ML081130681
ML081130681 | |
Person / Time | |
---|---|
Site: | Prairie Island |
Issue date: | 04/30/2008 |
From: | Nuclear Management Co |
To: | Office of Nuclear Reactor Regulation |
References | |
FOIA/PA-2010-0209, L-PI-08-024 | |
Download: ML081130681 (168) | |
Text
Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.0 PROPOSED ACTION NRC "-The report must contain a description of the proposed action, including the applicant's plans to modify the facility or its administrative cont rol procedures-. This report must describe in detail the modifications directly affecting the environment or affecting plant effluents that affect the environment-." 10 CFR 51.53(c)(2)
Nuclear Management Company (NMC) proposes that the U.S. Nuclear Regulatory Commission (NRC) renew the operating licenses for Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2 for the maximu m period currently allowable under the Atomic Energy Act and NRC's regulations (10 CFR 54.31). This action would provide the option to operate PINGP up to 20 years beyond the current operating license terms expiring on August 9, 2013 (Unit 1) and Oc tober 29, 2014 (Unit 2). Renewal would thereby enable the State of Mi nnesota, Xcel Energy and its subsidiary companies, and other participants in the wholesale power ma rket to rely on PINGP to meet future electric power needs through the period of extended operation of these generating units. In the following sections of Chapter 3, NMC presents a description of the PINGP site and activities relevant to assessments presented in Chapter 4 of this Environmental Report (ER). Section 3.1 provides a general description of plant design and operating features. Sections 3.2 th rough 3.4 describe potential cha nges to support the renewed PINGP Unit 1 and PINGP Unit 2 operating licenses.
PROPOSED ACTION Page 3-1 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.1 GENERAL PLANT INFORMATION General information about the design and operational features of PINGP from an environmental impact standpoint is available in several documents. Among the most comprehensive sources are the Final Envir onmental Statement (FES) prepared by the NRC's predecessor agency, t he U.S. Atomic Energy Commission (AEC) and the Updated Safety Analysis Report (USAR).
In 1973, the AEC issued an FES that analyzed impacts of constructing and operati ng a two-unit plant with a cooling tower-based heat dissipation system (AEC 1973). In compliance with NRC regulations, NMC routinely updates the USAR to reflect current plant design and operating features (NRC 1996). The major structures, housed faci lities, and nearby areas are shown in Figure 3.1-1.
Major site buildings include the following: Unit 1 and Unit 2 contai nment buildings that house the nuclear steam supply systems including the reactors, steam generators, reactor coolant pumps, and related equipment; The auxiliary building that houses ma jor components of the primary component cooling water system, boric acid storage tanks and pumps, and other safety-related equipment; The turbine building, where the turbine generators, main condensers, turbine plant heat exchangers, and relat ed equipment are housed; Other structures and facilities of inte rest within the site boundary include the PINGP substation, intake and plant screenhouses, intake and discharge canals, Independent Spent Fuel Storage Installation (ISFSI), four mechanical draft cooling towers, and emergency diesel generators. 3.1.1 REACTOR AND CONTAINMENT SYSTEMS PINGP is a two-unit plant utilizing pressurized water reactors. The plant was originally constructed with two pressurized light-water reactor nuclear steam supply systems and turbine generators designed an d manufactured by Westinghouse Electric Company (Scientech 2005). Initial fuel loading was completed in 1973 for Unit 1 and 1974 for Unit
- 2. Following a period of te sting, full commercial operat ion began December 16, 1973 for Unit 1 under Facility Operating Licens e Number DPR-42, and December 21, 1974 for Unit 2 under Facility Operating Lic ense Number DPR-60 (N MC 2007, p. 1.1-1).
The containment for each unit consists of tw o systems. The primar y containment is a cylindrical steel pressure vessel with a hemispherical dome and ellipsoidal bottom designed to withstand a lo ss-of-coolant accident. The secondary containment is a cylindrical shield building constructed of re inforced concrete which serves as radiation shielding for normal operation and for the loss-of-coolant condi tion. The shield building also acts as a secondary containment structure for control of containment leakage PROPOSED ACTION Page 3-2 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report (NMC 2007). The shield buildings are cylindrical (205 feet hi gh by 120 feet in diameter), each capped with a hemispheric dome (AEC 1973, p. III-1).
PINGP has a design rating of 1650 megawa tts-thermal (MWt) per reactor, which corresponds to a gross electrical output of 575 megawatts-electrical (MWe). Each reactor is capable of an ultimate therma l power output of 1721.
4 MWt, and all steam and power conversion equipment, including the turbine generat or, has the capability to generate a maximum calculated gross unit out put of 592 MWe. All plant safety systems, including containment and engine ered safeguards, were designed and originally evaluated for operation at the maximum power level of 1721.4 MWt (NMC 2007, p. 1.1-2). Unit 1's original Westingho use steam generators were replaced with Framatome-ANP designed generat ors in 2004 (AREVA 2006).
3.1.2 NUCLEAR
FUEL PINGP is licensed for low-enriched uranium-d ioxide fuel with enric hments to a nominal
5.0 percent
by weight uranium-235 and an average fuel burn-up for the peak rod that does not exceed 62,000 megawatt days per metric ton uranium (MWd/MTU). The uranium-dioxide fuel is in the form of high-d ensity ceramic pellets. Fuel rods used in the reactors consist of Zircaloy with fuel pel lets stacked inside and sealed with welded end plugs. The fuel rods are fabricated into a ssemblies designed for loading into the reactor core. The PINGP reactor cores contain 29 control rod assemblies and 121 fuel assemblies. Refueling of the reactors is performed every 20 mont hs with approximately 40 percent of the fuel being replaced during each refueling outage. PINGP has two spent fuel pools, a larger one to store spent fuel and a smaller one intended primarily to handle a spent fuel shipping cask. New racks were installed in 1981, and resulted in the curr ent pool storage capacity of 1,386 assemblies (MEQB 1991, Appendix D). The NRC has licensed an Independent Spent Fuel Storage Installation (ISFSI) at PINGP, allowing up to 48 casks.
Prior to 2003, State law lim ited the authorized use to 17 casks, but new State law enacted in 2003 now allows use of up to the 48 casks permitted by the NRC. Currently, there are 24 casks installed in the ISFSI (Minnesota Legislative Reference Library 2006). 3.1.3 COOLING AND AUXILIARY WATER SYSTEMS 3.1.3.1 Water Use Overview Water for condenser cooling is withdrawn from the Mississippi River. Water used for service water cooling, screen wash, irrigation, and domestic water supply is groundwater withdrawn from on-site wells.
Station surface water and groundwater withdrawals are governed by water appropr iation limits set by the Minnesota Department of Natural Resources (MN DNR). Under Water Appropriations Permit Number 690171, PINGP may withdraw a maxi mum of 1,200 gallons per minute (gpm) of groundwater from two on-site wells for the domestic water system. A third well PROPOSED ACTION Page 3-3 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report provides domestic and irrigation water for the Training Center.
Water Appropriations Permit Number 690172 limits withdrawal of surf ace water from the Mississippi River for condenser cooling to 630,000 gpm.
The FES related to the Prairie Island Nucl ear Generating Plant (AEC 1973) describes the original configuration of the plant's cooling water systems, which were extensively modified in the early 1980s. As designed an d initially operated, the plant withdrew cooling water from the Mississippi River (Sturgeon Lake) via a 750-foot-long intake canal that extended from the river shore line to the screen house, where a trash rack removed large debris and four (3/8-inch mesh) traveling screens (per unit) removed fish and smaller debris. A skimmer wall (barrier) at the mouth of the intake canal prevented large floating objects from entering the intake canal. The plant's heated discharge flowed into a discharge basin, from whic h it was (depending on plant operating mode) either pumped to the cooling towers or discharged to the river via an 800-foot-long
canal. The plant could be operated in any one of three modes: open cycle (once-through flow, with no cooling towers in operation), helper cycle (once-through flow with cooling towers in operation), and closed-cycle (recirculation of up to 95 percent of the cooling water flow). The plant's cooling system was heavily modi fied in the early 1980s to reduce impacts of plant operation on aquatic communities (S tone & Webster 1983). A new intake screenhouse with improved traveling screens was constructed across the mouth of intake canal. A fish return line was in stalled to convey organisms washed from the traveling screens back to the Mississippi River. A new, half-mile-long discharge canal
with a north-south orientation was created by building a 2,350-foot-long dike that paralleled the river shoreline. A new di scharge structure was built at the southern terminus of the canal, and connected to the river's edge by four underground discharge pipes. The new submerged jet discharge was intended to promote rapid mixing of the heated effluent, keep fish out of the discharge canal, and prevent recycling of warm discharge water (Stone & Webster 1983). The intake and discharge modifications were
completed in 1983. 3.1.3.2 Circulating Water System As previously discussed, PINGP withdraws water from the Missi ssippi River for its circulating water (condenser cooling) system.
Key components of the circulating water system and closely related cooling tower system are the intake screenhouse, plant screenhouse, circulating water pumps, condens ers, discharge stru cture, mechanical draft cooling towers, discharge canal, and disc harge structure, show n in Figure 3.1-1.
The PINGP cooling water intake system is designed to minimize impacts to fish populations. Aquatic organisms on the traveling screens and in the attached buckets are lifted to the level of the fish sprays and washed off into a fish collection trough within four minutes. Removal of the fish and or ganisms is accomplished on the upward travel side with a low pressure [10 pounds per square inch (psi)] inside spray when fine mesh screen is used and with a low pressure (20 psi) outside spray when coarse mesh screen is used. Debris is removed by a backsi de interior high pressure (50 psi for fine PROPOSED ACTION Page 3-4 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report mesh and 100 psi for coarse mesh) spray system. In spring and summer (April 1 - August 31), traveling screens are equipped with fine mesh (0.5 millimeter) panels (Xcel Energy 2006a). For the remai nder of the year, conventiona l screens with coarse mesh (3/8 inch) panels are employed. Trave ling screens can be operated over a range of speeds, depending on panel mesh size and debris loading. The pump supplying the 50 psi fine mesh spray is run at a higher speed to provide a 125 psi spray to supplement the 100 psi coarse mesh spray during periods of high trash loading. The separate fish and debris troughs combine to form a common trough. The fi sh and debris are then returned to the river through a buried pipe. The pipe discharges at a point approximately 1,500 feet south of the intake screenhouse. Transferring the fish downriver, outside of the influence of the coo ling water intake, serves to prevent re-impingement of weakened or disoriented fish.
The pipe is designed for velocities between 3 and 5 feet per second with higher velocities encountered for short durations.
All internal surfaces of the pipe are sm ooth to preclude abrasion damage. The pipe discharges below the mean water elevation at a depth which ensures submergence below any ice cover.
River water flows into the intake screenhous e through eight (18.5 foot by 11.2 foot) intake bays, each equipped with a trash ra ck, a 10-foot-wide traveling screen, and high/low pressure wash systems (Xcel Energy 2006a). Bypass gates permit a continuous flow in the event that traveling screens become clogged with debris (Stone &
Webster 1983). After moving through the tr aveling screens, circulating water flows down the intake canal to the plant screenhouse, where the circulating water pumps are housed. Four circulating water pumps (two per nuclear unit) supply water to the condensers for cooling. Each pump has a design capacity of 147,000 gpm, meaning the circulating water flow is approximatel y 294,000 gpm per unit (NMC 2007, pg. 11.5-1) and the total circulating water flow is appr oximately 588,000 gpm.
Smaller volumes of water are also withdrawn for its cooling water (i.e., service water) system, which supplies cooling water to a variety of feedwater pumps, air compressors, and small heat exchangers in the plant. 3.1.3.3 Circulating Water System Operating Modes After passing through the condensers, cooling water is piped to a discharge basin from which it may be (a) pumped to the cooling to wers (closed-cycle or helper cycle) or (b) allowed to flow to the discharge canal (open c ycle) via the distribution basin. If it is pumped to the cooling towers, the cooling to wer outfall may be routed back to the intake canal (closed cycle) or flow to the discharge canal (helper cycle). The distribution basin receives circulating water flow from t he discharge basin duri ng open-cycle operation and from the cooling tower return canal dur ing closed-cycle operation.
During transition periods (from closed cycle to open cycle), the dist ribution basin receives flow from both sources. The cooling tower system is comprised of fo ur towers, fans, water distribution headers and basins. Each tower has one cooling tower pump and is made up of 12 cells
grouped together (a bank).
PROPOSED ACTION Page 3-5 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report The cooling tower pumps intake water from the discharge basin and discharge into individual distribution pipes to the top of the cool ing towers. The pumps are vertical, dry pit pumps mounted so that the casing will be flooded with the water in the discharge basin at normal level. The pump motors are mounted on, and suppor ted by, the pump.
The intakes to the pumps are submerged to prevent the intake of air from any cause. Spray nozzles at the top of the cooling towers break-up the wate r stream into small streams which drop by gravity through a maze of "fill" to a basin at the base of the towers. Fans draw air up through the stream s of water and the heat of the water is carried into the atmosphere by the airstream. Fr om the cold water basin at the bottom of the towers, the water flows through the coo ling tower return canal to the distribution basin (NMC 2007). The towers are designed to accommodate the full circulating water flow of the plant and are capable of remo ving up to 96 percent of the waste heat generated by plant operation (AEC 1973).
Operation of PINGP's circulating water system is governed by spring and fall "trigger points." The spring trigger point is defined as the point in time that the daily average ambient river temperature increases to 43 degrees Fahrenheit (F) or above for five consecutive days, or April 1, wh ichever occurs first. The fall trigger point is the point at which the daily average upstream ambient ri ver temperature falls below 43 degrees F for five consecutive days. From the spri ng trigger point through the fall trigger point, PINGP is required to operate the cooling to wers as necessary to meet the following requirements: (1) the temper ature of the receiving wate r immediately below Lock and Dam No. 3 can not be raised by more than 5 degrees F above ambient, (2) the cooling water discharge can not exceed a daily aver age temperature of 86 degrees F, and (3) if the daily average ambient rive r temperature reaches 78 degr ees F for two consecutive days, all cooling towers shall be operated to the maximum extent practicable (NPDES
Permit No. MN0004006).
From the fall trigger point through March 31, the temperat ure of the receiving water immediately below Lock and Dam No. 3 can not be raised above 43 degrees F for an extended period of time. If the receiving water temperat ure exceeds this 43-degree F limit for two consecutive days, NMC must notify the Commissioner and the MN DNR.
The Commission may require NMC to operate t he cooling towers or take alternative action to meet the 43-degree F crit erion (NPDES Permit No. MN0004006). PINGP is equipped with a deicing system to prevent the formation of ice on trash racks, traveling screens, and bypass gates (Stone and Webster 1983). Warm water is
pumped from the discharge canal to the intake screenhouse via a 30-inch-diameter pipe buried below the frostline. The warm water is discharged at the bottom of the approach canal, directly in front of the intake screenhouse. 3.1.3.4 Biofouling and Scale Control PINGP uses a cleaning system to mechanically remove biofouling micro-organisms from circulating wat e r piping. The PI NGP NPDES permit provides for periodic chlorine/bromine use in the circulating water system to treat for pathogenic amoeba (see Section 4.12) and zebra mussels (NPDES Permit No. MN0004006). The cooling PROPOSED ACTION Page 3-6 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report water system (service water system), however, is treated with oxidizing biocides (chlorine and bromine) to prevent the growth of biofouling mi cro-organisms. The current PINGP NPDES permit limits the release of total residual bromine and total residual chlorine at Outfall SD 001 (combined circulat ing water and cooling water discharge) to 0.001 and 0.04 milligrams per liter (mg/L), respectively, during continuous application and 0.05 and 0.2 mg/L, respectively, during in termittent application (NPDES Permit No.
MN0004006). 3.1.3.5 Domestic Water Supply and Sanitary Wastewater Treatment NMC operates three groundwater wells to me et the domestic water needs of PINGP.
Two main wells, each equipped with 300-gp m pumps, supply the majority of the domestic water and are permitted to withdraw a total of 50 million gallons per year. The actual usage for these wells averaged approx imately 60 gpm for the years 2000 through 2005. A third well provides domestic and irrigat ion water for the Trai ning Center. This well is equipped with an 80-gpm pump and is permitted to withdraw 4.7 million gallons per year (NSP 2006). Actual use for the years 2000 through 2005 averaged 4 gpm (TtNUS 2006). The plant's sanitary wastes are directed to seven septic systems, which are pumped on varying schedules. The systems are designated as the Plant Septic (consisting of three tanks), the Warehouse 1 Holding Tank, the Guardhouse Septic, the Office Complex, the Fabrication Shop, the New Administration Building, the Environmental Lab, and the Prairie Island Training Cent er (Xcel Energy Undated). 3.1.4 RADIOACTIVE WASTE TREATMENT SYSTEMS 3.1.4.1 Liquid Radioactive Waste Systems Radioactive liquids entering the Waste Dispos al System are collected in intermediate holding tanks for determination of subsequent tr eatment. If liquids are to be released, they are first sampled and analyzed to determine the quantity of radioactivity and if it meet acceptable release criteria. The liquid wastes are then processed as required for reuse or released under controlled conditions and in accordance with applicable limits of 10 CFR 20 and the design objectives of Appendix I to 10 CFR 50 (NMC 2007).
The bulk of the radioactive liquid drained from the Reactor Coolant System is processed by the Chemical and Volume Control System recycle train, and retained inside the plant.
This minimizes liquid input to the Waste Dis posal System which processes relatively small quantities of generally low activity le vel wastes. The processed water from the waste disposal system, from which the majority of the radioactive material has been removed, may be reused or released through a monitored line to the discharge canal downstream of the coo ling towers (NMC 2007).
PROPOSED ACTION Page 3-7 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.1.4.2 Gaseous Radio active Waste Systems The gaseous radwaste system is designed to process and control the release of gaseous radioactive effluents to the site environs so that the offsite radiation dose rate does not exceed the limits specified in 10CFR20 and the design objectives of Appendix 1 to 10CFR50 are met. Waste gases are processed by one of two interconnected equipment trains. The low leve l loop provides sufficient st orage capacity for cover gases from the nitrogen blanketing system to minimize the need to vent gases which accumulate as a result of shutdown operat ions. Discharges of fission gases from the system are limited to maintenance vents, unavoidable equipment leaks, and infrequent gas decay tank releases to dispose of gas es accumulated by inflows from shutdown operations and miscellaneous vents.
Controls are provided to regulate the rate of release from these tanks through the monitored plant vent. The high level loop was designed to accumulate, concentrate, and contain fission gases at high activity concentrations from continuous purging of the volume control tanks gas space. It would
provide continuous removal of fission gases from the letdown cool ant to maintain the coolant fission gas concentrations at a low re sidual level. This loop can perform these functions and/or be used for reserve holdup capacity of low level loop gas (NMC 2007, Section 9.3). 3.1.4.3 Solid Radioactive Waste Systems The solid radiological waste system is designed to package, store, and provide shielded storage facilities for solid wastes and to allo w temporary storage prio r to shipment from the plant for off-site processing or disposal. The system is designed to meet the requirements of 10 CFR 20, 10 CFR 71, and 49 CFR 170-189.
Solid wastes consist mainly of dry active waste (DAW) such as contaminated paper, plastic, wood, metals, and spent resin. DA W may be compacted for disposal or storage or may be sent off-site for fu rther processing, such as sort ing or incineration. The by-product of such off-site processing (inciner ator ash for example) may be returned to the plant site for storage if no di sposal site is available. Contaminated metals may be compacted on-site for storage or disposal. Contaminated
metals may also be sent off-site for pr ocessing such as decontamination or metal melting. Spent resin originates in any of several syst em ion exchangers. Spent resin is flushed to a resin shipping liner for disposal or off-si te processing. Alternatively, resin may be placed in on-site storage if a disposal site is not available. NMC plans to continue managing its low-level radioactive waste in compliance with all applicable regulations established by state and federal agencies.
Solid wastes received at disposal sites mu st meet the requirem ents of 10 CFR 61 relating to waste form and classification as well as disposal site-specific regulations (NMC 2007, Section 9.4).
PROPOSED ACTION Page 3-8 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.1.5 NON-RADIOACTIVE WASTE MANAGEMENT As outlined in Xcel Energy Environmental Po licy, PINGP is committed to conducting its business in an environmentally responsible manner (Xcel Energy 2006b). One element of this policy is ensuring that wastes gener ated by business activities/operations are managed in compliance with applicable regulati ons and in a manner pr otective of the environment and human health. It also incl udes, where appropriate, minimizing the creation of waste, especially hazardous waste.
Xcel Energy's Waste Management Guidanc e Manual (Xcel Energy 2006c) assists PINGP employees in the identification of regulated wastes.
It includes directions for selecting waste collection containers, storage and labeling requirements, and transport and disposal procedures. Training, em ergency planning, and record keeping requirements associated with waste management are also de scribed. Additional topics on waste regulations, employee responsibilities, and handling a regulatory inspection are included.
Proper management of regulated waste fa lls under three federal agencies: the Environmental Protection Agency (EPA), the Occupational Safety and Health
Administration (OSHA), and the Department of Transportati on (DOT). Congress began the process of waste regulation with the passage of the Resource Conservation and Recovery Act of 1976 (RCRA). This ac t authorized the EPA to write regulations providing for a comprehensive management system for hazardous wastes. It also imposed 'cradle to grave' responsibility on the generator of a hazardous waste, meaning Xcel Energy never loses liability for its waste. As a result, Xcel Energy does not select waste disposal vendors on cost alone, but also evaluates and selects transportation and disposal companies that demonstrate co mpetence in managing hazardous wastes.
RCRA authorizes states to develop their own waste regulations. The State of Minnesota has authorization to manage their hazardous waste management programs and have developed additional regulations making them more restrictive than federal requirements (MN Rules Chapter 7045).
OSHA is involved in waste management through the Hazard Communication (HAZCOM) Standard, requiring th at employers inform and train workers in proper handling of hazardous substances. Under the Hazardous Waste Operations and Emergency Response (HAZWOPER) Standar d, OSHA established training requirements for workers that respond to releases of hazardous substances.
The DOT considers hazardous wastes a subs et of hazardous materials, which means many regulated wastes are subject to DOT requirements during shipment. DOT regulations contain packaging specifications, container marking and labeling requirements, emergency reporti ng requirements, release re sponse requirements, and a complex tracking system using shipping papers and manifests. DOT also requires training for employees with re sponsibility for the shipment of hazardous materials.
Non-radioactive waste is produced from plant maintenance, cleaning, and operational processes. The majority of the waste generated consists of non-hazardous waste oil, PROPOSED ACTION Page 3-9 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report oil-filled equipment used in operations and maintenance, and oily debris. Universal waste defined by Minnesota Pollution Control Agency (MPCA) includes lighting ballasts, polychlorinated biphenyl (PCB) small capacit ors, mercury containing devices and batteries, antifreeze, circuit boards, elec tronics, photographic negatives, cathode ray tubes (CRTs), alkaline batteries, and non-TC LP fluorescent and HID lamps, common to any industrial facility, comprise a majority of the remaining waste volumes generated.
Hazardous waste routinely makes up a sma ll percentage of the total waste generated and consists of spent and off-specification (e.g. shelf-life expired) chemicals, laboratory chemical wastes, Freon-contaminated oil, and occasional project-specific wastes. As outlined in the company environmental policy, Xcel Energy is committed to considering pollution prevention in busine ss planning and decisio n-making processes. Pollution prevention reduces wastes, which in turn reduces regulatory burdens, reduces liability, and saves money. It also helps conserve valuable resources and protects human health and the environment. Pollution prevention is achieved by utilizing the Waste Management Hierarchy fo r reducing waste generation.
This hierarchy prioritizes waste reduction though source reduction, r euse/recycle, and treatment and disposal, respectively (Xcel Energy 2006c). 3.1.6 TRANSMISSION FACILITIES 3.1.6.1 History/Background When PINGP was built, its generating and transmission facilities were owned and operated by Northern States Power, a regulated utility with headquarters in Minneapolis, Minnesota. In May 2000, Northern States Power transferred its authorization to operate PINGP to NMC, a contract/oper ations firm that currently ov ersees the operation of two nuclear plants in Minnesota. Northern Stat es Power continued to operate and maintain the PINGP transmission lines when the responsibility for managing the PINGP generating facilities was transferr ed to NMC. Therefore t he discussion that follows on the planning, construction, and modification of PINGP transmission facilities in the 1970s and 1980s applies to Northern States Power, whereas the discussion of current maintenance and vegetation management practices applies to Xcel Energy.
Before PINGP was built, a 345-kilovolt (k V) line was installed between the Red Rock substation in St. Paul and the Adams substa tion in Mower County, 74 miles south of Prairie Island (NSP 1971, p. II-25). This line was designed to pass near the proposed PINGP site and link to the new plant once bui lt, thereby providing connections between the plant and St. Paul (Red Rock) and between the plant and southeastern Minnesota (Adams). When PINGP was built, the Red Rock - Adams line was divided, and the two new "halves" connected to PINGP by means of a 2.5-mile-long corridor that runs to the plant substation.
The FES noted that two new 345-kV lines were required to connect the plant to the regional electric transmission syst em (AEC 1973, p. III-1).
One new line was built from PINGP Unit 1 to the Blue Lake substation in Scott County; another was built from PINGP Unit 2 to the Red Rock substation in south St. Paul. The new line from Unit 1 to PROPOSED ACTION Page 3-10 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report the Blue Lake substation required constructi on of a new corridor to the Inver Grove substation, in Dakota County; the rema ining segment, between Inver Grove and the Blue Lake substation, was routed along an exis ting corridor. The entire length of the new line from Unit 2 to the Red Rock substation was routed along an existing corridor.
In total, Northern States Power built 78 m iles of new line to deliver power to the transmission system (AEC 1973). Because NSP was able to take advantage of existing transmission corridors, it was only necessary to acquire 33 miles of new right-of-way. NRC defines the transmission corridors of concern for license renewal as those constructed for the specific purpose of connecting the plant to the transmission system [10 CFR 51.53(c)(3)(ii)(H)]. NRC further elaborates in the GEIS and guidance that the corridors of concern are those that were "constructed between the plant switchyard to its connection with the existing transmission system." Supplement 1 to Reg. Guide 4.2 (NRC 2000) recommends that applicants "specifically identify those transmission lines that were identified in the construction permit review as being constructed to connect the plant to the transmission system." AEC's 1968 construction permit review for PINGP predated the 1970 enactment of the National Envir onmental Policy Act. The FES related to the Prairie Island Nuclea r Generating Plant (AEC 1973) was concerned with impacts of "-the continuation of construction permits-and the issuance of operating licenses-for the startup and operation of the PINGP" and considered impacts of both construction and operatio n of the plant. Two 345-k V transmission lines, PINGP - Blue Lake and PINGP - Red Rock 2, were considered in the 1973 FES and will therefore be considered for transmission-rela ted impacts in Chapter
- 4. The two 2.5-mile-long transmission line connections built to connect PINGP to the Red Rock 1 and Adams lines will also be analyzed. In addition, the 161-kV line owned by Great River Energy that runs from PINGP to Spring Creek is included in the scope of this analysis. 3.1.6.2 Current Syst em Configuration The output of PINGP is deliver ed to the substation just north of the generating facilities with 345-kV and 161-kV switchyards (NMC 2007, Section 8.2). Five transmission lines leave the switchyards via three transmission corridors: One corridor, running west, contains the 2.5-mile-long transmission line connection to Red Rock 1 and Blue Lake 345-kV lines. A second corridor, running west, contains the Red Rock 2 and the 2.5-mile-long transmission line connection to Adams 345-kV lines. A third corridor, running south, cont ains the Spring Creek 161-kV line.
These five transmission lines connect PING P to the regional tr ansmission system (NMC 2007, Section 8.2.1). The current transmission system is summarized in Table 3.1-1.
Figure 3.1-1 shows the layout of the transmission lines leav ing the PINGP substation.
Figure 3.1-2 presents the routes of the five in-scope transmission lines.
PROPOSED ACTION Page 3-11 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report Northern States Power and Great River Energy designed and constructed the PINGP transmission lines in accordance with industr y guidance that was current when the lines were built. Ongoing surveillance and maintenance of PINGP-related transmission facilities ensure continued conformance to design standards. Section 4.10 examines the conformance of the lines with the National Electrical Safety Code requirements on line clearance to limit shock from induced currents (IEEE 1997).
Xcel Energy uses a variety of methods to ensure that transmissi on corridors are kept free of brush and fast-growing trees that could interfere with transmission facilities (e.g., towers, conductors, sub-stations). Bec ause transmission corridors cross areas with different kinds of terrain and vegetation, Xc el Energy employs an Integrated Vegetation Management (IVM) approach that includes bo th mechanical and chemical control methods. IVM involves the judicious use of a range of vegetation management treatments including tree removal, pruning, mowing, an d chemical (herbicide) application (Xcel Energy 2005).
Great River Energy also uses an IVM program to enhance wildlife along power line rights-of-way. This effort includes the use of low-
volume biodegradable herbicides to remove unwanted woody species, while leaving behind the grasses, wildflowers, and low-growing trees preferred by butterflies, songbirds, wild turkey, and deer (Great River Energy 2006). The goal of Xcel Energy's IVM program is to develop site-specific, environmentally-sensitive, and cost-effective solutions to vegetation management near transmission and distribution facilities. The pr imary objective is to keep transmission facilities clear of tall-growing trees and brush that could grow too close to conductors and interfere with electricity transmission. This is accomplished with routine ve getation management on each transmission circuit that is conduct ed on an established maintenance cycle. Xcel Energy has adopted the "Wire zone/Border zone" concept to allow for different types and heights of vegetation in transmissi on corridors (Xcel Energy 2005). The goal is to manage vegetation in rights-of-way so as to establish a "wire zone" directly underneath towers and conductors with low-growing forbs and grasses and a "border
zone" (from outside edge of wire zone to edge of right-of-way) with slow-growing shrubs and trees that do not grow high enough to interf ere with transmission structures. Areas outside the border zone are peri odically inspected for tall "
danger trees" (dead, dying, or diseased trees that could fall and interfere with transmission lines).
These trees are removed expeditiously, outside of the normal maintenance cycle. Xcel Energy has adopted guidelines that govern the use of her bicides in its transmission corridors (Xcel Energy 2005). Contract ors engaged in vegetat ion management must submit plans/proposals to Xcel Energy
's Vegetation Management representative detailing any planned use of herbicides. Pr oduct labels and Material Safety Data Sheets must be supplied to the Vegetati on Management representat ive along with the treatment plan. In addition to this oversight of site-specific vegetation management plans, Xcel Energy's Vegetation Management Guidelines (provided to all contractors engaged in vegetation management) prohibit the use of herbi cides outside of right-of-way boundaries and instruct contractors to discontinue the use of herbicides PROPOSED ACTION Page 3-12 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report immediately if a property owner objects to their use, pending the resolution of any issues. Xcel Energy plans to maintain these transmission lines, which are integral to the larger transmission system, indefinitely. These transmission lines will remain a permanent part of the transmission system even after PINGP is decommissioned. 3.1.6.3 Avian Mortality R esulting from Collisions with Transmission Lines NRC (1996) noted in the GEIS that "No relative ly high collision mortality is known to occur along transmission lines associated wi th nuclear power plants in the United States other than the Prairie Island plant in Minnesota."
The statement refers to a 5-year study in which bird carcasses were collected along two transmission corridors originating at PINGP (Goddar d 1977; 1978; 1979). The corri dors were searched from the substation just north of the PINGP generating facilities to the transmission towers nearest the Vermillion River (Goddard 1977), a dist ance of about 1.5 miles. A total of 453 bird carcasses representing 53 species were found during the 5-year period. About 64 percent of the carcasses were found alon g the 2,500-foot east-we st portion of the corridors slightly northwest of the PINGP substation (Figure 3.
1-1). This section of the corridors is perpendicular to the bird migr ation corridor along the Mississippi River. Other avian collision studies have also found that transmission lines at right angles to avian flight paths are associated with greater collisions (Goddard 1979). As a result of the criminal prosecution of the Moon Lake El ectric Association, Inc., a Utah-based electric power company, for electroc ution of protected birds, the U.S. Fish and Wildlife Service (FWS) and several po wer companies began to discuss a method for addressing the avian electrocution pr oblem (USDOJ 2002). A Memorandum of Understanding (MOU) between the FWS and Xcel Energy, the first of its type completed in the U.S., has been in effect sinc e 2002 (NSPCM & FWS 2002). The MOU was created to establish procedures and policies dealing with mi gratory birds that may be present on NSP property, and outlined the development of an Avian Protection Plan.
Xcel Energy submits semi-annual reports to the FWS summarizing activities covered under the MOU. The Avian Protection Plan for PINGP and associated transmission lines is in development.
Very few bird carcasses have been observed at PINGP or along PINGP-associated transmission lines since 1978, but systematic sear ches or formal avian collision studies have not been conducted. Therefore, the curr ent extent of collision-related mortality and a comparison of avian mortality at PI NGP to other nuclear plants have not been evaluated. However, the GEIS noted that the mortality at PING P may not be unique, and may simply reflect the fact that surve ys were performed. NRC (1996) further states that "the issue is whether collision mortality is large enough to cause long-term reductions in bird populations." Based on a literature search, NRC (1996) concluded that avian collisions with transmission lines did not significantly reduce species populations, and bird collisions with transmission lines associated with license renewal would not cause long-term reduction in bird p opulations, and thus, collision mortality is of small significance.
PROPOSED ACTION Page 3-13 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.1.7 MAINTENANCE, OPERATION, AND INSPECTION NMC implements programs to maintain, inspect, test, and monitor the performance of plant equipment. These programs are desig ned to meet several requirements:
- 10 CFR 50, Appendix B (Quality Assuranc e), Appendix R (Fire Protection), and Appendices G and H, Reactor Vessel Materials;
- 10 CFR 50.55a, American Society of Mechan ical Engineers, Boiler and Pressure Vessel Code,Section XI, In-service Inspection and Testing Requirements;
- 10 CFR 50.65, the maintenance rule, and
- Maintain water chemistry in accordance with Electric Power Research Institute (EPRI) guidelines.
Additional programs include those implemented to meet Technical Specification surveillance requirements, those implemented in response to NRC generic communications, and various periodic maintenance, testing, and inspection procedures necessary to manage the effects of aging on structures and comp onents. Certain program activities are performed during the operation of the uni ts, while others are performed during scheduled ref ueling outages. Current maintenance, operation, and inspection activities will continue and be expanded to include programs for managing the effects of aging.
PROPOSED ACTION Page 3-14 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.2 REFURBISHMENT ACTIVITIES NRC "- The report must contain a description of - the applicant's plans to modify the facility or its administrative control procedures-. This report must describe in detail the modifications directly affecting the environment or affecting plant effluents that affect the environment-." 10 CFR 51.53(c)(2) "The environmental report must contain analyses of -refurbishment activities, if any, associated with license renewal-" 10 CFR 51.53(c)(3)(ii) "- The incremental aging management activities carried out to allow operation of a nuclear power plant beyond the original 40 year license term will be from one of two broad categories: ... and (2) major refurbishment or replacement actions, which usually occur fairly infrequently and possibly only once in the life of the plant for any given item-." NRC 1996 NMC has addressed refurbishment activities in this environmental report in accordance with NRC regulations and complementary in formation in the NRC GEIS for license renewal (NRC 1996). NRC requirements for the renewal of operating licenses for nuclear power plants include the preparation of an integrated plant assessment (IPA)
(10 CFR 54.21). The IPA must identify and list systems, structures, and components subject to an aging management review. Items that are subject to aging and might require refurbishment include, for example, piping, supp orts, and pump casings (see 10 CFR 54.21 for details), as well as those that are not subject to periodic replacement. In turn, NRC regulations for implementing the National Environmental Policy Act require environmental reports to describe in detail and assess the environmental impacts of refurbishment activities such as planned modifications to systems, structures, and components or plant effluents [10 CFR 51.53 (c)(2)]. Resource categories to be evaluated for impacts of refurbishment in clude terrestrial resources, threatened and endangered species, air quality, housing, public utilities and water supply, education, land use, transportation, and historic and archaeological resources. The GEIS (NRC 1996) provides helpful information on the scope and preparation of refurbishment activities to be evaluated in th is environmental report. It describes major refurbishment activities that utilities might perform for license renewal that would necessitate changing administrative control procedures and modifying the facility. The GEIS analysis assumes that an applicant wo uld begin any major refurbishment work shortly after NRC grants a renewed license and would complete the activities during five outages, including one major outage at the end of the 40th year of operation. The GEIS refers to this as the refurbishment period. GEIS Table B.2 (NRC 1996) lists license renew al refurbishment activities that NRC anticipated utilities might undertake. In identifying these activi ties, the GEIS intended to encompass actions that typically take place only once, if at all, in the life of a nuclear plant. The GEIS analysis assumed that a utility would undertake these activities solely for the purpose of extending plant operations beyond 40 years, and would undertake PROPOSED ACTION Page 3-15 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report them during the refurbishment period. The GEIS indicates that many plants will have undertaken various refurbishment activities to support the current license period, but that some plants might undertake such tasks only to support extended plant operations.
Examples of refurbishment activities incl ude pressurized water re actor steam generator replacement and boiling water reactor reci rculation piping replacement when these activities are carried out to ensure safe operat ions for 20 additional years. The GEIS assumes that refurbishment activities woul d take place within the 10 years prior to current license expiration and would culminate in a major outage immediately prior to the extended (license renewal) term. Because the situation at PINGP is consistent with this example, NMC is analyzing Unit 2 steam generator replacement in this environmental report as a refurbishment acti vity, pursuant to 10 CFR 51.53(c)(3)(ii).
The new steam generators would be manufactured at AREVA's Chalon Saint-Marcel plant. Delivery of the st eam generators would take place in May 2013 with installation following in September 2013 (AREVA 2006).
The refurbishment outage is expected to last approximately 80 days. Like the 2004 Unit 1 steam generator replacement, the steam generators would arrive by barge afte r journeying from France and traveling up the Mississippi River. A temporary construction area is planned to be located approximately 100 yards northwest of the turbi ne building. Several temporary buildings would be built, including a facility for prepar ing the steam generators, office space for construction contractors, and a decontamination building.
Warehouse(s) would also be built on site and would rema in after the steam generator replacement outage. Any construction would occur within the existi ng plant boundaries.
There would be no clearing of previously-undisturbed areas. No road improvements would be required because the steam generators would arrive via barge and be offloaded to a self-
propelled nuclear transporter capable of traveling on existing site roads without damage. NMC estimates that 750 worker s would be required to perform the steam generator replacement and standard outage maintenance and refueling.
PROPOSED ACTION Page 3-16 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.3 PROGRAMS AND ACTIVITIES FOR MANAGING THE EFFECTS OF AGING NRC "-The report must contain a description of - the applicant's plans to modify the facility or its administrative control procedures-. This report must describe in detail the modifications directly affecting the environment or affecting plant effluents that affect the environment-." 10 CFR 51.53(c)(2) "-The incremental aging management activities carried out to allow operation of a nuclear power plant beyond the original 40 year license term will be from one of two broad categories: (1) SMITTR actions, most of which are repeated at regular intervals -." NRC 1996 (SMITTR is defined in NRC 1996 as surveillance, monitoring, inspections, testing, trending, and recordkeeping.)
The IPA required by 10 CFR 54.21 ident ifies the programs and inspections for managing aging effects at PINGP. These progr ams are described in the Prairie Island Nuclear Generating Plant License Renewal Application, Appendix B, Aging Management Programs. Other than implementation of programs and inspections identified in the IPA, NMC has no plans to modify administrative controls that are associated with license renewal.
PROPOSED ACTION Page 3-17 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report
3.4 EMPLOYMENT
3.4.1 CURRENT
WORKFORCE NMC employs approximately 685 permanent and long-term contract employees at PINGP, a two-unit facility.
Approximately 83 percent of the employees live in Goodhue and Dakota Counties, Minnesot a, and Pierce County, Wisconsin. Table 3.4-1 presents the number of employees that reside in each of these counties. The remaining employees are distributed across 21 counties in Minnesota and Wisconsin, with numbers ranging from 1 to 47 employees per county. A few employees live outside of these two states.
PINGP is on a 20-month refueling cycle.
During refueling outages, site employment increases above the permanent work force by as many as 925 workers for temporary duty (based on 2003 to 2006 normal refueling outage workforces at PINGP). This number of outage workers generally falls wi thin the range (200 to 900 workers per reactor unit) reported in the GEIS for additional maintenance workers (NRC 1996). 3.4.2 REFURBISHMENT INCREMENT Performing the refurbishment activities described in Section 3.2 would necessitate increasing the PINGP staff work load by some increment. T he size of this increment would be a function of the schedule within which NMC must accomplish the work and the amount of work involved. In the GEIS (NRC 1996), NRC analyzed seven ca se study sites with respect to typical refurbishment scenarios. NRC selected a variety of nuclear plant sites that would represent the range of plant types in the United States. Then, NRC based its analyses on bounding work force estimates derived from these typical refurbishment scenarios at the case study sites. In the GEIS, NRC es timates that the most additional personnel needed to perform refurbishment activities at a pressurized water reactor would typically be 2,273 persons during a 9-month major refu rbishment outage immediately before the expiration of the initial operating license. NRC also estimates that, after the refurbishment workforce has reached it s peak, refueling would be undertaken to prepare for continued operation of the plant. In an effort to account for uncertainty surrounding workforce numbers, NRC per formed a sensitivity analysis where socioeconomic impacts were predicted in re sponse to a work force roughly 50 percent larger than the projec ted bounding case for a pressurized water reactor work force, or 3,400 workers. Having established this upper value for what would be a single event in the remainder of the life of the plant, the GEIS uses this number as the expected number of additional work ers needed per unit attributable to refurbishment. NMC analysis, including the 10 CFR 54 aging management assessments, has identified one refurbishment activity for PINGP; the steam generators for Unit 2 will be replaced (tentatively scheduled for 2013). The NMC estimate assumes a schedule similar to the Unit 1 steam generator replacem ent project. The estimated size of the workforce for this project is assumed to be similar to t hat of the workforce for the Unit 1 steam PROPOSED ACTION Page 3-18 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report generator replacement, 750 workers. Theref ore, NMC has determined that the GEIS work force size and scheduling assumptions amply bound the PINGP refurbishment work force sizes and scheduling.
Adding 750 full-time employees to the plant work force, on a similar schedule as Unit 1 steam generator replacement, would have the indi rect effect of creating additional jobs because of the multiplier effect. In the multiplier effect, each dollar spent on goods and services by a worker becomes income to the recipient who saves some but re-spends the rest. In turn, this re-spending becomes income to someone else, who in turn saves part and re-spends the rest. The number of times the final increase in consumption exceeds the initial dollar spent is called the "multiplier."
There are economic models that incorporate buying and selling linkages among regional industries and are used to estimate the impact of employee expenditures in a region of interest. However, due to the temporary nature of this project, the size of the surrounding population (2,733,326 residents within a 50-mile radius
), and the fact that most i ndirect jobs would be service related, NMC assumes that the majority of indirect workers would already be residing within the 50-mile radius and a multiplier would not be needed. 3.4.3 LICENSE RENEWAL INCREMENT Performing the license renewal activities described in Section 3.3 would necessitate increasing the PINGP staff work load by some increment. T he size of this increment would be a function of the schedule within which NMC must accomplish the work and the amount of work involved. The analysis of license renewal employment increment focuses on programs and activities for managing the effects of aging. The GEIS (NRC 1996) assumes that NRC would renew a nuclear power plant license for a 20-year period, plus the duration remaining on the current license, and that NRC would issue the renewal approxim ately 10 years prior to license expiration. In other words, the renewed license would be in effect for approximately 30 years. The GEIS further assumes that the utility would initiate surveillance, monitoring, inspections, testing, trending, and recordkeep ing (SMITTR) activities at th e time of issuance of the new license and would conduct license renewal SMITTR activities throughout the remaining 30-year life of t he plant, sometimes during full-power operation, but mostly during normal refueling and the 5- and 10-y ear in-service inspection and refueling outages (NRC 1996). NMC has determined that the GEIS scheduling assumptions are reasonably
representative of PINGP in cremental license renewal workload scheduling. Many PINGP license renewal SMITTR activities would have to be performed during outages. Although some PINGP license renewal SMITTR activities would be one-time efforts, others would be recurring periodic activities that would continue through the life of the plant. The GEIS estimates that the most additional personnel needed to perform license renewal SMITTR activities would typically be 60 persons during the 3-month duration of a 10-year in-service inspection and refue ling outage. Having es tablished this upper PROPOSED ACTION Page 3-19 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report value for what would be a single event in 20 years, the GEIS uses this number as the expected number of addition al permanent workers needed per unit attributable to license renewal. GEIS Section C.3.1.2 uses this approach in order to "...provide a realistic upper bound to potential population-driven impacts-." In reality, NMC expects to add no more than two additional permanent workers to perform all license renewal SMITTR activities.
However, in an effort to be conservative, NMC is analyzing impacts for a maximum of 60 additional permanent workers.
Therefore, NMC assumes that PINGP would require 60 addi tional permanent workers to perform all license renewal SMITTR activities and that all 60 empl oyees would migrate into the 50-mile radius.
Adding employees to the plant work force for the period of extended operation would have the indirect effect of creating additional jobs. However, considering the size of the 50-mile radius population (2, 733,326) and the fact that most indirect jobs would be service-related, NMC assumes that the majo rity of indirect workers would already be residing within the 50-mile radius.
PROPOSED ACTION Page 3-20 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report TABLE 3.1-1 TRANSMISSION LINES FR OM PINGP SUBSTATION 2.5-mile-long transmission line connection to Red Rock 1 (345-kV; Xcel Energy Line #0986)
When the PINGP generating facilities were completed in 1973, the Red Rock - Adams line described in the 1971 Environmental Report Operating License Stage (OLER) (NSP 1971) was "split" to create two new 345-kV circuits, one running north from the plant to Red Rock and one running south from the plant to Adams. The 2.5-mile-long transmission line connection runs from PINGP to the Red Rock 1 line. It shares a 250-foot-wide corridor with the PINGP-Red Rock 2 line, PINGP-Blue Lake line, and the 2.5-mile-long transmission line connection to the Adams line. PINGP to Red Rock 2 (345-kV; Xcel Energy Line #0987) The Red Rock 2 line, described in the 1973 FES, connects PINGP to the Red Rock substation in St. Paul. It is approximately 32 miles long, and shares a corridor with three other lines for approximately 2.5 miles, then with the Red Rock 1 line for the remainder of its length. PINGP to Blue Lake (345-kV; Xcel Energy Line #0976) The Blue Lake Line, described in the 1973 FES, connects PINGP to the Blue Lake substation in Scott County. It is approximately 50 miles long, and is associated with a 150-foot-wide corridor. 2.5-mile transmission line Connection to Adams (345-kV; Xcel Energy Line #0979) When the PINGP generating facilities were completed in 1973, the Red Rock - Adams line described in the 1971 OLER was "split" to create two new 345 kV circuits, one running north from the plant to Red Rock and one running south from the plant to Adams in Mower County. A 345-kV 2.5-mile-long transmission line connection to the Adams line was constructed from PINGP. This 2.5-mile-long transmission line connection shares a 250-foot wide corridor with the other 345-kV lines. PINGP to Spring Creek (161-kV; Great River Energy Line #5302) This 161-kV circuit, owned by Great River Energy, supplies power to the Red Wing, Minnesota area. It moves west from the PINGP switchyard, then turns to the southeast, extending to the Spring Creek substation, near Red Wing. The Spring Creek line is approximately 5 miles long, and runs through a 100-foot-wide corridor.
PROPOSED ACTION Page 3-21 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report TABLE 3.4-1 PINGP EMPLOYEES BY COUNTY County Number of Employees (Permanent and Contract) Percentage of Total Employees Goodhue County, Minnesota 329 48.0 Dakota County, Minnesota 139 20.3 Pierce County, Wisconsin 99 14.5 Other 118 17.2 Total 685 100.0 PROPOSED ACTION Page 3-22 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.0 PROPOSED ACTION NRC "-The report must contain a description of the proposed action, including the applicant's plans to modify the facility or its administrative cont rol procedures-. This report must describe in detail the modifications directly affecting the environment or affecting plant effluents that affect the environment-." 10 CFR 51.53(c)(2)
Nuclear Management Company (NMC) proposes that the U.S. Nuclear Regulatory Commission (NRC) renew the operating licenses for Prairie Island Nuclear Generating Plant (PINGP) Units 1 and 2 for the maximu m period currently allowable under the Atomic Energy Act and NRC's regulations (10 CFR 54.31). This action would provide the option to operate PINGP up to 20 years beyond the current operating license terms expiring on August 9, 2013 (Unit 1) and Oc tober 29, 2014 (Unit 2). Renewal would thereby enable the State of Mi nnesota, Xcel Energy and its subsidiary companies, and other participants in the wholesale power ma rket to rely on PINGP to meet future electric power needs through the period of extended operation of these generating units. In the following sections of Chapter 3, NMC presents a description of the PINGP site and activities relevant to assessments presented in Chapter 4 of this Environmental Report (ER). Section 3.1 provides a general description of plant design and operating features. Sections 3.2 th rough 3.4 describe potential cha nges to support the renewed PINGP Unit 1 and PINGP Unit 2 operating licenses.
PROPOSED ACTION Page 3-1 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.1 GENERAL PLANT INFORMATION General information about the design and operational features of PINGP from an environmental impact standpoint is available in several documents. Among the most comprehensive sources are the Final Envir onmental Statement (FES) prepared by the NRC's predecessor agency, t he U.S. Atomic Energy Commission (AEC) and the Updated Safety Analysis Report (USAR).
In 1973, the AEC issued an FES that analyzed impacts of constructing and operati ng a two-unit plant with a cooling tower-based heat dissipation system (AEC 1973). In compliance with NRC regulations, NMC routinely updates the USAR to reflect current plant design and operating features (NRC 1996). The major structures, housed faci lities, and nearby areas are shown in Figure 3.1-1.
Major site buildings include the following: Unit 1 and Unit 2 contai nment buildings that house the nuclear steam supply systems including the reactors, steam generators, reactor coolant pumps, and related equipment; The auxiliary building that houses ma jor components of the primary component cooling water system, boric acid storage tanks and pumps, and other safety-related equipment; The turbine building, where the turbine generators, main condensers, turbine plant heat exchangers, and relat ed equipment are housed; Other structures and facilities of inte rest within the site boundary include the PINGP substation, intake and plant screenhouses, intake and discharge canals, Independent Spent Fuel Storage Installation (ISFSI), four mechanical draft cooling towers, and emergency diesel generators. 3.1.1 REACTOR AND CONTAINMENT SYSTEMS PINGP is a two-unit plant utilizing pressurized water reactors. The plant was originally constructed with two pressurized light-water reactor nuclear steam supply systems and turbine generators designed an d manufactured by Westinghouse Electric Company (Scientech 2005). Initial fuel loading was completed in 1973 for Unit 1 and 1974 for Unit
- 2. Following a period of te sting, full commercial operat ion began December 16, 1973 for Unit 1 under Facility Operating Licens e Number DPR-42, and December 21, 1974 for Unit 2 under Facility Operating Lic ense Number DPR-60 (N MC 2007, p. 1.1-1).
The containment for each unit consists of tw o systems. The primar y containment is a cylindrical steel pressure vessel with a hemispherical dome and ellipsoidal bottom designed to withstand a lo ss-of-coolant accident. The secondary containment is a cylindrical shield building constructed of re inforced concrete which serves as radiation shielding for normal operation and for the loss-of-coolant condi tion. The shield building also acts as a secondary containment structure for control of containment leakage PROPOSED ACTION Page 3-2 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report (NMC 2007). The shield buildings are cylindrical (205 feet hi gh by 120 feet in diameter), each capped with a hemispheric dome (AEC 1973, p. III-1).
PINGP has a design rating of 1650 megawa tts-thermal (MWt) per reactor, which corresponds to a gross electrical output of 575 megawatts-electrical (MWe). Each reactor is capable of an ultimate therma l power output of 1721.
4 MWt, and all steam and power conversion equipment, including the turbine generat or, has the capability to generate a maximum calculated gross unit out put of 592 MWe. All plant safety systems, including containment and engine ered safeguards, were designed and originally evaluated for operation at the maximum power level of 1721.4 MWt (NMC 2007, p. 1.1-2). Unit 1's original Westingho use steam generators were replaced with Framatome-ANP designed generat ors in 2004 (AREVA 2006).
3.1.2 NUCLEAR
FUEL PINGP is licensed for low-enriched uranium-d ioxide fuel with enric hments to a nominal
5.0 percent
by weight uranium-235 and an average fuel burn-up for the peak rod that does not exceed 62,000 megawatt days per metric ton uranium (MWd/MTU). The uranium-dioxide fuel is in the form of high-d ensity ceramic pellets. Fuel rods used in the reactors consist of Zircaloy with fuel pel lets stacked inside and sealed with welded end plugs. The fuel rods are fabricated into a ssemblies designed for loading into the reactor core. The PINGP reactor cores contain 29 control rod assemblies and 121 fuel assemblies. Refueling of the reactors is performed every 20 mont hs with approximately 40 percent of the fuel being replaced during each refueling outage. PINGP has two spent fuel pools, a larger one to store spent fuel and a smaller one intended primarily to handle a spent fuel shipping cask. New racks were installed in 1981, and resulted in the curr ent pool storage capacity of 1,386 assemblies (MEQB 1991, Appendix D). The NRC has licensed an Independent Spent Fuel Storage Installation (ISFSI) at PINGP, allowing up to 48 casks.
Prior to 2003, State law lim ited the authorized use to 17 casks, but new State law enacted in 2003 now allows use of up to the 48 casks permitted by the NRC. Currently, there are 24 casks installed in the ISFSI (Minnesota Legislative Reference Library 2006). 3.1.3 COOLING AND AUXILIARY WATER SYSTEMS 3.1.3.1 Water Use Overview Water for condenser cooling is withdrawn from the Mississippi River. Water used for service water cooling, screen wash, irrigation, and domestic water supply is groundwater withdrawn from on-site wells.
Station surface water and groundwater withdrawals are governed by water appropr iation limits set by the Minnesota Department of Natural Resources (MN DNR). Under Water Appropriations Permit Number 690171, PINGP may withdraw a maxi mum of 1,200 gallons per minute (gpm) of groundwater from two on-site wells for the domestic water system. A third well PROPOSED ACTION Page 3-3 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report provides domestic and irrigation water for the Training Center.
Water Appropriations Permit Number 690172 limits withdrawal of surf ace water from the Mississippi River for condenser cooling to 630,000 gpm.
The FES related to the Prairie Island Nucl ear Generating Plant (AEC 1973) describes the original configuration of the plant's cooling water systems, which were extensively modified in the early 1980s. As designed an d initially operated, the plant withdrew cooling water from the Mississippi River (Sturgeon Lake) via a 750-foot-long intake canal that extended from the river shore line to the screen house, where a trash rack removed large debris and four (3/8-inch mesh) traveling screens (per unit) removed fish and smaller debris. A skimmer wall (barrier) at the mouth of the intake canal prevented large floating objects from entering the intake canal. The plant's heated discharge flowed into a discharge basin, from whic h it was (depending on plant operating mode) either pumped to the cooling towers or discharged to the river via an 800-foot-long
canal. The plant could be operated in any one of three modes: open cycle (once-through flow, with no cooling towers in operation), helper cycle (once-through flow with cooling towers in operation), and closed-cycle (recirculation of up to 95 percent of the cooling water flow). The plant's cooling system was heavily modi fied in the early 1980s to reduce impacts of plant operation on aquatic communities (S tone & Webster 1983). A new intake screenhouse with improved traveling screens was constructed across the mouth of intake canal. A fish return line was in stalled to convey organisms washed from the traveling screens back to the Mississippi River. A new, half-mile-long discharge canal
with a north-south orientation was created by building a 2,350-foot-long dike that paralleled the river shoreline. A new di scharge structure was built at the southern terminus of the canal, and connected to the river's edge by four underground discharge pipes. The new submerged jet discharge was intended to promote rapid mixing of the heated effluent, keep fish out of the discharge canal, and prevent recycling of warm discharge water (Stone & Webster 1983). The intake and discharge modifications were
completed in 1983. 3.1.3.2 Circulating Water System As previously discussed, PINGP withdraws water from the Missi ssippi River for its circulating water (condenser cooling) system.
Key components of the circulating water system and closely related cooling tower system are the intake screenhouse, plant screenhouse, circulating water pumps, condens ers, discharge stru cture, mechanical draft cooling towers, discharge canal, and disc harge structure, show n in Figure 3.1-1.
The PINGP cooling water intake system is designed to minimize impacts to fish populations. Aquatic organisms on the traveling screens and in the attached buckets are lifted to the level of the fish sprays and washed off into a fish collection trough within four minutes. Removal of the fish and or ganisms is accomplished on the upward travel side with a low pressure [10 pounds per square inch (psi)] inside spray when fine mesh screen is used and with a low pressure (20 psi) outside spray when coarse mesh screen is used. Debris is removed by a backsi de interior high pressure (50 psi for fine PROPOSED ACTION Page 3-4 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report mesh and 100 psi for coarse mesh) spray system. In spring and summer (April 1 - August 31), traveling screens are equipped with fine mesh (0.5 millimeter) panels (Xcel Energy 2006a). For the remai nder of the year, conventiona l screens with coarse mesh (3/8 inch) panels are employed. Trave ling screens can be operated over a range of speeds, depending on panel mesh size and debris loading. The pump supplying the 50 psi fine mesh spray is run at a higher speed to provide a 125 psi spray to supplement the 100 psi coarse mesh spray during periods of high trash loading. The separate fish and debris troughs combine to form a common trough. The fi sh and debris are then returned to the river through a buried pipe. The pipe discharges at a point approximately 1,500 feet south of the intake screenhouse. Transferring the fish downriver, outside of the influence of the coo ling water intake, serves to prevent re-impingement of weakened or disoriented fish.
The pipe is designed for velocities between 3 and 5 feet per second with higher velocities encountered for short durations.
All internal surfaces of the pipe are sm ooth to preclude abrasion damage. The pipe discharges below the mean water elevation at a depth which ensures submergence below any ice cover.
River water flows into the intake screenhous e through eight (18.5 foot by 11.2 foot) intake bays, each equipped with a trash ra ck, a 10-foot-wide traveling screen, and high/low pressure wash systems (Xcel Energy 2006a). Bypass gates permit a continuous flow in the event that traveling screens become clogged with debris (Stone &
Webster 1983). After moving through the tr aveling screens, circulating water flows down the intake canal to the plant screenhouse, where the circulating water pumps are housed. Four circulating water pumps (two per nuclear unit) supply water to the condensers for cooling. Each pump has a design capacity of 147,000 gpm, meaning the circulating water flow is approximatel y 294,000 gpm per unit (NMC 2007, pg. 11.5-1) and the total circulating water flow is appr oximately 588,000 gpm.
Smaller volumes of water are also withdrawn for its cooling water (i.e., service water) system, which supplies cooling water to a variety of feedwater pumps, air compressors, and small heat exchangers in the plant. 3.1.3.3 Circulating Water System Operating Modes After passing through the condensers, cooling water is piped to a discharge basin from which it may be (a) pumped to the cooling to wers (closed-cycle or helper cycle) or (b) allowed to flow to the discharge canal (open c ycle) via the distribution basin. If it is pumped to the cooling towers, the cooling to wer outfall may be routed back to the intake canal (closed cycle) or flow to the discharge canal (helper cycle). The distribution basin receives circulating water flow from t he discharge basin duri ng open-cycle operation and from the cooling tower return canal dur ing closed-cycle operation.
During transition periods (from closed cycle to open cycle), the dist ribution basin receives flow from both sources. The cooling tower system is comprised of fo ur towers, fans, water distribution headers and basins. Each tower has one cooling tower pump and is made up of 12 cells
grouped together (a bank).
PROPOSED ACTION Page 3-5 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report The cooling tower pumps intake water from the discharge basin and discharge into individual distribution pipes to the top of the cool ing towers. The pumps are vertical, dry pit pumps mounted so that the casing will be flooded with the water in the discharge basin at normal level. The pump motors are mounted on, and suppor ted by, the pump.
The intakes to the pumps are submerged to prevent the intake of air from any cause. Spray nozzles at the top of the cooling towers break-up the wate r stream into small streams which drop by gravity through a maze of "fill" to a basin at the base of the towers. Fans draw air up through the stream s of water and the heat of the water is carried into the atmosphere by the airstream. Fr om the cold water basin at the bottom of the towers, the water flows through the coo ling tower return canal to the distribution basin (NMC 2007). The towers are designed to accommodate the full circulating water flow of the plant and are capable of remo ving up to 96 percent of the waste heat generated by plant operation (AEC 1973).
Operation of PINGP's circulating water system is governed by spring and fall "trigger points." The spring trigger point is defined as the point in time that the daily average ambient river temperature increases to 43 degrees Fahrenheit (F) or above for five consecutive days, or April 1, wh ichever occurs first. The fall trigger point is the point at which the daily average upstream ambient ri ver temperature falls below 43 degrees F for five consecutive days. From the spri ng trigger point through the fall trigger point, PINGP is required to operate the cooling to wers as necessary to meet the following requirements: (1) the temper ature of the receiving wate r immediately below Lock and Dam No. 3 can not be raised by more than 5 degrees F above ambient, (2) the cooling water discharge can not exceed a daily aver age temperature of 86 degrees F, and (3) if the daily average ambient rive r temperature reaches 78 degr ees F for two consecutive days, all cooling towers shall be operated to the maximum extent practicable (NPDES
Permit No. MN0004006).
From the fall trigger point through March 31, the temperat ure of the receiving water immediately below Lock and Dam No. 3 can not be raised above 43 degrees F for an extended period of time. If the receiving water temperat ure exceeds this 43-degree F limit for two consecutive days, NMC must notify the Commissioner and the MN DNR.
The Commission may require NMC to operate t he cooling towers or take alternative action to meet the 43-degree F crit erion (NPDES Permit No. MN0004006). PINGP is equipped with a deicing system to prevent the formation of ice on trash racks, traveling screens, and bypass gates (Stone and Webster 1983). Warm water is
pumped from the discharge canal to the intake screenhouse via a 30-inch-diameter pipe buried below the frostline. The warm water is discharged at the bottom of the approach canal, directly in front of the intake screenhouse. 3.1.3.4 Biofouling and Scale Control PINGP uses a cleaning system to mechanically remove biofouling micro-organisms from circulating wat e r piping. The PI NGP NPDES permit provides for periodic chlorine/bromine use in the circulating water system to treat for pathogenic amoeba (see Section 4.12) and zebra mussels (NPDES Permit No. MN0004006). The cooling PROPOSED ACTION Page 3-6 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report water system (service water system), however, is treated with oxidizing biocides (chlorine and bromine) to prevent the growth of biofouling mi cro-organisms. The current PINGP NPDES permit limits the release of total residual bromine and total residual chlorine at Outfall SD 001 (combined circulat ing water and cooling water discharge) to 0.001 and 0.04 milligrams per liter (mg/L), respectively, during continuous application and 0.05 and 0.2 mg/L, respectively, during in termittent application (NPDES Permit No.
MN0004006). 3.1.3.5 Domestic Water Supply and Sanitary Wastewater Treatment NMC operates three groundwater wells to me et the domestic water needs of PINGP.
Two main wells, each equipped with 300-gp m pumps, supply the majority of the domestic water and are permitted to withdraw a total of 50 million gallons per year. The actual usage for these wells averaged approx imately 60 gpm for the years 2000 through 2005. A third well provides domestic and irrigat ion water for the Trai ning Center. This well is equipped with an 80-gpm pump and is permitted to withdraw 4.7 million gallons per year (NSP 2006). Actual use for the years 2000 through 2005 averaged 4 gpm (TtNUS 2006). The plant's sanitary wastes are directed to seven septic systems, which are pumped on varying schedules. The systems are designated as the Plant Septic (consisting of three tanks), the Warehouse 1 Holding Tank, the Guardhouse Septic, the Office Complex, the Fabrication Shop, the New Administration Building, the Environmental Lab, and the Prairie Island Training Cent er (Xcel Energy Undated). 3.1.4 RADIOACTIVE WASTE TREATMENT SYSTEMS 3.1.4.1 Liquid Radioactive Waste Systems Radioactive liquids entering the Waste Dispos al System are collected in intermediate holding tanks for determination of subsequent tr eatment. If liquids are to be released, they are first sampled and analyzed to determine the quantity of radioactivity and if it meet acceptable release criteria. The liquid wastes are then processed as required for reuse or released under controlled conditions and in accordance with applicable limits of 10 CFR 20 and the design objectives of Appendix I to 10 CFR 50 (NMC 2007).
The bulk of the radioactive liquid drained from the Reactor Coolant System is processed by the Chemical and Volume Control System recycle train, and retained inside the plant.
This minimizes liquid input to the Waste Dis posal System which processes relatively small quantities of generally low activity le vel wastes. The processed water from the waste disposal system, from which the majority of the radioactive material has been removed, may be reused or released through a monitored line to the discharge canal downstream of the coo ling towers (NMC 2007).
PROPOSED ACTION Page 3-7 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.1.4.2 Gaseous Radio active Waste Systems The gaseous radwaste system is designed to process and control the release of gaseous radioactive effluents to the site environs so that the offsite radiation dose rate does not exceed the limits specified in 10CFR20 and the design objectives of Appendix 1 to 10CFR50 are met. Waste gases are processed by one of two interconnected equipment trains. The low leve l loop provides sufficient st orage capacity for cover gases from the nitrogen blanketing system to minimize the need to vent gases which accumulate as a result of shutdown operat ions. Discharges of fission gases from the system are limited to maintenance vents, unavoidable equipment leaks, and infrequent gas decay tank releases to dispose of gas es accumulated by inflows from shutdown operations and miscellaneous vents.
Controls are provided to regulate the rate of release from these tanks through the monitored plant vent. The high level loop was designed to accumulate, concentrate, and contain fission gases at high activity concentrations from continuous purging of the volume control tanks gas space. It would
provide continuous removal of fission gases from the letdown cool ant to maintain the coolant fission gas concentrations at a low re sidual level. This loop can perform these functions and/or be used for reserve holdup capacity of low level loop gas (NMC 2007, Section 9.3). 3.1.4.3 Solid Radioactive Waste Systems The solid radiological waste system is designed to package, store, and provide shielded storage facilities for solid wastes and to allo w temporary storage prio r to shipment from the plant for off-site processing or disposal. The system is designed to meet the requirements of 10 CFR 20, 10 CFR 71, and 49 CFR 170-189.
Solid wastes consist mainly of dry active waste (DAW) such as contaminated paper, plastic, wood, metals, and spent resin. DA W may be compacted for disposal or storage or may be sent off-site for fu rther processing, such as sort ing or incineration. The by-product of such off-site processing (inciner ator ash for example) may be returned to the plant site for storage if no di sposal site is available. Contaminated metals may be compacted on-site for storage or disposal. Contaminated
metals may also be sent off-site for pr ocessing such as decontamination or metal melting. Spent resin originates in any of several syst em ion exchangers. Spent resin is flushed to a resin shipping liner for disposal or off-si te processing. Alternatively, resin may be placed in on-site storage if a disposal site is not available. NMC plans to continue managing its low-level radioactive waste in compliance with all applicable regulations established by state and federal agencies.
Solid wastes received at disposal sites mu st meet the requirem ents of 10 CFR 61 relating to waste form and classification as well as disposal site-specific regulations (NMC 2007, Section 9.4).
PROPOSED ACTION Page 3-8 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.1.5 NON-RADIOACTIVE WASTE MANAGEMENT As outlined in Xcel Energy Environmental Po licy, PINGP is committed to conducting its business in an environmentally responsible manner (Xcel Energy 2006b). One element of this policy is ensuring that wastes gener ated by business activities/operations are managed in compliance with applicable regulati ons and in a manner pr otective of the environment and human health. It also incl udes, where appropriate, minimizing the creation of waste, especially hazardous waste.
Xcel Energy's Waste Management Guidanc e Manual (Xcel Energy 2006c) assists PINGP employees in the identification of regulated wastes.
It includes directions for selecting waste collection containers, storage and labeling requirements, and transport and disposal procedures. Training, em ergency planning, and record keeping requirements associated with waste management are also de scribed. Additional topics on waste regulations, employee responsibilities, and handling a regulatory inspection are included.
Proper management of regulated waste fa lls under three federal agencies: the Environmental Protection Agency (EPA), the Occupational Safety and Health
Administration (OSHA), and the Department of Transportati on (DOT). Congress began the process of waste regulation with the passage of the Resource Conservation and Recovery Act of 1976 (RCRA). This ac t authorized the EPA to write regulations providing for a comprehensive management system for hazardous wastes. It also imposed 'cradle to grave' responsibility on the generator of a hazardous waste, meaning Xcel Energy never loses liability for its waste. As a result, Xcel Energy does not select waste disposal vendors on cost alone, but also evaluates and selects transportation and disposal companies that demonstrate co mpetence in managing hazardous wastes.
RCRA authorizes states to develop their own waste regulations. The State of Minnesota has authorization to manage their hazardous waste management programs and have developed additional regulations making them more restrictive than federal requirements (MN Rules Chapter 7045).
OSHA is involved in waste management through the Hazard Communication (HAZCOM) Standard, requiring th at employers inform and train workers in proper handling of hazardous substances. Under the Hazardous Waste Operations and Emergency Response (HAZWOPER) Standar d, OSHA established training requirements for workers that respond to releases of hazardous substances.
The DOT considers hazardous wastes a subs et of hazardous materials, which means many regulated wastes are subject to DOT requirements during shipment. DOT regulations contain packaging specifications, container marking and labeling requirements, emergency reporti ng requirements, release re sponse requirements, and a complex tracking system using shipping papers and manifests. DOT also requires training for employees with re sponsibility for the shipment of hazardous materials.
Non-radioactive waste is produced from plant maintenance, cleaning, and operational processes. The majority of the waste generated consists of non-hazardous waste oil, PROPOSED ACTION Page 3-9 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report oil-filled equipment used in operations and maintenance, and oily debris. Universal waste defined by Minnesota Pollution Control Agency (MPCA) includes lighting ballasts, polychlorinated biphenyl (PCB) small capacit ors, mercury containing devices and batteries, antifreeze, circuit boards, elec tronics, photographic negatives, cathode ray tubes (CRTs), alkaline batteries, and non-TC LP fluorescent and HID lamps, common to any industrial facility, comprise a majority of the remaining waste volumes generated.
Hazardous waste routinely makes up a sma ll percentage of the total waste generated and consists of spent and off-specification (e.g. shelf-life expired) chemicals, laboratory chemical wastes, Freon-contaminated oil, and occasional project-specific wastes. As outlined in the company environmental policy, Xcel Energy is committed to considering pollution prevention in busine ss planning and decisio n-making processes. Pollution prevention reduces wastes, which in turn reduces regulatory burdens, reduces liability, and saves money. It also helps conserve valuable resources and protects human health and the environment. Pollution prevention is achieved by utilizing the Waste Management Hierarchy fo r reducing waste generation.
This hierarchy prioritizes waste reduction though source reduction, r euse/recycle, and treatment and disposal, respectively (Xcel Energy 2006c). 3.1.6 TRANSMISSION FACILITIES 3.1.6.1 History/Background When PINGP was built, its generating and transmission facilities were owned and operated by Northern States Power, a regulated utility with headquarters in Minneapolis, Minnesota. In May 2000, Northern States Power transferred its authorization to operate PINGP to NMC, a contract/oper ations firm that currently ov ersees the operation of two nuclear plants in Minnesota. Northern Stat es Power continued to operate and maintain the PINGP transmission lines when the responsibility for managing the PINGP generating facilities was transferr ed to NMC. Therefore t he discussion that follows on the planning, construction, and modification of PINGP transmission facilities in the 1970s and 1980s applies to Northern States Power, whereas the discussion of current maintenance and vegetation management practices applies to Xcel Energy.
Before PINGP was built, a 345-kilovolt (k V) line was installed between the Red Rock substation in St. Paul and the Adams substa tion in Mower County, 74 miles south of Prairie Island (NSP 1971, p. II-25). This line was designed to pass near the proposed PINGP site and link to the new plant once bui lt, thereby providing connections between the plant and St. Paul (Red Rock) and between the plant and southeastern Minnesota (Adams). When PINGP was built, the Red Rock - Adams line was divided, and the two new "halves" connected to PINGP by means of a 2.5-mile-long corridor that runs to the plant substation.
The FES noted that two new 345-kV lines were required to connect the plant to the regional electric transmission syst em (AEC 1973, p. III-1).
One new line was built from PINGP Unit 1 to the Blue Lake substation in Scott County; another was built from PINGP Unit 2 to the Red Rock substation in south St. Paul. The new line from Unit 1 to PROPOSED ACTION Page 3-10 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report the Blue Lake substation required constructi on of a new corridor to the Inver Grove substation, in Dakota County; the rema ining segment, between Inver Grove and the Blue Lake substation, was routed along an exis ting corridor. The entire length of the new line from Unit 2 to the Red Rock substation was routed along an existing corridor.
In total, Northern States Power built 78 m iles of new line to deliver power to the transmission system (AEC 1973). Because NSP was able to take advantage of existing transmission corridors, it was only necessary to acquire 33 miles of new right-of-way. NRC defines the transmission corridors of concern for license renewal as those constructed for the specific purpose of connecting the plant to the transmission system [10 CFR 51.53(c)(3)(ii)(H)]. NRC further elaborates in the GEIS and guidance that the corridors of concern are those that were "constructed between the plant switchyard to its connection with the existing transmission system." Supplement 1 to Reg. Guide 4.2 (NRC 2000) recommends that applicants "specifically identify those transmission lines that were identified in the construction permit review as being constructed to connect the plant to the transmission system." AEC's 1968 construction permit review for PINGP predated the 1970 enactment of the National Envir onmental Policy Act. The FES related to the Prairie Island Nuclea r Generating Plant (AEC 1973) was concerned with impacts of "-the continuation of construction permits-and the issuance of operating licenses-for the startup and operation of the PINGP" and considered impacts of both construction and operatio n of the plant. Two 345-k V transmission lines, PINGP - Blue Lake and PINGP - Red Rock 2, were considered in the 1973 FES and will therefore be considered for transmission-rela ted impacts in Chapter
- 4. The two 2.5-mile-long transmission line connections built to connect PINGP to the Red Rock 1 and Adams lines will also be analyzed. In addition, the 161-kV line owned by Great River Energy that runs from PINGP to Spring Creek is included in the scope of this analysis. 3.1.6.2 Current Syst em Configuration The output of PINGP is deliver ed to the substation just north of the generating facilities with 345-kV and 161-kV switchyards (NMC 2007, Section 8.2). Five transmission lines leave the switchyards via three transmission corridors: One corridor, running west, contains the 2.5-mile-long transmission line connection to Red Rock 1 and Blue Lake 345-kV lines. A second corridor, running west, contains the Red Rock 2 and the 2.5-mile-long transmission line connection to Adams 345-kV lines. A third corridor, running south, cont ains the Spring Creek 161-kV line.
These five transmission lines connect PING P to the regional tr ansmission system (NMC 2007, Section 8.2.1). The current transmission system is summarized in Table 3.1-1.
Figure 3.1-1 shows the layout of the transmission lines leav ing the PINGP substation.
Figure 3.1-2 presents the routes of the five in-scope transmission lines.
PROPOSED ACTION Page 3-11 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report Northern States Power and Great River Energy designed and constructed the PINGP transmission lines in accordance with industr y guidance that was current when the lines were built. Ongoing surveillance and maintenance of PINGP-related transmission facilities ensure continued conformance to design standards. Section 4.10 examines the conformance of the lines with the National Electrical Safety Code requirements on line clearance to limit shock from induced currents (IEEE 1997).
Xcel Energy uses a variety of methods to ensure that transmissi on corridors are kept free of brush and fast-growing trees that could interfere with transmission facilities (e.g., towers, conductors, sub-stations). Bec ause transmission corridors cross areas with different kinds of terrain and vegetation, Xc el Energy employs an Integrated Vegetation Management (IVM) approach that includes bo th mechanical and chemical control methods. IVM involves the judicious use of a range of vegetation management treatments including tree removal, pruning, mowing, an d chemical (herbicide) application (Xcel Energy 2005).
Great River Energy also uses an IVM program to enhance wildlife along power line rights-of-way. This effort includes the use of low-
volume biodegradable herbicides to remove unwanted woody species, while leaving behind the grasses, wildflowers, and low-growing trees preferred by butterflies, songbirds, wild turkey, and deer (Great River Energy 2006). The goal of Xcel Energy's IVM program is to develop site-specific, environmentally-sensitive, and cost-effective solutions to vegetation management near transmission and distribution facilities. The pr imary objective is to keep transmission facilities clear of tall-growing trees and brush that could grow too close to conductors and interfere with electricity transmission. This is accomplished with routine ve getation management on each transmission circuit that is conduct ed on an established maintenance cycle. Xcel Energy has adopted the "Wire zone/Border zone" concept to allow for different types and heights of vegetation in transmissi on corridors (Xcel Energy 2005). The goal is to manage vegetation in rights-of-way so as to establish a "wire zone" directly underneath towers and conductors with low-growing forbs and grasses and a "border
zone" (from outside edge of wire zone to edge of right-of-way) with slow-growing shrubs and trees that do not grow high enough to interf ere with transmission structures. Areas outside the border zone are peri odically inspected for tall "
danger trees" (dead, dying, or diseased trees that could fall and interfere with transmission lines).
These trees are removed expeditiously, outside of the normal maintenance cycle. Xcel Energy has adopted guidelines that govern the use of her bicides in its transmission corridors (Xcel Energy 2005). Contract ors engaged in vegetat ion management must submit plans/proposals to Xcel Energy
's Vegetation Management representative detailing any planned use of herbicides. Pr oduct labels and Material Safety Data Sheets must be supplied to the Vegetati on Management representat ive along with the treatment plan. In addition to this oversight of site-specific vegetation management plans, Xcel Energy's Vegetation Management Guidelines (provided to all contractors engaged in vegetation management) prohibit the use of herbi cides outside of right-of-way boundaries and instruct contractors to discontinue the use of herbicides PROPOSED ACTION Page 3-12 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report immediately if a property owner objects to their use, pending the resolution of any issues. Xcel Energy plans to maintain these transmission lines, which are integral to the larger transmission system, indefinitely. These transmission lines will remain a permanent part of the transmission system even after PINGP is decommissioned. 3.1.6.3 Avian Mortality R esulting from Collisions with Transmission Lines NRC (1996) noted in the GEIS that "No relative ly high collision mortality is known to occur along transmission lines associated wi th nuclear power plants in the United States other than the Prairie Island plant in Minnesota."
The statement refers to a 5-year study in which bird carcasses were collected along two transmission corridors originating at PINGP (Goddar d 1977; 1978; 1979). The corri dors were searched from the substation just north of the PINGP generating facilities to the transmission towers nearest the Vermillion River (Goddard 1977), a dist ance of about 1.5 miles. A total of 453 bird carcasses representing 53 species were found during the 5-year period. About 64 percent of the carcasses were found alon g the 2,500-foot east-we st portion of the corridors slightly northwest of the PINGP substation (Figure 3.
1-1). This section of the corridors is perpendicular to the bird migr ation corridor along the Mississippi River. Other avian collision studies have also found that transmission lines at right angles to avian flight paths are associated with greater collisions (Goddard 1979). As a result of the criminal prosecution of the Moon Lake El ectric Association, Inc., a Utah-based electric power company, for electroc ution of protected birds, the U.S. Fish and Wildlife Service (FWS) and several po wer companies began to discuss a method for addressing the avian electrocution pr oblem (USDOJ 2002). A Memorandum of Understanding (MOU) between the FWS and Xcel Energy, the first of its type completed in the U.S., has been in effect sinc e 2002 (NSPCM & FWS 2002). The MOU was created to establish procedures and policies dealing with mi gratory birds that may be present on NSP property, and outlined the development of an Avian Protection Plan.
Xcel Energy submits semi-annual reports to the FWS summarizing activities covered under the MOU. The Avian Protection Plan for PINGP and associated transmission lines is in development.
Very few bird carcasses have been observed at PINGP or along PINGP-associated transmission lines since 1978, but systematic sear ches or formal avian collision studies have not been conducted. Therefore, the curr ent extent of collision-related mortality and a comparison of avian mortality at PI NGP to other nuclear plants have not been evaluated. However, the GEIS noted that the mortality at PING P may not be unique, and may simply reflect the fact that surve ys were performed. NRC (1996) further states that "the issue is whether collision mortality is large enough to cause long-term reductions in bird populations." Based on a literature search, NRC (1996) concluded that avian collisions with transmission lines did not significantly reduce species populations, and bird collisions with transmission lines associated with license renewal would not cause long-term reduction in bird p opulations, and thus, collision mortality is of small significance.
PROPOSED ACTION Page 3-13 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.1.7 MAINTENANCE, OPERATION, AND INSPECTION NMC implements programs to maintain, inspect, test, and monitor the performance of plant equipment. These programs are desig ned to meet several requirements:
- 10 CFR 50, Appendix B (Quality Assuranc e), Appendix R (Fire Protection), and Appendices G and H, Reactor Vessel Materials;
- 10 CFR 50.55a, American Society of Mechan ical Engineers, Boiler and Pressure Vessel Code,Section XI, In-service Inspection and Testing Requirements;
- 10 CFR 50.65, the maintenance rule, and
- Maintain water chemistry in accordance with Electric Power Research Institute (EPRI) guidelines.
Additional programs include those implemented to meet Technical Specification surveillance requirements, those implemented in response to NRC generic communications, and various periodic maintenance, testing, and inspection procedures necessary to manage the effects of aging on structures and comp onents. Certain program activities are performed during the operation of the uni ts, while others are performed during scheduled ref ueling outages. Current maintenance, operation, and inspection activities will continue and be expanded to include programs for managing the effects of aging.
PROPOSED ACTION Page 3-14 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.2 REFURBISHMENT ACTIVITIES NRC "- The report must contain a description of - the applicant's plans to modify the facility or its administrative control procedures-. This report must describe in detail the modifications directly affecting the environment or affecting plant effluents that affect the environment-." 10 CFR 51.53(c)(2) "The environmental report must contain analyses of -refurbishment activities, if any, associated with license renewal-" 10 CFR 51.53(c)(3)(ii) "- The incremental aging management activities carried out to allow operation of a nuclear power plant beyond the original 40 year license term will be from one of two broad categories: ... and (2) major refurbishment or replacement actions, which usually occur fairly infrequently and possibly only once in the life of the plant for any given item-." NRC 1996 NMC has addressed refurbishment activities in this environmental report in accordance with NRC regulations and complementary in formation in the NRC GEIS for license renewal (NRC 1996). NRC requirements for the renewal of operating licenses for nuclear power plants include the preparation of an integrated plant assessment (IPA)
(10 CFR 54.21). The IPA must identify and list systems, structures, and components subject to an aging management review. Items that are subject to aging and might require refurbishment include, for example, piping, supp orts, and pump casings (see 10 CFR 54.21 for details), as well as those that are not subject to periodic replacement. In turn, NRC regulations for implementing the National Environmental Policy Act require environmental reports to describe in detail and assess the environmental impacts of refurbishment activities such as planned modifications to systems, structures, and components or plant effluents [10 CFR 51.53 (c)(2)]. Resource categories to be evaluated for impacts of refurbishment in clude terrestrial resources, threatened and endangered species, air quality, housing, public utilities and water supply, education, land use, transportation, and historic and archaeological resources. The GEIS (NRC 1996) provides helpful information on the scope and preparation of refurbishment activities to be evaluated in th is environmental report. It describes major refurbishment activities that utilities might perform for license renewal that would necessitate changing administrative control procedures and modifying the facility. The GEIS analysis assumes that an applicant wo uld begin any major refurbishment work shortly after NRC grants a renewed license and would complete the activities during five outages, including one major outage at the end of the 40th year of operation. The GEIS refers to this as the refurbishment period. GEIS Table B.2 (NRC 1996) lists license renew al refurbishment activities that NRC anticipated utilities might undertake. In identifying these activi ties, the GEIS intended to encompass actions that typically take place only once, if at all, in the life of a nuclear plant. The GEIS analysis assumed that a utility would undertake these activities solely for the purpose of extending plant operations beyond 40 years, and would undertake PROPOSED ACTION Page 3-15 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report them during the refurbishment period. The GEIS indicates that many plants will have undertaken various refurbishment activities to support the current license period, but that some plants might undertake such tasks only to support extended plant operations.
Examples of refurbishment activities incl ude pressurized water re actor steam generator replacement and boiling water reactor reci rculation piping replacement when these activities are carried out to ensure safe operat ions for 20 additional years. The GEIS assumes that refurbishment activities woul d take place within the 10 years prior to current license expiration and would culminate in a major outage immediately prior to the extended (license renewal) term. Because the situation at PINGP is consistent with this example, NMC is analyzing Unit 2 steam generator replacement in this environmental report as a refurbishment acti vity, pursuant to 10 CFR 51.53(c)(3)(ii).
The new steam generators would be manufactured at AREVA's Chalon Saint-Marcel plant. Delivery of the st eam generators would take place in May 2013 with installation following in September 2013 (AREVA 2006).
The refurbishment outage is expected to last approximately 80 days. Like the 2004 Unit 1 steam generator replacement, the steam generators would arrive by barge afte r journeying from France and traveling up the Mississippi River. A temporary construction area is planned to be located approximately 100 yards northwest of the turbi ne building. Several temporary buildings would be built, including a facility for prepar ing the steam generators, office space for construction contractors, and a decontamination building.
Warehouse(s) would also be built on site and would rema in after the steam generator replacement outage. Any construction would occur within the existi ng plant boundaries.
There would be no clearing of previously-undisturbed areas. No road improvements would be required because the steam generators would arrive via barge and be offloaded to a self-
propelled nuclear transporter capable of traveling on existing site roads without damage. NMC estimates that 750 worker s would be required to perform the steam generator replacement and standard outage maintenance and refueling.
PROPOSED ACTION Page 3-16 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report 3.3 PROGRAMS AND ACTIVITIES FOR MANAGING THE EFFECTS OF AGING NRC "-The report must contain a description of - the applicant's plans to modify the facility or its administrative control procedures-. This report must describe in detail the modifications directly affecting the environment or affecting plant effluents that affect the environment-." 10 CFR 51.53(c)(2) "-The incremental aging management activities carried out to allow operation of a nuclear power plant beyond the original 40 year license term will be from one of two broad categories: (1) SMITTR actions, most of which are repeated at regular intervals -." NRC 1996 (SMITTR is defined in NRC 1996 as surveillance, monitoring, inspections, testing, trending, and recordkeeping.)
The IPA required by 10 CFR 54.21 ident ifies the programs and inspections for managing aging effects at PINGP. These progr ams are described in the Prairie Island Nuclear Generating Plant License Renewal Application, Appendix B, Aging Management Programs. Other than implementation of programs and inspections identified in the IPA, NMC has no plans to modify administrative controls that are associated with license renewal.
PROPOSED ACTION Page 3-17 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report
3.4 EMPLOYMENT
3.4.1 CURRENT
WORKFORCE NMC employs approximately 685 permanent and long-term contract employees at PINGP, a two-unit facility.
Approximately 83 percent of the employees live in Goodhue and Dakota Counties, Minnesot a, and Pierce County, Wisconsin. Table 3.4-1 presents the number of employees that reside in each of these counties. The remaining employees are distributed across 21 counties in Minnesota and Wisconsin, with numbers ranging from 1 to 47 employees per county. A few employees live outside of these two states.
PINGP is on a 20-month refueling cycle.
During refueling outages, site employment increases above the permanent work force by as many as 925 workers for temporary duty (based on 2003 to 2006 normal refueling outage workforces at PINGP). This number of outage workers generally falls wi thin the range (200 to 900 workers per reactor unit) reported in the GEIS for additional maintenance workers (NRC 1996). 3.4.2 REFURBISHMENT INCREMENT Performing the refurbishment activities described in Section 3.2 would necessitate increasing the PINGP staff work load by some increment. T he size of this increment would be a function of the schedule within which NMC must accomplish the work and the amount of work involved. In the GEIS (NRC 1996), NRC analyzed seven ca se study sites with respect to typical refurbishment scenarios. NRC selected a variety of nuclear plant sites that would represent the range of plant types in the United States. Then, NRC based its analyses on bounding work force estimates derived from these typical refurbishment scenarios at the case study sites. In the GEIS, NRC es timates that the most additional personnel needed to perform refurbishment activities at a pressurized water reactor would typically be 2,273 persons during a 9-month major refu rbishment outage immediately before the expiration of the initial operating license. NRC also estimates that, after the refurbishment workforce has reached it s peak, refueling would be undertaken to prepare for continued operation of the plant. In an effort to account for uncertainty surrounding workforce numbers, NRC per formed a sensitivity analysis where socioeconomic impacts were predicted in re sponse to a work force roughly 50 percent larger than the projec ted bounding case for a pressurized water reactor work force, or 3,400 workers. Having established this upper value for what would be a single event in the remainder of the life of the plant, the GEIS uses this number as the expected number of additional work ers needed per unit attributable to refurbishment. NMC analysis, including the 10 CFR 54 aging management assessments, has identified one refurbishment activity for PINGP; the steam generators for Unit 2 will be replaced (tentatively scheduled for 2013). The NMC estimate assumes a schedule similar to the Unit 1 steam generator replacem ent project. The estimated size of the workforce for this project is assumed to be similar to t hat of the workforce for the Unit 1 steam PROPOSED ACTION Page 3-18 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report generator replacement, 750 workers. Theref ore, NMC has determined that the GEIS work force size and scheduling assumptions amply bound the PINGP refurbishment work force sizes and scheduling.
Adding 750 full-time employees to the plant work force, on a similar schedule as Unit 1 steam generator replacement, would have the indi rect effect of creating additional jobs because of the multiplier effect. In the multiplier effect, each dollar spent on goods and services by a worker becomes income to the recipient who saves some but re-spends the rest. In turn, this re-spending becomes income to someone else, who in turn saves part and re-spends the rest. The number of times the final increase in consumption exceeds the initial dollar spent is called the "multiplier."
There are economic models that incorporate buying and selling linkages among regional industries and are used to estimate the impact of employee expenditures in a region of interest. However, due to the temporary nature of this project, the size of the surrounding population (2,733,326 residents within a 50-mile radius
), and the fact that most i ndirect jobs would be service related, NMC assumes that the majority of indirect workers would already be residing within the 50-mile radius and a multiplier would not be needed. 3.4.3 LICENSE RENEWAL INCREMENT Performing the license renewal activities described in Section 3.3 would necessitate increasing the PINGP staff work load by some increment. T he size of this increment would be a function of the schedule within which NMC must accomplish the work and the amount of work involved. The analysis of license renewal employment increment focuses on programs and activities for managing the effects of aging. The GEIS (NRC 1996) assumes that NRC would renew a nuclear power plant license for a 20-year period, plus the duration remaining on the current license, and that NRC would issue the renewal approxim ately 10 years prior to license expiration. In other words, the renewed license would be in effect for approximately 30 years. The GEIS further assumes that the utility would initiate surveillance, monitoring, inspections, testing, trending, and recordkeep ing (SMITTR) activities at th e time of issuance of the new license and would conduct license renewal SMITTR activities throughout the remaining 30-year life of t he plant, sometimes during full-power operation, but mostly during normal refueling and the 5- and 10-y ear in-service inspection and refueling outages (NRC 1996). NMC has determined that the GEIS scheduling assumptions are reasonably
representative of PINGP in cremental license renewal workload scheduling. Many PINGP license renewal SMITTR activities would have to be performed during outages. Although some PINGP license renewal SMITTR activities would be one-time efforts, others would be recurring periodic activities that would continue through the life of the plant. The GEIS estimates that the most additional personnel needed to perform license renewal SMITTR activities would typically be 60 persons during the 3-month duration of a 10-year in-service inspection and refue ling outage. Having es tablished this upper PROPOSED ACTION Page 3-19 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report value for what would be a single event in 20 years, the GEIS uses this number as the expected number of addition al permanent workers needed per unit attributable to license renewal. GEIS Section C.3.1.2 uses this approach in order to "...provide a realistic upper bound to potential population-driven impacts-." In reality, NMC expects to add no more than two additional permanent workers to perform all license renewal SMITTR activities.
However, in an effort to be conservative, NMC is analyzing impacts for a maximum of 60 additional permanent workers.
Therefore, NMC assumes that PINGP would require 60 addi tional permanent workers to perform all license renewal SMITTR activities and that all 60 empl oyees would migrate into the 50-mile radius.
Adding employees to the plant work force for the period of extended operation would have the indirect effect of creating additional jobs. However, considering the size of the 50-mile radius population (2, 733,326) and the fact that most indirect jobs would be service-related, NMC assumes that the majo rity of indirect workers would already be residing within the 50-mile radius.
PROPOSED ACTION Page 3-20 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report TABLE 3.1-1 TRANSMISSION LINES FR OM PINGP SUBSTATION 2.5-mile-long transmission line connection to Red Rock 1 (345-kV; Xcel Energy Line #0986)
When the PINGP generating facilities were completed in 1973, the Red Rock - Adams line described in the 1971 Environmental Report Operating License Stage (OLER) (NSP 1971) was "split" to create two new 345-kV circuits, one running north from the plant to Red Rock and one running south from the plant to Adams. The 2.5-mile-long transmission line connection runs from PINGP to the Red Rock 1 line. It shares a 250-foot-wide corridor with the PINGP-Red Rock 2 line, PINGP-Blue Lake line, and the 2.5-mile-long transmission line connection to the Adams line. PINGP to Red Rock 2 (345-kV; Xcel Energy Line #0987) The Red Rock 2 line, described in the 1973 FES, connects PINGP to the Red Rock substation in St. Paul. It is approximately 32 miles long, and shares a corridor with three other lines for approximately 2.5 miles, then with the Red Rock 1 line for the remainder of its length. PINGP to Blue Lake (345-kV; Xcel Energy Line #0976) The Blue Lake Line, described in the 1973 FES, connects PINGP to the Blue Lake substation in Scott County. It is approximately 50 miles long, and is associated with a 150-foot-wide corridor. 2.5-mile transmission line Connection to Adams (345-kV; Xcel Energy Line #0979) When the PINGP generating facilities were completed in 1973, the Red Rock - Adams line described in the 1971 OLER was "split" to create two new 345 kV circuits, one running north from the plant to Red Rock and one running south from the plant to Adams in Mower County. A 345-kV 2.5-mile-long transmission line connection to the Adams line was constructed from PINGP. This 2.5-mile-long transmission line connection shares a 250-foot wide corridor with the other 345-kV lines. PINGP to Spring Creek (161-kV; Great River Energy Line #5302) This 161-kV circuit, owned by Great River Energy, supplies power to the Red Wing, Minnesota area. It moves west from the PINGP switchyard, then turns to the southeast, extending to the Spring Creek substation, near Red Wing. The Spring Creek line is approximately 5 miles long, and runs through a 100-foot-wide corridor.
PROPOSED ACTION Page 3-21 Prairie Island Nuclear Generating Plant License Renewal Application Appendix E - Environmental Report TABLE 3.4-1 PINGP EMPLOYEES BY COUNTY County Number of Employees (Permanent and Contract) Percentage of Total Employees Goodhue County, Minnesota 329 48.0 Dakota County, Minnesota 139 20.3 Pierce County, Wisconsin 99 14.5 Other 118 17.2 Total 685 100.0 PROPOSED ACTION Page 3-22