April 2006 3-1 NUREG-1817

3.0 Site Layout and Plant Parameter Envelope

The proposed Grand Gulf early site permit (ESP) site is located within the current boundaries of

the Grand Gulf site, which contains Grand Gulf Nuclear Station (GGNS), Unit 1. As noted in

Chapter 1, System Energy Resources, Inc. (SERI) did not define a particular reactor design and |

facilities layout in its ESP application. Instead, SERI used a plant parameter envelope (PPE) to |

provide bounds for assessing the environmental impact and determining site suitability. SERI’s |

application (SERI 2005a) encompasses construction and operation of one or more new nuclear |

units generating as much as 8600 MW(t) or 3000 MW(e) output. The site layout and existing

facilities are discussed in Section 3.1. The PPE itself is presented in Appendix I and discussed

in Section 3.2. The electrical transmission system is discussed in Section 3.3.

3.1 External Appearance and Site Layout

The Grand Gulf ESP site, which lies within the 850-ha (2100-ac) confines of the Grand Gulf

site, is situated on the eastern shore of the Mississippi River (Figure 2-1). The existing reactor

unit at the GGNS (Unit 1) is a boiling-water reactor that went online in 1985. The reactor unit |

generates 3898 MW(t) or 1353 MW(e). It is cooled by a natural draft cooling tower and

auxiliary mechanical draft tower located to the southwest of the containment and powerblock

buildings. Makeup water for the cooling system is brought from radial wells along the

Mississippi River via underground pipeline; discharge water is also piped to the Mississippi

River via underground pipeline. The switchyard, which was originally constructed to support

power from two units, lies to the east of the containment and powerblock buildings. |

Originally, the Grand Gulf site was licensed by the Nuclear Regulatory Commission (NRC) for |

the construction of two units, although only one unit was completed and is currently operating.

A portion of the containment building for Unit 2 was built before that unit was abandoned. This

structure is located north of Unit 1. An area adjacent to Unit 1 was cleared and excavated for

construction of a cooling tower for Unit 2, but it also was abandoned. These features are visible

in the aerial view of the facilities shown in Figure 3-1, which also shows the main features of the

GGNS facilities and the pipeline route to the Mississippi River. The existing facilities and

structures of the GGNS facility cover 68 ha (169 ac) of the Grand Gulf site (SERI 2005a). The |

Grand Gulf ESP site, much of which has been disturbed previously, is located outside the area

occupied by the existing GGNS facility and its support structures.
Plant Description

NUREG-1817 3-2 April 2006

Figure 3-1. Aerial Photo of the Grand Gulf Nuclear Station

3.2 Plant Parameter Envelope

| As described in Subpart A of Title 10 of the Code of Federal Regulations (CFR) Part 52

| (10 CFR 52.17), the applicant for an ESP need not provide a detailed design of a reactor or

reactors and the associated facilities, but must provide sufficient bounding parameters and
Plant Description

April 2006 3-3 NUREG-1817

characteristics of the reactor or reactors and the associated facilities so that an assessment of

site suitability can be made. Consequently, the ESP application may refer to a PPE as a

surrogate for a nuclear power unit or units and associated facilities. |

A PPE is a set of values of plant design parameters that an ESP applicant expects will bound

the design characteristics of the reactor or reactors that might be constructed at a given site. 

The PPE values are a surrogate for actual reactor design information. Analysis of

environmental impacts based on a PPE approach permits an ESP applicant to defer the

selection of a reactor design until the construction permit (CP) or combined construction permit |

and operating license (combined license or COL) stage. The PPE reflects upper or lower |

bounds of the values for each parameter that it encompasses rather than the characteristics of

any specific reactor design. Appendix I lists the complete PPE values that are provided in the

SERI ESP application.

Reactor Designs Considered in the PPE

In its ESP application, SERI used a composite of values from seven reactor designs to develop

the bounds of its PPE (SERI 2005a). The values in this EIS are not design-specific. Rather, |

they are used to determine the environmental impact of any reactor design that falls within the

bounding values used in this environmental impact statement (EIS). These reactor designs |

include the following five light water reactor and two gas-cooled reactor types: 

 C Advanced Canada Deuterium Uranium Reactor (ACR-700) – This reactor, developed by

Atomic Energy Canada Limited, is an evolutionary extension of the CANDU 6 plant |

using very slightly enriched uranium fuel and light water coolant.

 C Advanced Boiling Water Reactor (ABWR) – This reactor, developed by General Electric

Company, is a standardized plant that has been certified under U.S. Nuclear Regulatory |

Commission (NRC) requirements (10 CFR Part 52, Appendix A). The ABWR is fueled |

with slightly enriched uranium and uses a light water cooling system.

 C Advanced Pressurized Water Reactor (AP1000) – This is an earlier version of the |

AP1000 reactor final design developed by Westinghouse Electric Company and under |

review by the NRC, using slightly enriched uranium and a light water cooling system. |

This design is not the AP1000 that has been certified under U.S. Nuclear Regulatory |

Commission (NRC) requirements (10 CFR Part 52, Appendix A); therefore, this design |

will be referred to as the “surrogate AP1000.”

 C Economic Simplified Boiling Water Reactor (ESBWR) – This reactor, developed by

General Electric Company, is fueled with slightly enriched uranium and uses a light

water cooling system.
Plant Description

NUREG-1817 3-4 April 2006

 C International Reactor Innovative and Secure (IRIS) next-generation pressurized water

reactor (PWR) – This reactor, under development by a consortium led by Westinghouse

Electric Company, is a modular light water reactor.

 C Gas Turbine Modular Helium Reactor (GT-MHR) – This reactor, developed by General

Atomics, is a modular helium-cooled graphite-moderated reactor.

 C Pebble Bed Modular Reactor (PBMR) – This reactor, developed by PBMR (Pty) Ltd., is a

modular graphite-moderated helium-cooled gas turbine reactor.

| The ABWR and AP1000 designs have been certified by the NRC in accordance with 10 CFR

| Part 52, Subpart B. The other designs are in the pre-application stage.

| SERI (or another applicant) would not be required to use any of these designs if it chooses to

| submit a CP or COL application, but the characteristics of the reactor ultimately chosen would

| have to be demonstrated to be within the bounds of the PPE for the assessment contained in

this EIS to be applicable.

Review Approach

NUREG-1555, Environmental Standard Review Plan (ESRP) (NRC 2000), and review standard

RS-002, Processing Applications for Early Site Permits (NRC 2004), provide guidance to the

NRC staff to help ensure a thorough, consistent, and disciplined review of any ESP application. 

The staff’s June 23, 2003 response to comments received on draft RS-002 (NRC 2003) provide

additional insights on the staff’s expectations and approach to the review of an application

employing the PPE approach.

| Because PPE values were used as a surrogate for design-specific values, the staff expected

SERI to provide sufficient information for the staff to develop a reasonable independent

assessment of potential impacts to specific environmental resources. In some cases, the

| design-specific information called for in the ESRP were not provided in the SERI ESP

application because it did not exist or was not available. Therefore, the NRC staff could not

apply the ESRP guidance in those review areas. In those cases, the NRC staff used its

experience and judgment to adapt the review guidance in the ESRP and to develop

assumptions necessary to evaluate impacts to certain environmental resources to account for

this missing information. These assumptions are discussed in the appropriate sections of

this EIS.
Plant Description

April 2006 3-5 NUREG-1817

Because the SERI PPE values do not reflect a specific design, they were not reviewed by the

NRC staff for correctness. However, the NRC staff made a determination that the application

was sufficient to enable the staff to conduct its required environmental review and that the PPE

values are not unreasonable for consideration by the staff when making its finding on the |

application in accordance with 10 CFR 52.18. During its environmental review, the staff used |

its judgment to determine whether SERI provided sufficient information for the staff to perform

its independent assessment of the environmental impacts of construction and operation of a

new nuclear unit or units. The staff considered the PPE values to be bounding parameters. 

Therefore, the staff’s evaluation serves as a bounding estimate of the potential environmental

impacts resulting from constructing and operating one or more new nuclear units at the |

ESP site.

Throughout the Grand Gulf ESP environmental report, SERI (2005a) provides: |

(1) Commitments to address certain issues in the design, construction, and operation of the

facility

(2) Statements of planned compliance with current laws, regulations, and requirements

(3) Commitments to future activities and actions that it will take should it decide to apply for a

CP or COL

(4) Descriptions of SERI’s estimate of the environmental impacts resulting from the

construction and operation of a new nuclear unit or units on the Grand Gulf ESP site 

(5) Descriptions of SERI’s estimates of future activities and actions of others and the likely

environmental impacts of those activities and actions that would be expected should SERI

decide to apply for a CP or COL.

The activities described include, but are not limited to, such actions as:

 C Considering the results of testing and monitoring during the development of a CP or |

COL application

 C Complying with NRC and other agency regulations, including obtaining appropriate

permits from other agencies

 C Taking actions to mitigate adverse environmental impacts, including following industry or

company standards, practices, or protocols

 C Addressing certain issues at the CP or COL stage that were not addressed in the ESP

application.
Plant Description

(a) The listing is not intended to be a complete list of the commitments described in the environmental

report.

| (b) Necessary comm itments, activities, and actions may change over time as new laws are enacted and

| regulations are issued.

NUREG-1817 3-6 April 2006

Some of these future actions are those that SERI would be required to implement because they

are currently required by law, and others are actions that SERI has indicated that they would

implement without the legal obligation to take such actions. Those matters considered by the

staff in determining the level of impacts to a resource are discussed throughout this EIS and are

listed in Appendix J.(a)

| The staff performed its evaluation of the impacts of constructing and operating one or more

new nuclear units at the ESP site assuming that these commitments, activities, and actions

would be undertaken by SERI and others during future licensing activities.(b) As discussed

previously, the staff developed assumptions necessary to evaluate impacts to certain

environmental resources to account for missing detailed information. In addition to other

sources of information obtained independently, the staff considered the commitments, future

activities and actions, and estimates of expected environmental impacts that were identified by

SERI in its environmental report and listed in Appendix J, as well as the PPE values listed in

| Appendix I, when developing the inputs and assumptions used in the NRC staff’s independent

| review of the environmental impacts of constructing and operating one or more new units on the

Grand Gulf ESP site.

In addition, as a result of the staff’s environmental review of the SERI ESP application, the staff

determined that conditions or limitations on the ESP may be necessary in specific areas, as set

forth in 10 CFR 52.24. Therefore, the staff identified when and how assumptions and bounding

values limit its conclusions on the environmental impacts to a particular resource, where

appropriate.

| During the review of a CP or COL application referencing an ESP, the staff would assess the

environmental impacts of the construction and operation of a specific plant design. If the

environmental impacts addressed in the ESP EIS are found to be bounding by the staff, no

| additional analysis of these impacts would be required, even if the ESP applicant employed the

PPE approach. However, environmental impacts not considered or not bounded at the ESP

| stage would be assessed at the CP or COL stage. The inputs and assumptions that were used

| or considered during the staff’s evaluation of the ESP application (listed in Appendixes I and J)

| would provide the basis for the staff’s verification review in which the staff must determine

whether or not a specific design in a CP or COL application falls within the PPE.
Plant Description

April 2006 3-7 NUREG-1817

3.2.1 Facility Water Use

Raw water would be needed to support construction and operation of the Grand Gulf ESP

facility. The installation of an additional well would likely be required for construction purposes,

such as concrete batch facility operation, dust suppression, and sanitary needs. The normal

heat sink (NHS), service water system (SWS), and ultimate heat sink (UHS) have operational

water needs, that would be met using raw water withdrawn from the Mississippi River. Other

water sources, such as wells, may be used to supply water for general site purposes including

potable, sanitary, and landscape maintenance.

In the PPE (see Appendix I), SERI specified average and maximum raw water makeup for the

Grand Gulf ESP facility. The PPE provides bounding constraints on portions of facility water

use. Other constraints on facility water use are based on site-specific information. This EIS

assesses the impact of facility water use bounded by the PPE and site-specific constraints. 

The following sections describe the water uses of the Grand Gulf ESP facility and the

associated facility water treatment systems. The cooling systems are described in more detail

in Section 3.2.2.

3.2.1.1 Facility Water Consumption

The dominant water use is makeup water for the NHS. That makeup water replaces water lost

by evaporation, drift, and blowdown. The PPE (see Appendix I) lists the average makeup water

flow as 3020 L/s (47,900 gpm) and the maximum makeup water flow as 4920 L/s (78,000 gpm). 

Average and maximum blowdown are listed as 807 L/s (12,800 gpm) and 2500 L/s

(39,000 gpm). SERI proposes to discharge the NHS blowdown to the Mississippi River. The

SWS water obtained from the Mississippi River would be routed to the NHS system for reuse, |

and the flows are therefore bounded by the flows identified for the NHS. The UHS would |

supply cooling water to safely shut down and cool down the facility in the event of an |

emergency. SERI’s proposed UHS design is an engineered water basin with mechanical draft

cooling towers. During emergency conditions, the UHS would draw water from that water basin

and there would not be a demand for water from the local environment.

3.2.1.2 Facility Water Treatment

SERI discusses facility water treatment in Section 3.3.2 of the environmental report

(SERI 2005a). The water supply system would provide water for the circulating water system, |

NHS, SWS, UHS, demineralized water system, fire protection system, and other miscellaneous

raw water supply needs. The sources of water for the Grand Gulf ESP facility would be a new

well in the Catahoula aquifer and a new intake on the Mississippi River. Filtration equipment,

such as clarifiers, would remove suspended solids from the river water. Clarified, filtered, and

chemically treated water would be required. The specific methods and chemicals required for
Plant Description

NUREG-1817 3-8 April 2006

the prevention of corrosion, biological fouling, and for process-water treatment are not known at

this time. Discharge of chemical effluents from water treatment processes would be limited by

| a National Pollutant Discharge Elimination System (NPDES) permit issued by the Mississippi

Department of Environmental Quality (MDEQ).

3.2.2 Cooling System

The Grand Gulf ESP facility would have several different cooling systems. The largest heat

| load would be dissipated by the NHS. The SWS would have a far smaller heat rejection load,

and the UHS designed heat rejection load is only required to safely shut down the facility. SERI

has not yet finalized a detailed design for the cooling water systems. However, based on the

location of the proposed site, SERI has considered the potential for three cooling system

designs for the NHS: mechanical draft, natural draft, and a wet-dry hybrid design. While it can

be expected that a wet-dry hybrid system would have lower water demands than a natural draft

or mechanical draft tower, wet-dry hybrid towers were not included in the PPE (Appendix I) and

were not considered further in the staff’s review. The staff’s discussion of the various heat-

| dissipation alternatives at the Grand Gulf ESP site is provided in Section 8.3.1 of this EIS.

3.2.2.1 Description and Operational Modes

Waste heat is a by-product of power generation at a nuclear power plant. The NHS is an

integral part of such power generation. The NHS comprises a closed-loop circulating water

system, pumps, water basin, and cooling towers. The circulating water system pumps water

through the main condenser and then to the cooling towers. Heat is transferred to the water in

the condenser and is dissipated to the atmosphere by evaporation. The main condenser for

each unit of a new facility would reject heat to the atmosphere at a rate of 3140 MW(t)

(10.7 x 109 Btu/hr) during normal full-power operation, according to the PPE (see Appendix I).

During the heat-dissipation process, evaporation of water increases the dissolved solids in the

NHS cooling water. To limit the concentration of solids in the NHS cooling water, a portion of

the water is discharged from the NHS system as blowdown. In addition to the blowdown and

evaporative losses, a small percentage of water in the form of droplets (drift) is lost from the

cooling towers. SERI states that water pumped from the Mississippi River would be used to

replace water lost by evaporation, drift, and blowdown. Blowdown water would be returned to

the Mississippi River via a new outfall, thereby dissipating a small portion of the rejected heat to

the Mississippi River. In the PPE (see Appendix I), SERI provides bounding values for water

and energy fluxes for the NHS. The NHS values follow:

| C Maximum blowdown flow would be 2500 L/s (39,000 gpm). 

| C Maximum blowdown temperature would be 38°C (100°F). 
Plant Description

April 2006 3-9 NUREG-1817

 C Maximum evaporation rate would be 2500 L/s (39,000 gpm). |

 C Maximum makeup flow value would be 5000 L/s (78,000 gpm). |

According to SERI, the SWS represents less than 1 percent of the NHS heat rejection load and

is included in the NHS bounding values in the PPE.

SERI (2005a) proposes a closed-loop UHS for the Grand Gulf ESP facility. The UHS system |

would comprise pumps, heat exchangers, a dedicated water basin, and cooling towers. The

basin would be required to maintain an adequate supply of water for 30 days of emergency |

operation. The UHS supplies the cooling water to structures, systems, and components

required to safely shut down and cool down the nuclear power plant under normal operations,

anticipated operational occurrences, and accident conditions. SERI (2005a) has provided |

bounding values for water and energy fluxes for the UHS. The UHS values follow:

 C Maximum blowdown flow would be 110 L/s (1700 gpm). |

 C Maximum blowdown temperature would be 35°C (95°F). |

 C Maximum evaporation rate would be 110 L/s (1700 gpm). |

According to these values, the UHS represents less than 1 percent of the NHS heat rejection

load.

3.2.2.2 Component Descriptions

The following sections describe the intake, discharge, and heat-dissipation systems. |

Intake System

SERI (2005a) states that water would be withdrawn from the Mississippi River through a |

proposed intake structure on the river shore, at or near the GGNS barge slip location. Water

would be withdrawn from an embayment via piping connected to pumps and equipment housed

in an intake pumping station in the vicinity of the embayment. Dredging would be required to

form the embayment. The environmental report (SERI 2005a) shows the location of proposed |

intake, suction pipelines, and intake screens. To minimize erosion by river currents and to

protect the integrity of the embayment, the slopes would be covered by riprap or other similar

means. Screens would be mounted at the entrance to each suction pipeline to minimize uptake

of aquatic biota and river debris. The intake screens would be designed so that the average

velocity at the screens would be less than 0.15 m/s (0.5 ft/s), as required by 40 CFR 125.84, to |

limit organism mortality from impingement and entrainment. SERI would design the

embayment to limit the amount and rate of sediment deposition and littoral debris carried into

the embayment.
Plant Description

NUREG-1817 3-10 April 2006

Discharge System

Effluent from the Grand Gulf ESP facility (including blowdown, excess service water, sanitary

| waste, filter process waste, radwaste effluent, and miscellaneous drain effluent) would be

combined with the existing discharges from GGNS Unit 1 facility downstream from the

| embayment and intake. SERI (2005a) states that an outfall diffuser, located on the shoreline,

would be used to enhance distribution and cooling of the effluent, thereby limiting thermal

| impact in the area of the discharge. SERI (2005a) states that the effluent discharge outfall

would be located approximately 150 to 180 m (500 to 600 ft) downstream of the intake screens,

and at approximately 9 m (30 ft) above the low water reference plane for the Mississippi River. 

| The maximum discharge from all sources would be 2630 L/s (41,700 gpm). The NHS cooling

tower blowdown would be the major contributor to the total discharge flow, and its return

temperature is estimated at 38°C (100°F).

Heat Dissipation Systems

Heat dissipation from the NHS, SWS, and UHS would occur through the use of cooling towers

| and blowdown to the Mississippi River. Wet cooling towers were proposed by SERI (2005a) for

the NHS and UHS. The SWS heat dissipation was incorporated into the NHS. Two different

options for NHS cooling towers were evaluated for the Grand Gulf ESP facility. The first

consisted of four natural draft cooling towers and the second used four 20-cell linear

mechanical draft cooling towers. In both cases, the total heat rejection rate and the bounding

values of blowdown flow rate and blowdown water temperature are defined in the PPE

(Appendix I).

3.2.3 Radioactive Waste Management System

| Liquid, gaseous, and solid radioactive waste management systems would be used to collect

and treat the radioactive materials that are produced as a by-product of operating the proposed

| unit or units on the Grand Gulf ESP site. These systems would process radioactive liquid,

gaseous, and solid effluents to maintain releases within regulatory limits and to levels as low as

is reasonably achievable (ALARA) before being released to the environment. Waste

processing systems would be designed to meet the design objectives of 10 CFR Part 50,

Appendix I (Numerical Guides for Design Objectives and Limiting Conditions for Operation to

Meet the Criterion “As Low as is Reasonably Achievable” for Radioactive Material in LightWater-Cooled Nuclear Power Reactor Effluents). Radioactive material in the reactor coolant

would be the primary source of gaseous, liquid, and solid radioactive wastes in light water

reactors. Radioactive fission products build up within the fuel as a consequence of the fission

| process. These fission products would be contained in the sealed fuel rods, but small

quantities escape the fuel rods and contaminate the reactor coolant. Neutron activation of the

primary coolant system would also be responsible for coolant contamination.
Plant Description

April 2006 3-11 NUREG-1817

The SERI ESP application did not identify specific radioactive waste management systems for |

new facilities constructed at the Grand Gulf ESP site. The PPE concept was used to provide an

upper bound on liquid radioactive effluents, gaseous radioactive effluents, and solid radioactive

waste releases (SERI 2005a). For liquid releases, a composite release from the following |

reactors was used to bound the releases: two ABWR units, two surrogate AP1000 units, and |

four ACR-700 units. With regard to gaseous releases, the bounding releases were determined |

using two ABWR units, two surrogate AP1000 units, eight GT-MHR modules, four ACR-700 |

units, and six IRIS units (SERI 2005b). Bounding gaseous effluent releases are found in |

Table 3.0-7 of the Grand Gulf ESP environmental report (SERI 2005a). Bounding liquid effluent |

releases are found in Table 3.0-8 of the environmental report (SERI 2005a). |

The bounding total annual volume of solid radioactive waste is estimated at 540 m3/yr |

(1.9 x 104 ft3/yr) with a bounding total amount of radioactive material of 2 x 1014 Bq/yr

(5400 Ci/yr) as found in the PPE (SERI 2005a). |

3.2.4 Nonradioactive Waste Management

SERI has not finalized design of nonradioactive waste management systems yet. These

systems include cooling water and auxiliary boiler blowdown that may contain water-treatment

chemicals or biocides, water-treatment wastes, floor and equipment drain effluent, storm water

runoff, laboratory waste, trash, hazardous waste, effluent from the sanitary sewer system,

miscellaneous gaseous emissions, and liquid and solid effluent. Nonradioactive liquid waste |

effluents would be regulated under the NPDES permit process and would require a permit from |

the MDEQ.

3.2.4.1 Effluents Containing Chemicals or Biocides

Chemicals are typically used to control water quality, scale, corrosion, and biological fouling. 

The chemical concentrations within effluent streams from a new facility would be controlled

through engineering, operational, and administrative controls in order to meet NPDES

requirements at the time of construction and operation.

3.2.4.2 Sanitary System Effluents

SERI (2005a) states that a permanent sanitary waste system would be provided for the |

operational phase of the Grand Gulf ESP facility. Industrial materials, such as chemistry

laboratory waste, would be excluded from the sanitary waste system. The chosen sanitary

waste system design would incorporate state-of-the-art sewage treatment and disposal

technologies to treat domestic waste only and it would comply with future expected NPDES

permit requirements.
Plant Description

NUREG-1817 3-12 April 2006

3.2.4.3 Other Effluents

Nonradioactive gaseous emission results from operating auxiliary boilers and from testing and

operating the standby power system, which may use diesel and/or gas turbine generators. 

These emissions commonly include particulates, sulfur oxides, carbon monoxide, hydrocarbons

and nitrogen oxides. Gaseous releases would comply with Federal, State, and local emissions

standards.

Chemical waste from laboratory drains, equipment decontamination, and chemical additives

would be collected in chemical waste sumps or approved chemical storage units. Chemical

drainage system waste would be monitored, treated, and released in accordance with an

approved NPDES permit, or otherwise disposed. Discharges from the chemical drainage

system would comply with applicable Federal, State, and local standards in place during

operation of a new facility. Hazardous nonradioactive waste would be treated and disposed

of in accordance with all applicable Federal, State, and local regulations.

Storm water from structures constructed at the Grand Gulf ESP site would typically flow into

major drainage courses and finally to Hamilton Lake, which is hydraulically connected to the

Mississippi River. The design of the storm water systems for a new facility would comply with

NPDES storm water regulations administered by MDEQ.

Other nonradioactive waste (such as paper, metals, and garbage) would be disposed in

accordance with applicable regulations. Nonradioactive effluent would be treated, controlled,

and discharged or disposed as required to meet Federal, State, and local regulations and

guidelines.

3.3 Transmission System

| The ESP site is adjacent to the GGNS Unit 1 facility and wholly contained within the property

| boundary of the Grand Gulf site. The Grand Gulf site is linked to load centers by a system of

transmission lines in the Entergy Mississippi, Inc. (EMI) electric system. The EMI electric

system consists of interconnected hydro, fossil-fuel, and nuclear power plants that supply

electrical energy over a 500/230/115 kV transmission system. EMI owns the GGNS switchyard

where the GGNS Unit 1 facility is connected to two transmission lines. The two lines are the

| C 40.3-km (25.2-mi) long, single-circuit 500-kV line that connects to the Baxter-Wilson

Extra High Voltage Substation 

| C 69.8-km (43.6-mi) long, single-circuit 500-kV line that connects to the Franklin Extra

High Voltage Substation. 
Plant Description

April 2006 3-13 NUREG-1817

In addition to the length, the power transmission line right-of-way widths and areas of these |

transmission lines are listed in Table 3-1. Electrical energy from GGNS Unit 1 is transmitted by |

the 500-kV lines, which existed when the GGNS Unit 1 facility was built (SERI 2005a). A |

separate distribution line (single-circuit 115 kV) runs from the Port Gibson substation to the

GGNS switchyard to provide offsite power to GGNS. The staff assumes that this line would be

sufficient to service any new units at the ESP site without modification. Therefore, this line

and its right-of-way are not considered further. |

Table 3-1. Existing Transmission Line Rights-of-Way to the Grand Gulf Site |

Right-of-Way Voltage

Length

km (mi)

Average Width

m (ft)

Area |

ha (ac)

Baxter-W ilson 500 kV 40.3 (25.2) 61 (200) 248 (612) |

Franklin 500 kV 69.8 (43.6) 61 (200) 428 (1057) |

Total 110.7 (68.8) 675 (1669)

(a) |

(a) Difference from 1575 in SERI environmental report (2005) due to rounding. |

Source: SERI 2005a

SERI (2005a) states that the power transmission and distribution system existing at the time of |

startup and operation of a new facility would be relied upon to distribute the power generated by |

the facility. A study of the existing system conducted by SERI concluded that the existing

system is adequate for an additional 1311 MW(e) generating capacity assuming that

modifications and upgrades are made to equipment in the GGNS switchyard (SERI 2005a). |

SERI (2005a) states that the maximum generating capacity of the proposed new units is |

approximately 3000 MW(e). If 3000 MW(e) generating capacity were installed, the existing

transmission lines would have to be upgraded or additional transmission lines would be

required. Assuming that a new facility at the Grand Gulf ESP site would be a merchant

generator, procedures for requesting connection to the transmission system are set forth in the

Federal Energy Regulatory Commission standard interconnection procedures and agreement |

called out in 18 CFR 35.28(f), “Standard Generator Interconnection Procedures and

Agreement,” as described below.

The Federal Energy Regulatory Commission process starts when the interconnection customer, |

in this case SERI, submits an interconnection request to EMI, the transmission provider. When |

the interconnection request is determined to be valid, the transmission provider and

interconnection customer have a scoping meeting to discuss alternative interconnection options

and exchange information. On the basis of this meeting, the interconnection customer

designates its point of interconnection, and one or more alternative point(s) of interconnection.
Plant Description

NUREG-1817 3-14 April 2006

Following the scoping meeting, the transmission provider conducts an interconnection feasibility

study to evaluate the feasibility of the proposed interconnection to the transmission system. 

This study includes a power flow and short circuit analysis. The interconnection feasibility study

is followed by an interconnection system impact study that focuses on the impact of the

interconnection on the reliability of the transmission system.

Finally, the transmission provider conducts an interconnection facilities study to specify and

estimate the cost of the equipment, engineering, procurement, and construction work needed to

implement the conclusions of the interconnection system impact study in accordance with good

utility practice to physically and electrically connect the interconnection facility to the

transmission system. These studies are conducted by the transmission provider, but the

interconnection customer pays for the studies.

SERI has not submitted an interconnection request to EMI. However, the staff assumes that

the process for obtaining any additional transmission services required would be completed

prior to submission of an application for construction and operation of a new facility at the

Grand Gulf ESP site. In addition, the staff assumes that the Grand Gulf ESP facility connection

with the transmission system would be similar to the GGNS Unit 1 facility connection and would

| make use of existing transmission line rights-of-way to the extent possible. Additional land

might be required, if only to widen existing rights-of-way. Land use in the existing transmission

| line rights-of-way is described in Table 3-2.

| Table 3-2. Land Use in the Existing Transmission Line Rights-of-Way to the Grand Gulf Site

| Right-of-Way Agriculture

Developed

Nonresidential Residential Undeveloped

Water or

Wetlands

Baxter-W ilson 23.9% 0.4% 4.5% 62.8% 8.3%

Franklin 9.4% 0.0% 0.0% 86.3% 4.3%

Total 14.7% 0.2% 1.7% 77.7% 5.8%

Notes: U.S. Geological Survey land-cover classes have been aggregated for presentation purposes.

Rounding may affect totals.

| Source: Vogelmann et al. 2001

3.4 References

10 CFR Part 50. Code of Federal Regulations, Title 10, Energy, Part 50, “Domestic Licensing

of Production and Utilization Facilities.”

10 CFR Part 52. Code of Federal Regulations, Title 10, Energy, Part 52, “Early Site Permits,

Standard Design Certifications, and Combined Licenses for Nuclear Power Plants.”
Plant Description

April 2006 3-15 NUREG-1817

18 CFR Part 35. Code of Federal Regulations, Title 18, Conservation of Power and Water

Resources, Part 35, “Filing of Rate Schedules and Tariffs,” Section 28(f), “Standard Generator

Interconnection Procedures and Agreement.”

40 CFR Part 125. Code of Federal Regulations, Title 40, Protection of Environment, Part 125, |

“Criteria and Standards for the National Pollution Discharge Elimination System.” |

System Energy Resources, Inc. (SERI). 2005a. Grand Gulf Site Early Site Permit Application. |

Revision 2, Jackson, Mississippi. Available at http://www.nrc.gov/reading-rm/adams.html,

Accession No. ML052780449.

System Energy Resources, Inc. (SERI). 2005b. Letter dated November 4, 2005 from |

G.A. Zinke to Nuclear Regulatory Commission, “Response to Request for Additional

Information Regarding the Grand Gulf Early Site Permit Draft Environmental Impact Statement.” |

Available at http://www.nrc.gov/reading-rm/adams.html, Accession No. ML060190548. |

U.S. Nuclear Regulatory Commission (NRC). 2000. Standard Review Plans for Environmental

Reviews for Nuclear Power Plants. NUREG-1555, Office of Nuclear Reactor Regulation, 

Washington, D.C. Available at http://www.nrc.gov/reading-rm/doccollections/nuregs/staff/sr1555/.

U.S. Nuclear Regulatory Commission (NRC). 2003. Response to comments on Draft RS-002,

Processing Applications for Early Site Permits. Available at http://www.nrc.gov/readingrm/adams.html, Accession No. ML031710698.

U.S. Nuclear Regulatory Commission (NRC). 2004. Processing Applications for Early Site

Permits. RS-002, Washington, D.C. Available at http://www.nrc.gov/reading-rm/adams.html,

Accession No. ML040700236.

Vogelmann, J.E., S.M. Howard, L. Yang, C.R. Larson, B.K. Wylie, and N. Van Driel. 2001. |

“Completion of the 1990s National Land Cover Data Set for the Conterminous United States |

from Lansat Thematic Mapper Data and Ancillary Data Sources.” Photogrammetric |

Engineering and Remote Sensing 67:650-652. |