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. . �, .../\ T�� . t.l,\ � 2 1 cooling and electrical supply for pools C & D will have to be met from unit one. He explained the 2 design of the facility and how the plant operates. He mentioned that the water in the pools provides 3 both shielding and cooling for the high levels of radioactivity and that fuel is brought to the site from 4 other reactors operated by CP&L. All nuclear plants in the country have a problem with accumulating � 5 stocks of spent fuel because the Federal government has not yet developed a repository for spent 6 fuel. CP&L intends, by putting into use pools C & D, to provide a capacity at the Shearon Harris Plant 7 to accommodate all of the spent fuel that CP&L produces in all four of its reactors. He explained that 8 there are racks at the base of the pools where the spent fuel is stored. The Harris Plant is a 9 Pressurized Water Reactor(PWR). This is a very long, thin structure made up of many small tubes. I 10 These tubes are made of a zirconium alloy and fuel pellets are placed inside them. He described the 11 design of the Boiling Water Reactor (BWR) and the Pressurized Water Reactor(PWR). He 12 mentioned that as the quantities of spent fuel have accumulated at nuclear piants, the lice,nsees have 13 switched to more compact storage design. They have moved from an open frame design to a closed 14 box design which allows for the storage of more spent fuel. He stated that the closed box design has 15 an important safety implication which he would discuss later in his presentation. He explained the 16 cooling systern design used in nuclear plants. 17 Safetv Issues: Dr. Thompson stated that there were technical issues identified in the License 18 Amendment Application. The design intent of the Shearon Harris Plant was that Unit Two, which was 19 not constructed, would perform the support functions for pools C & D. That is no longer possible. The 20 licensee has calculated that the maximum heat load that will be present in these pools is 15.6 million 21 BTU's per hour. The licensee also has determined that the component cooling water system for unit 22 one cannot accommodate a heat-load of that magnitude. The company's plan for the next several 23 years is to adrninistratively limit the heat-load in pools C & D to one million BTU per hour and to 24 exploit the margin in the existing component cooling water(CCW) systems so as to meet that heat 25 load. This raises what is known as an "Unreviewed Safety Question" because this same system 26 serves safety functions at the reactor. Therefore, the licensee has to demonstrate, and the NRC has 27 to agree that the system has enough capability to meet the additional load of the spent fuel pools and j 28 serve the safety functions of the reactor. The critical point is the ability of the CCW system to serve �� ' 29 the reactor in the event of an accident because of loss of coolant. The company's longer-term plan is 30 to upgr�de the CCW system. That upgrade would presumably accommodate the heat load of 15.6 31 million BTU's per hour. This situation alone is sufficient to challenge the NRC staffs determination of 32 "No Significant Hazard". First, because an "Unreviewed Safety Question" exists and secondly that the 33 license application is for the ability to fill pools C & D with fuel even though there is no design on the 34 table for a cooling system that could accommodate a full load in the pools. Another point is that in 35 pools C & D the racks will not be safe against criticality for fuel that has a low burn-up. Low burn-up 36 fuel has been used for a relatively short time or is relatively high in enrichment. 37 38 Dr. Gordon Thompson stated that there are a variety of ways in which these pools could run dry. It is 39 relatively low probability event but it is an extremely high consequence event. He mentioned that the 40 NRC only focuses on the possibility of pools running dry. They have not considered the risk 41 significance of a partial drainage. This is another matter that challenges the finding of the"No 42 Significant Hazard" determination. He explained how cooling would have to occur if all of the water 43 were lost. For relatively recently discharged fuel the fuel temperature can rise in this event to the 44 point where a fire occurs. If that occurs a substantial fraction of the radioactivity in the pool can be 45 released into the atmosphere. This could become significant in the case of pools C & D at Shearon 46 Harris because the intent is to use them to store relatively older fuel. The question as to whether or 47 not this older fuel can ignite in the event of a loss of cooling is an important one that should be settled 48 through the hearing process. This cannot be dismissed with a "No Significant Hazard" determination. 49 He mentioned that in the case of a pool fire there is volatile material that enters the atmosphere and 50 travels downwind as fine particles, settles on structures and the ground, and irradiates people or 51 enters the food chain or water supply. � 52 � 53 Dr. Thompson further stated that an alternative is to return to the low-density type of rack. When the 54 water is lost with this configuration the water does not heat up to the point where fire is possible. This