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Comments must be filed by June 21, 2018, 11.59 pm (23.59) EDT (DC-NY). A request for a hearing must be filed by July 23, 2018 https://www.regulations.gov/document?D=NRC-2018-0096-0001 50 mile radius fallout zone for River Bend Nuclear Power Station.

Entergy wants to “relocate the reactor core isolation cooling (RCIC) piping injection point from the reactor vessel head spray nozzle to the feedwater line using the residual heat removal (RHR) shutdown cooling return line,” at River Bend Nuclear Power Station, near St. Francisville, Louisiana. Risk is not merely an academic question at River Bend Nuclear Power Station, as there have been loss of cooling near misses in recent years. This nuclear power station is up for relicensing, too.

The relicensing document simply states: “The vessel head spray function is no longer in use. The vessel vent and head spray nozzle is evaluated with the reactor vessel pressure boundary as a piping component…https://www.nrc.gov/docs/ML1715/ML17153A286.pdf

Entergy also wants to “modify the River Bend Station Technical Specifications (TSs) by relocating specific surveillance frequencies to a licensee-controlled program with the adoption of Technical Specifications Task Force (TSTF) Traveler TSTF-425, Revision 3, “Relocate Surveillance Frequencies to Licensee Control—RITSTF [Risk-Informed TSTF] Initiative 5b.” Additionally, the change would add a new program, the Surveillance Frequency Control Program (SFCP), to TS Chapter 5.0, “Administrative Controls.https://www.regulations.gov/document?D=NRC-2018-0096-0001

It has been previously pointed out that “removing surveillance frequencies from the operating license document obfuscates the minimum requirements, may introduce human error, and limits review by the public.” http://www.copswiki.org/w/pub/Common/M1341/NRC_LBP-12-25_Order_and_Memoranda_Denying_COPS_Petition_to_Intervene.pdf

According to a patent document: “In a reactor pressure vessel of a BWR type reactor, a head spray nozzle is used for cooling the head of the pressure vessel and, in view of the thermal stresses, it is desirable that cooling is applied as uniformly as possible. A conventional head spray is constituted by combining full cone type nozzles…” Excerpted from “Head spray nozzle in reactor pressure vessel“, by Hatano, Shun-ichi, Toshiba, 1990. https://inis.iaea.org/search/search.aspx?orig_q=RN:22026384

Several months ago, information was forwarded to us regarding River Bend Nuclear Power Station stating that a “probe sent through the reactor’s primary reactor coolant system discovered a one foot long ‘loose part’ that has damaged a nozzle on the reactor pressure vessel“. This appears to be related.

Like most BWR nuclear reactors, River Bend, a GE BWR-6/Mark III, was designed with a reactor vessel head spray nozzle. If it was necessary upon its design and construction, then it must remain necessary. The full impact of moving the reactor core isolation cooling (RCIC) piping injection point from the reactor vessel head spray nozzle may be unknown, simply because there is only one nuclear power station exactly like it. There are very few GE BWR-6/Mark IIIs. And, each of them is a unique design and/or construction, as discussed here: https://www.osti.gov/scitech/servlets/purl/6051208 The document goes into detailed analysis of Grand Gulf Nuclear Power Station, but it is larger and of a slightly different design, with a different construction company. Grand Gulf, which is the largest single reactor in the United States, apparently was designed without a reactor head spray nozzle, which is alarming.

The RCIC system supplies the makeup water required to maintain reactor vessel inventory. The turbine-driven pump supplies makeup water from the condensate storage tank (CST) to the reactor vessel. An alternate source of water is available from the suppression pool. The turbine is driven by a portion of the steam generated by the decay heat and exhausts to the suppression pool. This operation continues until the vessel pressure and temperature is reduced to the point that the residual heat removal (RHR) system can be placed into operation. The initial system study is documented in “Reactor Core Isolation Cooling System Performance, 1987-1993” (NUREG/CR-5500, Volume 7 ). The links below provide the current information for the study and latest results….” https://nrcoe.inel.gov/resultsdb/SysStudy/RCIC.aspx

Residual Heat Removal System:
Low Pressure Coolant Injection Mode: auto initiates to restore and maintain desired water level in the reactor vessel following a Loss Of Coolant Accident (LOCA). Containment Spray Mode: condenses steam and reduces airborne activity in the primary containment following a LOCA. (SP and DW spray)…
Shutdown Cooling and Head Spray Mode: removes decay heat from the reactor core following a reactor shutdown and removes residual heat from upper reactor vessel internals during a cooldown
Shutdown Cooling Mode
• Removes decay heat when shutdown.
• Head Spray is used to remove heat from the thick upper head region…
“.
https://www.nrc.gov/docs/ML1125/ML11258A370.pdf

A few more details of the
Residual Heat Removal System
PURPOSES:
Low Pressure Coolant Injection Mode: auto initiates to restore and maintain desired water level in the reactor vessel following a Loss Of Coolant Accident (LOCA). (LOCA).
Containment Spray Mode: condenses steam and reduces airborne activity in the primary containment following a LOCA. (SP and DW spray)
Suppression Pool Cooling Mode: removes heat from the suppression pool.

Residual Heat Removal System
Shutdown Cooling and Head Spray Mode: removes decay heat from the reactor core following a reactor shutdown and removes residual heat from upper reactor vessel internals during a cooldown
Shutdown Cooling Mode
• Removes decay heat when shutdown.
• Head Spray is used to remove heat from the thick upper head region

Conditions
• Reactor at low pressure
• Suction from A recirculation loop suction side
• Return to either recirculation loop discharge side
• Recirculation pump discharge valve shut to ensure flow to the vessel…
“.


Read the entire document here: https://www.nrc.gov/docs/ML1125/ML11258A370.pdf (Head spray shown at the very top.) Related: https://www.nrc.gov/docs/ML1125/ML11258A369.pdf

Excerpted from: “Entergy Louisiana, LLC, and Entergy Operations, Inc., Docket No. 50-458, River Bend Station, Unit 1 (RBS), West Feliciana Parish, Louisiana Date of amendment request: January 29, 2018. A publicly-available version is in ADAMS under Accession No. ML18029A187.

Description of amendment request: The proposed change would modify the RBS Updated Safety Analysis Report (USAR) and Technical Requirements Manual to relocate the reactor core isolation cooling (RCIC) piping injection point from the reactor vessel head spray nozzle to the feedwater line using the residual heat removal (RHR) shutdown cooling return line

Basis: The relocation of the RCIC injection point from the reactor vessel head spray nozzle to the `A’ Feedwater line via the `A’ RHR shutdown cooling return line

The proposed change relocated the injection point of the RCIC flow from the reactor head (RPV [reactor pressure vessel]) to the feedwater line (FWS).

This change will reduce the effects of steam quenching.”
https://www.regulations.gov/document?D=NRC-2018-0096-0001
Then they go on with their usual mindless blah, blah, blah, twisting and contorting things to pretend things are ok, when they are not.

It is unclear if the following makes moving the injection point to the residual heat removal (RHR) shutdown cooling return line more or less dangerous. The fans might make a spray directly on the reactor head more important, not less, for instance. It is worth repeating: River Bend was designed with a reactor vessel head spray nozzle. If it was necessary upon its design and construction, then it must remain necessary. “All of the Mark III plants, with the exception of River Bend, have a containment spray operating mode for their residual heat removal (RHR) systems. In addition to the LPCI mode discussed earlier, RHR can also be used to remove energy from containment when aligned in either the suppression pool cooling mode or the containment spray mode. Two RHR pump trains circulate suppression pool water through two heat exchangers and back to either the suppression pool or the containment spray nozzles. Containment sprays are initiated automatically during a loss-of-coolant accident (LOCA) ten minutes after the containment pressure exceeds the spray initiation setpoint. The containment sprays will condense steam in the containment and scrub non-noble gas fission products. Vacuum breakers are installed in the drywell, which communicate with the suppression pool air space to control rapid weir wall overflow in a large break LOCA. Drywell vacuum relief is not required to assist in hydrogen dilution or to protect the structural integrity of the drywell following a large break LOCA. (River Bend has neither a containment spray system nor drywell vacuum breakers. However, it does have a unique safety-grade fan cooler system.)… At River Bend, fans in the upper dry-well exhaust to the containment air space while return air enters through two lines located just above the suppression pool. Containment purge is provided at each of the plants.https://www.osti.gov/scitech/servlets/purl/6051208

Special Inspection at River Bend: The Chiller Thriller“, by DAVE LOCHBAUM, DIRECTOR, NUCLEAR SAFETY PROJECT | FEBRUARY 24, 2016, 4:51 PM EDT https://allthingsnuclear.org/dlochbaum/special-inspection-at-river-bend-the-chiller-thriller

Special Nuclear Inspection: River Bend Loss of Shutdown Cooling“, by DAVE LOCHBAUM, DIRECTOR, NUCLEAR SAFETY PROJECT | MAY 24, 2016, 5:41 PM EDT https://allthingsnuclear.org/dlochbaum/special-nuclear-inspection-river-bend-loss-of-shutdown-cooling

Some posts discussing the many problems plaguing River Bend Nuclear Power Station:
https://miningawareness.wordpress.com/2016/02/18/lightening-scrammed-nuclear-reactor-lost-cooling-off-for-weeks-on-again-now-off-usnrc-inspection/
https://miningawareness.wordpress.com/2017/10/21/river-bend-nuclear-disaster-would-give-new-meaning-to-lsu-death-valley-comment-deadline-monday-night-1059-pm-central-standard-time/
https://miningawareness.wordpress.com/2016/05/19/defective-breakers-may-cause-increased-release-of-radiation-to-the-environment-at-nuclear-power-stations-schneider-electric-masterpact-defect-strikes-again-at-river-bend/
https://miningawareness.wordpress.com/2017/10/10/louisiana-nuclear-power-stations-dangerous-problems-with-thunderstorms-hurricane-should-serve-as-reminder-petition-to-intervene-deadline-oct-13th-comment-deadline-oct-23rd-relicensing-must-be/
https://miningawareness.wordpress.com/2017/07/14/ge-hitachi-f-up-could-lead-to-inability-to-scram-shutdown-several-us-nuclear-reactors/
https://miningawareness.wordpress.com/2016/05/21/us-and-s-korea-nuclear-power-stations-impacted-potentially-impacted-by-defective-schneider-masterpact-breakers-lists/