ML19079A067

Submittal of 2019 Intake Forebay Aeration Plan

ML19079A067
Person / Time
Site:	Sequoyah
Issue date:	03/20/2019
From:	Garland M Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TN0026450
Download: ML19079A067 (3)

Text

Tennessee Valley Authority, Sequoyah Nuclear Plant, P.O. Box 2000, Soddy Daisy, TN 37384 March 20, 2019 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001

Subject:

Sequoyah Nuclear Plant, 2019 Intake Forebay Aeration Plan Attached is the 2019 Intake Forebay Aeration Plan for Sequoyah Nuclear Plant.

Respectfully, lillicent Garland Environmental Scientist

M Tennessee Valley Authority. 1101 Market Street, BR 4A. Chattanooga, Tennessee 37402-2801 March 14, 2019 Ms. Jennifer Innes Program Manager Chattanooga Environmental Field Office Division of Water Resources 1301 Riverfront Parkway, Suite #206 Chattanooga, Tennessee 37402

Dear Ms. Innes:

TENNESSEE VALLEY AUTHORITY (TVA) - SEQUOYAH NUCLEAR PLANT (SQN) -

NPDES PERMIT NO. TN0026450 - INTAKE FOREBAY AERATION PLAN In accordance with Part III.I of the subject permit, please find enclosed the revised plan for providing supplemental aeration in low-oxygen zones of the SQN intake forebay area to serve as a fish refuge.

Since SQN does not have a permanent aeration system installed, the plan has been updated to include an action value to bring onsite atemporary compressor when dissolved oxygen in the intake forebay decreases below 3.5 mg/L. Dissolved oxygen (DO) measurements will continue to be collected at the SQN intake skimmer wall and aeration ofthe intake forebay will be initiated when DO concentrations decrease below 3.0 mg/L.

If you have any questions, please contact Millicent Garland at (423) 843-6714 or bv email at mrmoore@tva.gov.

Sincerely, If Matthew Rasmussen Site Vice President Sequoyah Nuclear Plant Enclosure cc (Enclosure):

nl^JSff Division ofWater o Resources US- NuclearR^ulatoryCommission Attn: Document Control Desk Tennessee Department of Environment Washington DC 20555 and Conservation (TDEC)

William R. Snodgrass Tennessee Tower 312 Rosa L Parks Avenue, 11th Floor Nashville, Tennessee 37243

TVA SEQUOYAH NUCLEAR PLANT NPDES PERMIT NO. TN0026450 INTAKE FOREBAY AERATION PLAN From May 1to September 30, dissolved oxygen (DO) sampling of the SQN intake forebay will be conducted to monitor for low DO conditions which could contribute to a fish kill. DO measurements will be collected at the skimmer wall approximately 14 meters below the top of the wall. This depth corresponds to approximately the center of the submerged opening beneath the skimmer wall. TVA will also perform visual inspections of the SQN intake forebay for signs of fish distress at the water surface.

TVA will begin to sample the SQN intake forebay at least once per week beginning May 1of each calendar year. If the DO decreases to below 4.0 mg/L, TVA will increase DO sampling to a minimum of three times per week. If the DO decreases to below 3.5 mg/L TVA will ensure the temporary compressor is brought onsite, functioning properly, and available for operation If the DO decreases to below 3.0 mg/L, TVA will place the aeration system in service.

While aeration is in service. DO sampling frequency will be reduced to aminimum of once per week. The aeration system will be removed from service if the DO increases to 40 mg/L or higher. If the aeration system is removed from service, DO sampling will resume at aminimum or three times per week to ensure conditions remain stable.

If sampling demonstrates DO conditions remain stable or increasing above 4.0 mg/L samplinq frequency w.ll be reduced to aminimum of once per week. If the sampled DO again drops below 4.0 mg/L, TVA will resume sampling at aminimum of three times per week until the uncrease ab 'S a9a'n P'aCed '" SerV'Ce °rthe °° conditions a9ain become stable or If the measured DO remains stable above 4.0 mg/L after September 30 of each calendar year

<< hT?^ W'"rS susPended lf afish ki" is observed in the SQN intake forebay which b TVA-!fJlS TVA s standard'°h operating D° T^0"8' ' Wi"for n0tify procedures thereporting.

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