct discharges. Outfall 004 is an internal outfall to the ash pond. Change measurement frequency Outfall 004-measurement frequency The text change reflects the from"daily"to"per discharge event" intermittent batch discharge. Add stormwater outfall requirements Stormwater outfalls(SW-1 through Stormwater from access roads used and stormwater boilerplate language SW-6) to transport coal/oil truck deliveries for new and current access roads. are subject to NPDES stormwater permitting All access road outfalls discharge to Lake Julian with exception of SW-5,which discharges to UT Powell Creek. All of these direct discharges are subject to stormwater requirements. Stormwater from other areas which discharge indirectly to surface waters(e.g.,plant area,parking lots, oil storage and handling facility) discharge to the ash pond and are already subject to treatment and effluent limits. No additional stormwater requirements are considered necessary to achieve water quality standards. NPDES PERMIT FACT SHEET CP&L-Asheville • Page 3 NPDES No. NC0000396 Assign stormwater Outfall SW-3 as a Stonnwater outfall-SW-3 Based on the same industrial activity representative outfall for monitoring. at each access road stormwater outfall,assign SW-3 representative outfall status. Representative outfall status is provided by Special Condition A(9)(a). Move to bottom of Effluent Sheet for Part III.F.Biocide Condition Formatting improvement. Outfall 002. Delete Special Conditions Part III.-Special Conditions G,H,I, These generic conditions are not J consistent with any other CP&L permits,or considered necessary to achieve water quality stanards. Special Condition I(BMP Plan)is already required for direct stormwater discharges,while indirect discharges are already subject to treatment(via ash pond) and effluent limits for appropriate parameters. Special Condition J (FIFRA)is considered not applicable, since the facility does not use insecticides or rodenticides. Current facility uses include application by a licensed termite contractor inside buildings.as well as herbicide application for weed control. Boilerplate language(Part III.C) requires the facility to notify the Division of any anticipated increase ip discharge of toxic pollutants beyond current conditions. Change permit expiration date to Expiration Date Current permit expired on 9/30/00. 4/30/05. Renew per Basin Renewal Schedule. NPDES PERMIT FACT SHEET CP&L-Asheville Page 4 NPDES No. NC0000396 PROJECT NOTES Summary • This permit was last issued in August 1995 and expired on September 30, 2000. The facility submitted EPA Application Forms 1 and 2C on March 30, 2000. • This is a permit renewal for an electric generating facility that uses steam turbine generation (via two coal-fired units with a total net capacity of 392 MW) and internal combustion generation (via two IC turbines with a total net capacity of 330 MW). • The facility discharges to subbasin 040302 in the French Broad River Basin. Discharges are 100% industrial,with domestic flow piped to a municipal POTW. Discharge from the ash pond (Outfall 001) is to the French Broad River.while discharge from once-through cooling water(Outfall 002) is to Lake Julian. There are also six stormwater outfalls located along vehicle access roads that discharge to either Lake Julian or an unnamed trib to Powell Creek. All receiving waters are class C, and none are listed as impaired waters in the Draft 2000 303(d) list. The French Broad River eventually flows northwest into Tennessee. • Lake Julian is a 320-acre waterbody constructed in 1963 by CP&L to serve as a cooling water source. The May 2000 Basin Plan reports that the lake is oligotrophic. A 1995 CP&L study found that trace elements in fish tissue were comparable to background concentrations or slightly above, and copper concentrations in fish liver did not indicate any significant uptake of copper from reservoir waters. Discharge from Lake Julian to the French Broad River is extremely rare, and any occurrence would be during periods of heavy rainfall. There is a current Section 316(a) thermal variance for Lake Julian pending renewal. Permit Development This facility is subject to EPA effluent guideline limits per 40 CFR 423- Steam Electric Power Generating Point Source Category. Outfall 001 (New Ash Pond)-Direct discharge to French Broad River. • The previous permit included BPT limits for TSS and O&G. Renew existing limits. Also add BPT pH limit of 6-9 (per 40 CFR 423.12), since limit applies to all direct discharges except once through cooling water. No parameters are water quality limited. A reasonable potential analysis was conducted for arsenic, copper, iron, and selenium, and none showed reasonable potential. Maintain monthly monitoring for all except iron, which represented <2% of the allowable effluent concentration. Some additional metal detections were reported on EPA Form 2C,but values were well below allowable effluent concentrations. Change the toxicity test limit from quarterly acute to quarterly chronic, at a test concentration of 1.4%. This is a continuous direct discharge subject to chronic testing requirements. Outfall 002 (Once-through Cooling Water)- Direct discharge to Lake Julian. • The previous permit included BAT limits for TRC and restrictions on duration of chlorine addition. Renew existing limits. This wastestream is exempted from the BPT pH limit; however, add weekly pH monitoring based on state monitoring requirements for the Electric Services Industry (15A NCAC 2B.0500). There are no water quality limited parameters. • This discharge has a monthly average temperature effluent limit of 44.4°C based on a thermal variance issued under Section 316(a) of the CWA. CP&L has requested continuation of its 316(a) variance for thermal limitations, as required by Part III, Condition K of its current NPDES permit. CP&L has responded to pertinent factors contained in the EPA General Procedure for 316(a)variance renewal. CP&L reports that 1) the plant operating conditions and load factors are unchanged; 2) there have been no changes to the Asheville plant discharges or other discharges to Lake Julian which could interact with thermal discharges; and 3) as documented in CP&L's Annual Environmental Monitoring Reports, there have been no changes to the biotic community of Lake Julian which would impact the previous 316(a) determination. DWQ's Biological Assessment Unit concurs that the reports show no changes in the biological community of Lake Julian. • CP&L has requested deletion of monthly copper monitoring,based on monitoring data over past years below detection limit. Copper monitoring was originally required due to suspected erosion of Unit 1 copper condenser tubes, which were replaced with stainless steel tubes in 1994. NPDES Response: Review of DMR copper data for past 26 months shows 25 months with<10 ug/1,with one detection of 23 ug/I reported in November 2000. Based on very low frequency of detection, change monitoring from monthly to quarterly. Recommend to facility to collect concurrent source water copper data, to evaluate background copper levels. • CP&L has requested the TRC limit be changed from an Instantaneous Max to a Daily Max limitation. NPDES Resvonse: EPA has issued guidance stating that the TRC limit is an instantaneous maximum limit. No change to current permit. Add definition for"instantaneous maximum"to effluent sheet. NPDES PERMIT FACT SHEET CP&L-Asheville Page 5 NPDES No. NC0000396 • The effluent sheet states that simultaneous multi-unit chlorination is permitted. CP&L has requested the term "or sequential" be added after "simultaneous" to reflect the fact that the facility is allowed to chlorinate each unit sequentially as well as simultaneously. NPDES Response: CP&L removed request after further discussion. Internal Outfall 004- (Chemical Metal Cleaning Waste). • Chemical metal cleaning wastes have been incinerated since at least 1999. However, if not incinerated, they may be discharged to either the new ash pond or old ash pond (after receiving DWQ approval). • The previous permit included BAT limits for copper and iron. Renew with same limits. • The previous permit included BPI' limits for pH. Delete this limit and monitoring. Per discussion with EPA HQ (Ahmar Ciddiqui. 202-260-1826) the pH limit should be applied to direct discharges only • There are no water quality limited parameters. Stormwater Outfalls (SW-1,2,3,4,5,6) • In 2000 CP&L discovered three stormwater outfalls on the access road to the Asheville plant which discharge to surface water. The access road is used as a transportation route for coal and oil delivery trucks. Two of the outfalls discharge to Lake Julian and the third outfall discharges to a tributary of Powell Creek. A new access road will be constructed as the primary plant access for coal and oil delivery trucks. Stormwater from the new access road will be routed to the ash pond and to Lake Julian. CP&L would like the reissued NPDES permit to reflect these stormwater discharges, and submitted EPA Form 3510-2F (Application for Permit to Discharge Stormwater Discharges Associated with Industrial Activity) for current and new access roads. Renew with stormwater requirements requirements and boilerplate language for the access roads. Since the industrial activity is similar along the access roads, allow stormwater outfall SW-3 to be designated as a representative outfall for monitoring purposes. Stormwater from other parts of the facility (e.g., plant area, parking lots, oil storage and handling facility) is routed to the ash pond, and is subject to treatment and applicable effluent limits (e.g.,TSS, oil and grease, chronic toxicity testing) prior to discharge. Miscellaneous • Delete Part III Special Conditions G, H, I, J. These are generic statements which are not consistent with other CP&L permits, and are considered unnecessary for the facility to meet applicable water quality standards. • Update stream classification from WS-IV to C for French Broad River, Lake Julian, and UT Powell Creek,based on stream reclassification on 4/1/96. • Change the permit expiration date to 4/30/05 in alignment with the French Broad River renewal schedule. DMR Data. • Effluent Data(001-Ash Pond). For a 14-month period (1/00-2/01), the facility complied with effluent permit limits for TSS and O&G. Monthly average values ranged from: 0.6- 3.5 MGD (flow); <3-19 mg/1 (TSS); <5-6 mg/1 (O&G); <0.5-7 mg/1 (TN); and <0.02-0.1 mg/1 (TP). None of the metals monitored (As, Cu, Se, Fe) showed reasonable potential to exceed chronic criteria. Quarterly acute toxicity testing reported 18 of 18 passing tests between 1997-01, thus acute toxicity at this outfall is not anticipated. • Effluent Data (002- Once Through Cooling Water). For a 14-month period (1/00-2/01), the facility complied with effluent permit limits for Temperature and TRC. The permit limit for temperature is 44.4°C (variance condition, monthly average), and the highest monthly average was 43.0°C (July). Most TRC values were below 100 ug/1,versus a limit of 200 ug/l. Since 1999,monthly copper values have been reported as <10 ug/1, with a single detection of 23 ug/1 in November 2000. Monthly average flows have ranged from 183-305 MGD. • Effluent Data (004- Chemical Metal Cleaning Waste). There have been no reported discharges since at least 1999, as this waste stream has been incinerated. • Instream Data. There is no instream monitoring requirement for the current NPDES permit. Compliance History • The facilty paid a civil penalty of $4,207 in May 2000 for beginning construction of an oil/water separator before an ATC permit had been issued. No previous NPDES enforcement actions have been taken against the facility. Wasteload Allocation. • The last WLA on file was completed in 1995. The WLA reports a s7Q 10=375 cfs for the French Broad River. Asheville Region Data. • ARO conducted a Compliance Evaluation Inspection on 6/13/00 and found the facility to be operating in compliance with its NPDES permit. Approximately 7 years of ash storage were reported remaining in ash pond (Outfall 001). The last staff report in 1995 recommended permit renewal. NPDES PERMIT FACT SHEET CP&L-Asheville Page 6 NPDES No. NC0000396 Proposed Schedule for Permit Issuance Draft Permit to Public Notice: 05/09/01 Permit Scheduled to Issue: 06/25/01 State Contact If you have any questions on any of the above information or on the attached permit, please contact Tom Belnick at (919) 733-5038, extension 543. Copies of the following are attached to provide further information on the permit development: • Reasonable Potential Analysis (majors only) • Draft Permit 61641 NPDES Recommendation by: C/4/11 Signature Date Regional Office Comments Regional Recommendation " "`61 ,4 /kiii 5+0 bu Signature Date Reviewed and accepted by: Regional Supervisor: Signature Date NPDES Unit Supervisor: Signature Date