Equipment Failure Procedure

SP-28 Soluble Poison System 10/22/62

A. Failure Of Soluble Poison System During Daily check

NOTE: The conditions in the soluble poison system and operation of the associated equipment are to be checked once a day.

• 1. If the water level is found to be below normal level return it to the proper level in the sight glass with fill water from a demineralized feed.
• 2. IF the tank agitator is malfunctioning or inoperative,tag out the controls, and repair the unit. If soluble poison is required in the reactor while the unit is inoperative us a paddle to dissolve the boric acid crystals.
• 3. IF the operating immersion heater is inoperative, switch to the standby heater, tag out the controls of the inoperable heater, and repair the unit. If soluble poison is required in the reactor, while the inoperative heater is out of service, it will require a longer time to dissolve the boric acid and prepare it for injection in the primary system.
• 4. If both immersion heaters are inoperative, tag out the controls, and repair the units. IF soluble poison is required in the reactor while the inoperative heaters are out of service, drain the water in the tank and fill with hot water from the deaerated feedwater tank. Dissolve 100 pounds of boric acid in the tank and start pumping the tank solution into the reactor. IF the tank temperature drops to 150F, raise the temperature by adding hot water from the DFT. Cautiously add more boric acid crystals. Be sure that all the crystals dissolve. Continue this operation until the boric acid is in the reactor.
• 5. IF the tank is empty during the daily check or below 175F and if the cause cannot be immediately corrected, shut the reactor down and repair the faulty unit.

B. Failure Of Soluble Poison System While Testing It With the Weekly Operational Check Of The Emergency Cooling System

• The soluble poison system is operated in direct association with the emergency cooling system and the operation of the emergency cooling system is checked on a weekly basis, in order to insure that all equipment is ready to operate if needed. During this period a check is made to determine that suction for the emergency makeup pump can be taken from the soluble poison tank. If a failure occurs in either of these two systems, shutdown the reactor and correct the trouble.

C. Filling And Draining The Soluble Poison Tank

• 1. The water in the soluble poison tank will tend to become stagnant and impure after a period of time. Therefore, the water is to be changed on a monthly basis or more often as determined by sample analysis.
• 2. Unlock and open drain valve SP-4V to drain the tank.
• 3. Unlock and slowly open valve SP-1V.
• 4. Allow filling water to flow through the drain line a few moments and close and lock valve SP-4V.
• 5. Continue to add fill water until the water level is at the normal water level in the tank sight glass. Close and lock valve SP-1V.