Information Notice 1990-19, Potential Loss of Effective Volume for Containment Recirculation Spray at PWR Facilities: Difference between revisions
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{{#Wiki_filter:I | {{#Wiki_filter:I | ||
UNITED STATES | |||
NUCLEAR REGULATORY COMMISSION | |||
OFFICE OF NUCLEAR REACTOR REGULATION | |||
LOSS OF EFFECTIVE | WASHINGTON, D.C. 20555 March 14, 1990 | ||
NRC INFORMATION NOTICE NO. 90-19: POTENTIAL LOSS OF EFFECTIVE VOLUME FOR | |||
CONTAINMENT RECIRCULATION SPRAY AT | |||
PWR FACILITIES | |||
==Addressees== | ==Addressees== | ||
: | : | ||
All holders of operating | All holders of operating licenses or construction permits for pressurized water | ||
1 reactors (PWRs). | |||
==Purpose== | ==Purpose== | ||
: This information | : | ||
This information notice is intended to alert addressees to the possible loss of | |||
effective volume for containment recirculation spray caused by the entrapment | |||
of water in the refueling canal of PWRs. It is expected that recipients will | |||
review the information for applicability to their facilities and consider | |||
actions, as appropriate, to avoid similar problems. However, suggestions | |||
contained in this information notice do not constitute NRC requirements; | |||
therefore, no specific action or written response is required. This infor- mation notice resolves and completes action on Generic Safety Issue 95, | |||
*Loss of Effective Volume for Containment Recirculation Spray." | |||
of | ==Description of Circumstances== | ||
: | |||
In 1983, the NRC staff resident inspector at H. B. Robinson Unit 2 questioned | |||
canal | the licensee's practice of leaving the refueling canal drain valve in the | ||
closed position during plant operation. The specific concern was that if | |||
the refueling canal drain valve tina PWR dry containment Is closed during | |||
plant operation and the plant experiences a loss-of-coolant accident (LOCA), | |||
that fraction of the containment spray which falls into the refueling canal | |||
and | would be prevented from returning to the containment emergency sump. Eventu- ally the entire volume of the refueling canal could be filled with water, preventing that amount of water from being available for the post-LOCA re- circulation mode for containment and reactor cooling. | ||
A subsequent investigation by the H. B. Robinson licensee revealed that | |||
Westinghouse had intended the refueling canal drain valve to be open during | |||
operation. However, operation with the valve closed was found to have | |||
negligible safety significance because the maximum volume of water that | |||
could be entrapped in the refueling canal was small relative to the large | |||
volume of water available from the refueling water storage tank. Never- theless, the licensee decided to operate the plant with the valve open | |||
and revise plant procedures accordingly. | |||
accordingly. | |||
9003080213 b | 9003080213 b | ||
I | I | ||
C | |||
the | IN 90-19 March 14, 1990 The staff reviewed the licensee's response and corrective action (operation | ||
with the drain valve open) and found them acceptable. Further, the staff | |||
of this issue. Of particular | considered the potential generic implications of this issue. Of particular | ||
concern was whether there are large spaces that might entrap the recirculation | concern was whether there are large spaces that might entrap the recirculation | ||
water and whether this water can be adequately | water and whether this water can be adequately drained to the containment sump. | ||
drained to the containment | |||
sump. | |||
The staff addresses this concern in the design review under Standard Review | |||
Plan (SRP) Section 6.2.2, 'Containment Heat Removal System." However, there | |||
are PWR plants that were not reviewed under SRP Section 6.2.2 to determine if | |||
the entrapment of containment recirculation water could occur. There are 27 PWR plants licensed before SRP Section 6.2.2 was issued. Other PWR plants were | |||
reviewed under SRP Section 6.2.2, but plant procedures may not have been ex- plicitly evaluated for this safety matter. | |||
Safety Significance: | |||
The principal concern is the potential for the entrapment of containment spray | |||
water in operating PWRs. The concern arises because if a sufficient volume of | |||
spray water is prevented from returning to the containment emergency sump, adequate flow in the containment spray recirculation and emergency core coolant | |||
recirculation mode may not be provided. Insufficient flow to the sump can | |||
spray and | result in inadequate net positive suction head to the containment spray and | ||
pumps. Subsequently, proper post-LOCA | low pressure safety injection pumps. Subsequently, proper post-LOCA contain- ment cooling and reactor core cooling can be disabled. | ||
In the NRC staff's evaluation of Generic Safety Issue 95, the staff concluded | |||
that the safety significance of this issue depends primarily upon whether en- trapment of an unacceptable volume of containment spray water could occur during | |||
of | the recirculation phase. Licensees may wish to review the adequacy of their | ||
procedures for ensuring proper water drainage to the containment emergency sump. | |||
Requiring that the refueling canal drain valves be open while the reactor is | |||
operating or other comparable provisions may be appropriate. In this con- nection, we note that the current plant technical specifications for PWRs | |||
with ice-condenser containments include operability and surveillance require- ments for the refueling canal drain valve during power operation. | |||
This information notice requires no specific action or written response. If | |||
you have any questions about the information in this notice, please contact the | |||
technical contact listed below or the appropriate NRR project manager. | |||
Charles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technical | ===Technical Contact:=== | ||
Chang-Yang Li, NRR | |||
Contact: Chang-Yang | |||
Li, NRR | |||
(301) 492-0875 Attachment: List of Recently Issued NRC Information Notices | |||
.,, I i | |||
Attachment | |||
IN 90-19 March 14, 1990 LIST OF RECENTLY ISSUED | |||
NRC INFORMATION NOTICES | |||
Information Date ot | |||
Notice No. Subject - Issuance Issued-to | |||
90-18 Potential Problems with 3/9/90 All holders of OLs | |||
Crosby Safety Relief Valves or CPs for nuclear | |||
Used on Diesel Generator power reactors. | |||
Air Start Receiver Tanks | |||
90-17 Weight and Center of 3/8/90 All holders of OLs | |||
Gravity Discrepancies or CPs for nuclear | |||
for Copes-Vulcan Valves power reactors. | |||
89-59, . . Suppliers of Potentially 3/7/90 All holders of OLs | |||
Supp. 2 Misrepresented Fasteners or CPs for nuclear | |||
power reactors. | |||
90-16 Compliance with New 3/7/90 All materials licensees. | |||
Decommissioning Rule | |||
of | 90-15 Reciprocity: Notification 3/7/90 All holders of NRC | ||
of Agreement State Radiation materials licenses _._ | |||
Control Directors Be ore which authorize use | |||
Beginning Work in Agreement of radioactive | |||
States material at temporary, Job sites. | |||
90-14 Accidental Disposal of 3/6/90 All U.S. NRC byproduct | |||
Radioactive Materials material licensees. | |||
90-13 Importance of Review and 3/5/90 All holders of OLs | |||
Analysis of Safeguards or CPs for nuclear | |||
Event Logs power reactors. | |||
90-12^ Monitoring or Interruption 2/28/90 All holders of OLs | |||
of Plant Communications or CPs for nuclear | |||
power reactors. | |||
90-11 Maintenance Deficiency 2/28/90 All holders of OLs | |||
Associated with Solenoid- or CPs for nuclear | |||
Operated Valves power reactors. | |||
90-10 Primary Water Stress 2/23/90 All holders of OLs | |||
Corrosion Cracking (PWSCC) or CPs for PWRs. | |||
of Inconel 600 | |||
OL = Operating License | |||
CP = Construction Permit | |||
the | ; ~ IN 90-19 March 14, 1990 The staff reviewed the licensee's response and corrective action (operation | ||
with the drain valve open) and found them acceptable. Further, the staff | |||
of this issue. Of particular | considered the potential generic implications of this issue. Of particular | ||
concern was whether there are large spaces that might entrap the recirculation | concern was whether there are large spaces that might entrap the recirculation | ||
water and whether this water can be adequately | water and whether this water can be adequately drained to the containment sump. | ||
drained to the containment | |||
sump. | |||
The staff addresses this concern in the design review under Standard Review | |||
Plan (SRP) Section 6.2.2, *Containment Heat Removal System." However, there | |||
are PWR plants that were not reviewed under SRP Section 6.2.2 to determine if | |||
the entrapment of containment recirculation water could occur. There are 27 PWR plants licensed before SRP Section 6.2.2 was issued. Other PWR plants were | |||
reviewed under SRP Section 6.2.2, but plant procedures may not have been ex- plicitly evaluated for this safety matter. | |||
Safety Significance: | |||
The principal concern is the potential for the entrapment of containment spray | |||
water in operating PWRs. The concern arises because if a sufficient volume of | |||
spray water is prevented from returning to the containment emergency sump, adequate flow in the containment spray recirculation and emergency core coolant | |||
recirculation mode may not be provided. Insufficient flow to the sump can | |||
result in inadequate net positive suction head to the containment spray and | |||
low pressure safety injection pumps. Subsequently, proper post-LOCA contain- ment cooling and reactor core cooling can be disabled. | |||
In the NRC staff's evaluation of Generic Safety Issue 95, the staff concluded | |||
that the safety significance of this issue depends primarily upon whether en- trapment of an unacceptable volume of containment spray water could occur during | |||
the recirculation phase. Licensees may wish to review the adequacy of their | |||
procedures for ensuring proper water drainage to the containment emergency sump. | |||
canal drain | Requiring that the refueling canal drain valves be open while the reactor is | ||
operating or other comparable provisions may be appropriate. In this con- nection, we note that the current plant technical specifications for PWRs | |||
with ice-condenser containments include operability and surveillance require- ments for the refueling canal drain valve during power operation. | |||
If | This information notice requires no specific action or written response. If | ||
about the information | you have any questions about the information in this notice, please contact the | ||
technical contact listed below or the appropriate NRR project manager. | |||
Charles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technical | ===Technical Contact:=== | ||
Chang-Yang Li, NRR | |||
Contact: Chang-Yang | |||
Li, | |||
(301) 492-0875 $ % \ | |||
Attachment: List of Recently Issued NRC Information NoticesW:2 0-t_ -6 Document Name: INFO NOTICE - KADAMBI, LI | |||
* | I *SEE PREVIOUS CONCURRENCES | ||
*OGCB:DOEA:NRR *SPLB:DST:NRR | |||
h W- | |||
*RPB:ADM *C/OGCB:DOEA:NRR *D/DET:NRR | |||
AThadani | l NPKadambi CYLi TechEd H ?3CBerlinger AThadani I | ||
,^02/26/90 03/07/90 03/02/90 03/7/90 03/7/90 03/4 /90 | |||
kv 3 (* , V | |||
IN 90-XX | |||
action (operation | March xx, 1990 The staff reviewed the licensee's response and corrective action (operation | ||
with the drain valve open) and found them acceptable. | with the drain valve open) and found them acceptable. Further, the staff | ||
considered the potential generic implications of this issue. Of particular | |||
the potential | |||
generic implications | |||
of this issue. Of particular | |||
concern was whether there are large spaces that might entrap the recirculation | concern was whether there are large spaces that might entrap the recirculation | ||
water and whether this water can be adequately | water and whether this water can be adequately drained to the containment | ||
sump. The staff addresses this concern in the design review under Standard | |||
Review Plan (SRP) Section 6.2.2, Containment Heat Removal System." However, there are PWR plants that were not reviewed under SRP Section 6.2.2 to determine | |||
if the entrapment of containment recirculation water could occur. There are 27 PWR plants licensed before SRP Section 6.2.2 was Issued. Other PWR plants were | |||
reviewed under SRP Section 6.2.2, but plant procedures may not have been ex- plicitly evaluated for this safety matter. | |||
of containment | Safety Significance: | ||
The principal concern is the potential for the entrapment of containment spray | |||
water in operating PWRs. The concern arises because if a sufficient volume of | |||
water | spray water is prevented from returning to the containment emergency sump, adequate flow in the containment spray recirculation and emergency core coolant | ||
may not | recirculation mode may not be provided. Insufficient flow to the sump can | ||
result in inadequate net positive suction head to the containment spray and low | |||
pressure safety injection pumps. Subsequently, proper post-LOCA containment | |||
cooling and reactor core cooling can be disabled. | |||
of | In the NRC staff's evaluation of Generic Safety Issue 95, the staff concluded | ||
that the safety significance of this issue depends primarily upon whether | |||
entrapment of an unacceptable volume of containment spray water could occur | |||
during the recirculation phase. In order to resolve this potential safety | |||
problem, licensees may wish to incorporate procedures to ensure proper water | |||
to the containment | drainage to the containment emergency sump, such as requiring that the refuel- ing canal drain valves be open while the reactor is operating or consider other | ||
comparable provisions. In this connection, we note that the current plant | |||
technical specifications for PWRs with ice-condenser containments include | |||
operability and surveillance requirements for the refueling canal drain valve | |||
during power operation. | |||
This information notice requires no specific action or written response. If | |||
you have any questions about the information in this notice, please contact the | |||
technical contact listed below or the appropriate NRR project manager. | |||
Charles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technical | ===Technical Contact:=== | ||
Chang-Yang Li, NRR | |||
Contact: Chang-Yang | |||
Li, | |||
(301) 492-0875 Attachment: List of Recently Issued NRC Information Notices | |||
Document Name: INFO NOTICE - KADAMBI, LI Jel | |||
\"SEE PREVIOUS CONCURRENCES I | |||
*OGCB:DOEA:NRR *SPLB:DST:NRR *RPB:ADM X /OGCB:DOEA:NRR D/D'T:NRR D/DOEA:NRR | |||
,gNPKadambi CYLi TechEd CHBerlinger AThadani CERossi | |||
02/26/90 03/07/90 03/02/90 03/7/90 0317 /90 03/ /90 | |||
IN 90-XX | |||
the | March xx, 1990 The staff reviewed the licensee's response and corrective action (operation | ||
with the drain valve open) and found them acceptable. Further, the staff | |||
of this issue. Of particular | considered the potential generic implications of this issue. Of particular | ||
concern was whether there are large spaces that might entrap the recirculation | concern was whether there are large spaces that might entrap the recirculation | ||
water and whether these spaces can be adequately | water and whether these spaces can be adequately drained to the containment | ||
drained to the containment | |||
sump. The staff addresses this concern in the design review under Standard | |||
Review Plan (SRP) Section 6.2.2, "Containment Heat Removal System." Those PWR | |||
to | plants that were not reviewed under SRP Section 6.2.2 may need to be reviewed | ||
carefully to determine if the entrapment of containment recirculation water | |||
could occur. There are 27 PWR plants licensed before SRP Section 6.2.2 was | |||
issued. Other PWR plants were reviewed under SRP Section 6.2.2, but plant | |||
procedures may not have been explicitly evaluated for this safety matter. | |||
Safety Significance: | |||
The principal concern is the potential for the entrapment of containment spray | |||
water in operating PWRs. The concern arises because if a sufficient volume of | |||
spray water is prevented from returning to the containment emergency sump, adequate flow in the containment spray recirculation and emergency core coolant | |||
flow to the sump can | recirculation mode may not be provided. Insufficient flow to the sump can | ||
net positive suction head to the containment | result in inadequate net positive suction head to the containment spray and low | ||
pressure safety injection pumps. Subsequently proper post-LOCA containment | |||
cooling and reactor core cooling can be disabled. | |||
In the NRC staff's evaluation of Generic Safety Issue 95, the staff concluded | |||
that the safety significance of this issue depends primarily upon whether | |||
entrapment of an unacceptable volume of containment spray water could occur | |||
during the recirculation phase. In order to resolve this potential safety | |||
problem, licensees may wish to incorporate procedures to ensure proper water | |||
drainage to the containment emergency sump, such as requiring that the refuel- ing canal drain valves be open while the reactor is operating or consider other | |||
comparable provisions. In this connection, we note that the current plant | |||
technical specifications for PWRs with ice-condenser containments include | |||
operability and surveillance requirements for the refueling canal drain valve | |||
during power operation. | |||
This information notice requires no specific action or written response. If | |||
you have any questions about the information in this notice, please contact the | |||
technical contact listed below or the appropriate NRR project manager. | |||
Charles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technical | ===Technical Contact:=== | ||
Chang-Yang Li, NRR | |||
Contact: Chang-Yang | |||
Li, | |||
(301) 492-0875 Attachment: List of Recently Issued NRC Information Notices | |||
gfK Document Name: INFO NOTICE - KADAMBI, LI | |||
*SEE PREVIOUS CONCURRENCES | |||
*OGCB:DOEA:NRR SPLB: 51 NRR *RPB:ADM C/OGCB:DOEA:NRR D/DOEA:NRR | |||
NPKadambi CYLi* TechEd CHBerlinger CERossi | |||
02/26/90 03/7 /90 03/02/90 03/ /90 03/ /90 | |||
- IN 90-XX | |||
the | February xx, 1990 The licensee's response and corrective action (operation with the drain valve | ||
open) were reviewed and found acceptable by the staff. Further, the staff | |||
of this issue. Of particular | considered the potential generic implications of this issue. Of particular | ||
concern was whether there are large volumes that might entrap the recirculation | concern was whether there are large volumes that might entrap the recirculation | ||
water and whether these volumes can be adequately | water and whether these volumes can be adequately drained to the containment | ||
drained to the | |||
sump. Because of the lack of specific guidance, those PWR plants that were not | |||
reviewed under SRP Section 6 .2.2 L "Containment Heat Removal System," may need | |||
to be reviewed carefully to determine if entrapment of containment recircula- tion water could occur. There are 27 PWR plants licensed before SRP Section | |||
6.2.2 was issued. Other PWR plants were reviewed under SRP Section 6.2.2 but | |||
may | plant procedures may not have been explicitly evaluated for this safety matter. | ||
Safety Significance: | |||
The principal concern is the potential for containment spray water entrapment | |||
in operating PWRs. The concern arises because if a sufficient volume of spray | |||
emergency | water is prevented from returning to the containment emergency sump, adequate | ||
flow in the containment spray recirculation and emergency core coolant recircu- lation mode may not be provided. This can result in inadequate net positive | |||
suction head to the containment spray and low pressure safety injection pumps | |||
and subsequent inability to provide proper post-LOCA containment and reactor | |||
core cooling. | |||
In the NRC staff's evaluation of Generic Safety Issue 95 the staff concluded | |||
that the safety significance of this issue depends primarily upon whether | |||
entrapment of an unacceptable volume of containment spray water could occur | |||
during the recirculation phase. In order to ameliorate this potential safety | |||
problem, licensees may wish to incorporate procedures to ensure proper water | |||
drainage to the containment emergency sump, such as requiring that the refuel- ing canal drain valve(s) be open while the reactor is operating or consider | |||
other comparable provisions. It is noted that the current plant technical | |||
specifications for PWRs with ice-condenser containments include operability and | |||
surveillance requirements for the refueling canal drain valve during power | |||
operation. | |||
If | This information notice requires no specific action or written response. If | ||
about the information | you have any questions about the information in this notice, please contact the | ||
technical contact listed below or the appropriate NRR project manager. | |||
Charles E. Rossi, Director | |||
Division of Operational Events Assessment | |||
Office of Nuclear Reactor Regulation | Office of Nuclear Reactor Regulation | ||
Technical | ===Technical Contact:=== | ||
Chang-Yang Li, NRR | |||
Contact: Chang-Yang | |||
Li, | |||
(301) 492-0875 Attachment: List of Recently Issued NRC Information Notices | |||
Document Name: INFO NOTICE - KADAMBI, LI | |||
OGCB mOEA:NRR SPLB:DST:NRR R d4;6/OGCB:DOEA:NRR D/DOEA:NRR | |||
CYLi chEd CHBerlinger | NPKadambi CYLi chEd CHBerlinger CERossi | ||
02 /1.b/9 0 02/ /90 f 2-/c2 /90 02/ /90 02/ /90 | |||
3}} | |||
{{Information notice-Nav}} | {{Information notice-Nav}} |
Latest revision as of 04:03, 24 November 2019
I
UNITED STATES
NUCLEAR REGULATORY COMMISSION
OFFICE OF NUCLEAR REACTOR REGULATION
WASHINGTON, D.C. 20555 March 14, 1990
NRC INFORMATION NOTICE NO. 90-19: POTENTIAL LOSS OF EFFECTIVE VOLUME FOR
CONTAINMENT RECIRCULATION SPRAY AT
PWR FACILITIES
Addressees
All holders of operating licenses or construction permits for pressurized water
1 reactors (PWRs).
Purpose
This information notice is intended to alert addressees to the possible loss of
effective volume for containment recirculation spray caused by the entrapment
of water in the refueling canal of PWRs. It is expected that recipients will
review the information for applicability to their facilities and consider
actions, as appropriate, to avoid similar problems. However, suggestions
contained in this information notice do not constitute NRC requirements;
therefore, no specific action or written response is required. This infor- mation notice resolves and completes action on Generic Safety Issue 95,
- Loss of Effective Volume for Containment Recirculation Spray."
Description of Circumstances
In 1983, the NRC staff resident inspector at H. B. Robinson Unit 2 questioned
the licensee's practice of leaving the refueling canal drain valve in the
closed position during plant operation. The specific concern was that if
the refueling canal drain valve tina PWR dry containment Is closed during
plant operation and the plant experiences a loss-of-coolant accident (LOCA),
that fraction of the containment spray which falls into the refueling canal
would be prevented from returning to the containment emergency sump. Eventu- ally the entire volume of the refueling canal could be filled with water, preventing that amount of water from being available for the post-LOCA re- circulation mode for containment and reactor cooling.
A subsequent investigation by the H. B. Robinson licensee revealed that
Westinghouse had intended the refueling canal drain valve to be open during
operation. However, operation with the valve closed was found to have
negligible safety significance because the maximum volume of water that
could be entrapped in the refueling canal was small relative to the large
volume of water available from the refueling water storage tank. Never- theless, the licensee decided to operate the plant with the valve open
and revise plant procedures accordingly.
9003080213 b
I
C
IN 90-19 March 14, 1990 The staff reviewed the licensee's response and corrective action (operation
with the drain valve open) and found them acceptable. Further, the staff
considered the potential generic implications of this issue. Of particular
concern was whether there are large spaces that might entrap the recirculation
water and whether this water can be adequately drained to the containment sump.
The staff addresses this concern in the design review under Standard Review
Plan (SRP) Section 6.2.2, 'Containment Heat Removal System." However, there
are PWR plants that were not reviewed under SRP Section 6.2.2 to determine if
the entrapment of containment recirculation water could occur. There are 27 PWR plants licensed before SRP Section 6.2.2 was issued. Other PWR plants were
reviewed under SRP Section 6.2.2, but plant procedures may not have been ex- plicitly evaluated for this safety matter.
Safety Significance:
The principal concern is the potential for the entrapment of containment spray
water in operating PWRs. The concern arises because if a sufficient volume of
spray water is prevented from returning to the containment emergency sump, adequate flow in the containment spray recirculation and emergency core coolant
recirculation mode may not be provided. Insufficient flow to the sump can
result in inadequate net positive suction head to the containment spray and
low pressure safety injection pumps. Subsequently, proper post-LOCA contain- ment cooling and reactor core cooling can be disabled.
In the NRC staff's evaluation of Generic Safety Issue 95, the staff concluded
that the safety significance of this issue depends primarily upon whether en- trapment of an unacceptable volume of containment spray water could occur during
the recirculation phase. Licensees may wish to review the adequacy of their
procedures for ensuring proper water drainage to the containment emergency sump.
Requiring that the refueling canal drain valves be open while the reactor is
operating or other comparable provisions may be appropriate. In this con- nection, we note that the current plant technical specifications for PWRs
with ice-condenser containments include operability and surveillance require- ments for the refueling canal drain valve during power operation.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact the
technical contact listed below or the appropriate NRR project manager.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact:
Chang-Yang Li, NRR
(301) 492-0875 Attachment: List of Recently Issued NRC Information Notices
.,, I i
Attachment
IN 90-19 March 14, 1990 LIST OF RECENTLY ISSUED
NRC INFORMATION NOTICES
Information Date ot
Notice No. Subject - Issuance Issued-to
90-18 Potential Problems with 3/9/90 All holders of OLs
Crosby Safety Relief Valves or CPs for nuclear
Used on Diesel Generator power reactors.
Air Start Receiver Tanks
90-17 Weight and Center of 3/8/90 All holders of OLs
Gravity Discrepancies or CPs for nuclear
for Copes-Vulcan Valves power reactors.
89-59, . . Suppliers of Potentially 3/7/90 All holders of OLs
Supp. 2 Misrepresented Fasteners or CPs for nuclear
power reactors.
90-16 Compliance with New 3/7/90 All materials licensees.
Decommissioning Rule
90-15 Reciprocity: Notification 3/7/90 All holders of NRC
of Agreement State Radiation materials licenses _._
Control Directors Be ore which authorize use
Beginning Work in Agreement of radioactive
States material at temporary, Job sites.
90-14 Accidental Disposal of 3/6/90 All U.S. NRC byproduct
Radioactive Materials material licensees.
90-13 Importance of Review and 3/5/90 All holders of OLs
Analysis of Safeguards or CPs for nuclear
Event Logs power reactors.
90-12^ Monitoring or Interruption 2/28/90 All holders of OLs
of Plant Communications or CPs for nuclear
power reactors.
90-11 Maintenance Deficiency 2/28/90 All holders of OLs
Associated with Solenoid- or CPs for nuclear
Operated Valves power reactors.
90-10 Primary Water Stress 2/23/90 All holders of OLs
Corrosion Cracking (PWSCC) or CPs for PWRs.
of Inconel 600
OL = Operating License
CP = Construction Permit
- ~ IN 90-19 March 14, 1990 The staff reviewed the licensee's response and corrective action (operation
with the drain valve open) and found them acceptable. Further, the staff
considered the potential generic implications of this issue. Of particular
concern was whether there are large spaces that might entrap the recirculation
water and whether this water can be adequately drained to the containment sump.
The staff addresses this concern in the design review under Standard Review
Plan (SRP) Section 6.2.2, *Containment Heat Removal System." However, there
are PWR plants that were not reviewed under SRP Section 6.2.2 to determine if
the entrapment of containment recirculation water could occur. There are 27 PWR plants licensed before SRP Section 6.2.2 was issued. Other PWR plants were
reviewed under SRP Section 6.2.2, but plant procedures may not have been ex- plicitly evaluated for this safety matter.
Safety Significance:
The principal concern is the potential for the entrapment of containment spray
water in operating PWRs. The concern arises because if a sufficient volume of
spray water is prevented from returning to the containment emergency sump, adequate flow in the containment spray recirculation and emergency core coolant
recirculation mode may not be provided. Insufficient flow to the sump can
result in inadequate net positive suction head to the containment spray and
low pressure safety injection pumps. Subsequently, proper post-LOCA contain- ment cooling and reactor core cooling can be disabled.
In the NRC staff's evaluation of Generic Safety Issue 95, the staff concluded
that the safety significance of this issue depends primarily upon whether en- trapment of an unacceptable volume of containment spray water could occur during
the recirculation phase. Licensees may wish to review the adequacy of their
procedures for ensuring proper water drainage to the containment emergency sump.
Requiring that the refueling canal drain valves be open while the reactor is
operating or other comparable provisions may be appropriate. In this con- nection, we note that the current plant technical specifications for PWRs
with ice-condenser containments include operability and surveillance require- ments for the refueling canal drain valve during power operation.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact the
technical contact listed below or the appropriate NRR project manager.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact:
Chang-Yang Li, NRR
(301) 492-0875 $ % \
Attachment: List of Recently Issued NRC Information NoticesW:2 0-t_ -6 Document Name: INFO NOTICE - KADAMBI, LI
I *SEE PREVIOUS CONCURRENCES
- OGCB:DOEA:NRR *SPLB:DST:NRR
h W-
- RPB:ADM *C/OGCB:DOEA:NRR *D/DET:NRR
l NPKadambi CYLi TechEd H ?3CBerlinger AThadani I
,^02/26/90 03/07/90 03/02/90 03/7/90 03/7/90 03/4 /90
kv 3 (* , V
IN 90-XX
March xx, 1990 The staff reviewed the licensee's response and corrective action (operation
with the drain valve open) and found them acceptable. Further, the staff
considered the potential generic implications of this issue. Of particular
concern was whether there are large spaces that might entrap the recirculation
water and whether this water can be adequately drained to the containment
sump. The staff addresses this concern in the design review under Standard
Review Plan (SRP) Section 6.2.2, Containment Heat Removal System." However, there are PWR plants that were not reviewed under SRP Section 6.2.2 to determine
if the entrapment of containment recirculation water could occur. There are 27 PWR plants licensed before SRP Section 6.2.2 was Issued. Other PWR plants were
reviewed under SRP Section 6.2.2, but plant procedures may not have been ex- plicitly evaluated for this safety matter.
Safety Significance:
The principal concern is the potential for the entrapment of containment spray
water in operating PWRs. The concern arises because if a sufficient volume of
spray water is prevented from returning to the containment emergency sump, adequate flow in the containment spray recirculation and emergency core coolant
recirculation mode may not be provided. Insufficient flow to the sump can
result in inadequate net positive suction head to the containment spray and low
pressure safety injection pumps. Subsequently, proper post-LOCA containment
cooling and reactor core cooling can be disabled.
In the NRC staff's evaluation of Generic Safety Issue 95, the staff concluded
that the safety significance of this issue depends primarily upon whether
entrapment of an unacceptable volume of containment spray water could occur
during the recirculation phase. In order to resolve this potential safety
problem, licensees may wish to incorporate procedures to ensure proper water
drainage to the containment emergency sump, such as requiring that the refuel- ing canal drain valves be open while the reactor is operating or consider other
comparable provisions. In this connection, we note that the current plant
technical specifications for PWRs with ice-condenser containments include
operability and surveillance requirements for the refueling canal drain valve
during power operation.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact the
technical contact listed below or the appropriate NRR project manager.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact:
Chang-Yang Li, NRR
(301) 492-0875 Attachment: List of Recently Issued NRC Information Notices
Document Name: INFO NOTICE - KADAMBI, LI Jel
\"SEE PREVIOUS CONCURRENCES I
- OGCB:DOEA:NRR *SPLB:DST:NRR *RPB:ADM X /OGCB:DOEA:NRR D/D'T:NRR D/DOEA:NRR
,gNPKadambi CYLi TechEd CHBerlinger AThadani CERossi
02/26/90 03/07/90 03/02/90 03/7/90 0317 /90 03/ /90
IN 90-XX
March xx, 1990 The staff reviewed the licensee's response and corrective action (operation
with the drain valve open) and found them acceptable. Further, the staff
considered the potential generic implications of this issue. Of particular
concern was whether there are large spaces that might entrap the recirculation
water and whether these spaces can be adequately drained to the containment
sump. The staff addresses this concern in the design review under Standard
Review Plan (SRP) Section 6.2.2, "Containment Heat Removal System." Those PWR
plants that were not reviewed under SRP Section 6.2.2 may need to be reviewed
carefully to determine if the entrapment of containment recirculation water
could occur. There are 27 PWR plants licensed before SRP Section 6.2.2 was
issued. Other PWR plants were reviewed under SRP Section 6.2.2, but plant
procedures may not have been explicitly evaluated for this safety matter.
Safety Significance:
The principal concern is the potential for the entrapment of containment spray
water in operating PWRs. The concern arises because if a sufficient volume of
spray water is prevented from returning to the containment emergency sump, adequate flow in the containment spray recirculation and emergency core coolant
recirculation mode may not be provided. Insufficient flow to the sump can
result in inadequate net positive suction head to the containment spray and low
pressure safety injection pumps. Subsequently proper post-LOCA containment
cooling and reactor core cooling can be disabled.
In the NRC staff's evaluation of Generic Safety Issue 95, the staff concluded
that the safety significance of this issue depends primarily upon whether
entrapment of an unacceptable volume of containment spray water could occur
during the recirculation phase. In order to resolve this potential safety
problem, licensees may wish to incorporate procedures to ensure proper water
drainage to the containment emergency sump, such as requiring that the refuel- ing canal drain valves be open while the reactor is operating or consider other
comparable provisions. In this connection, we note that the current plant
technical specifications for PWRs with ice-condenser containments include
operability and surveillance requirements for the refueling canal drain valve
during power operation.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact the
technical contact listed below or the appropriate NRR project manager.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact:
Chang-Yang Li, NRR
(301) 492-0875 Attachment: List of Recently Issued NRC Information Notices
gfK Document Name: INFO NOTICE - KADAMBI, LI
- SEE PREVIOUS CONCURRENCES
- OGCB:DOEA:NRR SPLB: 51 NRR *RPB:ADM C/OGCB:DOEA:NRR D/DOEA:NRR
NPKadambi CYLi* TechEd CHBerlinger CERossi
02/26/90 03/7 /90 03/02/90 03/ /90 03/ /90
- IN 90-XX
February xx, 1990 The licensee's response and corrective action (operation with the drain valve
open) were reviewed and found acceptable by the staff. Further, the staff
considered the potential generic implications of this issue. Of particular
concern was whether there are large volumes that might entrap the recirculation
water and whether these volumes can be adequately drained to the containment
sump. Because of the lack of specific guidance, those PWR plants that were not
reviewed under SRP Section 6 .2.2 L "Containment Heat Removal System," may need
to be reviewed carefully to determine if entrapment of containment recircula- tion water could occur. There are 27 PWR plants licensed before SRP Section
6.2.2 was issued. Other PWR plants were reviewed under SRP Section 6.2.2 but
plant procedures may not have been explicitly evaluated for this safety matter.
Safety Significance:
The principal concern is the potential for containment spray water entrapment
in operating PWRs. The concern arises because if a sufficient volume of spray
water is prevented from returning to the containment emergency sump, adequate
flow in the containment spray recirculation and emergency core coolant recircu- lation mode may not be provided. This can result in inadequate net positive
suction head to the containment spray and low pressure safety injection pumps
and subsequent inability to provide proper post-LOCA containment and reactor
core cooling.
In the NRC staff's evaluation of Generic Safety Issue 95 the staff concluded
that the safety significance of this issue depends primarily upon whether
entrapment of an unacceptable volume of containment spray water could occur
during the recirculation phase. In order to ameliorate this potential safety
problem, licensees may wish to incorporate procedures to ensure proper water
drainage to the containment emergency sump, such as requiring that the refuel- ing canal drain valve(s) be open while the reactor is operating or consider
other comparable provisions. It is noted that the current plant technical
specifications for PWRs with ice-condenser containments include operability and
surveillance requirements for the refueling canal drain valve during power
operation.
This information notice requires no specific action or written response. If
you have any questions about the information in this notice, please contact the
technical contact listed below or the appropriate NRR project manager.
Charles E. Rossi, Director
Division of Operational Events Assessment
Office of Nuclear Reactor Regulation
Technical Contact:
Chang-Yang Li, NRR
(301) 492-0875 Attachment: List of Recently Issued NRC Information Notices
Document Name: INFO NOTICE - KADAMBI, LI
OGCB mOEA:NRR SPLB:DST:NRR R d4;6/OGCB:DOEA:NRR D/DOEA:NRR
NPKadambi CYLi chEd CHBerlinger CERossi
02 /1.b/9 0 02/ /90 f 2-/c2 /90 02/ /90 02/ /90
3