sept. 16 letter from nnsa to los alamos national laboratory regarding nuclear safety issues

8/3/2019 Sept. 16 letter from NNSA to Los Alamos National Laboratory regarding nuclear safety issues

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Attachment 1: Status of Plutonium Facility Criticality Safety and Conduct of Operations

Primary Author: C. H. Keilers, Jr. Date: September 16, 2011

The Plutonium Facility (PF-4) has an incompletely implemented criticality safety program. PF-4

technical safety requirements (TSR) require PF-4 to implement and maintain this safety

management program in accordance with Los Alamos National Security, LLC, (LANS) institutional

requirements defined in SD130,Nuclear Criticality Program.

The fact that the program is incompletely implemented is not new but should have been resolved by

now. Since 2006, LANS has slipped implementation milestones three times, primarily due to issues

jointly assigned higher priority by LANS and the National Nuclear Security Administration

(NNSA), such as PF-4 seismic issues. A NNSA review and a LANS Nuclear Criticality Safety

Committee (NCSC) review confirm that implementation of this safety management program by

April 30, 2011 (the latest commitment date) was not achieved.

NNSA has also compared the NCSC reviews preliminary issues against prior issue management

records; many issues persist that have been long-recognized but have still not been properlyaddressed. This reflects poorly on use and maturity of the LANS contractor assurance system.

Furthermore, LANS self-identified 23 PF-4 criticality infractions in FY 2010 and continues on that

trend. Nearly all of the infractions are due to incompletely implemented conduct of operations and,

to a lesser extent, configuration management. These are two other safety management programs

required to be implemented by the TSRs but with longstanding issues. Completing implementation

of conduct of operations has slipped three times since 2009. Major concerns have been effective use

of procedures and appropriate control of system and equipment status.

The criticality infraction of August 11, 2011, where three limits were violated, is of particular

concern. One operator violated two interaction controls and created an over-mass condition,

recognized by a second operator. As incorrectly advised by the second operator, the first operatorthen restored material to its initial configuration while the second operator began the infraction

notification process. LANS procedures prohibit moving material involved in an infraction until the

configuration has been evaluated for criticality safety.

The organizational response to this infraction is still developing. Management appropriately

critiqued the event and then implemented an operational pause and mandatory training. Response

by many operators and managers indicate they have been over-trained and de-sensitized to the

potential for criticality. They are deeply familiar with the operations but also over-confident in their

assumption that the possibility of a criticality accident in PF-4 is remote.

Given the weaknesses in conduct of operations and configuration management, NNSA isparticularly concerned with the adequacy for a few specific operations with less-than-typical

criticality safety margin. The following operations need immediate increased scrutiny:

Large mass ingot operations in one room Solution operations in specific tanks lacking critical-safe geometry (i.e., less than 6 inches) Bulk acid and recycled acid systems, still lacking engineered back-flow prevention


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Attachment A

Issues/Deliverables Identification Form

WI 06.01, Rev. 2LASO Oversight/SurveillanceIssues Reporting

Use only for UNCLASSIFIED issues and/or deliverables that are also not otherwise controlled

(i.e.: No UCNI, OUO, Privacy Act, etc).

Issue/Deliverable Identifier: Finding

Identifier Name, Phone & Email: Patrick Moss

(505) 665-9233

[email protected]

Issue Tracking number: LASO-WI06.01-TA55-PM-11-02

Issue Identification: Evaluation of Plutonium Backflow Potential Calculation

Date Identified: 09/15/11

Location(TA, bldg, room #) TA-55, PF-4

Subject Area Reviewed Potential backflow of solution into the bulk acid tank

Issues Description SB-CS-06-092 (8/2/06) transmitted to PF-4 management an

issue regarding the potential to backflow fissile solution to

the bulk acid tank located outside the facility. The bulk acidtank is unfriendly geometry and located outside PF-4s

confinement boundary.

CSED-07-028, the Level 3 evaluation for the ion exchange

process, documents a set of administrative controls to

preclude the upset; they include drawing vacuum on the

column prior to initiating transfer and only performing thetransfer of acid when the column is empty.

In October 2009, the PF-4 operating group documented a

calculation showing that up to 27 liters of lean solution and 5

to 10 liters of rich solution could backflow into the bulknitric acid tank. Responsible line management approved the

calculation nearly a year later (September 2010).

If the transfer is initiated while there is solution on the

column there is the potential to backflow up to several liters

of rich solution to the bulk acid tank. In this case, inadvertentcriticality outside the facility confinement boundary could be

achieved.

SB-CS weekly status reports from PF-4 Nuclear CriticalitySafety Board (NCSB) meetings indicate that the calculation

described above was not provided to the NCS group as

requested in work request documentation. It is also unclear


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Attachment A

Issues/Deliverables Identification Form

WI 06.01, Rev. 2LASO Oversight/SurveillanceIssues Reporting

if this information was provided to/reviewed by the LANS

Safety Basis division.

Several violations of requirements are apparent, including

but not necessary limited to the following: Administrative controls have been used for over five

years where engineered features were recommended

by the NCS organization. This is a violation of DOE-O-420.1B, Ch 3. Section 3.a.4.b

The administrative controls selected may not besufficiently independent to preclude a single event

resulting in an inadvertent criticality. DOE-O-

420.1B, Ch 3. Section 3.a.2

The criticality accident alarm system is not designed

to detect an event outside the facility, and emergencyresponse procedures do not address this potential.This is a violation of DOE-O-420.1B, Ch 3. Section

3.e

When the new information was identified in 2009,the facility did not promptly initiate the PISA processas required by 10CFR830.203(d).

Program Affected by Issue Criticality Safety at PF-4

Functional Area Affected Operations

References LANS SD-130

ANS/ANSI 8.1 (as required by DOE-O-420.1B)

sept. 16 letter from nnsa to los alamos national laboratory regarding nuclear safety issues

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