Part 21 Report - 1997-241
ACCESSION #: 9703180058
United States
Enrichment Corporation
USEC 2 Democracy Center
United States 6903 Rockledge Drive
Enrichment Corporation Bethesda, MD 20817
James H. Miller Dir: (301) 564-3309
Vice President, Production Fax: (301) 564-3201
March 14, 1997
SERIAL: GDP 97-0036
U.S. Nuclear Regulatory Commission
Attention: Document Control Desk
Washington, D. C. 20555-0001
Paducah Gaseous Diffusion Plant (PGDP)
Docket No. 70-7001
Initial Notification of 10 CFR 21 Report
The purpose of this letter is to provide Initial Notification to
satisfy the requirements of 10 CFR 21.21(d)(3)(i) of a reportable defect
that has been discovered at the Paducah Gaseous Diffusion Plant (PGDP).
The defect is associated with 1 inch product cylinder valve packing
nuts. The valves are manufactured by Hunt Valve Company, Inc., 1913 State
Street, Salem, Ohio, 44460.
Attached is the associated 10 CFR 21 evaluation checklist and a copy
of pertinent problem reports. The Portsmouth Gaseous Diffusion Plant has
also been apprised of this situation.
Any question related to this subject should be directed to Mark
Lombard at (301) 564-3248.
Sincerely,
James H. Miller
Vice President, Production
Attachment
Page 17 of 18
10 CFR PART 21 EVALUATION CHECKLIST
Page 1 of 2
Following questions provide the criteria for evaluation of 10 CFR Part 21
reportability:
A.1 No Yes Has the NRC already been informed of this condition
pursuant to 10 CFR 21 (for example, by a supplier?
A.2 No Yes If yes, has USEC or LMUS been named as a recipient of
the defective item?
A.3 No Yes Has this condition already been reported to NRC in
accordance with procedure UE2-MC-RE1030?
If the answer to Questions A.1 and A.2 are "Yes", or the answer to
Question A.3 is "Yes", the condition need not be reported under 10 CFR
21. Attach objective evidence of notification of the NRC and complete
Part #.
If the answers to Questions A.1, A.2, and A.3 are "No", continue with the
evaluation.
B.1 No Yes Is the identified condition a deviation or failure to
comply associated with a basic component (including
design, analysis, inspection, testing, fabrication,
replacement parts, or consulting services)?
If the answer to Question B.1 is "No", the condition is not reportable
under 10 CFR 21; attach basis for conclusions and proceed to Section E.
If the answer to Question B.1 is "Yes", continue the evaluation.
No Yes If the answer to Question B.1 is "Yes", has the basic
component been delivered to USEC/LMUS and accepted
for use in the plant or an activity (includes USEC-
dedicated commercial grade items)?
If the answer to Question B.2 is "No", the condition is not reportable
under 10 CFR 21; attach basis for conclusions and proceed to Section E.
If the answer to Question B.2 is "Yes", condition is potentially
reportable. Continue with the evaluation.
C. Further, does the activity or basic component contain any of the
following types of conditions? (Deviation means a departure from the
technical requirements included in a procurement document.)
No Yes 1) The installation, use, or operation of a basic
component containing a deviation?
No Yes 2) A condition or circumstance involving a basic
component that could contribute to exceeding a
safety limit as defined in the GDPs Technical
Safety Requirements (TSRs)?
No Yes 3) A failure to comply with any applicable
regulation, order, or certificate issued by the
NRC?
If all of the answers in this section are "No", the condition is not
reportable; attach basis for conclusion and proceed to Section E. If any
answers are "Yes", continue with the evaluation.
Page 18 of 18
Page 2 of 2
Could the deviation or failure to comply create a substantial safety
hazard resulting in any of the following (assume there are no
redundant or back-up system):
No Yes 1) Exposure in exposure in excess of 10 CFR 20.1201
limits
No Yes 2) Exposure of an individual in an unrestricted
area to more than 0.5 rem in one calendar year
(10 CFR 20.1301(c)
No Yes 3) Release of radioactive material to an
unrestricted area in excess of the limits in 10
CFR 20, Appendix B, Table 2
No Yes 4) A deficiency which seriously compromised the
ability of a UF sub [illegible] confinement
system to perform its designated function
No Yes 5) Other (explain)
If all answers in this section are "No", the condition is not reportable;
complete Part E. If any answer is "Yes", condition is reportable.
Continue with evaluation.
E. Evaluation results and recommendation. Recommend condition be
reported?
No Yes If answer is "Yes", sign this part and continue to
follow procedure UE2-EG-GE1039. Sign the evaluation
checklist and forward to the Manager, NRA. If answer
is "No", evaluation is complete. Sign the evaluation
checklist and forward to Commitment Management for
closure of Problem Report.
Attach written summary of evaluation and basis for conclusions.
Investigator
Name Signature Date
[illegible] Reviewer:
Name Signature Date
NRA: Name Signature Date
10 CFR PART 21 EVALUATION CHECKLIST
Page 3 of 3
SUMMARY OF EVALUATION AND BASIS FOR CONCLUSIONS
Cracking of the nuts has been observed and, in one case, resulted in a
reportable release of UF sub 6. Metallurgical analysis of the cracked
nuts has shown stress corrosion cracking to be the degradation mechanism.
Intergrannular cracking has been detected in cylinder valve packing nuts
which have been used in various stages of the enrichment process. In
addition, intergrannular cracking of packing nuts has been detected in
"new" cylinder valves removed from new cylinders to allow receipt
inspections. The removed valves were placed in storage and were not
exposed to plant process chemicals or handling practices affecting the
packing nut. This indicates that the problem is a material or
manufacturing problem with the nuts. Three valve packing nut materials
are currently used; monel, ASTM B150 613 alloy, and CDA 636 alloy. The
cracking problem has been observed only in the 636 alloy nuts on valves
supplied by Hunt Valve Co., Inc..
USEC-651, Rev 7, Uranium Hexafloride, A Manual of Good Handling
Practices, section 5.4.6, discusses past defects in one inch cylinder
valves and the potential adverse effects. One past defect was packing
nuts which have split during service. It is identified that this
condition could allow the stem packing rings to be forcefully ejected
from the valve, resulting in a UF sub 6 release.
Failure of a cylinder valve packing nut and ejection of the valve packing
with an open valve on a full cylinder would constitute a failure of a UF
sub 6 confinement system.
Business Prioritization System Page 1
Problem Report Response Sheet
Response Due: / /
ISSUE TITLE..: SMOKE RELEASED FROM CYLINDER VALVE ON PP-2549
ASSESSMENT...: PROBLEM REPORTS JANUARY - DECEMBER 1997 [UC97A0001]
ISSUE ID.....: UC9710318 MANAGER.......: PENROD SR
FINDING NO...: PR-CO-97-0289 FUNC, ORG.....: 12 - Operations
STATUS.......: CANC GROUP.........: (Unassigned)
TYPE.........: PR-Problem Report
SUB-TYPE.....: NW - Notification ORIGINATING
FUNC. ORG.....: 12-Operations
ORIGINATING
GROUP.........: 793 -UF6 Handling
Shifts
PRIORITY.....: 0 INITIATED BY..: 28539
LOCATION.....: DISCOVERY DATE: 01/19/1997 2200
BUILDING.....: C-310
MAIL STOP....: C-331 PROCEDURE/SPEC./DRAW..:
ROOT CAUSE DETERMINATION
TapRoot Code(s):
FLAGS
DESCRIPTION
UPGRADED TO EVENT REPORT PAD-ER-1997-001
A small wisp of smoke was released from the cylinder valve on
cylinder PP-2549. PGLD YE-75 over the [illegible] withdrawal
position pigtail was actuated. The operators were in the process of
evacuating/purging the pigtail on a full product cylinder. The wisp
was observed after the pigtail was pressured above atmosphere. A
noticeable crack circumvents the packing nut. The operators exited
the area and donned additional PPE. The pigtail was purged using
subatmospheric doubling purges and the cylinder valve confirmed
closed. Cylinder was disconnected with no further incident and
defective valve tag and caution tag was placed on the cylinder. HF
and uranium samples were pulled with negative results. The ARP was
followed and the PSS notified.
ACTIONS TAKEN
NONE
RECOMMENDED ACTIONS
Replace cylinder valve on PP-2549. Analyze failure of valve cap.
PSS JUSTIFICATION/COMMENTS
Urine samples were obtained. UF6 detection safety system was
actuated and operated as designed. 24 hour event report PAD-1997-DD2
issued. Criteria met Appendix E [(a) unusual and Appendix F. J. (2)
24 hour. Small wisp released from cracked packing nut when pigtail
pressured up. HP smears were negative. This PR should be evaluated
for 10CFR21 reportability.
REMARKS
MANAGEMENT RESPONSE
Business Prioritization System Page 1
Problem Report Response Sheet
Response Due: 04/04/1997
ISSUE TITLE..: C-310 RELEASE FROM CYLINDER VALVE PR-591
ASSESSMENT...: PROBLEM REPORTS JANUARY - DECEMBER 1997 [UC97A0001]
ISSUE ID.....: UC97I0699 MANAGER.......: PENROD SR
FINDING NO...: PR-CO-97-0640 FUNC, ORG.....: 12 - Operations
STATUS.......: PART GROUP.........: 070 Operations
Management
TYPE.........: PR-Problem Report
SUB-TYPE.....: (Unassigned) ORIGINATING
FUNC. ORG.....: 12-Operations
ORIGINATING
GROUP.........: 793 -UF6 Handling
Shifts
PRIORITY.....: 0 INITIATED BY..: 13945
LOCATION.....: DISCOVERY DATE: 02/07/1997 0827
BUILDING.....: C-320
MAIL STOP....: C-331 PROCEDURE/SPEC./DRAW..: CP4-CO-072010
Rev. 0
ROOT CAUSE DETERMINATION
TapRoot Code(s):
FLAGS
DESCRIPTION
A small wisp of smoke was released from the cylinder valve on
cylinder PK-591 during purging operations. This activated PGLD YE-73
in the R3 withdraw position ventilation duct. The wisp was observed
after the pigtail was pressured above atmosphere. A noticeable crack
circumvents the packing nut.
ACTIONS TAKEN
Operations immediately exited the area. Alarm was responded to per
procedure. HF samples and wipes were negative. The pigtail was
purged using subatmospheric doubling purges. Cylinder was
disconnected with no further incident.
RECOMMENDED ACTIONS
Replace cylinder valve on PK-591. Investigate failure of packing
nut.
PSS JUSTIFICATION/COMMENTS
24 Hour Event Report per UE2-MC-RE1030, Appendix E criteria 1. I,
unusual (a), and Appendix F criteria J.2. Appropriate response was
made. HF and HP surveys were negative. Precautionary urine samples
were obtained from the two workers who were present.
REMARKS
03/06/97: Per PRSC, assign to Operations for disposition. This PR
will be closed to PR-CO-97-0640 which is a SCAQ.
03/05/97: DOE reportable events due to DOE on/after 03/03/97 (date
NRC assumed regulatory oversight) have been downgraded to problem
reports, PR-CO-97-0640 has been placed back in PART status and will
be taken back to the screening Committee for SCAQ determination,
action plan due date, etc. Event Report PAD-DR-1997-004D (UC9710810)
has been cancelled.
MANAGEMENT RESPONSE
Business Prioritization System Page 1
Problem Report Response Sheet
"31" PROBLEM REPORTS
Response Due: 03/20/1997
ISSUE TITLE..: PACKING NUT ON CYLINDER PP-2520 IN E YARD CRACKED
ASSESSMENT...: PROBLEM REPORTS JANUARY - DECEMBER 1997 [UC97A0001]
ISSUE ID.....: UC9711002 MANAGER.......: BROWN JR
FINDING NO...: PR-SU-97-08588 FUNC, ORG.....: 31 - Engineering
STATUS.......: PART GROUP.........: 814-Mechanical
& Process
TYPE.........: PR-Problem Report
SUB-TYPE.....: (Unassigned) ORIGINATING
FUNC. ORG.....: 38-Production Support
ORIGINATING
GROUP.........: 340 -Process
Technical & NDA
PRIORITY.....: 0 INITIATED BY..: 32454
LOCATION.....: DISCOVERY DATE: 02/18/1997 1445
BUILDING.....: C-765-E
MAIL STOP....: C-710 PROCEDURE/SPEC./DRAW..:
ROOT CAUSE DETERMINATION
TapRoot Code(s):
FLAGS
DESCRIPTION
The packing nut on cylinder PP-2520 in the E yard was found cracked
around the circumference (or approximately the top thread) through
approximately 80% of the section. This is a "Hunt" valve alloy
"6.36" nut. (or #390795-8). This packing nut failure was found while
inspecting Paducah plant cylinders with an eddy current probe for
indications of cracked nuts, but was clearly visible with crack
opening of approximately 1/8". The cylinder appeared to be empty.
ACTIONS TAKEN
NONE
RECOMMENDED ACTIONS
NONE
PSS JUSTIFICATION/COMMENTS
Found during a random sampling of Hunt valves with the "6-36"
packing nut. No sign of any leakage. 10 ton cylinder. Per NMC&A
records, is an empty cylinder with notation requiring a valve
change. This should be evaluated for 10 CFR 21 and 71.95
applicability.
REMARKS
02/20/97: Part A is assigned to Operations and Management response
provided at PRSC. No further action required. Part 5 is assigned to
Engineering to evaluate for 10 CFR applicability.
MANAGEMENT RESPONSE
Name of person providing response:
*** END OF DOCUMENT ***
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