ML16054A423
| ML16054A423 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 01/26/2016 |
| From: | Northern States Power Co, Xcel Energy |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML16054A376 | List:
|
| References | |
| L-MT-16-004 | |
| Download: ML16054A423 (28) | |
Text
SECTION 9
SECTION 99.1
9.29.2.19.2.2
9.2.3 SECTION
99.39.3.1
9.3.2
9.3.3 Revision
25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 1 of 6SECTION 9PLANT RADIOACTIVE WASTE CONTROL SYSTEMS I/mab9.4Solid Radwaste System9.4.1Design BasisThe solid radwaste system is designed to process, package, store, monitor, and provide shielded storage facilities for solid wastes to allow for radioactive decayand/or temporary storage prior to shipment from the plant for off-site disposal.The solid radioactive wastes are shipped off-site in vehicles equipped with adequate shielding to comply with Department of Transportation (DOT)
regulations.
The design bases of the solid radwaste system are to:a.Minimize radiation exposure to plant operating personnel.
b.Prevent spillage and contamination spread of radioactive materials.
c.Provide safe and reliable means for handling the solid wastes.9.4.2Description9.4.2.1Sources The following are radioactive solids wastes generated in the operation of the plant:a.Process Wastes - filter sludge and spent resins from the liquid processing systems.b.Reactor System Wastes - spent control rod blades, temporary control curtains, fuel channels, and in-core ion chambers.c.Maintenance Wastes - contaminated clothing, tools, rags and small pieces of equipment which cannot be economically decontaminated.d.Operating Wastes - laundry cartridge filters, paper, rags, off-gas filters, and ventilation filters.e.Miscellaneous Wastes - solidified chemical and liquid wastes.
Major flow paths and equipment for the radwaste solids handling system and waste solidification system are shown in Drawings NH-36047 and NH-36047-2,Section 15, respectively.9.4.2.2Processing and Handling Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 2 of 6 I/mab9.4.2.2.1Chemical, Liquid and Process WastesChemical and Liquid Wastes Chemical and liquid wastes which require solidification are added to containersand solidified using special procedures as necessary. The radiation level of
these wastes is low enough to allow this operation to be done by contact
handling in a well-ventilated area. After solidification, the wastes are sealed
and placed in temporary storage for shipment along with the maintenance and operating wastes. Chemical and liquid wastes may also be used to maintain required moisture levels during the solidification of process wastes.Process Wastes
The process wastes are the largest volume of solid wastes processed in the solid radwaste system. The process wastes consist of the filter sludge from the reactor clean-up, fuel pool, and condensate filter/demineralizer systems and the radwaste filters and the spent resins from the radwaste mixed-bed demineralizer. The filter sludge and spent resins are backwashed into their
respective receiving tank, dewatered and processed in the waste solidification
system. An initial dewatering step is accomplished on the condensate and clean-up sludge by sedimentation and decantation. This serves the two-fold purpose of providing decay storage of the sludge in the tanks and reduces the
processing load on the centrifuges.Two centrifuges and two drum-filling systems ("A" system and "B" system) are provided to allow for segregation of the high level and low level sludge in the drumming step. The "B" system includes the waste solidification system (seeSection 9.4.2.2.2), and may also be used for processing sludge for solidification by an outside contractor. The "A" system is a standby system which may be
used for de-watered sludge processing. The sludge are dewatered in the
centrifuge and the moist solids fall directly into surge hoppers located beneath the centrifuges. The hoppers provide surge since only one 55 gal drum may be filled at a time. Empty drums are loaded onto a remotely operated conveyor
system which carries one drum at a time to a selected filling station beneath a hopper. The drum is filled under visual observation and then transferred to a
pre-selected storage conveyor as dictated by the radiation level of the drum contents. All operations in the handling of the process wastes, from the backwashing to the final load-out of the drums, are accomplished by remote
means.
Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 3 of 6 I/mab9.4.2.2.2Waste Solidification System The waste solidification system is part of the "B" hopper system and renders radioactive wastes into a homogeneous, solid product suitable for
transportation and subsequent disposal. The system mixes moist radioactive wastes with dry portland cement and feeds the resulting mixture into standard 55-gallon drums. The system is remotely operated and fully automated to minimize radiation exposure to personnel and to minimize operator error. The
system can also be manually operated. The control panel is located at elevation 935 in the radwaste conveyor operating galley.The solidification system was manufactured by Atcor, Inc., and consists of three basic subsystems:a.waste conditioning and metering,b.dry cement storage and metering, andc.product mixing and package filling.
The waste conditioning sub-system receives processed solid wastes from the centrifuge, adjusts the moisture content to assure a proper cement mixture, and meters the conditioned waste into the mixer/feeder unit for subsequent
mixing with cement.
Dry cement is stored in a 75 cubic foot capacity bin from which it is fed to the mixer/feeder through a combination of two screw feeders. The combined
waste product and dry cement are introduced to the mixer/feeder simultaneously. A screw flight and paddle arrangement within the mixer/feeder insures a thorough mixing action. After completion of the filling operation, the full drum is conveyed to the capping station and storage areas.
A solid radwaste drum decontamination station provides remote control washing of the drums after they are filled and capped so that radiation
exposure to personnel during this operation can be eliminated. The solid
radwaste drums are placed in temporary storage prior to shipment for disposal.
Portable equipment owned and operated by independent contractors has also been used at Monticello for the solidification of process and miscellaneous wastes. This equipment and its associated concrete solidification process is
similar to that provided by Monticello in-plant equipment.
The interface connections from the plants process waste system to the independent contractors portable equipment consists of a waste hose from the
radwaste system, a vent hose from the liner back to the radwaste building ventilation system, electrical, air and demineralized water for the process wasteprocessing unit. A sketch of the system is shown in Figure 9.4-3. Alarms are provided to annunciate high sludge levels in the liner. Transfer hoses are Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 4 of 6 I/mableak-tested prior to use. The waste in the phase separators tanks is normallytransferred to the processing liner in basically the same way as the ATCORsystem. Waste is centrifuged to "B" hopper where liquid has been added,mixed and then pumped to the vendor's liner. Solidification is then conducted
in a liner contained inside a shield cask or a shipping cask.
The solidification system mixes separate feeds of radioactive wastes and dryPortland cement in the liner. Normal operation of the system includes transfer of dry cement from a cement storage bin or from a bulk cement truck into thewaste container. The waste from the plant's waste storage tank is pumped to the shipping container by the plant's permanently installed pumps. After the
correct metered amount has been transferred, the waste flow is stopped and
the correct amount of additives is added to pre-condition the waste. Dry Portland cement is transferred to the liner with a pneumatic transfer system.
Mixing of the waste with the additives and the cement is accomplished by a
disposable agitator pre-mounted in the liner which is driven by a hydraulic motor. Instrumentation is available to monitor the level of waste and cement
level in the liner and the temperature of the cement billet during solidification.Prior to transferring the waste to the liner, a Process Control Program (PCP) is used to verify solidification and to determine the quantities of additives and
cement required. In this procedure a sample of the waste is obtained and
processed to ensure that a solidified product can be obtained.
The primary method for handling solid radwaste is to bypass the B-centrifuge and B-hopper via the bypass line. This method sends solid radwaste directly from the radwaste holding tanks to the waste dewatering system, the
RDS-1000.The RDS-1000, manufactured by Chem-Nuclear Systems, Incorporated (CNSI), is a waste processing system installed for use at the Monticello plant.
This system is a waste dewatering system with connections to the plant systems via the bypass line as noted above. A water return line to the
radwaste drains is used to route extracted liquid back to the plant for
processing. A topical report for the waste dewatering system has been
reviewed by the NRC. The NRC found this system and its operating procedures to be an acceptable process for the preparation of waste for burialto meet the requirements of 10CFR61 (Reference 13). Major flow paths and equipment are shown in Drawing NH-119062, USAR Section 15.9.4.2.3Storage and Shipment for Disposal A radwaste storage building (32 x 80.5) is provided for the solid radwaste truck loading area. This sheet metal building is provided with shield walls, floor
drains, heating and fire protection systems. An overhead crane (capacity of 10
tons) is located in the building. The building is designed to enclose the
radwaste shipping truck and to facilitate loading of the truck.
In addition to normal pendant controls, the overhead crane is radio controlled to enable the crane operator to select the best location to handle the waste and
minimize his radiation exposure.
Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 5 of 6 I/mabA radwaste shipping building is erected along the west side of the radwaste storage building. The building is a metal, steel framed building 25-6 x 127.The waste is packaged, stored and shipped in accordance with applicable DOT
and NRC regulations. All activities are performed in accordance with a Process Control Program and are under the control of the plant staff.9.4.2.3.1Hardware and Other Wastes Not Requiring Solidification Reactor mechanical wastes are stored for decay in the spent fuel storage pool
and subsequently packaged in suitable approved shipping containers for shipment to an approved off-site disposal site. Maintenance and operating
wastes are collected in containers located in appropriate zones in the plant, as dictated by volume and degree of contaminated wastes. The activity level of these wastes is generally low enough to permit contact handling. After the
containers are filled at their respective collection point, the waste is transferred to the Radwaste Building where it is either prepared for shipping off-site to a
processing and/or disposal facility or compacted into drums by a hydraulic press bailing machine. If compacted, ventilation is provided to maintain control of contamination spread during the compacting and packaging operations. The
compacted waste drums are then sealed and placed in temporary storage
along with the non-compressible wastes until final shipment to the burial site.
Other equipment which is too large to be handled in this way requires special procedures. Since the need for handling of large equipment is quite infrequent, providing storage facilities in advance is not justified. Handling of such
equipment depends upon the radiation level, transportation facilities, and
available storage sites. Procedures for decontamination, shielding, shipment,monitoring and storage of such items are developed as necessary.9.4.2.4Process Control Program All activities are performed in accordance with a Process Control Program (PCP) and are under the control of the plant staff. Waste classification andwaste form requirements of 10CFR Part 61 are ensured by the PCP. The
Process Control Program was approved by the NRC in a letter dated February 8, 1983 (Reference 10). A description of changes to the PCP are submitted to the NRC with the Annual Radioactive Effluent Release Report.9.4.3Performance Analysis Radiation exposure to plant operating personnel is minimized by shielding around the sludge collection tanks, centrifuges, drum filling systems, drum storage conveyors and temporary storage areas. Methods are provided for
gross decontamination of equipment which may require periodic maintenance.01103927 Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 6 of 6 I/mabThe majority of the radioactivity released from the reactor process system is collected and retained on the filter sludge and spent resins. Following the dewatering step, the wastes are rendered relatively immobile and the potential for release is reduced. During solidification, radiation level detection is provided to preclude exceeding the curie limits of the transportation container. System
interlocks are provided to prevent spills and improper operation. A loss of power
de-energizes all equipment. Building ventilation is provided to reduce contamination spread with the building ventilation air being filtered through high-efficiency filters prior to discharge via the monitored Reactor Building vents.
The release of activity from the solid radwaste system to the environs is extremely low.
SECTION 99.5
Revision 22 USAR 9.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 1 of 2SECTION 9PLANT RADIOACTIVE WASTE CONTROL SYSTEMS I/jmr FIGURESFOR ADMINISTRATIVE USE ONLYResp Supv:CNSTP Assoc Ref:
SR:2yrs N Freq: USAR-MANARMS:USAR-9.FIGURESDoc Type:Admin Initials:Date:
9703 Revision 22 USAR 9.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 2 of 2 I/jmrFigure 9.4-3 Vendor Portable Cement Solidification System SECTION 9
SECTION 99.1
9.29.2.19.2.2
9.2.3 SECTION
99.39.3.1
9.3.2
9.3.3 Revision
25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 1 of 6SECTION 9PLANT RADIOACTIVE WASTE CONTROL SYSTEMS I/mab9.4Solid Radwaste System9.4.1Design BasisThe solid radwaste system is designed to process, package, store, monitor, and provide shielded storage facilities for solid wastes to allow for radioactive decayand/or temporary storage prior to shipment from the plant for off-site disposal.The solid radioactive wastes are shipped off-site in vehicles equipped with adequate shielding to comply with Department of Transportation (DOT)
regulations.
The design bases of the solid radwaste system are to:a.Minimize radiation exposure to plant operating personnel.
b.Prevent spillage and contamination spread of radioactive materials.
c.Provide safe and reliable means for handling the solid wastes.9.4.2Description9.4.2.1Sources The following are radioactive solids wastes generated in the operation of the plant:a.Process Wastes - filter sludge and spent resins from the liquid processing systems.b.Reactor System Wastes - spent control rod blades, temporary control curtains, fuel channels, and in-core ion chambers.c.Maintenance Wastes - contaminated clothing, tools, rags and small pieces of equipment which cannot be economically decontaminated.d.Operating Wastes - laundry cartridge filters, paper, rags, off-gas filters, and ventilation filters.e.Miscellaneous Wastes - solidified chemical and liquid wastes.
Major flow paths and equipment for the radwaste solids handling system and waste solidification system are shown in Drawings NH-36047 and NH-36047-2,Section 15, respectively.9.4.2.2Processing and Handling Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 2 of 6 I/mab9.4.2.2.1Chemical, Liquid and Process WastesChemical and Liquid Wastes Chemical and liquid wastes which require solidification are added to containersand solidified using special procedures as necessary. The radiation level of
these wastes is low enough to allow this operation to be done by contact
handling in a well-ventilated area. After solidification, the wastes are sealed
and placed in temporary storage for shipment along with the maintenance and operating wastes. Chemical and liquid wastes may also be used to maintain required moisture levels during the solidification of process wastes.Process Wastes
The process wastes are the largest volume of solid wastes processed in the solid radwaste system. The process wastes consist of the filter sludge from the reactor clean-up, fuel pool, and condensate filter/demineralizer systems and the radwaste filters and the spent resins from the radwaste mixed-bed demineralizer. The filter sludge and spent resins are backwashed into their
respective receiving tank, dewatered and processed in the waste solidification
system. An initial dewatering step is accomplished on the condensate and clean-up sludge by sedimentation and decantation. This serves the two-fold purpose of providing decay storage of the sludge in the tanks and reduces the
processing load on the centrifuges.Two centrifuges and two drum-filling systems ("A" system and "B" system) are provided to allow for segregation of the high level and low level sludge in the drumming step. The "B" system includes the waste solidification system (seeSection 9.4.2.2.2), and may also be used for processing sludge for solidification by an outside contractor. The "A" system is a standby system which may be
used for de-watered sludge processing. The sludge are dewatered in the
centrifuge and the moist solids fall directly into surge hoppers located beneath the centrifuges. The hoppers provide surge since only one 55 gal drum may be filled at a time. Empty drums are loaded onto a remotely operated conveyor
system which carries one drum at a time to a selected filling station beneath a hopper. The drum is filled under visual observation and then transferred to a
pre-selected storage conveyor as dictated by the radiation level of the drum contents. All operations in the handling of the process wastes, from the backwashing to the final load-out of the drums, are accomplished by remote
means.
Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 3 of 6 I/mab9.4.2.2.2Waste Solidification System The waste solidification system is part of the "B" hopper system and renders radioactive wastes into a homogeneous, solid product suitable for
transportation and subsequent disposal. The system mixes moist radioactive wastes with dry portland cement and feeds the resulting mixture into standard 55-gallon drums. The system is remotely operated and fully automated to minimize radiation exposure to personnel and to minimize operator error. The
system can also be manually operated. The control panel is located at elevation 935 in the radwaste conveyor operating galley.The solidification system was manufactured by Atcor, Inc., and consists of three basic subsystems:a.waste conditioning and metering,b.dry cement storage and metering, andc.product mixing and package filling.
The waste conditioning sub-system receives processed solid wastes from the centrifuge, adjusts the moisture content to assure a proper cement mixture, and meters the conditioned waste into the mixer/feeder unit for subsequent
mixing with cement.
Dry cement is stored in a 75 cubic foot capacity bin from which it is fed to the mixer/feeder through a combination of two screw feeders. The combined
waste product and dry cement are introduced to the mixer/feeder simultaneously. A screw flight and paddle arrangement within the mixer/feeder insures a thorough mixing action. After completion of the filling operation, the full drum is conveyed to the capping station and storage areas.
A solid radwaste drum decontamination station provides remote control washing of the drums after they are filled and capped so that radiation
exposure to personnel during this operation can be eliminated. The solid
radwaste drums are placed in temporary storage prior to shipment for disposal.
Portable equipment owned and operated by independent contractors has also been used at Monticello for the solidification of process and miscellaneous wastes. This equipment and its associated concrete solidification process is
similar to that provided by Monticello in-plant equipment.
The interface connections from the plants process waste system to the independent contractors portable equipment consists of a waste hose from the
radwaste system, a vent hose from the liner back to the radwaste building ventilation system, electrical, air and demineralized water for the process wasteprocessing unit. A sketch of the system is shown in Figure 9.4-3. Alarms are provided to annunciate high sludge levels in the liner. Transfer hoses are Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 4 of 6 I/mableak-tested prior to use. The waste in the phase separators tanks is normallytransferred to the processing liner in basically the same way as the ATCORsystem. Waste is centrifuged to "B" hopper where liquid has been added,mixed and then pumped to the vendor's liner. Solidification is then conducted
in a liner contained inside a shield cask or a shipping cask.
The solidification system mixes separate feeds of radioactive wastes and dryPortland cement in the liner. Normal operation of the system includes transfer of dry cement from a cement storage bin or from a bulk cement truck into thewaste container. The waste from the plant's waste storage tank is pumped to the shipping container by the plant's permanently installed pumps. After the
correct metered amount has been transferred, the waste flow is stopped and
the correct amount of additives is added to pre-condition the waste. Dry Portland cement is transferred to the liner with a pneumatic transfer system.
Mixing of the waste with the additives and the cement is accomplished by a
disposable agitator pre-mounted in the liner which is driven by a hydraulic motor. Instrumentation is available to monitor the level of waste and cement
level in the liner and the temperature of the cement billet during solidification.Prior to transferring the waste to the liner, a Process Control Program (PCP) is used to verify solidification and to determine the quantities of additives and
cement required. In this procedure a sample of the waste is obtained and
processed to ensure that a solidified product can be obtained.
The primary method for handling solid radwaste is to bypass the B-centrifuge and B-hopper via the bypass line. This method sends solid radwaste directly from the radwaste holding tanks to the waste dewatering system, the
RDS-1000.The RDS-1000, manufactured by Chem-Nuclear Systems, Incorporated (CNSI), is a waste processing system installed for use at the Monticello plant.
This system is a waste dewatering system with connections to the plant systems via the bypass line as noted above. A water return line to the
radwaste drains is used to route extracted liquid back to the plant for
processing. A topical report for the waste dewatering system has been
reviewed by the NRC. The NRC found this system and its operating procedures to be an acceptable process for the preparation of waste for burialto meet the requirements of 10CFR61 (Reference 13). Major flow paths and equipment are shown in Drawing NH-119062, USAR Section 15.9.4.2.3Storage and Shipment for Disposal A radwaste storage building (32 x 80.5) is provided for the solid radwaste truck loading area. This sheet metal building is provided with shield walls, floor
drains, heating and fire protection systems. An overhead crane (capacity of 10
tons) is located in the building. The building is designed to enclose the
radwaste shipping truck and to facilitate loading of the truck.
In addition to normal pendant controls, the overhead crane is radio controlled to enable the crane operator to select the best location to handle the waste and
minimize his radiation exposure.
Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 5 of 6 I/mabA radwaste shipping building is erected along the west side of the radwaste storage building. The building is a metal, steel framed building 25-6 x 127.The waste is packaged, stored and shipped in accordance with applicable DOT
and NRC regulations. All activities are performed in accordance with a Process Control Program and are under the control of the plant staff.9.4.2.3.1Hardware and Other Wastes Not Requiring Solidification Reactor mechanical wastes are stored for decay in the spent fuel storage pool
and subsequently packaged in suitable approved shipping containers for shipment to an approved off-site disposal site. Maintenance and operating
wastes are collected in containers located in appropriate zones in the plant, as dictated by volume and degree of contaminated wastes. The activity level of these wastes is generally low enough to permit contact handling. After the
containers are filled at their respective collection point, the waste is transferred to the Radwaste Building where it is either prepared for shipping off-site to a
processing and/or disposal facility or compacted into drums by a hydraulic press bailing machine. If compacted, ventilation is provided to maintain control of contamination spread during the compacting and packaging operations. The
compacted waste drums are then sealed and placed in temporary storage
along with the non-compressible wastes until final shipment to the burial site.
Other equipment which is too large to be handled in this way requires special procedures. Since the need for handling of large equipment is quite infrequent, providing storage facilities in advance is not justified. Handling of such
equipment depends upon the radiation level, transportation facilities, and
available storage sites. Procedures for decontamination, shielding, shipment,monitoring and storage of such items are developed as necessary.9.4.2.4Process Control Program All activities are performed in accordance with a Process Control Program (PCP) and are under the control of the plant staff. Waste classification andwaste form requirements of 10CFR Part 61 are ensured by the PCP. The
Process Control Program was approved by the NRC in a letter dated February 8, 1983 (Reference 10). A description of changes to the PCP are submitted to the NRC with the Annual Radioactive Effluent Release Report.9.4.3Performance Analysis Radiation exposure to plant operating personnel is minimized by shielding around the sludge collection tanks, centrifuges, drum filling systems, drum storage conveyors and temporary storage areas. Methods are provided for
gross decontamination of equipment which may require periodic maintenance.01103927 Revision 25 USAR 9.4MONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 6 of 6 I/mabThe majority of the radioactivity released from the reactor process system is collected and retained on the filter sludge and spent resins. Following the dewatering step, the wastes are rendered relatively immobile and the potential for release is reduced. During solidification, radiation level detection is provided to preclude exceeding the curie limits of the transportation container. System
interlocks are provided to prevent spills and improper operation. A loss of power
de-energizes all equipment. Building ventilation is provided to reduce contamination spread with the building ventilation air being filtered through high-efficiency filters prior to discharge via the monitored Reactor Building vents.
The release of activity from the solid radwaste system to the environs is extremely low.
SECTION 99.5
Revision 22 USAR 9.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 1 of 2SECTION 9PLANT RADIOACTIVE WASTE CONTROL SYSTEMS I/jmr FIGURESFOR ADMINISTRATIVE USE ONLYResp Supv:CNSTP Assoc Ref:
SR:2yrs N Freq: USAR-MANARMS:USAR-9.FIGURESDoc Type:Admin Initials:Date:
9703 Revision 22 USAR 9.FIGURESMONTICELLO UPDATED SAFETY ANALYSIS REPORT Page 2 of 2 I/jmrFigure 9.4-3 Vendor Portable Cement Solidification System