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Home My WebLink AboutNC0000400_Memo_Wasteload Allocation_19961014 10!17/1996 12: 10 7042516452 PAGE 02 DRI-P & £ Fax:919-777 71.y Oct 14 '96 16:13 P.Cf?i2G v DIVISION O WATER QUALITY Octoba 14, 1996 MemoMdum To: Fonz+est Westall hike parr From: Susan A. Wilso� Paul ClarkP6 G Subject: Mining Va6liti--s on tlx North Too River Please z:vicw the unclosed supplemtri,effluent sheets,and spec-wl oondidolts(tldnus auy ttormwater Iaaguage,if applic ILN)regsr4ing the renewal of the mining/processing facilities located on tb,--North Toe River in the French Broad River Basin. The following, summwizes the F&E's review Cf the facilities: • No-changes are p�reposed to the fluoride loadings ai each facility[rcf.SWT's letter 61'�:l l95I. The MiEUnit would like to be involved in the future re-aliocafiott developulcat of fluotidc at tlirse-fac0itim. ME recommeuds effiueat monitoring fxquencia4(TF,TSS)of weekly for facilities <1 M(rD; daily for facilities}I MUD [most facilities reflect this fr Nueucy]. P&B re,,,om=ads that upstream monitoring be weckl y for facilities<l MGD; 3/week for facilities> I NGD. 'Phis should provide the Division ample data to I-,vieW during tho nett pan-nit cyck. [Sornc facilities ci rrently have daily insw---an monitoring]. • p s iwommeuded by your offices chloride monitoring has be&-n irnplemeztted quarterly (during d=burnt months as toxicity testing). C .Effluent settleable solids,pH,and turbidiiy monitoring have been contillued on a daily frequency. Reviewed by: co Permits Eugir=rjng: (b MINING FACILITIES,NORTH TOE RIVER NOTES TO FILE NC0000175 (Unimin Quartz). Located at River Mile 28.6, this facility is the last mine of the five in close proximity. This facility was recently permitted to construct a tertiary treatment system to meet a fluoride limit of 109 lbs/day [see note under NC0000361]. Stormwater is covered under the NPDES permit. This is classified as a'MAJOR'permit. Instream total fluoride data indicate some elevated fluoride levels both up and downstream. DWQ is aware of the potential over-allocation of total fluoride [SWT letter 6/21/95]. [See memo to ARO 10/14/96] l� October 15, 1996 MINING FACILITIES, NORTH TOE RIVER NOTES TO FILE NC0000361 (Schoolhouse Quartz). Located at River Mile 41.5, this is the first mine discharge of the five within close proximity. This facility was recently permitted to construct a tertiary treatment system to meet a fluoride limit of 109 lbs/day. The UNIMIN facility NC0000175 traded 1091bs/day fluoride load to the Schoolhouse facility, which subsequently reduced its existing load of 219 lbs/day to 109 lbs/day. Stormwater is covered under GP NCG020112. Stormwater from process area is routed to the emergency pond and recycled back to the WWTP(per Roy Riddle 10/12/96). This is classified as a'MINOR' permit. Ms facility has not been discharging process wastewater,but has had incidental discharges from rain events. No instream monitoring has been performed. ;See memo to ARO 10/14/96] 00- October 15, 1996 MINING FACILITIES, NORTH TOE RIVER NOTES TO FILE NCO084620 (Unimin Crystal). Located at River Mile 33.8, this facility currently discharges to the Feldspar plant(NC0000353). UNIMIN requested an increase in flow from 0.173 MGD to 0.36 MGD for incidental wastewater associated with the process. The facility is to begin discharging directly via this permit in the near future. The increase in flow increased the IWC, and consequently, the toxicity testing percentage. IWC based on 7Q10s=41 cfs and 0.36 MGD permitted flow. (IWC= 1.3%) This is classified as a'MINOR' permit. There has been no direct discharge from this outfall, therefore no instream data have been taken. [See memo to ARO 10/14/96] October 15, 1996 MINING FACILITIES, NORTH TOE RIVER FACILITIES: NC0000361 (Schoolhouse Quartz). Located at River Mile 41.5, this is the first mine discharge of the five within close proximity. This facility was recently permitted to construct a tertiary treatment system to meet a fluoride limit of 1091bs/day. The UNIMIN facility NC0000175 traded 109 lbs/day fluoride load to the Schoolhouse facility, which subsequently reduced its existing load of 2191bs/day to 109 lbs/day. Stormwater is covered under GP NCG020112. NC0000353 (The Feldspar Corporation). Located at River Mile 33.8, this facility has phased effluent limits. After Unimin Crystal begins to discharge directly to North Toe River,Feldspars total fluoride monthly average limit will decrease from 225 to 174 lbs/day. As noted in Mike Parker's staff report (7/18/96), the facility has never discharged from outfalls 002 and 003 (both of which are non-contact cooling water discharges). Can one or both of these outfalls be deleted since it appears the facility is not discharging from these outfalls (are these routed to the treatment plant?) P&E is investigating stormwater permitting status at this facility. After computer server becomes operational. stormwater permitting status will be updated. NC0084620 (Unimin Crystal). Located at River Mile 33.8, this facility currently discharges to the Feldspar plant(NC0000353). UNIMIN requested an increase in flow from 0.173 MGD to 0.36 MGD for incidental wastewater associated with the process. The facility is to begin discharging directly via this permit in the near future. The increase in flow increased the IWC, and consequently,the toxicity testing percentage. NC0000400 (K-T Feldspar Corporation). Located at River Mile 29.2, this facility does not have a non-contact cooling water discharge. The Biocide Condition will be omitted from this permit, unless the region provides a reason for retaining this condition. Review of instream monitoring data for the period January 1993 through July 1996 indicated six violations of the fluoride water quality standard at the downstream station. Feldspar facility (NC0000353) did not have any violations over the same time period. P&E is investigating stormwater permitting status at this facility. After computer server becomes operational, stormwater permitting status will be updated. NC0000175 (Unimin Quartz). Located at River Mile 28.6, this facility is the last mine of the five in close proximity. This facility was recently permitted to construct a tertiary treatment system to meet a fluoride limit of 109 lbs/day [see note under NC0000361]. Stormwater is covered under the NPDES permit. R MINING FACILITIES ON THE NORTH TOE RIVER Permit Limits and Monitoring Requirements 6:7z' c� Facility Unimin Schoolhouse Qtz. Feldspar Unimin Crystal K-T Feldspar NPDES No NC0000361 NC0000353 I NCO084620 NC0000400 Mon. avg. Dail.max. Frec I Mon. avg. flail.m.;.%. Freq. Mon. av . Dail.max. Fre4 . Mon. avg. Dail. max. Fre . PF(MGD) 2.16 3.5 R 4bxjw 3 1.73 - I TF(#/da ) 109 218 daily 174 348 daily 0 100 weekly 132 264 week) TF(mg/1) 6.1 12.1 6 12 135 70 9.1 18.2 TSS(#/da ) 450 721 daily 1568 3137 daily 86.6 173.2 weekly 1240 2480 weekly TSS(mg/1) 25 40 54 108 6U 120 86 172 SS monitor daily monitor daily monitor daily monitor daily pH (SU) 6-10 daily 6-10 daily 6-10 daily 6-10 daily Turb(NTU) 10 daily 10 • daily 10 daily 10 daily Tox P/F 10% Qtrl P/F 1 1%n Qtrly LC50>65%Qtrl P/F 6% Qtrl U,D TF,Turb TF,Turb, TF(wkly) TF,Turb, (daily) pH Turb, pH (daily) pH(daily) (daily-- 3/week) I a7 Facility Unimin Qtz Unimin Qtz(processing-new) NPDES No NC0000175 NCO085939 Mon. aviz. Dail.max. Freq. Mon. avg. Dail.max. Freq. PF(M D) 3.6 U•682 TF(#/da ) 218 436 daily 200 400 weckl TF(mg/1) 7.3 14.5 35 7 ;G TSS(#/da ) 1320 2640 daily 142 284 week) TSS(mg/l) 44 8 25 5 SS monitor daily monitor daily pH (SU) 6-10 daily 6-10 daily Turb(NTU) 10 daily 10 weekly Tux P/F 11%n Qtrl P/F 1.15% Qtrl U,D TF,Turb TF,Turb pH (weekly) (daily-- 3/week) "I'I IIS IS'fl III CURREN"I'MONITORING AND LIMIT SCHEME FOR THE MINING FACILITIES AS OF 10/96. October 16, 1996 �GytrGCCl' �-w,.'fS � �C-�dS�Qr/ c1(/Q�7Z a✓VG'GvG7�7�ri1-� tlY vs- �s %. SY A,. 7(1,f Ldq-D bus re/ e-- , • M