ML20077C248

Discusses Licensee Request for Relief from Ph Limitations in Plant Current Vpdes Permit at Outfalls 003 & 004

ML20077C248
Person / Time
Site:	North Anna
Issue date:	11/22/1994
From:	Marshall B VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	Bambacus S VIRGINIA, COMMONWEALTH OF
References
NUDOCS 9412010063
Download: ML20077C248 (5)

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5000 Dominion Boulet ard Glen A!!cn, Virytma 23060 November 22, 1994 VIRGINIA POWER l

l Suzanne E. Bambacus Water Enforcement Department of Environmental Quality 629 East Main Street Richmond, VA 23219 RE: NORTH ANNA POWER STATION, VPDES PERMIT #VA0052451

Dear Ms. Bambacus:

As Daniel James of my staff has discussed with you, we have requested relief f rom the pH limitations contained in North Anna Power Station's current VPDES permit at Outf alls 003 and 004. This issue has been discussed with the staff of the Valley Regional Office and it appears that a Consent Special Order may be the only means by which this relief can be allowed.

-The present VPDES permit imposes, among other limitations, pH limits of 6.0 to 9.0 on the various internal outfalls. Until relatively recently, compliance with these limits has not been a major problem. Reductions in process water losses leading to Outfall 004 did eventually cause an effluent pH increase which has been treated during recent years and was intended to be addressed by the next permit application. Current station equipment replacements and improvements will create a pH increase at Outfall 003 that will not be able to be treated to meet current permit limits. This will occur before the issuance of the next permit.

We are therefore asking that the pH limitations on these outfalls be removed, or excursions excused, for the remainder of the current permit term. It is anticipated that these discharges, and their limit ations , will be more appropriately addressed by the next permit. The current permit expires October 2, 1995, and application for permit reissuance is currently under preparation.

The following factors are involved in the creation of the present situation and bear on this current issue:

• The past permit application described the station outfalls as discharging to " surface waters" which, in retrospect, appears to have been construed as " state waters" and resulted in effluent limitations appropriate to discharges to state waters being applied to internal outfalls.

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Suzanne E. Bambacus Noyember 22, 1994 Page 2

• Outf all designations in the current permit are misleading as the numbers assigned to Outfalls 003 and 004 would indicate direct discharges to state waters. In actuality, 003 and 004 could more accurately be described as internal to internal outfalls. The piping identified as 003 discharges into the cooling water Outfall tunnel inside of the station that leads to the discharge canal.

004 discharges to the head of the discharge canal. The discharge canal carries the cooling water flow, and the effluents of other internal discharges, to the Waste Heat Treatment Facility (WHTF).

The WHTF eventually discharges to state waters at Dike 3. The WHTF outfall is currently designated as 010. Under conventional nomenclature, the WHTF discharge would be designated as outfall 001.

• The discharges at outfalls 003 and 004 do not have any direct impact on state waters. In fact, both of these discharges are so l small with respect to the flow of cooling water, approximately one million gallons per minute, that they would not be expected to have any detectable or detrimental impact on water quality within the

-discharge canal, much less to state waters at the final discharge point.

• If high pH discharges from 003 and 004 could have any environmental impact at all, either within the discharge canal and the WHTF, or to state waters, this impact would be beneficial. Due to natural causes and acid mine runoff inputs, the waters of Lake Anna are somewhat acidic and could benefit from some higher pH input.

• The presence of the WHTF following the discharge canal, prior to discharge to state waters, should be recognized as not the usual situation as compared to other f acilities tnat employ a non-contact cooling water flow. The huge quantity of water in the WHTF provides a very significant assimilative ability for any small amounts of higher pH discharges, as well as other contaminants.

• The nature of the WHTF should also enter into evaluations of discharges from the station. Although designated as a treatment community, facility, the WHTF supports a thriving biological possibly richer than similar " lakes" without power station discharges. This fact is not only evidence of the benign, or even beneficial, nature of the station's discharges but provides a convenient indicator or "early warning system" of any detrimental impact from the internal discharges, long before any discharges could enter state waters.

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1 Suzanne E. Bambacus November 22, 1994 Pa'eg 3

• We are aware of the ef fluent guidelines that may have led to the inclusion of the present pH limitations in the current permit.

However, we believe that they should be applied as " guidelines" and that evaluations of all other aspects of a specific facility must I also be applied in the determination of limitations and conditions l appropriate in a case-by-case basis. For example, we have another f acility where assessment of ambient conditions, such as the low pH of the lake waters, during permit development resulted in a permit  !

requirement to discharge high pH waters for a beneficial '

environmental impact. Also, as precedent in this issue, in a policy decision involving a Philadelphia Electric Company facility )

cooling water discharge, EPA stated that " (i) t was decided that 1 waste streams could be combined with cooling water for the sole purpose of pH neutralization, as long as the final discharge was in the was in the range of 6 - 9."

The reasons leading to the need for permit limitations relief for ]

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the specific outfalls are: l l

.Outfall 003, Clarifier-Presently, the Unit 1 steam generator blowdown system produces an effluent with a pH of about 9.3. This unit's steam generators were replaced this past year. The Unit 2 system pH runs about 8.5 due to boron addition, which will be reduced after the steam generators have been replaced. Combining the two has produced a pH below 9.0, the upper permit limitation, at Outfall 003.

The station is making preparations for replacement of steam generators in Unit 2 during the first part of 1995, Once the steam generator replacement and ancillary improvements are completed, the steam generator blowdown system discharge to Outfall 003 will have a pH between 9 and 10. The normal discharge rate will be 105 gallons per minute and the maximum will bc 150 gpm. The other characteristics of this discharge will be:

Boron 3.43 ppm Ethanolamine 5.0 ppm Ammonia 1.2 ppm Silicon Dioxide 0.020 ppm Hydrazine 0.370 ppm Iron 0.12 ppm Copper 0.003 ppm

J Suzanne E. Bambacus November 22, 1994 Page 4 Various methods to treat this discharge to bring the pH below the upper permit limitation of 9.0 have been investigated and found to be not viable. Since any equipment installed at the nuclear power station must also meet NRC standards and approvals, the costs would be unacceptably high.

Outfall 004, Oil & Water Separator-Previous improvements in station processes reduced various water leaks, condensate losses and drip inputs to the sumps which discharge to this outfall that often result in a pH slightly greater than the permit limit of 9.0 in the sumps.

For some time, the station has been treating the sumps with citric acid to reduce the pH prior to discharge. This treatment is being carried out by a temporary system and, primarily, manual controls that impact station operating resources. While it is possible to continue this operation, it essentially amounts to addition of another pollutant to the station's discharges for no purpose other than to make a pH

_ adjustment which should not be necessary.

As indicated above, it is intended that our request for relief from the pH limits at Outfalls 003 and 004 be for the remainder of the term of the current permit. In application for permit reissuance, we intend to request that the discharge canal be designated as the first internal outfall for North Anna and that the applicable pH limits apply at that point. It is anticipated that our subsequent permit will, based on the factors above, contain more appropriate limitations for this f acility and obviate the need for this relief.

Supporting information, documentation and data for the above issues and discussions are available if needed. If you have any further questions, please feel free to call me at (804) 273-2990 or Daniel James at (804) 273-2996.

Sincerely,

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B. M. Marshall, P.E.

Manager Water Quality

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Suzanne E. Bambacus No,vember 22, 1994 Page 5 L cc: Janardan R. Pandey Water Regional Office Department of Environmental Quality P.O. Box 268 Bridgewater, VA 22812 U.S. Nuclear Regulatory Commission Region II 101 Marietta St., NW Suite 2900 Atlanta, GA 30323 Re: North Anna Units 1 & 2 Docket Nos. 50-338/50-339 License Nos. NPF-4/NPF-7 U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Re: North Anna Units 1 & 2

_ Docket Nos. 50-338/50-339 License Nos. NPF-4/NPF-7 Mr. R. D. McWorter NRC Senior Resident Inspector North Anna Power Station

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