Tuesday, May 24, 2016

PRM 50-93/95: Recent email from Doyle, NRC to Mark Leyse

Status of PRM-50-93/95
5/24/2016 1:52:17 P.M. Mountain Daylight Time

To: Send IM to: markleyse@gmail.commarkleyse@gmail.com
CC: Send IM to: Bobleysebobleyse@aol.com, shadis@prexar.com, Scott.Burnell@nrc.gov, Cindy.Bladey@nrc.gov

Mr. Leyse,

I am writing to provide an update on your letters dated November 17, 2009, and June 7, 2010, in which you submitted petitions to the U.S. Nuclear Regulatory Commission (NRC).  In your letter dated November 17, 2009, you requested that the NRC amend the regulations in Title 10 of the Code of Federal Regulations (10 CFR) Part 50 and Appendix K to Part 50 to require that the rates of energy release, hydrogen generation, and cladding oxidation from the metal-water reaction considered in emergency core cooling system evaluation calculations be based on data from multi-rod (assembly) severe fuel damage experiments.  In addition, you requested that the NRC create a new regulation to establish a minimum allowable core reflood rate in the event of a loss-of-coolant accident (LOCA).  In your letter dated June 7, 2010, you requested that the NRC order Vermont Yankee Nuclear Power Station (Vermont Yankee) to lower the licensing basis peak cladding temperature to 1,832 degrees F in order to provide a necessary margin of safety in the event of a LOCA.

The NRC docketed your November 17, 2009, letter as petition for rulemaking (PRM) 50-93.  A notice of receipt and request for public comment on PRM-50-93 was published in the Federal Register on January 25, 2010 (75 FR 3876).  Your letter dated June 7, 2010, was submitted as a petition for enforcement action under 10 CFR 2.206.  On August 6, 2010, the NRC denied your § 2.206 petition because it did not demonstrate that Vermont Yankee was in violation of any NRC regulations.  Because your § 2.206 petition asserted that there were generic inadequacies in NRC regulations, the NRC decided to review it under 10 CFR 2.802 as a petition for rulemaking and docketed it as PRM-50-95.  Because PRM-50-93 and PRM-50-95 address similar issues, the NRC consolidated these two petitions for review as a single petition for rulemaking activity.  Another Federal Register notice was published on October 27, 2010 (75 FR 66007), and the comment period was reopened.  The public comment period ended on November 26, 2010.  Thirty-two public comments have been received to date on the combined petitions.  These comments have been posted at regulations.gov (ID:  NRC-2009-0554).

The NRC staff is considering the merits of your PRM and the public comments received.  As described in the NRC’s letter to you dated August 25, 2011, the NRC has decided to increase the visibility to the public of the NRC’s review of these particular petitions.  The NRC will publicly release its draft interim reviews regarding each group or category of issues on a periodic basis as the review progresses.  These draft interim reviews will be posted on regulations.gov.  So far, the NRC has publicly released four draft interim reviews:

The NRC staff will consider and respond to the comments you made regarding PRM-50-93 and PRM-50-95 at the Commission briefing on public participation in NRC regulatory decision-making on January 31, 2013, in the review of these petitions.

The NRC is considering the remaining issues and will notify you as the draft interim reviews are completed.  Once the petitions have been resolved, a notice will be published in the Federal Register explaining the Commission’s finding.  You will also receive a letter at that time notifying you of the action that the Commission has taken.

Please feel free to contact me at Daniel.Doyle@nrc.gov or 301-415-3748 if you have questions.


Dan Doyle

Project Manager
U.S. Nuclear Regulatory Commission
(301) 415-3748

Leyse Patent: Method to establish the presence of dissolved gas in pressurized water

(Clicking on the above link will not bring up the patent.  However, if you copy it to an email, the patent will appear when clicked on.)

United States Patent 5,621,161
Inventors:Leyse; Robert H. (Saratoga, CA)
Family ID:23663377
Appl. No.:08/419,700
Filed:April 11, 1995
April 15, 1997

Method for monitoring for the presence of dissolved gas in a fluid under pressure

The present invention relates to dissolved gases in fluids under pressure and, more particularly, to relating the electrical resistance of a sensor element to the presence of the dissolved gas.


The presence of dissolved gas in fluid, such as water, under pressure can lead to unacceptable performance of certain support and monitoring equipment in industry. These factors are extremely important in nuclear power plants. In both pressurized water reactors and boiling water reactors, the presence of dissolved gas in reference level pipes for water level detectors leads to outgassing and degradation of calibration. In the case of the water-filled accumulators for an emergency core cooling system, called upper head injection, the presence of substantial amounts of dissolved gas (such as hydrogen and nitrogen) degrades the ability of the system to function and provide emergency core cooling. Dissolved gas is released during rapid pressure reductions which results in expulsion of fluid from reference pipes. This leads to erroneous vessel level readings at a time when there is a critical need for accurate level measurement.

I first wrote the patent application while I was at the Electric Power Research Institute (EPRI).  It is part of an involved situation, but below is the reaction of the nuclear power gang at EPRI.  It is misleading.

The need for the invention, the determination that dissolved gas is present in systems such as upper head injection, was well known to Rossin who wrote the above. Below is a two page memorandum that Rossin received during October, 1984.  The second sentence of the opening paragraph is, "For example, AEOD does not recognize that plant operation with the UHI accumulator water saturated with dissolved nitrogen increases the chance of sustained core uncovery during some accidents."

Several years following the Rossin rejection, EPRI admitted that a problem existed in water level measurements in boiling water reactors (BWRs).  By that time I had been kicked out of the nuclear power division for several years. As of today, I do not have the old files, and the above patent 5,621,141 was not based on those disclosures from 1982. 


 At the Staff‘s request, the BWROG submitted a report on May 20, 1993, discussing the impact of level 84 'P errors on automatic safety system response and operator actions during transients and accidents initiated from reduced-pressure conditions during plant cooldown (shutdown mode). Based on this information, in addition to the January 21, 1993 WNP-2 event, and data from the reference-leg de-gas testing that was conducted by the BWROG, the staff concluded that additional short-term actions needed to be taken for protection against potential events occurring during normal cooldown. On May 28, 1993, NRC Bulletin (NRCB) 93-03, "Reso- lution of Issues Related to Reactor Vessel Water Level Instrumentation," was issued, in which the Staff requested each BWR licensee to implement additional short-term compensatory actions, and to implement a hardware modification to



Monday, May 23, 2016

Link to Leyse-UCLA paper


Opening the above requires some steps:

1. Click on it
2. A box appears, Click on OK
3. A moving arrow then quickly directs you to the down arrow at the top right of the screen.  (That moving arrow moves fast and disappears.) 
4. Click on that down arrow and select Conf_LMWD2003. You will be asked:
5. How do you want to open this file? 
6. Select PDF Viewer Plus SE Application and click OK
7.  The document then promptly appears.




Wednesday, May 18, 2016

UHI: Relatively Recent UHI Correspondence,

Robert H. Leyse
P. O. box 2850
Sun Valley, ID 83353

July 2, 2013

Director, Human Resources
3420 Hillview Avenue
Palo Alto, CA 94304

This augments my letter to you that is dated June 18, 2013.  This letter has improved documentation of the traceability of the shutdown of Duke Power’s McGuire Unit 1 on October 30, 1984, to my NSAC Memorandum, UHI – Ultra Hgh Risk, that is dated October 3, 1984.  For your convenience I am including Enclosures 4, 5, 6 as well as a “new” enclosure 6A. 

Sugnet documented his contact with Duke regarding UHI weaknesses on October 25, 1984, Enclosure 4.  The following two paragraphs are copied from page 2 of my June 18, 2103 letter:

Alerted by Sugnet, Duke checked the status of its UHI systems at McGuire Unit 1 and Unit 2.  McGuire Unit 1 was then shut down on October 31, 1984, and McGuire Unit 2 was operated at 45 percent power. (Enclosure 5)

The periodic test for dissolved gases was only every 18 months; thus it is very likely that Duke’s activities on October 31, 1984, are traceable, via the Sugnet contact, to the Leyse memorandum of October 3, 1984. (Enclosure 6, see yellow highlighting)

This letter has a significant “new” attachment, Enclosure 6A.  The yellow highlighting reveals that Duke concerns with dissolved gases in its UHI system at McGuire began on October 25, 1984, the same date as the Sugnet memorandum.  The normal procedure of sampling for dissolved gases only every 18 months is also highlighted.  McGuire Unit 1 was shut down on October 30, 1984, not October 31, 1984.

Robert H. Leyse

Robert H. Leyse

P. O. box 2850
Sun Valley, ID 83353

June 18, 2013

Director, Human Resources
3420 Hillview Avenue
Palo Alto, CA 94304

I have found the report that I asked you to send on December 31, 2012.  Amy Anderson, EPRI Dallas, wrote me on February 21, 2013, that per company policy that report is no longer available for distribution.

In a nutshell, the following explains my interest.  Enclosed is a copy of an NSAC memorandum from Lang to Layman, December 13, 1984, in which Lang writes in the final paragraph on page 2, “I told Lanning that NSAC valued the technical relationship with AEOD that has existed and that while we feel free to be critical, it is not our practice to write critical memoranda behind his back or to leak memoranda rather than to send them directly.  I expressed regret for the situation that Lanning had outlined.” (Enclosure 1)

Now, Director, Human Resources, the enclosed Lang to Layman memorandum does not include a lot of facts.  Leyse was certainly never aware of any technical relationship with AEOD.  On November 8, 1984, EPRI notified Leyse of his Elimination of Position and Leyse promptly looked for work elsewhere.  Leyse telephoned Keppler of NRC and Keppler paid for Leyse’s trip for his employment interview that took place on November 16, 1984.  Leyse presented Keppler with documentation of his current expertise among which was the copy of the memorandum that Lang asserts was leaked to Keppler.  Keppler asked Leyse if it would be OK if he sent Leyse’s memorandum to others in NRC and Leyse said it would be OK provided Leyse’s identity was not disclosed. (Enclosure 2)

Quickly, there are loads of facts.  Leyse submitted his memorandum, UHI – Ultra High Risk on October 3, 1984.  Leyse discussed his UHI studies at an NSAC Generic Issues Meeting on October 17, 1984, attended  by Rossin, Breen, Layman, Wyckoff, Reuland, Power and Vine (Rossin, Breen and Layman usually did not attend). There were no comments from anyone although Breen appeared disturbed and said he would check the McGuire PRA. (Enclosure 3) 

Breen assigned Sugnet to discuss these matters with his PRA colleagues at Duke.  Sugnet reported on October 25, 1984, that Duke eliminated UHI in its PRA analyses based on Duke’s “…analysis demonstrating that it was not necessary for any LOCA.” (Enclosure 4)

Alerted by Sugnet, Duke checked the status of its UHI systems at McGuire Unit 1 and Unit 2.  McGuire Unit 1 was then shut down on October 31, 1984, and McGuire Unit 2 was operated at 45 percent power. (Enclosure 5)

The periodic test for dissolved gases was only every 18 months; thus it is very likely that Duke’s activities on October 31, 1984, are traceable, via the Sugnet contact, to the Leyse memorandum of October 3, 1984. (Enclosure 6, see yellow highlighting)

The reference to the McGuire Unit 1 UHI system in the proposed ABNORMAL OCCURRENCE REPORT TO CONGRESS FOR FOURTH QUARTER CY 1984 dated January 28, 1985 is significant. (Enclosure 7)

The Sandia work that is referenced in Enclosure 7 turned out to be deficient.  The NRC did not specify the case of improperly functioning level instruments, in which case there was no assurance that the water-filed accumulators had 1800 cubic feet of water, or any water. (Enclosure 8, see yellow highlighting)

Robert H. Leyse