United States Nuclear Regulatory Commission - Protecting People and the Environment

Information Notice No. 93-53: Effect of Hurricane Andrew on Turkey Point Nuclear Generating Station and Lessons Learned

                                 UNITED STATES
                         NUCLEAR REGULATORY COMMISSION
                     OFFICE OF NUCLEAR REACTOR REGULATION
                             WASHINGTON D.C. 20555

                                 July 20, 1993


NRC INFORMATION NOTICE 93-53:  EFFECT OF HURRICANE ANDREW ON TURKEY POINT 
                               NUCLEAR GENERATING STATION AND LESSONS LEARNED


Addressees

All holders of operating licenses or construction permits for nuclear power
reactors.

Purpose

The U.S. Nuclear Regulatory Commission (NRC) is issuing this information
notice to alert addressees to the lessons learned from the joint NRC/industry
team review of the effect of Hurricane Andrew on Turkey Point Nuclear
Generating Station.  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 are not NRC requirements; therefore, no specific
action or written response is required. 

Description of Circumstances

Turkey Point, situated on the shores of Biscayne Bay about 40 kilometers  
(25 miles) south of Miami, Florida, is the site for four electric generation
units.  Units 1 and 2 are fossil fuel fired and Units 3 and 4 are pressurized
light water moderated nuclear units that are owned and operated by the Florida
Power and Light Company.  The area experiences tropical storms about once
every 2 years and hurricane-force winds once every 7 years.  

On August 24, 1992, Category 4 (on a scale of 1 to 5, where 5 is the most
severe) Hurricane Andrew hit south Florida and caused extensive onsite and
offsite damage at Turkey Point.  An NRC/industry team was organized to review
the damage that the hurricane caused the nuclear units and the utility actions
to prepare for the storm and recover from it, and to compile lessons that
might benefit other nuclear reactor facilities.  Results of the team review
are presented in the report, "Effect of Hurricane Andrew on the Turkey Point
Nuclear Generating Station from August 20-30, 1992," issued in March 1993. 
This report was distributed to all power reactor licensees by the Institute of
Nuclear Power Operations on June 10, 1993.  

Discussion

Hurricane Andrew is historic because this is the first time that a hurricane
significantly affected a commercial nuclear power plant.  The eye of the  


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storm, with sustained winds of up to 233 kilometers per hour (km/h) [145 miles
per hour (mph)] and gusts of 282 km/h (175 mph), passed over the Turkey Point
site and caused extensive onsite and offsite damage.  

The onsite damage included loss of all offsite power for more than 5 days,
complete loss of communication systems, closing of the access road, and damage
to the fire protection and security systems and warehouse facilities. 
However, despite the intensity of the hurricane and the age of the plant,
onsite damage was limited to fire protection, security, and several non-
safety-related systems and structures.  There was no damage to the safety-
related systems except for minor water intrusion and some damage to insulation
and paint, and there was no radioactive release to the environment.  The units
remained in a stable condition and functioned as designed.  

Lessons Reinforced and Lessons Learned

The joint team report describes circumstances that existed at the Turkey Point
site during and immediately following the hurricane and identifies several
lessons reinforced and learned from the effect of Hurricane Andrew on the
nuclear units.  The issues and lessons are summarized below: 

(1)   Adequacy of Timing of Plant Shutdown in Anticipation of a Hurricane 

      Turkey Point procedures for timing of a plant shutdown in anticipation
      of a hurricane require that the plant be in at least Mode 4 (i.e., hot
      shutdown) 2 hours before the onset of hurricane-force winds at the site.
      Estimating 8 hours to complete an orderly shutdown, the licensee began a
      plant shutdown approximately 12 hours before the predicted landfall of
      the hurricane.  As a result, both units were in Mode 4 when Hurricane
      Andrew struck.  However, the licensee commitments in response to the
      station blackout rule only require the licensee to commence shutdown at
      least 2 hours before the onset of hurricane-force winds.  Therefore,
      starting a plant shutdown strictly in accordance with the licensee
      commitments could have resulted in the plant being in the midst of a
      dual-unit shutdown when offsite power was lost.  Additionally, at Turkey
      Point (and at other commercial reactors susceptible to hurricane
      damage), important equipment (e.g., auxiliary feedwater) is located
      outside and likely would not be accessible during a hurricane.  

(2)   Adequacy of Licensee Offsite Communications for Natural Disasters 

      Although diverse and redundant communications equipment existed at
      Turkey Point, offsite communications were lost during the storm because
      of a common vulnerability to wind damage.  Normal telephone service
      failed because the storm blew down the lines near the station.  The
      dedicated commercial telephone lines servicing the control room,
      technical support center, and emergency operations facility, used to
      give initial notification and status to the State in an emergency, also 

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      failed.  The Federal Telecommunications System (FTS)-2000 lines used for
      the Emergency Notification System failed, cutting off normal
      communications with the NRC Operations Center.  The cellular telephone 
      systems also did not function because the storm damaged the onsite
      antennas and the offsite repeating stations.  Except for one hand-held
      radio on the company FM radio system, the plant radio systems did not
      function during and immediately following the storm.  Overall, all
      offsite communications were lost for about 4 hours during the storm, and
      reliable communications were not restored for about 24 hours following
      the storm.  A temporary satellite communications system provided by the
      NRC aided recovery efforts considerably and would have been more
      beneficial if it had been on site before the storm. 
 
(3)   Adequacy of Compensatory Measures for Equipment or Facilities Not
      Designed for a Hurricane

      A number of important systems, structures, or facilities for security,
      emergency response, effluent monitoring and disposal, and low-level
      waste storage were not designed for hurricane-force winds and were or
      could have been severely damaged during the storm.  In anticipation that
      equipment or facilities could become inoperable, compensatory measures
      were taken or were available before or after the storm.  For example,
      after the storm, security officers were placed on roving patrols to
      compensate for the loss of the physical integrity of the protected area.
      Portable air-sampling and dosimetry equipment was available at the site
      to compensate for the air-sampling stations that were lost.  Before the
      storm, radioactive materials, including dry active waste, were secured
      in SeaLand containers, and a high-integrity container was used for
      solidified resins.  Thus, radioactive waste was adequately protected
      from the elements to prevent its spread during the storm.  The emergency
      plan considered these circumstances and contained contingency measures. 
      However, because of damage to the plant stack and associated ductwork
      and monitoring equipment, a major radiological release path could not
      have been monitored if it had been necessary to do so.  

(4)   Early Preparations for Hurricane 

      Turkey Point benefited greatly from prior hurricane experience of the
      plant staff and extensive planning done in preparing and implementing
      the Emergency Plan Implementing Procedure (EPIP), "Natural Emergencies."
      The EPIP was also significantly expanded as a result of the insights
      gained in part from the individual plant examination (IPE) for
      Turkey Point.  These additional procedures, which dealt with preparation
      for a Category 5 hurricane, contributed significantly to the licensee
      preparations.  A copy of the Turkey Point EPIP is provided in Appendix R
      of the joint team report.  Using the control room simulator to train
      operators immediately before the storm enabled the operators to be more
      alert to any likely plant transients.  


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      After the hurricane, the licensee had to take numerous extraordinary
      actions to establish a support services infrastructure (e.g., housing,
      food, water, and transportation) that would allow the staff to report to
      the plant each day.  Such requirements could be more extreme following
      other external events (e.g., severe earthquake) for which there was no
      warning to permit advance preparations, including the evacuation of
      families of plant personnel.  The assistance provided by personnel at
      the St. Lucie plant in meeting the immediate and longer term needs at
      Turkey Point, such as personnel, spare parts, and supplies, was very
      helpful to the recovery.  

(5)   Impact of Nonsafety Equipment on Important Equipment

      During the storm, failed nonsafety-grade equipment damaged certain
      important equipment.  For example, the high water tank collapsed onto
      the fire water system, rendering the fire protection system inoperable. 
      In addition, the storm threatened safety-related equipment (e.g.,
      potential collapse of the damaged Unit 1 chimney onto the diesel
      generator building).  

Unlike some other natural disasters, onset of a hurricane is predictable and,
as a result, lends itself to adequate early preparations for minimizing its
effect on a facility.  The Turkey Point experience indicates that existing
plant procedures and other additional measures contemplated in response to
hurricanes may not be fully responsive to the challenges posed by a storm of
the magnitude of hurricane Andrew.  On the basis of the experience with
Hurricane Andrew at Turkey Point, the NRC staff is considering the need for
additional regulatory actions. 

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 Office of Nuclear
Reactor Regulation project manager.  


                                    /s/'d by BKGrimes


                                   Brian K. Grimes, Director
                                   Division of Operating Reactor Support
                                   Office of Nuclear Reactor Regulation


Technical contact:  F. Hebdon, NRR
                    (301) 504-2024

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