Prepared for: Great River Energy Stanton, North Dakota



# Proposal for Information Collection Stanton Station

ENSR Corporation December 2006 Document No.:10735-002-400Prepared for: Great River Energy Stanton, North Dakota



# Proposal for Information Collection Stanton Station

_________________________________ Prepared By: Brian P. O’Neil

_________________________________ Reviewed By: Jean Decker

ENSR Corporation December 2006 Document No.:10735-002-400December, 2006 ii Document No.: 10735-002-400 

## Contents

1.0 EXECUTIV E SUMM ARY.......................................................................................................... ................. 1-1

2.0 INTRO DUCTIO N............................................................................................................... ......................... 2-1

2.1 Goals, Process, and Timing of the Rule......................................................................................... 2-3

2.2 CDS Sc hedule................................................................................................................... .............. 2-3

2.3 Specific Goals of this PIC..................................................................................................... ........... 2-4

2.4 Review of Docum ent Organi zation................................................................................................ . 2-4

3.0 SOURCE WATER BO DY INFORM ATION.............................................................................................. . 3-1

3.1 Source Water Body Physical Descr iption and Flow In formatio n ................................................... 3-1

4.0 TECHNOLOGIES, OPERATIONAL, AND RESTORATION MEASURES ............................................. 4-1

4.1 In-place Technologies, Op erational M easures ............................................................................... 4-1
4.1.1 Review of Existing Technologies and Operational Measures .......................................... 4-1
4.1.2 Restoration M easures ....................................................................................................... 4-5
4.1.3 Performance Es timates ..................................................................................................... 4-5

4.2 Potential Technologies, Operational Me asures, and Restorat ion Measur es................................ 4-5
4.2.1 Review of Te chnologies .................................................................................................... 4-5
4.2.2 Review of Operati onal Measur es...................................................................................... 4-9
4.2.3 Review of Restorat ion Measur es ...................................................................................... 4-9
4.2.4 Estimate of Technology and Operational Measures Costs and Effectivenes s ............... 4-9
4.2.5 USEPA’s Appraisal of Technologi es............................................................................... 4-10

4.3 Selection of Proposed Technologies, Operat ional and Restorat ion Measur es .......................... 4-10

5.0 HISTORICAL STUDY REVIEW .................................................................................................... ............ 5-1

5.1 Historical Biological and Physic al Data ........................................................................................ .. 5-1

5.2 Assessment of Data Sufficiency ................................................................................................. .... 5-4

6.0 AGENCY CO NSULTATI ONS ....................................................................................................... ............ 6-1

6.1 Section 316(b)-Specif ic Consul tations.......................................................................................... .. 6-1

6.2 Other Relevant Consultations................................................................................................... ...... 6-1

7.0 PROPOSED COMP LIANCE A PPROACH............................................................................................... 7-1

7.1 Outline of CD S Activities...................................................................................................... ........... 7-1

7.2 Review of CD S Appr oach ......................................................................................................... ...... 7-1

7.3 Schedul e....................................................................................................................... ................... 7-2

8.0 SAMPLI NG PLAN .............................................................................................................. ....................... 8-1December, 2006 iii Document No.: 10735-002-400 

## List of Tables

Table 1 Summary of the Circumstance s at Stanton Station .................................................................... 4-2

Table 2 Estimated CWIS Performance Goal: 80 to 95 Percent Reduction in Impingement Mortality (IM) ................................................................................................................. ............... 4-5

Table 3 Primary Assessment of Mi tigation Meas ures.............................................................................. 4-6

Table 4 Assessment of Data Sufficiency................................................................................................. . 5-5



## List of Figures

Figure 1 Site Locat ion Map .............................................................................................................. .......... 3-3
Figure 2 Close-up View of CWIS Loca tions .............................................................................................. 3- 4
Figure 3 Photographs of Cooling Wate r Intake Stru cture ......................................................................... 4-3
Figure 4 Fish Species Identified in the Garrison Reach, 1991 to 2003.................................................... 5-2
Figure 5 Summary of Fish Collected by NDG&F at Stanton Stat ion 1997-20 04 ..................................... 5-3



## Appendices

Appendix A – Technology Review

Appendix B – EPA Cost Estimate

Appendix C – Sampling Plan

Appendix D – Bibliography of Sources Us ed for Source Water Body Review

Appendix E – Agency Consultation DocumentationDecember 2006 1-1 Document No.: 10735-002-400 

## 1.0 EXECUTIVE SUMMARY

Great River Energy’s Stanton Stati on (GRE) is subject to the impinge ment mortality performance goals under the Clean Water Act’s Section 316(b) Phase II Rule (rule ). This Proposal for Information Collection (PIC) is developed as part of GRE’s obligations under the Phase II rule.

The Stanton Station is located on the Missouri River about 15 miles downstream of Garrison Dam, which controls flow in the river. M ean annual flow at the dam is 21, 041 cubic feet per second (cfs) 1 Stanton Station has one generating unit, with a rating of 188 MW. Norm al plant operations utilizin g the two main circulating water pumps and one auxiliary pump results in a flow of 240.3 cfs (107,800 gpm or 155 MGD). When the additional auxiliary pump is operating, the flow to the fa cility is 257.6 cfs (115,600 gpm or 166 MGD). Since average daily withdrawal exceeds the 50 MGD threshold, Stanton Station is subject to the Phase II Rule. However, reduction in entrainment is not a performance goal for these intakes since the intake rate is below the regulatory applicability threshold of 5 percent of the mean daily flow of the Missouri River at this location.

U.S. Environmental Protection Agency (USEPA) identified the St anton Station as being a facility that had to comply with both impingement and entrainment reducti on requirements. USEPA has estimated that fine-mesh wedgewire screens installed near the shor eline will be effective at reduci ng impingement mortality consistent with the rule’s goals. USEPA also has assumed that entrainment reduction would be necessary and estimated that the screens could be installed at a total capital co st of $0.99 million. Howeve r, USEPA’s guidance states that if a facility determines it must only comply with impingement reduction r equirements, the corresponding USEPA estimated cost can be calculated by dividing U SEPA’s original cost estimate by 2.148. Dividing $0.99 million by 2.148 results in an USEPA cost estimate for the Stanton Station of $0.46 million. This is the cost estimate that should be used for co mparison and cost-cost/c ost-benefit analyses.

This PIC provides a focused review of available mitigation technologies and c oncludes that no single reasonable measure exists to mitigate impingement mortal ity cost-effectively beyond that provided by the current configuration. In particular, each technology has either been found to be of limited feasibility and effectiveness or of “significantly greater” cost than the benefit to local fisheries that could be realized by its installation and operation. For this reason, GRE propo ses to pursue the rule’s Compliance Option 5 based on the Cost-benefit test. GRE proposes to use existing data collected from the Missouri River and its environs as well as data that were collected through an Impingem ent Mortality Study to support the Comprehensive Demonstration Study (CDS). As a critical component of the CDS, potential retrofit technologies will be evaluated in detail to document both technical and ec onomical feasibility. GRE believes that the application and outcome of the Cost-benefit test wi ll demonstrate that the cost of installation of any of the available technologies would be significantly higher than any be nefit that might result to the local fishery.

The proposed component elements of the CDS are listed and a tentative schedule for the CDS completion and the North Dakota Pollutant Discharge Elimination System (NDPDES) permit renewal are defined within this PIC for Stanton Station.

1 Between 1993 – 2002.December 2006 2-1 Document No.: 10735-002-400 

## 2.0 INTRODUCTION

Stanton Station has one generating unit rated at 188 MW. This base loaded unit had an average annual net generation of 1,241,062 MWh from 1998-2003, which amounts to approximately an 80 percent capacity factor. Normal plant operations utilizing both main circulating water pumps and one auxiliary pump results in a flow of 240.3 cfs (107,800 gpm or 155 MGD). When the additional auxiliary pump is operating, the total flow to the facility is 257.6 cfs (115,600 gpm or 166 MGD).

The Stanton Station operates one generating unit that draws cooling water directly from the Missouri River. Because the total intake capacity of the Stanton St ation exceeds 50 million gallons per day (MGD), an evaluation of impingement potential and reduction options is required. Reduction in entrainment is not a performance goal for these intakes since the intake rate is below 5 percent of the mean daily flow of the Missouri River at this location 2

.
The goals of this PIC for Stanton include the following:

• Address the requirements of the Code of F ederal Regulations (CFR), Title 40, Section 125.95(b)(1); and

• Facilitate the compliance process by explaining GRE’s proposed approach.

40 CFR Section 125.95(b)(1) describes the PIC requirements as follows:

You must submit to the Director for review and comm ent a description of the information you will use to support your Study. The Proposal for Information must be submitted prior to the start of information collection activities, but you may initiate such activi ties prior to receiving comment from the Director. The proposal must include:

(i) A description of the proposed and/or implem ented technologies, operational measures, and/or restoration measures to be evaluated in the Study;
(ii) A list and description of any historical studies characterizing impingement mortality and entrainment and/or physical and biological conditions in the vicinity of the cooling water intake structures and their relevance to this proposed St udy. If you propose to use existing data, you must demonstrate the extent to which the data are repr esentative of current conditions and that the data were collected using appropriate qualit y assurance/quality control procedures;
(iii) A summary of any past or ongoing consultations with appropriate Federal, State, and Tribal fish and wildlife agencies that are relevant to this St udy and a copy of written comments received as a result of such consultations; and
(iv) A sampling plan for any new field studies you propose to conduct in order to ensure that you have sufficient data to develop a scientifically valid estimate of impingement mortality and entrainment at your site. The sampling plan must document all methods and quality assurance/quality control procedures for sampling and data analysis. The sampling and data analysis methods you propose must be appropriate for a quantit ative survey and include consideration of the methods used in other studies performed in the source waterbody. The sampling plan must include a description of the study area (including the area of in fluence of the cooling water intake structure(s)),

2 The mean average daily flow at the Bismarck USGS gauging station is 22,490 cfs. Five percent of the mean average daily flow i s

1,125 cfs which is more than four times the intake capacity of the Stanton CWIS, which is 258 cfs.December 2006 2-2 Document No.: 10735-002-400 and provide a taxonomic identification of the sampl ed or evaluated biological assemblages (including all life stages of fish and shellfish).
The following tabulation provides the section of the PIC where each of the above mentioned regulatory requirements are presented.

Regulatory Requirement PIC Section § 125.95(b)(1)(i) – Review of Measures and Technologies 3.0 § 125.95(b)(1)(ii) – Historical Studies 4.0 § 125.95(b)(1)(iii) – Agency Consultations 5.0 § 125.95(b)(1)(iv) – Proposed Sampling Plan 7.0

The Phase II Rule allows for significant discretion by the North Dakota Department of Health (NDDH) during the implementation process. In fact, the Rule allows for flexibility in the compliance approach taken at a facility by including several specific criteria a ssociated with assessing compliance including:

• Which species and life stages to base the compliance assessment;

• Whether to base the assessment on numbers of individuals or biomass;

• The specifics of estimating the Calculation Baseline condition;

• The averaging period to use in estimating th e Calculation Baseline or assessing compliance;

• The ability to discount “unavoidable, episodi c impingement or entrainment events” in the assessment of performance;

• The specific design parameters (e.g., slot size) for the CWIS;

• The need for, and nature of, peer review for assessment of restoration and/or monetized benefits;

• The need for additional information collection to support the CDS;

• The nature of the Technology Installation and Operation Plan;

• The nature of Approved Technology (i.e., Compliance Option 4);

• The definition of “significantly greater” under site-specific Best Tech nology Available (BTA) (Compliance Option 5); and

• The timing of the component reports of the CDS.

GRE believes that this level of discretion allows NDDH to oversee a focused and efficient compliance program to:

• Assess the current performance of the CW IS and operation/restoration measures;

• Review the alternative measures to determine those that are feasible and cost effective;

• If appropriate, implement co st-effective measures; and

• Develop a CDS within the context of one of the Rule’s Compliance Options.

Toward this end, GRE has prepared this PIC that both addresses the requirements of the Rule and defines GRE’s recommended Phase II compliance pr ogram for the Stanton Station.December 2006 2-3 Document No.: 10735-002-400 

### 2.1 Goals, Process, and Timing of the Rule
The EPA has produced final regulations under Clean Wa ter Act Section 316(b) t hat establish performance standards for existing CWISs for electricity generators using in excess of 50 MGD. The so-called Phase II Rule was published in the Federal Register on July 9, 2004, and became effective on September 7, 2004.

The Phase II Rule calls for a 60 to 90 percent reduction in entrainment and an 80 to 95 percent reduction in impingement mortality from the “calcu lation baseline,” which is essentia lly the entrainment and impingement mortality rates at a similarly sized once-through shor eline CWIS with no impingement and/or entrainment reduction controls at the same location. These ra tes of protection are deemed by USEPA to be “commensurate with closed cycle cooling.” There is no requirement for power plants to adopt closed-cycle cooling. The Rule also provides for site-specific BTA in the event that site specific costs of compliance are “significantly greater” than either th e costs estimated by USEPA for the st ation or for the monetized benefits of compliance at the station.

The Rule allows for five different means of demonstr ating compliance with the requirements of the Rule.

• Compliance Option 1: Flow Reduction. Under Option 1(a) the facility owner can demonstrate that it uses closed-cycle cooling to show compliance with the Rule. Alternativ ely, if the through-screen velocity can be shown to be less than or equal to 0.5 ft/s, the performance goals relative to impingement mortality will be deemed to be met under Option 1(b). This latter approach does not address the potential entrainment performance goals, if applicable.

• Compliance Option 2: Demonstrate that the curr ent system achieves the relevant goals. Through the execution of a CDS, the plant can show that it is currently meeting the performance goals through some combination of technologies as well as operation and restoration measures.

• Compliance Option 3: Demonstrate that a newly installed and operated system (i.e., technology and operation/restoration measures) will meet the goals. Again, through development of a CDS, the plant can design and implement a set of contro ls estimated to achiev e the performance goals.

• Compliance Option 4: Install and operate an approved technology. As part of the Rule, USEPA designated wedge wire screens in a riverine en vironment as an approved technology. Proper installation and operation of this technology wi ll meet the goals of the Rule. NPDES Permit Directors have the ability to designat e other technologies as “Approved.”

• Compliance Option 5: Site-Specific BTA. Under this option, the facility can show that the actual costs of compliance are “significantly greate r” than either the costs or benefits assumed by USEPA. Under this option, the plant is still required to purs ue “cost-effective measures.”

These various options are each associated with differing requirements relative to the CDS. Under Option 1(a), no CDS is required for assessment of impingement mortality, while, under some of the other options, relatively extensive analyses may be required along with submittal of several documents.



### 2.2 CDS Schedule
The Stanton Station’s current NDPDES permit, permi t number ND-0000299, expires on December 31, 2006. Thus, the NDPDES permit renewal appl ication was filed on or before June 30, 2006. Given that GRE’s ongoing Impingement Monitoring Study will not be concluded until July 2006, it was not possible to complete the CDS so that it could be submitted by June 30, 2006. T he rule allows for request of a compliance schedule that partly decouples the NDPDES permit application and the CDS. GRE requested a compliance schedule that allowed delay in the submission of the CDS to as late as January 7, 2008.December 2006 2-4 Document No.: 10735-002-400 

### 2.3 Specific Goals of this PIC
The Stanton Station is affected by the impingement mort ality performance goals of the Phase II Rule. The goal of this PIC is to provide the information necessary to demonstrate that it meets the requirements of the rule.



### 2.4 Review of Document Organization
Data on the physical configuration, flow, and water qua lity of the Missouri River are presented in Chapter 3.0. Discussion of existing and potential additional technologies and measures to mitigate impingement mortality are presented in Chapter 4.0. The nature of histor ical studies and the resulti ng data are summarized in Chapter 5.0. The potential utility of these data to support the CDS also is discussed. Chapter 6.0 presents a review of relevant agency consultations. GRE’s propos ed compliance approach is summarized in Chapter 7.0. Chapter 8.0 discusses the approved sampling work plan.

The PIC document also is supported by appendices that:

1. Provide a general review of impingement mortality mitigation measures ( Appendix A );
2. Present USEPA’s estimated cost of compli ance as summarized in the Phase II rule ( Appendix B );
3. Provide a copy of the Sampling Plan for the on- going monitoring program that is taking place at Stanton as well as two other neighboring power plants ( Appendix C );
4. Provides a bibliography of sources used for a review of the fisheries of the Missouri River including the station-specific data ( Appendix D ); and
5. Provide copies of relevant written agency consultations ( Appendix E ).December 2006 3-1 Document No.: 10735-002-400 

## 3.0 SOURCE WATER BODY INFORMATION

This PIC provides NDDH with information regarding the circumstances that affect operation and performance of the current Stanton Station CWISs, the potential additional measures to reduce impingement mortality, and the compliance approach that GRE proposes to pursue. Al l three of these issues can be affected by the source water body flow rate as well as the physical conf iguration of the source water. GRE believes it may be very productive to consider these iss ues as part of the PIC; the rule anticipates their discussion either as a separate part of the CDS (i.e., the Source Water Bo dy Flow Information – 40 CFR 125.95(b)(2)) or the NDPDES application itself (i.e., the Source Water Body Physical Data Report - 40 CFR 122.21(r)(2)). In order to facilitate NDDH evaluation of this data, GRE has slightly expanded the scope of the PIC to include the discussion here.

The Phase II rule requires, as part of the NDPDES permit application submission, the following information to support Phase II compliance:

1. A narrative description and scaled drawings showing the physical configuration of all source water bodies used by your facility, including aerial dimens ions, depths, salinity and temperature regimes, and other documentation that supports your determinat ion of the waterbody type where each CWIS is located;

2. Identification and characterizati on of the source water body’s hydrological and geomorphological features, as well as methods you used to conduct any physical studies to determine your intake’s area of influence within the waterbody and the results of such studies; and

3. Locational maps.



### 3.1 Source Water Body Physical Description and Flow Information
The Phase II rule requires consideration of Source Wa ter Body Flow Information (40 CFR 125(b)(2)) under two circumstances:

1. The CWIS is on a river or stream and the proportion of river flow taken in by the CWIS is an important potential threshold for the performance goals; and

2. The CWIS is on a lake or reservoir and a propos ed expansion of the CWIS flow might adversely impact the stratification of the water body.

Historically, the Missouri River was a wide, meander ing system, with abundant shallow channel borders, side channels, and back waters. Shifting sand bars and abu ndant debris provided ample habitat for numerous warm-water fishes and invertebrates, but also made navigation difficult or impossible in some areas. Channelization, particularly in the lower Missouri, has allowed commercial naviga tion but has eliminated sandbars and continuity with side channels and backwaters. In the upper Missouri, reservoir construction has created a series of deep-water habitats connected by inter-re servoir reaches that are si gnificantly different in structure and ecology than the pr e-impoundment system. The Garrison Dam was closed in April of 1953, forming Lake Sakakawea, which is the largest of the Mi ssouri River mainstem reservoirs. At maximum surface elevation of 1,855 feet (above mean sea level), Lak e Sakakawea has a storage capacity of approximately 24.7 million acres feet and covers 385,615 (surface) ac res. The section of the Missouri River located downstream of Lake Sakakawea and upstream of Lake Oahe is known as the Garrison Reach.December 2006 3-2 Document No.: 10735-002-400 The Stanton intakes are located on the Garrison R each of the Missouri Rive r, approximately 15 miles downstream of the Garrison Dam. The location of th e Stanton Station relative to the Garrison Dam is presented on Figure 1 . A close-up view of the GRE CWIS location and the CWISs of other nearby power plants is provided on Figure 2 . Flow in this stretch of the river is totally regulated and will vary dependent on release rates from the dam. The closure of Garrison Dam, the fifth largest earthen dam in the U.S., triggered a shift in the nature of the Missouri River downst ream of the dam. The average annual summer surface temperature in Lake Sakakawea is 19oC (66oF), which is colder than all other Missouri River mainstem reservoirs. The dam intake is located approximately 160 fe et below the lake’s surface (at full pool). The water entering the Missouri River is therefore much colder t han historic conditions, and remains cold even during the hottest summer months. Maximum water temperatures in the channel usually do not exceed 20oC (68oF) at Bismarck (70 miles downstream of Garrison Dam).

The formation of Lake Sakakawea also resulted in a ch ange in the sediment transpor t of the Missouri River. Historically a very silt-laden syst em, much of the bed load of fine material is now deposited in the upper reaches of Lake Sakakawea. Since the dam’s closur e, approximately 37 percent of the reservoir’s gross storage capacity has been lost to sedimentation. Sedimentation has decreased below Garrison Dam and water clarity has increased.

The main tributaries of the Garrison Reach of the Mis souri River are the Knife and Heart Rivers and Painted Woods and Square Butte Creek. The Knife River joins the Missouri River from the we st, only a short distance upstream of the Stanton Station. Local run-off into the Missouri River is sparse and seasonal so that the vast majority of flow through the Garrison Reach is due to release from the dam. Flow in the Garrison Reach has averaged 22,490 cfs from 1927 through 2001, as measured at the Bismarck USGS gauging station. Since construction of the dam, annual average flow has rema ined somewhat near this historical mean, though average monthly flows can vary widely due to releas e rates from the dam which vary dependent on hydropower considerations and attempts to balanc e or unbalance Lakes Sakakawea and Oahe, the next downstream reservoir.Riverdale

Underwood

Stanton Pick City Coleharbor



# SITE LOCATION MAP Figure 1 Great Rivers Energy Stanton Station Proposal for Information Collection

USGS 15M Satellite Photo 01-01-2000 McLean, Mercer, and Oliver Counties Garrison Dam

Garrison Dam Tailrace NDG&F Sampling Location
Missouri River

Knife River Confluence Stanton Station NDG&F Sampling Location 

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L e l a n d O l d s S t a t i o n ( B a s i n E l e c t r i c ) C W I S N D G & F S a m p l i n g A r e aDecember 2006 4-1 Document No.: 10735-002-400 

## 4.0 TECHNOLOGIES, OPERATIONAL, AND RESTORATION MEASURES

This section will review current and potential future technologies, operational, and restoration measures relative to their potential to meet the performance goal s of the rule for Stanton Station cost-effectively.



### 4.1 In-place Technologies, Operational Measures

This section describes the current CWIS as well as its apparent performance relative to the performance goals of the Rule.

A concise summary of the Stanton Station, its CWIS, and the available data is provided in Table 1 . The details described in this table are presented in more detail below.



### 4.1.1 Review of Existing Technologies and Operational Measures
The Stanton facility has one generating unit rated at 188 MW. This base loaded unit had an average annual net generation of 1,241,062 MWh from 1998-2003, which amounts to approximately an 80 percent capacity factor. Circulating water for the unit is wi thdrawn through a shoreline intake structure.

The intake structure consists of a small forebay with tras h racks and traveling water screens. The forebay is about 53 feet long and 35 feet wide with an invert at El evation 1,642.0 feet. An old deicing line is located along the walls of the forebay. This line is no longer in service, because spray headers at the inlet to the forebay now provide deicing water. A ve rtical divider wall that sp lits the forebay in half is located about 63 feet downstream from the forebay entrance. Trash racks are located 10 feet. downstream from th is split on each side of the wall. The trash racks are 0.25-inch by 4-inch steel bars at 3-inch center-to-center spacing providing a 2.5-inch clear spacing. The trash racks are sloped at approximately 5.5V:1H. A monorail-mounted trash rake is used to clean the trash racks. A curtain wall with the bottom at Elevation 1,695. 0 feet, which is 1.5 feet below the normal low water level, is located downstream of the trash racks. The curtain wall opening is 19 feet high.

Two traveling water screens are located about 6 feet do wnstream of the curtain wall. The two screens are 10 feet wide and have 0.25-inch square mesh. The screens are rotated twice a day for 45 minutes and cleaned by a high-pressure spray wash. Fish and debris removed from the screens are washed into a trough on the front side of the screens. Once in the trough, fish and debris flow out of the screen house and down a riprap drainage ditch back into the river.

Two vertical, mixed-flow circulating water pumps are loca ted downstream of the traveling screens at the end of two intake tunnels, one tunnel downstream of each screen and one pump in each tunnel. These tunnels are 11.7 feet wide, 19.5 feet high and about 80 feet long. Each pump can provide a total flow of 122.5 cfs (55,000 gpm); combined pump flow is 222.8 cfs (100,0 00 gpm) to the condenser. There also are two auxiliary circulating water pumps located just upstream of the ma in circulating water pumps. Each of these pumps provides a flow of 17.4 cfs (7,500 gpm). During norma l plant operations, both main circulating water pumps and one auxiliary pump are operated, resulting in a flow of 240.3 cfs (107,800 gpm or 155 MGD). When all pumps are operating, the flow to the facili ty is 257.6 cfs (115,600 gpm or 166 MGD).

Warmed cooling water is discharged about 50 feet downri ver of the intake through an open pipe. Discharge water is not typically recirculat ed because the flow of the river ca rries the heated water downstream.December 2006 4-2 Document No.: 10735-002-400 Table 1 Summary of the Circumstances at Stanton Station

Setting Missouri River Capacity Factor N/A, Intake volume is < 5% of normal river flow
Performance Goals Impingement Mortality only Summary of CWIS One shoreline intake located on the bank of the Missouri River. One unit produces appx. 188 MW. Water is drawn from the river water surface. 10 feet long, by 17.5 feet wide forebays are at the end of a 53-foot channel with 0.25-inch traveling screens in place; approach velocity in channel app. 0.7 fps; through-screen velocity app. 1.4 fps. High pressure screen wash to trash collection basket and flow return to river over ground
surface down riverbank.
Number of Units 1 Relationship to Baseline Condition Traveling screens are at the end of a 63-foot channel. Availability of Historical Data No recent site-specific IM data (On-going IM Characterization Study to be completed in June 2006); river fisheries studies; North Da kota Department of Game & Fish (NDG&F)
fish collections since 1991. Applicability of Historic Data Significant amount of recent and historic data collected by NDG&F nearby identifies the species and numbers of fish expected in the area of the CWIS. USEPA Compliance Cost and Technology Estimates Installation of cylindrical wedgewire screens near shoreline for a total capital cost of $0.99 million and annualized cost of $298K/yr (adjusted cost for impingement only is $0.463 million).December 2006 4-3 Document No.: 10735-002-400 Figure 3 Photographs of Cooling Water Intake Structure

Missouri River at Cooling Water Intake

Intake Structure ChannelDecember 2006 4-4 Document No.: 10735-002-400 Opening to Screen House

Traveling Screen Spray Wash Sample Collection BasketDecember 2006 4-5 Document No.: 10735-002-400 

### 4.1.2 Restoration Measures
No restoration measures have been performed.



### 4.1.3 Performance Estimates
Estimates of performance relative to the rule’s goals are contained in Table 2 . The following paragraphs provide discussion of data used to estimate the per formance based on the CWIS’s differences from the Calculation Baseline.

Table 2 Estimated CWIS Performance Goal: 80 to 95 Percent Reduction in Impingement Mortality (IM)

Estimated Reduction in IM IM - Difference from Baseline (%) Basis Notes 1/4-inch mesh traveling screens 10 Engineering judgment High pressure wash and debris return, but not designed as fish return system Intake structure is at the end of a 65-foot canal as opposed to flush against the river bank 10 Engineering judgment With canal, fish have an opportunity to escape before the traveling screens

Total IM Reduction 19 Not meeting goal



### 4.2 Potential Technologies, Operationa l Measures, and Restoration Measures
A summary of general technologies and operational meas ures available to address impingement mortality are presented in Table 3 . This table presents the technology, estimated effectiveness in addressing impingement mortality, estimated technology cost, and notes on wh y or why not the technology was retained for further feasibility analysis. Appendix A provides a more in-dep th general analysis of each technology and operational measure considered in Table 3 . A listing of those technologies that were considered most promising for the Stanton Station is provided in Section 4.2.1.



### 4.2.1 Review of Technologies
The following criteria are used to assess the technologies and operational measures presented in Table 3 :

• Technical feasibility and reliability;

• Effectiveness in meeting the Rule’s performance goals;

• Costs relative to USEPA estimate developed as part of the Rule-making; and

• Potential for other adverse effects.December 2006 4-6 Document No.: 10735-002-400

Table 3 Primary Assessment of Mitigation Measures

Construction and Operation Issues 2

BTA Alternative Cost (Capital plus O&M) 1 Power Plant Efficiency Impact 2 Station Outage with Construction Navigation Effects Potential Clogging Potential Adverse Environmental Effects 2 IM Benefits/ Effectiveness E Benefits/ Effectiveness Traveling Screen Modifications Modified traveling

screens (dual flow) 3 0 ** 0 0 0 IM reduction if through screen velocity is reduced. None if standard screen mesh is used.

Modified traveling screens (Ristroph Screens) 2 0 ** 0 0 0 Effective IM reduction for many species. May not be effective for sensitive species None, if std. mesh size.

Fine Mesh Screens on traveling screen system. 6 0 ** 0 ** 0 Effective with adequate fish handling system Potential entrainment reduction, but survivability uncertain even with fish handling system.

Angled and modular inclined

screens 3 0 ** 0 0 0 Potential impingement reduction for some

species given effective fish return none

Fixed Screening Devices

Wedgewire

Screens 2.5 0   **  * Effective impingement reduction if through screen velocity is

appropriate. Potential for E reduction may depend on slot size, cross-flow current,

productivity of surrounding area.

Perforated Pipes not estimated 0 * * ** 0 Some benefit possible because of absence of a confined channel in

which fish can become trapped. none

Barrier Net 0.5 0 0 ** * 0 High if properlyinstalled and wintertime impingement is low. None

Aquatic Filter Barrier (e.g., Gunderboom) 8 0 0 ** ** * IM reduction for all species E reduction for all species

Porous Dike / Leaky Dam 4 0 * ** ** * High if through-dike velocities are low and/or behavior

measures to

minimize. Variable depending on size of gaps

New Intake location

Offshore Intake Structure (with

wedgewire

screen) 4 0 ** ** * * Potential reduction for some species,

depending on population density differences Potential reduction for some species,

depending on population density differences Fish Diversion and Avoidance

Diversion Devices: Louvers and Bar Racks 1 0 0 * * 0 Potential impingement reduction for some

species given effective by-pass None

Velocity cap on offshore intake 2 0 ** ** 0 0 Potential reduction for some species,

depending on population density differences Potential reduction for some species,

depending on population density differences Behavioral Barriers: Strobe Lights, acoustic deterrent, bubbles, chains 0.5 0 0 0 0 0 or * Potential impingement reduction for some species NoneDecember 2006 4-7 Document No.: 10735-002-400

Table 3 Primary Assessment of Mitigation Measures

Construction and Operation Issues 2

BTA Alternative Cost (Capital plus O&M) 1 Power Plant Efficiency Impact 2 Station Outage with Construction Navigation Effects Potential Clogging Potential Adverse Environmental Effects 2 IM Benefits/ Effectiveness E Benefits/ Effectiveness Flow Reduction

Variable Speed Pumps 2 * * 0 0 * IM reduction proportional to flow reduction. E reduction proportional to flow

reduction, more effective during spawning period

Capacity Factor

Reduction variable ** 0 0 0 0 IM reduction proportional to flow reduction. E reduction proportional to flow

reduction, more effective during spawning period Evaporative Cooling Towers 42 ** ** 0 0 * IM reduction for all species E reduction for all species
Dry Cooling Tower 60 ** ** 0 0 * IM reduction for all species E reduction for all species Increased Fish Population

Restoration 0.05 to 1 0 0 0 0 0 Requires site-specific analysis Requires site-specific analysis

Notes:

1 Costs do not include: a) thermal effici ency reduction or b) out age for construction.

2 Adverse effects: 0 = Negligible * = Significant ** = Potentially severe

3 IM = Impingement Mortality of Aquatic Organisms

4 E = Entrainment of Aquatic OrganismsDecember 2006 4-8 Document No.: 10735-002-400 Site-specific technologies considered for the Stanton Station included:

• Technology Alternative 1 – Tr aveling Screen Modifications
1a – Dual Flow Screens (Impingement)
1b – Ristroph Screens (Impingement)

1c – Fine Mesh Screens (Impingement and Entrainment)
1d – Angled and modular inclined screens (Impingement)

• Technology Alternative 2 – Fixed Screening Devices
2a – Wedgewire Screens (Impingement and possibly Entrainment)
2b – Perforated Pipes (Impingement)
2c – Barrier Net (Impingement)
2d – Aquatic Filter Barrier (Impingement and Entrainment)
2e – Porous Dike / Leaky Dam (Impingement and Entrainment)

• Technology Alternative 3 – Offshore Intake (Impingement and Entrainment)

• Alternative 4 – Fish Diversion and Avoidance
4a – Louvers and Bar Racks (Impingement)
4b – Velocity Cap (Impingement)
4c – Strobe lights, acoustic deterre nt, bubbles, chains (Impingement)

• Technology Alternative 5 – Flow Reduction
5a – Variable Speed Pumps (Impingement and Entrainment)
5b – Capacity Factor Reduction (Impingement and Entrainment)
5c – Evaporative Cooling Towers (Impingement and Entrainment)
5d – Dry Cooling (Impingement and Entrainment)

• Technology Alternative 6 – Restor ation (Impingement and Entrainment)

In Table 3 , the capital costs for technology installation have been estimated for planning purposes. These costs are approximate but they do account for a number of site specific aspects. Table 3 also provides a qualitative discussion of potential operation and maintenanc e costs. Costs associated with facility downtime during construction also are likely but have not been es timated here due to the uncertainty in construction timing and the need to suspend operations at a given unit. In the execution of the Cost -benefit test, all of these issues will be revisited in a more formal fashion and thei r results expressed consistent with the requirement of the rule.

The cost estimates for the various technologies were prepared by using the following resources:

• USEPA Technical Development Document for the Final Section 316(b) Phase II Existing Facilities Rule, February 12, 2004. (EPA-821-R-04-007).

• USEPA Technical Development Document for th e Proposed Section 316(b) Phase II Existing Facilities Proposed Rule, April 2002. (EPA-821-R-02-003).

• Cost estimates and/or installed costs for similar equi pment obtained by ENSR from vendors and other operating facilities.December 2006 4-9 Document No.: 10735-002-400 Available costs were adjusted to account for size/capacity diff erences as follows:

• Proportionally for components/equipment whose costs were judged to be proportional to size (e.g., pipe length); and

• By the 6/10ths rule for those components whose costs were judged to not be directly proportional to size (e.g., pumps).

The following factors were applied, where appropriate:

• 10 percent Allowance for Indeterminants (AFI), a contingency on costs of the items included.

• 30 percent Contingency, to address unforeseen items, especially with regard to a facility retrofit.

• Escalation based on the time frame of the basis cost estimate. Since the basis cost year varied, estimated costs were escalated based on 3 percent annual rate of inflation.



### 4.2.2 Review of Operational Measures
Two operational measures are considered for the Stanton St ation: more frequent rotation of the traveling water screens in order to reduce impingement mortality and fl ow reduction. These options are discussed fully in Appendix A

.
Evaporative cooling towers and dry cooling are much more costly than USEPA’s estimate for compliance and, therefore, will not be considered fu rther. However, for reference, costs for these options are presented in Table 3

.



### 4.2.3 Review of Restoration Measures
Restoration can be a very cost-effective measure fo r mitigating losses of aquatic organisms. Under some circumstances it may be possible to effect one-to-one r eplacement of important species or otherwise improve the ecosystem by an “out-of-kind” restoration, allowed by the rule. Examples of restoration methods generally include; fish restocking programs, habitat creation, habitat enhancement, and support of a state-sponsored restoration program.

Of the available restoration measures, GRE favors those that have a direct impact on the species of concern (i.e., collaborative stocking programs with NDG&F) rather than habitat restoration which has a more tenuous connection to fisheries populations and is likely to be mo re costly. A more detaile d discussion of restoration options is presented in Appendix A

.
At this time, the status of restoration under the rule is uncertain given pending cour t review. The final program costs as well as its effectiveness also are uncertain. However, given the relatively low expected levels of impingement mortality based on data collected to date through the Impingement Mortality study conducted by GRE, restoration is an attractive mitigation measure that should be retained for further evaluation.



### 4.2.4 Estimate of Technology and Operational Measures Costs and Effectiveness

The estimated costs and effectiveness of the ev aluated technologies and operational measures are summarized in Table 3

.December 2006 4-10 Document No.: 10735-002-400 

### 4.2.5 USEPA’s Appraisal of Technologies
As part of the Rule making process, USEPA developed an estimate of the cost of compliance with the Phase II Rule at each of the affected plants. These data are pr ovided for the Stanton Station, with some slight modification to their presentation, as Appendix B

.
In the final Rule, USEPA does not present facility-specific estimates of the benefit of compliance to area fisheries. Instead, USEPA requires that the benefits of potential technologies and measures be estimated based on likely technology effectiveness and those benefit s expressed as a monetized value using procedures defined in the Rule. The monetized value will be compared to the costs of the potential technology or measure. Under the Rule, if the costs are “significantly greate r” than the estimated benefits, a site-specific BTA can be issued.

USEPA identified the Stanton Station as being a facili ty that had to comply with both impingement and entrainment reduction requirements. USEPA has estimated that fine-m esh wedgewire screens installed near the shoreline and operated in conjunction with existi ng traveling screens would be effective at reducing impingement mortality consistent with the rule’s goals. USEPA also has assumed that entrainment reduction would be necessary and estimated that the screens could be installed at a total capital cost of $994,534 (see Appendix B ). However, USEPA’s guidance states that if a facility determines it must only comply with impingement reduction requirements, the corresponding USEP A estimated cost can be calculated by dividing USEPA’s original cost estimate by 2. 148. Dividing $0.99 million by 2.148 re sults in an USEPA cost estimate for the Stanton Station of $0.463 million. This is the costestimate that should be used for comparison and costcost/cost-benefit analyses.



### 4.3 Selection of Proposed Technologies, Operational and Restoration Measures
Several technologies have the potential to be effectiv e at reducing impingement mortality. These range in complexity and cost from behavioral barriers to inst allation and optimized operation of Ristroph-type buckets on the traveling screens. A total of six alternativ es that included eighteen opt ions have been screened based on their technical feasibility, effectiveness and rela tive costs. This evaluation is included as Appendix A and is summarized on Table 3

.
Based on this screening assessment, the following pot ential technologies or measures are proposed for further evaluation in the CDS:

• Technology Alternative 1 – Tr aveling Screen Modifications

1a – Dual Flow Screens
1b – Ristroph Screens

• Technology Alternative 2 – Fixed Screening Devices
2a – Wedgewire Screens

2c – Barrier Net

• Technology Alternative 4 – Fish Diversion and Avoidance
4c – Strobe lights, acoustic deterrent, bubbles, chains

• Technology Alternative 5 – Flow Reduction
5a – Variable Speed Pumps
5b – Capacity Factor Reduction

• Technology Alternative 6 – RestorationDecember 2006 5-1 Document No.: 10735-002-400 

## 5.0 HISTORICAL STUDY REVIEW

Relevant historic impingement and entrainment studies have not been conducted at Stanton or at other, similar power stations in the area. An impingement mo rtality study was conducted at Stanton and two other nearby power stations and was completed in July 2006. The multi-station impingement mortality study work plan is provided in Appendix C . Several studies of the Missouri River have been completed and are described in the following sections. The ability of th e combined data set to support the requirements of the Phase II rule, in particular the Impingement Mortalit y Characterization Study (IMCS), is discussed in Section 4.2. GRE does not propose to colle ct additional source water body data.



### 5.1 Historical Biological and Physical Data

The Stanton CWIS is located on the Garrison Reach of the Missouri River. This reach has been studied thoroughly with regard to aquatic spec ies for many years by Federal and State agencies as well as other independent researchers. Twenty reports on various aspects of the status of the fishery along the Garrison Reach have been researched during the development of this PIC (a bibliography of these sources is provided in Appendix D ). Most significantly, North Dakota Game and Fish Department has conducted fish population studies in the Garrison Reach since 1991. These studi es involved semi-annual fish collection at seven locations in the Garrison Reach. One of these collection locations is offshore of the Great River Energy (GRE) Stanton Station’s cooling water outfall. The location of the North Dakota Game and Fish Stanton sampling point is identified on Figure 2

.
Figure 4 presents a complete list of all the fish species identified in the Garris on Reach from 1991 through 2003 3

. Figure 5 presents the number of each species identified at the Stanton Station by North Dakota Game and Fish during sampling events in summer and in fall from 1997 through 2004. The second condition listed above will be addressed by the data collected by North Da kota Game and Fish since it is likely that fish populations and movement were at their highest levels in the months that were sampled. The impingement characterization study will provide additional species occurrence data for the entire year. The existing data have been used to identify the species of fish likely to be found during th e impingement characterization study and will be utilized to analyze the potential impact of impingement in the study report and during completion of the CDS. Additional data collected by North Dakota Game and Fish and other organizations will be incorporated into the study as soon as they are made available.

3 North Dakota Fisheries Investigations, Aquatic Investigations of the Missouri Mainstream in North Dakota, by Jeff Hendrickson, North

Dakota Game and Fish Department, March 2004.December 2006 5-3 Document No.: 10735-002-400 Figure 5 Summary of Fish Collected by NDG&F at Stanton Station 1997-2004 Total Number of Each Fish Specie Present at Stanton Sampling Site NDG&F Sampling 1997 – 2004 Summer Fall Bigmouth Buffalo 15 160
Black Bullhead 0 0 Black Crappie 0 0 Bluegill 0 0
Blue Sucker 15 8
Brown Trout 2 25
Brook Stickleback 0 0
Burbot 1 6 Common Carp 84 125
Channel Catfish 11 7
Cisco 0 7
Common Shiner 9 0
Cutthroat Trout 16 5
Emerald Shiner 39 142
Chinook Salmon 15 7
Fathead Minnow 0 1
Freshwater Drum 5 5 Goldeye 11 8
Golden Shiner 0 0 Johnny Darter 4 39 Largemouth Bass 0 0 Longnose Dace 0 1 Longnose Sucker 100 103
Northern Pike 25 8 Orange Spotted Sunfish 0 0
Paddlefish 3 0
Rainbow Smelt 3 14
Rainbow Trout 1 4 River Carpsucker 330 295
Smallmouth Buffalo 8 43 Sauger 38 34
Shorthead Redhorse 140 65
Smallmouth Bass 9 7
Shortnose Gar 3 7 Shovelnose Sturgeon 4 7 Spottail Shiner 0 3 Walleye 264 203
White Bass 50 38 White Sucker 389 409 Western Silvery Minnow 0 1
Yellow Perch 0 3 Totals 1,594 1,790December 2006 5-4 Document No.: 10735-002-400 The data collected by North Dakota Game and Fish as well as other researchers provide a relevant and ongoing characterization of the biological conditions and populations in the river near the intake structure of the Stanton power plant. The data are representative of current conditions and were collected using appropriate QA/QC procedures by agencies of the State of Nort h Dakota. The Impingement Characterization Study as described in this PIC will comply with the third condition listed above and will complete the data set required by the rule. The IM study work plan is included in Appendix C

.
In 1974 and 1978, studies were conducted by Dr. Joe Neel with the University of North Dakota at the request of Basin Electric. The studies were intended to determi ne the temperature, chemical and biological effects of the water withdrawal and discharge from the Leland Olds Station just downstream of the Stanton Station. The 1978 study, “Life in the Missouri River with War ming by 676 Megawatts Gross Steam Generated Power Production”, conducted fish sampling at the intakes, at the screens and wash water return and downstream of the discharge. Observations and sampling were mainly conducted in the late spring and summer months. Fifteen species of fish were observed or captured and the text of the report states that primarily bullhead fingerlings were found in the intakes and on the intake screens. The data presented in the report indicated that during fifteen days of sampling the traveling screens, 56 fish were recovered from intake screen washings and 44 of these fish were black bullheads. River temperatures we re slightly elevated in the vicinity of the discharge but the report states that they were not as high as temper atures found naturally in other stretches of the river. The report states that “the intake does not appear to pose a great threat to adult fish , but is more hazardous to young, particularly to schooling bullheads.”

A review of a recent publication, “Distr ibution and habitat use of sturgeon chubs ( Macrhybopsis gelida ) and sicklefin chubs ( M. meeki ) in the Missouri and Yellowstone Rivers, North Dakota” (Everett, Scarnecchia and Ryckman, 2004) indicated that, in recent sampling studies of the Missouri River in the vicinity of the station, there were no chubs of either spec ies collected. The authors of the study concluded that this was probably due to significantly deeper, faster and clearer water than was found in the other river segments studied.



### 5.2 Assessment of Data Sufficiency
Among the requirements of the CDS is the performance of a study of impingement mortality. The results of this study may be used to assess the performance of the cu rrent CWIS as well as evaluate additional potential technologies and measures. The Rule se ts out specific requirements for this study and addressing these goals is an important aspect of the PIC. The Rule anticipates t hat it may be possible to base the CDS completely or in part on existing data. For these reasons, Table 4 presents the specific data requirements for the study and reviews the relevance of available data to these r equirements. The table also comments on the potential necessity of additional field data.December 2006 5-5 Document No.: 10735-002-400

Table 4 Assessment of Data Sufficiency

Rule Citation Requirement Historical Data Source Notes Additional Data Proposed? 125.95(b)(3)(i) Taxonomic identifications of all life stages of fish, shellfish, and any species protected under Federal, State, or Tribal Law (including threatened or endangered species) that are in the vicinity of the cooling water intake structure(s) and are susceptible to impingement and entrainment. SiteSpecific; Regional Literature Surveys of extant populations and reference materials can be used to assess historical trends and current populations in the

area. No

125.95(b)(3)(ii) A characterization of all life stages of fish, shellfish, and any species protected under Federal, State, or Tribal Law (including threatened or endangered species) identified pursuant to paragraph (b)(3)(i) of this section, including a description of the abundance and temporal and spatial characteristics in the vicinity of the cooling water intake structure(s), based on sufficient data to characterize annual, seasonal, and diel variations in impingement mortality and entrainment. SiteSpecific; Regional Literature Surveys of extant populations and reference materials can be used to assess historical trends and current populations in the

area. No

125.95(b)(3)(iii) Documentation of the current impingement mortality and entrainment of all life stages of fish, shellfish, and any species protected under Federal, State, or Tribal Law (including threatened or endangered species) identified pursuant to paragraph (b)(3)(i) of this section and an estimate of impingement mortality and entrainment to be used as the calculation baseline. Impingement mortality and entrainment samples to support the calculations required in Section 125.95(b)(4)(i)(C) and 125.95(b)(5)(iii) of the Rule must be collected during periods of representative operational flows for the cooling water intake structure and the flows associated with the samples must be documented. None Historic rates of impingement mortality have not been quantified. Yes – Current year-long IMCharacterization Study will conclude in June 2006. Results will be incorporated in CDS documents.

In summary, GRE believes that the weal th of data available on the Missour i River and its environs will support the goals of the Rule in general and the IMECS in particular.December 2006 6-1 Document No.: 10735-002-400 

## 6.0 AGENCY CONSULTATIONS

The Rule requirements for the PIC ask for a summary of any past or ongoing consultations with appropriate federal, state, and Tribal fish and wild life agencies that are relevant to this Study and a copy of written comments received as a result of such consultations. GRE believes that the goal of this summary is to provide NDDH with full perspective on the historical permitting of the CWIS as well as any potential concern by relevant fisheries management or other natural re sources agencies. Copies of correspondence with the agencies are presented in Appendix E

.


### 6.1 Section 316(b)-Specific Consultations
A draft of the Impingement Mortality Sampling Plan was submitted to NDDH and the NDG&F in May 2005 and discussed in a meeting later that month. Comments were received and incorporated into the Plan. An approval from NDDH was received in August 2005 and is provided in Appendix E

.
The Impingement Mortality Study was completed in July 2006. A meeting was held with NDDH, NDG&F and U.S. Fish and Wildlife Service (USF WS) representatives in October 2006 to review the study data and discuss its implications for 316(b) compliance.



### 6.2 Other Relevant Consultations

GRE has communicated on several occasions with NDG&F relative to impingement of fisheries at Stanton Station and the status of the Missouri River fishery in the general area of the Stanton Station. GRE also has consulted with the USFWS with regard to Threatened or Endangered species in the vicinity of the Stanton Station CWIS. These consultations were taken into ac count in the formulation of the Impingement Mortality Sampling Plan that is described in Section 6 and presented in Appendix C

.December 2006 7-1 Document No.: 10735-002-400 

## 7.0 PROPOSED COMPLIANCE APPROACH

GRE’s proposed approach to Phase II Rule compli ance is a BTA determination based on Compliance Option 5 – actual costs of compliance are “significantly greater” than the benefit to be gained from installation of any of the appropriate technologies.



### 7.1 Outline of CDS Activities
According to 40 CFR Section 125.95(b), the “Compreh ensive Demonstration Study is to characterize impingement mortality and entrainment, to describe the operation of your cooling water intake structures, and to confirm that the technologies, operational measur es, and/or restoration measures you have selected and installed, or will install, at your facility meet the applicable requirements of §125.94.” As outlined in Section 125.95(b), a CDS intended to support Compliance Option 5 based on the Cost/Benefit test must include:

• Proposal for Information Collection (PIC)

• Source Waterbody Flow Information

• Impingement Mortality and/or Entrainment Characterization Study (as appropriate)

• Technology Installation and Operation Plan (TIOP) (if appropriate)

• Restoration Plan (if appropriate)

• Information to support site-specific determination of best technology available for minimizing adverse environmental impact

o Comprehensive Cost Evaluation Study

o Valuation of Monetized Benefits of Reducing IM&E

o Site-Specific Technology Plan

• Verification Monitoring Plan

GRE will prepare each of these document s and submit them to NDDH for review.



### 7.2 Review of CDS Approach
The CDS approach for the Stanton Station includes provid ing the required information and submittals so that:

• Rates of impingement mortality will be quantified for 1 year.

• The Impingement Mortality Characterization Study w ill summarize the full range of available data in order to estimate the extent of mitigation from the Calculation Baseline as well as estimate the current losses.

• Existing technologies and oper ational measures to achieve the impingement mortality goal will be described and their effectiveness estimated based on currently available data. The assessment will consider the feasibility and reliabi lity of the technology as well as its likely effectiveness and cost.

• Alternative technologies or measures to cont rol impingement mortality will be evaluated for effectiveness, feasibility, and costs. GRE believes th at each alternative technology and measure will be shown to be significantly more costly than the USEPA estimate of compliance costs at the Stanton Station. For this reason, the site-s pecific BTA (i.e., Compliance Option 5) will be purs ued on the basis of the Cost/Benefit test.December 2006 7-2 Document No.: 10735-002-400 • The technology assessment and discussion of the inst allation and operation of selected measures will be presented in the Site-Specific Technology Pl an, and/or the Restoration Plan, as appropriate.

• The nature of the proposed ongoing compliance activities including their timing will be outlined in the Technology Installation and Operation Plan.



### 7.3 Schedule
The following is a conservative schedule for the Stanton CDS: A compliance schedule will be requested to postpone submittal beyond NDPDES permit renew al, as allowed by the regulations.

• Submit NDPDES permit renewal application and r equest 316(b) compliance extension to NDDH by June 30, 2006;

• Develop Impingement Mortality Characteriza tion Study Report by September 30, 2006;

• Submit PIC to NDDH by December 15, 2006;

• Receive approval of PIC from NDDH by January 31, 2007;

• Submit the Technology Installation and Operation Pl an (TIOP) and Restoration Plan (if appropriate) by June 30, 2007;

• Submit information to support the site-speci fic best technology available (BTA), including the Comprehensive Cost Evaluation Study (CCES), Valuat ion of Monetized Benefi ts of reducing IM, and the Site-Specific Technology Pl an (SSTP) by July 31, 2007;

• Meet with NDDH to discuss submittals and proposed BTA by September 1, 2007;

• Submit the Verification Monitori ng Plan to NDDH by September 30, 2007;

• Approval of Verification Monitori ng Plan by NDDH by October 31, 2007;

• Implement Verification Monitoring Plan by November 30, 2007;

• Receive modified NDPDES permit from NDDH by December 31, 2007.

GRE notes that this schedule is an approximation but ex pects to achieve full co mpliance well before the maximum allowed extension deadline of June 2009.December 2006 8-1 Document No.: 10735-002-400 

## 8.0 SAMPLING PLAN

The Sampling Plan that was implemented at t he Stanton Station in June 2005 is included as Appendix C to this PIC. It was submitted to NDDH as a separate doc ument in May 2005 for preliminary approval. Approval was provided by NDDH in August 2005. A copy of the approval letter is provided in Appendix E . The sampling program was competed in July 2006.December 2006 Document No.: 10735-002-400 

## Appendix A

Technology ReviewDecember 2006 Document No.: 10735-002-400 General Technology Overview

This section provides a general review of a compr ehensive list of potential mitigation methods to reduce impingement mortality and entrainment. The nature of the technology is briefly reviewed and its approximate costs 4 are presented. The effectiveness un der the conditions at the Stant on Station is discussed and factors affecting performance, reliability, and other environmental issues are reviewed. In addition to CWIS technologies, facility operation and rest oration measures are considered.

The following list of CWIS alternatives have been evaluated in this screening assessment:

• Technology Alternative 1 – Tr aveling Screen Modifications
1a – Dual Flow Screens (Impingement)
1b – Ristroph Screens (Impingement)

1c – Fine Mesh Screens (Impingement and Entrainment)
1d – Angled and modular inclined screens (Impingement)

• Technology Alternative 2 – Fixed Screening Devices
2a – Wedgewire Screens (Impingement and possibly entrainment)
2b – Perforated Pipes (Impingement)
2c – Barrier Net (Impingement)
2d – Aquatic Filter Barrier (Impingement and Entrainment)
2e – Porous Dike/Leaky Dam (Impingement and Entrainment)

• Technology Alternative 3 – Offshore Intake (Impingement and Entrainment)

• Technology Alternative 4 – Fish Diversion and Avoidance
4a – Louvers and Bar Racks (Impingement)
4b – Velocity Cap (Impingement)
4c – Strobe lights, acoustic deterre nt, bubbles, chains (Impingement)

• Technology Alternative 5 – Flow Reduction
5a – Variable Speed Pumps (Impingement and Entrainment)
5b – Capacity Factor Reduction (Impingement and Entrainment)
5c – Evaporative Cooling Towers (Impingement and Entrainment)
5d - Dry Cooling (Impingement and Entrainment)

• Technology Alternative 6 – Restor ation (Impingement and Entrainment)

4 This report presents estimates of the capital costs of potential mitigation measures as a means of illustrating their potentia l costeffectiveness. The estimates should be considered approximate and final costs may vary by as much as factor of two or more. Cos t estimates for mitigation measures do not acco unt for facility down-time asso ciated with construction or operation/ maintenance. These costs will be estimated with input from GRE and included in the final CDS document especially in the info rmation to support the Sitespecific BTA. Costs will be annualized according the procedures defined in the rule.December 2006 Document No.: 10735-002-400 Technology Alternative 1 – Traveling Screen Modifications with Fish Removal and Return System

• 1a – Dual Flow Screens

Description:

With dual-flow, single-exit screen, incoming water is filtered with both the upwar d and downward moving parts of the screen, and the water flows toward the pump from the interior through the open side of the screen. The screen faces are oriented parallel to the direction of flow. If space is available, the screen length can be extended outward such that the area of the screens c an be greater than the area of a conventional flowthrough screen in the same location. Therefore, the dual-flow design has the potential to reduce throughscreen velocity compared to flow-throug h (single entry, single exit) design.

The dual-flow design also provides an advantage of elim inating the potential for debris that is stuck on the screen to be dislodged in the downstream side of the scr een. This feature has an added benefit of lower wash water pressure requirements.

Technical Feasibility and Reliability:

For retrofit applications, the space available to inst all may be limited by the existing structure (trash racks upstream and pump vault downstream) and water body constr aints (navigation). Such limitations may limit the ability to increase screen surface area, thereby limiti ng the ability to reduce through-screen velocity.

Hydraulic issues with a dual-flow screen are commonly encountered. One of the comm on limitations with dualflow screens is the flow disruption that is caused by the two 90-degree turns that cooling water must undergo to pass through the system. These issues can be minimiz ed (but not eliminated) by proper hydraulic analysis and design.

Dual flow screen are commercially ava ilable and have been in use for years.

For the site-specific evaluations, the dual-flow screens with conventional mesh are assumed to provide adequate screen area to reduce through-screen velocity to 0. 5 feet per second (ft/s). Otherwise, there would be no advantage to changing from a through-flow screen to a dual-flow screen. In some cases, the required screen area may result in the need for additional new intake structures to accommodate the screens.

Cost Considerations:

The cost of dual-flow screens is expected to be up to 20 percent higher than comparable through-flow

screens.

Effectiveness:

Dual flow screens have the potential to reduce through-scr een velocities and therefore impingement mortality, with the addition of an appropriate fish handling and re turn system. However, depending on the proximity of other screens and structures, the full screen area may not be effectively used, and through screen velocities on parts of the screen may be substantially higher than design, thereby reducing the potential to reduce impingement. In fact, if dual-flow screens are placed in re latively narrow intake bays, the approach velocity to the screen will likely increase and the impingement rate c ould increase. In general, s pace constraints may limit effective application of this technology.

Potential for Other Adverse Effects:December 2006 Document No.: 10735-002-400 An intake structure that is reconstructed to a ccommodate a larger dual-flow screen may interfere with navigation.

Overall Assessment of Alternative:

Installation of dual-flow screens could result in a reducti on of impingement mortality. However, in order to reduce through-screen velocity to 0.5 fps, installation of dual-screens would require significant expansion of the existing intake structure. The potential cost of this expansion and installation would need to be compared to the benefit to be gained from the improvement based on the results of the on-going IM study. This technology is recommended for further study.

• 1b – Ristroph Screens

Description:

This alternative would invo lve modification of the traveling screens so that fish which are impinged on the screens could be removed and returned to the source water body with minimal stress and mortality.

A range of measures could be pursued to optimize fish handling and return. This might include more frequent rotation of the screens, re-fitting the screen with fish bucke ts, institution of low-pre ssure wash, replacement of the fish return trough, and rerouting of the fish return to a more suitable location. A complete refurbishment might consist of the following measur es: A low-pressure spray would be used for fish removal prior to the high- pressure debris removal spray wash. Fish would be carri ed in fish buckets (i.e., water-filled lifting buckets designed such that they will hold approximately 2 inches of water once they have cleared the surface of the water during the normal rotation of the traveling screens). The fish bucket would be designed to hold the fish in water until the screen reaches the point where the fish are washed by the low pressure spray onto a sluiceway. The modified traveling screens would be op erated continuously during periods when fish are being impinged. Removed fish would be returned to the source water body by a sluiceway with a smooth surface and sides that retain water such that organisms are gently returned to a location removed at least 100 feet from the intake structure such that the potential for re -impingement would be minimized. All surfaces of the fish handling and return system would be smooth to minimize abrasion damage to organisms.

Technical Feasibility and Reliability:

The technology proposed for this alternative is well known and has been implemented for numerous power plants. However, a separate collection and piping syst em may need to be constructed to provide a separate return path for fish to the river or lake. This piping system would have to be cons tructed within the existing power plant footprint which could present engineering, construction, and logistics problems. Routine maintenance, primarily consisting of inspection and cle aning of the fish handing and return system, would be required but not expected to be extensive. Maintaining the system during icing conditions is likely to be complicated. The modified fish troughs extend fart her out from the screens than conventional troughs. Therefore, space limitations may affect t he cost and feasibility of installation.

Cost Considerations:

The retrofit of a fish removal and return system should consider complete replacement of the existing traveling screens. Installation of an effective fish return system can be complex and expensive. Operation and maintenance activities include frequent, if not c ontinuous, screen operation and power costs for screen and water spray operation.December 2006 Document No.: 10735-002-400 Effectiveness:

Modified screens and fish handling and return systems hav e been used to minimize impingement mortality at a wide number of facilities throughout th e United States (U.S.). Studies have demonstrated survival of impinged fish over a wide range. Survival rates of 70 to 80 percent are typically achiev ed for some species. It is notable that many small schooling species (e.g., anchovies) suffe r from high mortality at traveling screens even those with Ristroph-type modifications.

Potential for Other Adverse Effects:

No adverse effects are expect ed from this alternative.

Overall Assessment of Alternative:

Modification to traveling screens would likely result in a reduction of impingement mortality. However, installation of Ristroph Screens would require signifi cant expansion of the existing intake structure at considerable cost. Because this modification has the pot ential to reduce IM, it merits further study during the CDS process.

• 1c – Fine Mesh Traveling Screens

Description:

Typical vertical traveling screens, with mesh sizes r anging from 1/8-inch to 3⁄4-inch, are not designed to screen ichthyoplankton or eggs from the intake water. This alternative would involve replacement of the existing traveling screens with fine mesh screens having mesh spac ing as small as one millimeter. This mesh spacing would result in a reduction of entrainment of fish eggs and larvae. In addition, an intake approach velocity of 0.5 ft/s or less would be necessary to minimize ph ysical damage to plankton that would be impinged on the fine mesh screens.

Because of flow area for a screen with one-mm (about 1/32-inch) mesh is appr oximately two thirds that of a 3/8-inch mesh, the screen area would have to be incr eased by nearly 50 percent to maintain the same through-screen velocity. For most stations, the screen area would have to be further increased to maintain a 0.5 ft/s velocity to reduce mortality of impinged fish or shellfish. In most cases, the area around the existing pump house/screen house structure is not sufficient to allow for the increased number of fine mesh screens without substantial modification to the facilities. The screens would be operated continuously to prevent excessive accumulation of debris and organisms.

The fine mesh screen structure would include curtain wa lls to protect against floating debris, bar racks to prevent submerged debris from damaging the fine mesh screens, and a screen wash and marine biota removal and open sluice biota return system (similar to that described for the Ristroph screen).

Technical Feasibility/Reliability:

The technology and construction tec hniques required for this option hav e been used at a limited number of power plants, often with limited reli ability. At two power stations, Mill stone and Brayton Point, the fine mesh screens were replaced with standard screen mesh a fter clogging incidents. Based on the available information, it is concluded that ther e is a relatively high potential for fouling of the intake screens and that extensive maintenance would likely be required.

In conclusion, because of the potentially large increas e in screen area required, site -specific conditions may preclude the installation of a modified intake structure of sufficient size.December 2006 Document No.: 10735-002-400 Cost Considerations:

The capital cost of the fine mesh screen alternative shoul d include any necessary modifications to the intake structure, as well as construction of an effective fish re turn system to handle the more sensitive species or life stages of fish and shellfish. Operation and maintenanc e costs include one maintenance episode (6 days) each year, replacement parts, system mo nitoring by station staff (10 hours per week), and power costs.

Effectiveness:

Fine mesh screens, with a low pressure wash and return system, have not been demonstrated to result in consistent effectiveness in reducing mortality at early life stages. This is a si gnificant concern because organisms that are entrained and discharged may have a far greater chance of survival than if such organisms are impinged and subsequently washed back to the receiv ing water. Therefore, even though entrainment reductions of 50 percent to over 90 percent have been achieved at number of power stations using fine mesh screens, compliance with the impingem ent mortality performance standard could be in jeopardy. Because the calculation baseline levels of entrained organisms ar e typically far greater than the levels of impinged organisms, the reduction in impingement mortality will likely need to be near ly 100 percent for the early life stages to meet the 80 to 95 percent performance standard.

Potential for Other Adverse Effects:

The major potential adverse effect associated with the te chnology is the potential unreliability of the cooling water flow associated with clogging events.

Overall Assessment of Alternative:

Fine mesh screens can meet performance requirements for entrainment, but impose a relatively high potential for operational issues associated with screen clogging. Mo rtality of ichthyoplankton removed from the screens is likely to be high. The cost of the screen panels, as well as the cost of a revamped intake structure to accommodate the additional screen area required, is ex tremely high. Space limitations may preclude the installation of adequate screen area. This technology is designed primarily for entrainment reduction and is far too costly a remedy for IM reduction, ther efore it is not recommended for further study.

• 1d – Angled and Modular Inclined Screens

Description:

Angled and inclined screens use standard flow-through trav eling screens set at an angle to the incoming flow. With these screens, the angle causes the fish to move toward the end of the screen, where a bypass facility returns the fish to the water body.

Technical Feasibility/Reliability

Angled screens have been used at Brayton Point. The in stallation requires considerably more space than conventional screens. Retrofit applications would likely r equire substantial modifications to the existing intake structure. The fish handling and return system require s independently induced flow, addi ng to the complexity of the system.

Cost Considerations:

Retrofit of angled or inclined screens should include t he need to revamp the intake structure, as well as the installation of an effective fish return system.December 2006 Document No.: 10735-002-400 Effectiveness:

Brayton Point has had mixed results with both diversio n and latent survival, depending on fish species. EPA reports survival efficiency ranging from 0.1 percent for bay anchovy to 97 percent for tautog. The difference in effectiveness between angled screens and conventional screens with fish return is not evident.

Potential for Other Adverse Effects:

The bypass flow can be substantial, re sulting in additional operating costs.

Overall Assessment of Alternative:

Angled or inclined screens are in lim ited use. Although they may be effective in reducing impingement mortality, it is not clear whether their performance di ffers from a conventional scr een. Because there is no apparent advantage, angled or inclined screens ar e not considered further in this analysis.

Technology Alternative 2 – Fixed Screening Devices

• 2a – Wedgewire Screens

Description:

Wedgewire screen is constructed of wire of triangular cr oss section such that the surface of the screen is smooth while the screen openings widen inwards. Fine me sh screens have slot spacing of less than 9.5 mm (3/8 inch) and are typically less than 3 mm. Slot size for coarse mesh screens is 9.5 mm or greater. The cylindrical screen design has been used at several powe r station applications. However, most of these applications have been for closed-cycle cooling systems.

A typical installation would include an array of tee sh aped cylindrical screens. If one-mm slot size were required, a station with a 500 MGD cooling water flow would require approximately 15 7-foot diameter by 23- foot long screens. The screens would be placed in the inta ke water body at a depth such that it would not present a hazard to navigation.

The screens would be cleaned periodically with an aut omatic compressed air system when located near shore. A large plenum structure would be added to the front of the intake structure to distribute the flow from the intake array. The existing intake structure would re main intact and functional. It could be used as a backup to the wedgewire screen system. The plenum structure woul d have openings that would allow flow to pass in case of screen clogging. Alternatively, wedgewire screen mu st be sized to minimize clogging and is subject to periodic manual cleaning.

For far-offshore applications, a compressed air cleaning sy stem is not practical. Under such conditions, the reliability of fine mesh screens is uncertain, and only coarse mesh wedgewire screens should be considered.

Technical Feasibility/Reliability:

Wedgewire screens have been widely used for hydropower diversion structures. The cylindrical screen structures have been used successfully for many years for water withdrawals up to 100,000 gpm. Withdrawals of larger quantities are rare. The wedgewire cylindric al screens have been implemented at only two relatively large power plants with once-through cooling systems: Ca mpbell Unit 3 on Lake Michigan, and Eddystone Unit 1 on the Delaware River. The high number of wedgewir e screens required for many plants is higher than hasDecember 2006 Document No.: 10735-002-400 been previously used and likely poses im practical logistical issues associ ated with placement in the bay or river.

The long-term reliability of the wedgewire screens of the one-millimeter size is unknown. Although some vendors have proposed construction materials which would prevent mussel or other biological growth on the screens, the requirements for biofouling control are unc ertain and could be substantial. The automatic backflushing would reduce screen fouling from both biological growth and suspended particulate matter. However, to be effective for screen cleaning, this system requires an ambient current to transport the removed particles from the vicinity of the screens. In waters with minimal current, debris accumulation may be excessive and backwashing ineffective. Small or negligible currents in the intake water body could make wedgewire screens impractical, especially fine-mesh screens.

In addition, if the screens were to be located at a di stance from the shore, considerable length of large diameter piping would be necessary to connect the screens to the existing cooling water system. Installation of such a system will result in signifi cant cost as well as potential disr uption of the site and the water body.

Cost:

The cost for the wedgewire screen alternative should c onsider the distance offs hore, needed piping, and airburst cleaning system. Operation and maintenance costs include two maintenance dives (6 days each) each year, replacement parts, and system monitori ng by facility staff (10 hours per week).

Effectiveness:

Wedgewire screens have been demonstrated to essentially eliminate impingement and, for smaller slot sizes, reduce larval entrainment. The 1-mm slot size has been demonstrated to reduce entrainment by over 80 percent at some facilities. However, achievement of such results is dependent on the presence of relatively high ambient currents that can sweep the plankton alo ng and past the screens. For application at the Stanton Station where entrainment is not a co mpliance consideration, a wide slot size could be utilized to help reduce through-screen velocity to below 0.5 fps and thereby qualifying for 316(b) compliance option #1.

Potential for Other Adverse Effects:

The primary adverse effect associated with this alternat ive is the potential for obstruction to navigation caused by multiple submerged structures in the water body near the plant. In addition, the presence of rock rip-rap around a large number of screen structures can result in a “reef effect,” causing the fish population density to increase in the vicinity of the screen structure. This phenomenon is more likely in cases where there is very little spawning habitat near the intake location.

Overall Assessment of Alternative:

The Missouri River may not provide sufficient depth near the Stanton CWIS to allow installation of wedgewire screens. Installation of any in-river technologies would pose a significant hazard to navigation. Additionally, extreme cold conditions during winter could cause exce ssive ice formation on the scr eens reducing their ability to provide cooling water to the station. The cost of this alternative is high and is strongly dependent on the number of screens needed and the length of new pipel ine construction needed to interconnect all of the screens and to build a common tunnel to the shoreline. Ho wever, due to the existing low intake velocity and the potential to reduce intake velocity slightly further through installation of wide slot screens, installation of wedgewire screens is recommended for further study through the CDS.December 2006 Document No.: 10735-002-400 • 2b – Perforated Pipes

Description:

With perforated pipes, water is drawn through perforations or slots in a pipe located in the water body. EPA included this technology in its discussion of intake te chnologies. However, perforated pipes have been used only in small water withdrawal applications. It also is subject to clogging and fouling. It also is similar in principal to wedgewire screens. Therefore, this technol ogy alternative will not be discussed further.

• 2c – Barrier Nets

Barrier nets are wide-mesh nets that are placed in front of the intake structure entrance. The nets are sized to prevent the fish from passing through , and low velocities are maintained at the net to allow affected fish to swim away. Barrier nets would be mounted on a frame that would allow ease of cleaning or replacement.

Technical Feasibility and Reliability:

Barrier net systems involve technologies that are in widespread use especially in freshwater systems. Construction techniques that would be used for thes e systems are commonplace. Maintenance requirements include routine cleaning of debris and/or net replacement . Deployment is often limited to certain seasons because of the potential for winter damage from icing and storms. Finally, placement of a barrier net at the intake has the potential to adversely affect boat traffic. Placement typically involves suspension from existing pylons or walls. Creation of a new set of anchors, etc. will complicate installation and increase costs.

Cost Considerations:

For typical power plants, the estimated capital cost for installation of barrier nets is $0.5M to $1.5M. The estimated operation and maintenance cost is approximat ely $50,000 per year for freshwater deployments. Operation and maintenance costs include monthly change out and annual deployment and removal.

Effectiveness:

Barrier nets have been shown to be effective for impinge ment reduction at a number of facilities. Greater than 90 percent reduction in impingement has been realized at a number of facilities. However, they are not effective in deterring fish eggs and larvae, or other pl anktonic organisms. There is the potential for clogging with debris; hence a routine cleaning operation is essent ial. Adequate area to allow low through net velocity (<0.5 ft/s, often <0.1 fps) is impor tant to prevent clogging and collapse.

Potential for Other Adverse Effects:

This alternative could pose l imitations on navigation in t he vicinity of the intake.

Overall Assessment of Alternative:

There have been a number of positive experiences with ba rrier nets for reduction in impingement, and the cost is very low compared to other technologies. However, considering the long, cold winter season in North Dakota, nets could only be deployed during warm months and removed each winter. The effectiveness of placing nets during warm months would need to be investigated against the results of the on-going IM monitoring study to determine the effectiveness of th is technology at Stanton. This alternative is recommended for further study.December 2006 Document No.: 10735-002-400 • 2d – Aquatic Filter Barrier System

Description:

Aquatic filter barrier systems are designed to completely enclose an existing intake structure and essentially filter the water drawn through the fabric to the intake structure. The best known manufacturer of aquatic filter fabric systems for power plant intake applications is Gunderboom. The Gunderboom system is a double panel, full water depth fabric curtain suspended from flotation billets at the water surface and secured in place by an anchoring system. The system includes mooring lines , ballast chain, anchoring system and an automated compressed air cleaning system. Automatic alarms and monitors may be installed in an appropriate control room to monitor the fabric alignment and system operation.

The standard design hydraulic loading rate of the Gunder boom fabric is 3 to 5 gp m per square foot with a generally recommended maximum range of 10 to 12 gpm per square foot. At the recommended design hydraulic loading and an assumed water depth of 15 feet, a length of fabric of more than one mile would be required for a 500 MGD cooling water flow. Therefore at a minimum, this alternative would require that a large area around the intake structure be encompassed by the fabric for most large power stations with oncethrough cooling.

Technical Feasibility/Reliability:

The technology and construction techniques required fo r this option have been full y implemented only at the Lovett Power Plant in New York State. Clogging of the Gunderboom is a routine maintenance issue. The length of fabric required would encompass a large area ar ound an intake structure. Aquatic filter barriers are not likely to withstand th e icing conditions encountered in the Gr eat Plains region. A Gunderboom would require seasonal deployment, increasing the operation and maintenance costs.

Cost Considerations:

The estimated capital cost of th e Gunderboom alternative is high com pared to other near-shore technologies. The operation and maintenance costs include the mobilizat ion and installation/demobilization and removal of the system each year. They also include regular underwa ter inspections of the filter curtain each month and one thorough underwater inspection each year.

Effectiveness:

Aquatic filter barriers have been demonstrated to be effe ctive in substantially reducing larvae entrainment and fish impingement losses at power station intakes on the Hudson River. As a result, the New York State DEC is a strong advocate of this technology for entrainme nt and impingement reduction. However, clogging and ambient conditions can increase the risk of fabric failure, rendering the system ineffective.

Potential for Other Adverse Effects:

Because this aquatic filter barrier app lication would require closing off much of the waterbody near the plant, navigation would be restricted. The potential for aquatic organisms to be impinged in the fabric is a concern.

Overall Assessment of Alternative:

Based on the logistical and potentia l navigation issues associated with the extensive area of the waterbody that would be encompassed by the aquatic filter fabric, oper ational issues associated with potential clogging of the fabric, potential damage from floating debris, and the costs associated with biannual installation and removal, it is not likely that this alternative would be practical in any once-through application with large flow rates, particularly at Stanton. Installation of aquati c filter barriers is not recommended for further study.December 2006 Document No.: 10735-002-400 • 2e – Porous Dams/Leaky Dikes

Description:

Porous dams, also known as leaky dams or leaky di kes, are filters constructed of stones surrounding the cooling water intake. The core of the dike is composed of gravel or stone which allows water to be drawn through it. The exterior of the dike is armored with larger rocks. The dam serves as a behavi oral and physical barrier to aquatic organisms. The reduced flow rate across the full face of the dam greatly reduces impingement, however, “hot spots” of high velocity ma y be present in local areas of high porosity, and its effectiveness in screening fish eggs and larvae is not well established.

Technical Feasibility and Reliability:

Because of its size, a porous dam constructed around an intake structure may not be practical in waterbodies of limited size, because of potent ial impacts to navigation.

Cost Considerations:

Because of its large size, a large part of the capital cost of a porous dam is ma terials (stone and gravel). Operation and maintenance would include routine main tenance and potentially heavy cleaning or dredging every 5 years.

Effectiveness:

If the surface area is sufficiently large, the porous dam intake structure could result in a lower impingement rate, but may not decrease the entrainment rate. Th e porous dam would decrease impingement due to low intake velocity across the dam face and the physical bar rier created by the stones used in the dam. The dam structure would need to be located such that its c onstruction does not impact known spawning beds. The presence of the stone could create spawning areas wh ere there were none and could actually serve to increase entrainment. Alternatively, potential spaw ning areas created by the porous dam may act as a restoration measure and increase the production of fish in the water body.

Potential for Other Adverse Effects:

Significant biofouling could be expected due to algae and aquatic weeds (e.g., watermilfoil). Biofouling of the porous dam would reduce plant cooling water intake rate. Fr azil ice formation should be expected in the winter months and the dam itself would be s ubject to structural damage from surf ace ice. The size of the porous dam is large, and its construction has the potential to damage fish spawning areas. In smaller waterbodies, a dam of sufficient size to effect ively reduce intake velocity could impede shipping and boating.

Overall Assessment of Alternative:

A porous dam will likely be effective for reduction in impingement if designed for low intake velocity. However, to achieve low intake velocity, the dam would have to be built well out into the river navigation channel making it impractical for this location. Installation of a porous dam is not recommended for further study.December 2006 Document No.: 10735-002-400 Technology Alternative 3 – Submerged Offshore Intake Structure

Description:

An offshore intake structure alternativ e would consist of a structure with velocity cap (or other technology such as wooden cribs or wedgewire screens), and a single pipeline in to the station. The size of the structures would be designed to achieve a nominal intake velocity of 0. 5 ft/s. The velocity cap on the structure provides horizontal flow that reduces the potential for fish impi ngement. The intake structures would be located in the water body at a water depth of at least 20 feet. The inta ke pipeline would be placed by either trenching or tunneling.

Technical Feasibility/Reliability:

The technology and construction techniques required for in stallation of submerged intake structures are well known and understood. Submerged intakes have been constr ucted at several facilities and have been shown to be reliable in the long term. Considerations for designing and constructing the alternative include 1) technology associated with sub-surface placement of the pipe and potential impacts to the bottom along pipeline route, 2) the length of pipeline needed to reac h sufficient depth, 3) prevention of fouling on the structure, 4) the potential for adverse impacts due to debris, and 5) the need to avoid obstruction of navigable waters.

Another technical consideration for the offshore intake stru cture alternative is that the intake water could have a reduced temperature which would potentially improve power plant performance.

Cost Considerations:

The estimated capital cost of subm erged offshore intake is highly dependent on the length of new pipeline needed. One 6-day dive per year would be required for maintenance.

Effectiveness:

The offshore intake structures could result in a lower im pingement rate if designed with low intake velocity and velocity cap. Suitable placement of the intake off-s hore may reduce the density of eggs and larvae subject to entrainment relative to an on-shor e location. The intake structure c onstruction could impact spawning beds. The presence of the intake structure and associat ed anchor stone and rip-rap could create new spawning areas that did not previously exist and co uld actually act to increase entrainment.

Overall Assessment of Alternative:

The Missouri River does not provide sufficient depth near the Stanton CWIS to allo w installation of offshore intake structures. Installation of any in-river technol ogies would pose a significant hazard to navigation. Installation of any offshore intake struct ure is not recommended for further study.

Technology Alternative 4 – Fish Diversion and Avoidance

• 4a – Louvers and Angled Bar Racks

Description:

Diversion devices are physical structures intended to guide fish away from and out of the intake flow. Examples of such devices include angled bar racks and louvers, which are m ade of a series of evenly spaced,December 2006 Document No.: 10735-002-400 vertical slats placed across a channel at an angle lead ing to a bypass area. The louvers create localized turbulence that the fish detect and avoid. The louver systems have been tested at hydroelectric facilities on rivers.

Typically, angled bar racks and louvers would be in semic ircular fashion around a shor eline intake or placed across the mouth of an intake canal. Louvers would be constructed of material compatible with the environment (for example, polyethylene slats for louv ers and nylon for nets), and would be mounted on a stainless steel frame, approximately 12 inches apart.

Technical Feasibility/Reliability :

Louver systems involve technologies that are in widesp read use. Construction tec hniques that would be used for these systems are commonplace. Maintenance requirem ents could be potentially extensive. Divers will likely be required to routinely clean and /or replace the bar racks or louver s. The potential for damage and clogging from ice and debris is real. Finally, placement of a louver at the intake has the potential to adversely affect boat traffic.

Cost Considerations:

The capital cost for installation of louvers should include consideration for debris loading and damage. Operation and maintenance costs include two 6-day dive s per year to clean and maintain the louvers.

Potential Effectiveness:

These diversion devices are not effective in deterring fish eggs and larvae, or other planktonic organisms. Louvers have been tested only in rivers with a substa ntial current velocity along the bank. They are most effective in diverting migratory fish from intakes in confined river channels, and therefore would be less effective in lakeside applications.

Potential for Other Adverse Effects:

This alternative could pose l imitations on navigation in t he vicinity of the intake.

Overall Assessment of Alternative:

Louvers/bar racks can effectively reduce impingement of some species of fi sh, but would not be effective for reducing entrainment. This alternative has relatively high probability of clogging as sociated with ice, debris, and biological growth. Because this technology is a permanent installation which could not be removed each winter, it would be subject to damage from floating ic e and subject to clogging from ice formation. This technology is not recommended for further study.

• 4b – Velocity Caps (installed on existing offshore intake)

Description:

A velocity cap is a cover placed on a vertical inlet of an offshore intake structure. The cover results in a horizontal flow to the intake, and may reduce impinge ment because fish tend to avoid rapid changes in horizontal flow. Intake velocities of 0.5 to 1.5 ft/s are common.December 2006 Document No.: 10735-002-400 Technical Feasibility/Reliability:

Installation of a velocity cap on an existing offshore in take may be limited because of water depth and potential interference with navigation. For some applications , a velocity cap may require routine inspection and maintenance to remove accumulated debris.

Cost Considerations:

Costs of installation of a velocity cap on an existing offshore intake should consid er intake modifications and materials of construction.

Potential Effectiveness:

Although velocity caps in new offshore intakes have been shown to result in reduced impingement, it is uncertain whether the reported reductions are due to the ve locity caps or the new offshore locations. Velocity caps should be designed to minimize intake velocity th rough the intake structure openings; a maximum intake velocity of 0.5 feet per second should be considered to meet the Phase II intake velocity threshold. In some cases, additional measures (e.g., intake screen impro vements, deterrent systems) may be needed to meet impingement performance goals. Velocity caps have no im pact on entrainment, although the off-shore location may result in lower entrainment levels compared to an on-shore calculation baseline intake configuration.

Potential for Other Adverse Effects:

The addition of a velocity cap to an exis ting intake may interfere with navigation.

Overall Assessment of Alternative:

Velocity caps are only pr actical for installation at existing in-river in take structures or as part of a new in-river intake structure. As with other in-river technologies , the hazard to navigation and potential for damage from floating ice make this an impractical technology for St anton. Velocity caps are not recommended for further study.

• 4c – Strobe Lights, Acoustic Deterrent, Bubbles, Chains

General Description:

Behavioral barriers are intended to cause fish to actively avoid entry into the intake flow. Examples include sound barriers, light barriers, air bubbl e curtains, chains and cables, and electrical barriers. They are often implemented in combination with other devices such as physical barriers (e.g., fish nets). The potential behavioral barriers are briefly described below.

Sound barriers consist of devices located at the intake stru cture, which create sound that repels the fish. Three types of underwater sound have been tested for this application: low-frequenc y infra-wave sound, lowfrequency sound generated by pneumatic/mechanical devic es, and transducer-generated sound covering a wide range of frequencies. Low frequency, high-intensity de vices have been shown to be effective. High frequency (125 kHz) devices have been reported to be e ffective in the Great Lakes. Pneumatic impact devices, “poppers”, and “hammers” are examples of devi ces that have been effective in reducing impingement of some fish such as alewife at power plant intake s. There is some concern that pressure waves from pneumatic devices may be harmful to nearby organisms. In most cases, the use of high-intensity, multifrequency sound has not been effective in repelling a wide range of fish species from intakes due to the diversity of species and sizes of species in the receiving water.December 2006 Document No.: 10735-002-400 Light barriers consist of a series of underwater lamps that em it a constant or inter mittent (strobe) beam of light. The effectiveness of light barriers as a deterrent has been variable, and even contradictory, in many studies. In some studies fish have been attracted to lig ht while in others they have been repelled. Constant light has been more effective than strobe light in gui ding young salmon whereas st robe light has been effective in repelling alewife and gizzard shad. Filtered mercury vapor light has been found to attract certain species of fish away from strobe lights in field studies in Europe. At the Nanticoke Generating Station on Lake Ontario, smelt, shad, white bass and shiner have been successfully guided away from intake trash racks using mercury vapor light. However, evidence of consistently reliabl e effectiveness for a wide range of fish species does not exist.

Air bubble curtains or screens consist of a series of diffus er pipes mounted on the base of the intake structure. The diffusers create a c ontinuous, dense curtain of bubbles, which can repel fish. Generally, the air bubble screens have not been successful. They are not effective at night and in turbid water. In one case, at Indian Point Generating Station on the Hudson River, t he air bubble screen actually attracted fish at night.

Chains or cables can be hung vertically from the top of the intake structure to form a ph ysical, visible barrier to fish. The results of studies of this behavioral ba rrier have been contradictory. The effectiveness of chain barriers is dependent on flow velocity, turbidity and illumi nation. Debris buildup on hanging chains can disrupt hydraulic flow patterns at the intake.

Electrical barriers consist of a series of electrodes at either side of the intake structure. These barriers have had limited success and can present a safety threat.

Technical Feasibility/Reliability:

All of the behavioral barrier systems are technically feas ible and reliable from the pe rspective of construction, operation, and maintenance. The behavioral barrier syst ems that have been implemented with the greatest frequency are sound and light barrier type systems. Each of these potential alternat ives would consist of a metal support structure constructed at the front of the intake, sound or light emitting devices mounted on the supports, a power supply, controllers, power cables an d mounting hardware. The construction and technology used for these alternatives have been regularly applied. To ensure long-term reliability of these systems, ongoing maintenance will be required. Maintenance of th e systems would include cleaning and replacement of light bulbs (for light barrier systems) and prev ention of corrosion of the supporting structure.

Cost:

The estimated capital cost of behavioral barriers (e.g ., a strobe light barrier system) is generally lower than other technologies. Operation and maintenance costs incl ude items such as the replacement of strobe lights each year using divers, and 10 hours per week of on-site monitoring by stat ion staff. Costs for other behavioral barrier systems would be similar.

Effectiveness:

Because these barriers rely on the ability of the organism to respond to a stimulus, they are not effective in protecting fish eggs and larvae, or other planktonic org anisms. In addition, the effectiveness of these barriers varies among species and across age groups within specie s. These barriers are most effective when a single species of fish of the same size and age is to be protected. Many the behavioral barriers have not been fieldtested so their effectiveness has been extrapolated fr om laboratory studies. None of these devices has been demonstrated to be consistently reliable in obtaining an avoidance response from a wide range of fish species. Therefore, installation of behavioral barriers would not result in reduction of entrainment, and a reduction in impingement is possible but uncertain.December 2006 Document No.: 10735-002-400 Potential for Other Adverse Effects:

A potential adverse effect of the behavioral barrier alternat ive is a slight potential for increased attraction of fish to the intake structure. Also, any structure installed near the intake has the potential to disrupt navigation.

Overall Assessment of Alternative:

Behavioral barriers may effectively divert specific fish species and therefore could be a component of an overall impingement mortality reduction. Based on site- and species-specific variation in response, pilot testing is likely to be necessary. One or more of the beha vioral barrier systems may merit further study after completion of the on-going IM study.

Technology Alternative 5 - Flow Reduction

• 5a – Variable Speed Pumps

Description:

Variable speed cooling water intake pumps are potentia lly useful for reducing c ooling water flow and the associated entrainment and impingement during peak periods of biological activity. The decrease in cooling water flow results in an increase in plant condenser delta T (temperature increase through the condenser) and discharge temperature. Therefore, variable speed pumps are most appropriate during cold water periods of the year (winter and spring) in temperate climates wher e an increase in discharge temperature will not cause a significant increase in biological effects or cause discharge temperatures in excess of maximum acceptable levels.

For other facilities, this alternative was considered wi th the assumption that variable speed pumps would be installed to decrease the cooling water flow by 25 perce nt during periods of potenti ally high entrainment and impingement. This alternative would require replacemen t of existing single speed drives with adjustable speed drives (ASD) on the circulating water pumps. An on-li ne condenser tube cleaning system is included in this alternative to alleviate tube fouling which could poten tially occur because of lower water flow rates.

Technical Feasibility and Reliability:

The replacement of the existing single speed drives with AS Ds is a technically feasible and reliable alternative. However, under full power production conditions using t he existing condensers for the units, this alternative, specifically a 25 percent reduction in flow, could reduce the reliability and efficiency of the entire system. Specifically, the reduction in flow through the condense rs could cause operational di fficulties (i.e., condenser tube fouling), cause decreased thermal efficiency in th e turbines, limit or reduc e maximum power production, require condenser replacement, and alter the thermal plume effects at the discharge.

Cost:

The estimated capital cost of the variable speed pump alternative is $0.5M per cooling water pump. This capital cost assumes that replacement of the exis ting condensers would not be required. Operation and maintenance costs are difficult to estimate without input from the individual stations regarding thermal efficiency as well as market rates. It should be noted t hat costs associated with losse s of thermal efficiency are likely to be partially offset by the gain in not operating the pumps at full capacity. This cost assumes that the plant could be operated at full capacity during reduced cooling water flow.December 2006 Document No.: 10735-002-400 Effectiveness:

The use of variable speed pumps to decrease the flow of cooling water through the intake would effectively reduce the entrainment and impingement in the system; how ever, the resulting increase in temperature in the discharge could increase thermal plume effects. The alter native would amount to a rela tively small reduction in flow – and corresponding reduction in impingement and entra inment effects – of approximately 25 percent for the entire plant during periods of time when the ASDs are in operation. Since the ASDs would not be used during the entire year, the overall reduction in impi ngement and entrainment would be substantially less than 25 percent.

Potential for Other Adverse Effects:

As noted above, reduction in cooling water flow durin g normal station output would result in an increased discharge Δ T value which could, in turn, cause altered thermal plume effects.

Overall Assessment of Alternative:

By itself, this alternative will not likely achieve performance goals for impingement reduction, though it may be considered as one component of an overall compliance plan . However, any reduction in intake volume would likely result in an increase in discharge temperature an d risk exceeding temperature limits set in the NPDES permit under Section 316(a). This alternative is re commended for further review during preparation of the CDS.

• 5b – Capacity Factor Reduction

Description:

A power plant can reduce impingement and entrainment by reducing cooling water requirements through reduced capacity factor of t he facility. This approach would require a co mmitment on the part of the facility to limit cooling water flow to a level below the design flow rate. Unless a very low capacity factor is intended, this approach will likely be used in c onjunction with other technologies to meet performance goals.

There is the potential that regulator y agencies will limit the applicability of this approac h for facilities with historically low capacity factor. Alt hough the calculation baseline is bas ed on design capacity, the commitment to set a capacity factor limi t by a facility with histor ically low capacity factor ma y be viewed as an inappropriate approach to meeting the performance goals unless a restriction is included in the plant NPDES permit.

Technical Feasibility and Reliability:

Reduced water flow rate will limit the power production rate based on thermodynamics as well as the thermal discharge limits for the facility.

Cost Considerations:

Reduction on capacity of a facility will have very large financial impact on the ability of a facility to generate revenue. The capital cost to implement this approach coul d involve installation of equipment to limit operations; however, record keeping may be all that would be re quired to demonstrate the fl ow reduction achieved.

Effectiveness:

A capacity factor reduction and resulting reduced fl ow rate should at least reduce impingement and entrainment in proportion to flow reduction. Seasonal di fferences in density of aquatic life would need to beDecember 2006 Document No.: 10735-002-400 considered to determine the overall annual reductions in impingement and entrainment from the calculation baseline.

Potential for Other Adverse Effects:

This approach reduces power generat ion capacity, which would have to be made up elsewhere.

Overall Assessment of Alternative:

If acceptable to the regulating agencies, this alternative may be a component of compliance. This alternative is recommended for further study during development of the CDS.

• 5c – Evaporative Cooling Towers

Description:

The existing cooling water system uses river wa ter pumped through a steam condenser and discharged back to the source water body. This type of system is generally referred to as an open cycle or once-through cooling system because the water simply passes through the c ondenser (no recirculation) where heat is transferred from the steam to the cooling water prior to discharge. Closed cycle systems recircul ate the cooling water in a closed piping system. The heated water from the condens er is cooled down in each cycle using evaporative cooling. This cooled water is then recirculated to the condenser to cool and condense the steam from the turbine. In the mechanical draft-cooling tower, fans ar e used to circulate air that flows against the heated water sprayed inside the tower. Cooled water is collected in the tower basin and returned to the condenser. Water must be introduced into the system at regular intervals to make up for losses due to blowdown and evaporation. The closed cycle evaporativ e cooling systems require a water withdrawal rate that is about 3 to 5 percent of the amount of water required in once-through cooling systems.

The makeup water flow for a mechanical draft-cooling towe r is typically less than 5 percent of the flow required for once-through cooling. The makeup flow would be pum ped to the circulating water system from the current intake structure.

Technical Feasibility and Reliability:

The technology proposed for this alternative is well known and has been implemented for similar power plants. However, this alternative requires substantial open spac e, consumes a substantial amount of electricity, and reduces the thermal efficiency of the system. In addit ion, the ability of the existing condensers to handle the higher pressures associated with the recirculating system is uncertain and could have a large effect on the costs for this alternative.

Costs:

The capital cost of the mechanical cooling tower altern ative is very high. Operation and maintenance costs are typically estimated to be in the millions of dollars per year, primarily due to addi tional fan and pump power demands and water treatment requiremen ts. Finally, the increased temperatur e of cooling water in the steam condensers will results in both efficiency and capacit y losses for the generating units. During the hottest summertime conditions when electricity demand is highest, the efficiency and capacity losses could be as high as 10 percent. This will result in the need to purchase replacement power at a premium because a public utility has an obligation to serve its customers and will be required to bear that expense.December 2006 Document No.: 10735-002-400 Effectiveness:

The mechanical draft cooling tower al ternative would effectively reduce both impingement and entrainment in proportion to the flow reduction, typically 95 percent or more. This technology meets both the impingement mortality reduction and entrainment reduction perfo rmance standards set by the 316(b) Phase II rule for existing facilities.

Other Potential Adverse Effects:

The primary adverse effects for the mechanical draft cooling tower alternative are associated with increased water vapor content in the immediate ar ea of the cooling towers. This will result in a visible plume for some periods and has the potential to result in fogging impacts . To reduce the potential for these effects, a plume abatement system would be employed. Because cooling to wer drift cannot be eliminated completely, the tower would be located as far as possible from electrical equi pment, off-site receptors, and sensitive vegetation. Space limitations may make it difficult to locate the cooling towers to minimize these effects. A cooling tower also imposes noise and aesthetic impac ts. Another significant environmental effect is that the decrease in efficiency means that more fuel is burned per unit of el ectrical energy output. Theref ore, a plant with cooling towers will have more emissions than a plant utilizin g an open cycle system. The increase in emissions will be proportional to the decrease in plant efficiency. Depending on the weather conditions, the nega tive effect on efficiency could be anywhere from 1 to 10 percent.

Overall Assessment of Alternative:

A cooling tower alternative would be effective for reduc tion of both entrainment and impingement mortality; however, due to the very high costs and limited space available for cons truction, this alternative is not considered as a part of the compliance.

• 5d – Dry Cooling

Description:

With a dry cooling system air is used as a heat sink to condense steam in the system. Cooling water is essentially eliminated. However, a dr y cooling system requires a large cooling surface, many cooling fans, and a more sophisticated steam ducting system, which would requi re extensive modifications to an existing facility. In addition, an annual average thermal efficiency penalty of 2 to 5 percent is likely for the power plant. During the hottest summertime conditions when electricity demand is highest, the efficiency and capacity losses could be well over 10 percent. Because of these high costs, dry cooling is not consider ed a part of the compliance for any existing facility.

Technology Alternative 6 – Restoration

Description:

The USEPA 316(b) regulations allo w the use of mitigation strategies for enhancing fish and aquatic biota populations to offset impingement and entrainment lo sses. These strategies typically involve habitat restoration methodologies, particularly the creation and improvement of important habitat types that support aquatic biota, as well as spawning and nursery areas. Alte rnatively, ENSR is aware of several fish-stocking efforts in the southern U.S. that are viewed as successful by all parties involved. Ideally, the restoration activity should result in mitigating the types of species that are affected by entrainment and impingement at the plant and result in quantifiable benefits near the station. Alternat ively, the rule allows for “out-of-kind” restoration, which might be simpler to institute and monitor.December 2006 Document No.: 10735-002-400 NDG&F operates a fish hatchery nearby for the purpos es of providing stock to the Missouri River and tributaries. Various additional fish and habitat restorat ion strategies could be considered for the Missouri River in association with the NDG&F and NDDH includi ng wetland creation or habitat creation.

The restoration process would involve the following ac tivities: 1) evaluation of impingement data to assess target species and associated habitat restoration strategi es; 2) selection of the most appropriate restoration strategies and areas for restoration; 3) implementation of selected restoration stra tegies; and 4) coordination with relevant resource agencies (e.g., NDDH, NDG&F, USFWS) to gain approval.

Technical Feasibility/Reliability

Each of the potential restoration methods has been used with success in a number of applications. Each of the restoration methods would require an assessment of whet her any conditions in the river would preclude longterm success. The potential for court-remanding of th e restoration measures also should be considered.

Cost

Annual costs associated with fish stocking (assumed to continue for ten years) range from $20,000 to $100,000.

Effectiveness

There is little existing quantitative information on using increases in biol ogical production at habitat areas to offset impingement and entrainment losses. Howeve r, restored habitat areas have been demonstrated to result in an increase in biota and spawning. Alternat ively, a well-designed stocking program may be able to provide a more direct replacement of important species on an adult-equivalency basis. It should be noted that restoration does not reduce the rate of impingement mortality at CWISs.

Other Adverse Effects

There are no likely adverse effect s of the restoration alternative.

Overall Assessment of Alternative

This alternative is technica lly feasible, has comparatively moderate cost s, and is likely to be effective (though at this point it is difficult to quant ify the degree of mitigation that would be obtained). The alternative also would provide an overall environmental benef it to the Missouri River. This alternative is recommended for more detailed analysis.December 2006 Document No.: 10735-002-400 

## Appendix B

EPA Cost EstimateTable B-1:US EPA-Estimated Compliance Costs based on the Model Facility Approach for the Section 316(b) Phase II Final RuleSource: Appendices A and B of the Final Rule in the Federal Register, July 9, 2004.Column 1Facility NameColumn 2Facility IDColumn 3Intake IDColumn 4EPAAssumedDesign IntakeFlow, gpm(xepa)mgd Column 5Capital CostColumn 6BaselineO&M AnnualCostColumn 7PostConstructionO&M AnnualCostColumn 8AnnualizedCapital + NetO&M UsingEPA DesignIntake Flow2(yepa)Column 12PerformanceStandardson whichEPA CostEstimatesare BasedColumn 13EPAModeledTechnology5Column 14DesignFlowAdjustmentSlope (m)1Stanton AUT0273 1 173,689250$994,534 $52,039 $208,703 298,263 I&E 2 0.86391The design flow adjustment slope (m) represents the slope that corresponds to the particular facility using the technology incolumn 3.2Discount rate = 7%.3Amortization period for capital costs = 10 years.4Amortization period of downtime and pilot study costs = 30 years.Note: Depending on the data provided, some facilities with multiple intakes were costed separately for each intake. In such cases, the facility should calculated the costs considered by EPA foreach intake using the steps below and sum. Note that some costs (e.g., construction downtime) are assigned evenly to each intake for convenience.5EPA Technology Codes:1. Addition of fish handling and return system2. Addition of fine mesh screens to an existing traveling screen system.3. Addition of a new, larger intake with fine-mesh screens and fish handling and return system in front of existing screen.4. Addition of passive fine-mesh screen system (cylindrical wedgewire) near shoreline with mesh width of 1.75 mm.5. Addition of fish net barrier system.6. Addition of an aquatic filter barrier system.7. Relocation of existing intake to a submerged offshore location with passive fine-mesh screen inlet with mesh width of 1.75 mm8. Addition of a velocity cap inlet to an existing offshore intake.December 2006 Document No.: 10735-002-400 

## Appendix C

Sampling Plan

### Impingement Monitoring Plan 2005-2006

Basin Electric, Leland Olds Station Great River Energy, Stanton Station Minnkota Power Cooperative, Inc., Milton R. Young Station

Prepared for:

Basin Electric Great River Energy Minnkota Power Cooperative, Inc

.

Prepared by:

ENSR 1601 Prospect Parkway

Fort Collins CO 80525

Project Number 10735-002-400

May 200510735-002-400 August, 2005 

### i 

### CONTENTS

1.0 INTRODUCTION.............................................................................................................. ........1-1

2.0 STATION DESCRIPTIONS .....................................................................................................2 -1

3.0 SOURCE WATER BODY INFORMATION.............................................................................3-1

4.0 FIELD AND LABORA TORY PROCEDURES ........................................................................4-1

5.0 DATA ANALYSIS ............................................................................................................. .......5-1

5.1 Fish Data ...................................................................................................................... .5-1

5.2 Plant Operating Data.....................................................................................................5-1

5.3 Impingement Estimates ................................................................................................5-2

6.0 QUALITY ASSURANCE/QUALI TY CONTROL PROCEDURES..........................................6-1

6.1 Mobilization ................................................................................................................... 6-1
6.2 Sample Collection .........................................................................................................6 -2
6.3 Recording Data ............................................................................................................. 6-2

6.4 Datasheets ................................................................................................................. ...6-2
6.5 Container Labeling........................................................................................................6 -3
6.6 Safety Precautions........................................................................................................6 -3
6.7 Collection of Biological Data .........................................................................................6-3

6.8 Deviations from QA/QC Plan or SOP...........................................................................6-4
6.9 Data Management ........................................................................................................6-5
6.10 Sample Tracking ........................................................................................................... 6-5

7.0 STUDY REPORT .............................................................................................................. .......7-1

APPENDIX A – BIBLIOGRAPHY10735-002-400 August, 2005 

### ii LIST OF FIGURES

2-1 Site Location Map.............................................................................................................. .....2-2
3-1 Fish Species Identified in the Garrison Reach ......................................................................3-3
3-2 Summary of Fish Collected at Stanton Station 1997-2004 ...................................................3-4
4-1 Impingement Collection Basket .............................................................................................4-2
4-2 Proposed Schedule of Sampling Events ...............................................................................4-4
4-3 Impingement Study Team......................................................................................................4-510735-002-400 August, 2005 

### 1-1 

### 1.0 INTRODUCTION

This impingement monitoring plan has been developed to facilitate the collection of aquatic organisms from the intakes of three operating power plants that draw water from the Missouri River. The three power plants are Basin Electric’s Leland Olds Station, Great River Energy’s Stanton Station, and Minnkota Power’s Milton R. Young Station. These stations withdraw water from the Missouri River for cooling purposes and are subject to compliance with the requirements of Phase II of Section 316(b) of the Clean Water Act. This impingement monitoring plan is one component of the Proposal for Information Collection (PIC) that will be submitted separately for each facility.

Phase II of Section 316(b) of the Clean Water Act requires plants that withdraw 50 million gallons a day (MGD) or more of cooling water from surface water bodies to reduce entrainment and/or impingement of aquatic organisms to specific minimum levels through retrofit or restoration, or demonstrate that such measures are not beneficial or are prohibitively expensive. A component of the initial phase of this compliance demonstration is to document or determine the baseline entrainment/impingement rates to support the selection of a compliance strategy and ultimately quantify and confirm its effects.

Implementation of the Phase II program and subsequent demonstration of compliance by individual plants are administered under federal and state NPDES programs. The North Dakota Department of Health (NDDH) has primacy for the administration of the state’s NPDES program and is responsible for overseeing and approving compliance activities.

These three stations all withdraw more than 50 MG D from surface water bodies and are subject to Section 316(b) requirements. Leland Olds Station and Stanton Station are located on the Missouri River, and the Milton R. Young Station has a cooling water intake structure (CWIS) on the Missouri River, though the station is located 13 miles south on Nelson Lake. Since each station withdraws less than 5 percent of the mean annual river flow, they are not subject to requirements to reduce entrainment. However, they are subject to the impingement reduction requirements. There are no historical or current data for impingement rates at any of the station intakes. Because North Dakota Game and Fish conducts biannual sampling of the river in the vicinity of the power plants, there are reliable and recent data on fish populations in this segment of the
Missouri River.

Because of the lack of impingement data, Basin Electric, Great River Energy, and Minnkota Power have decided to support a joint impingement monitoring study whose data can be utilized for all three stations. This plan provides the detailed procedures for the field, laboratory, and data10735-002-400 August, 2005 

### 1-2 analysis components of this year-long study. Its purpose is to ensure consistent and reliable data collection and analyses.

The overall purpose of this impingement monitoring study is to collect reliable and site-specific data on the rate of impingement of aquatic organisms at the cooling water intakes of these three power plants. The data will then be analyzed to determine the potential impact of impingement losses to resident populations of organisms in this segment of the Missouri River. The results of these analyses will be utilized to select the appropriate strategy for compliance with Section 316(b) requirements at each station.10735-002-400 August, 2005 

### 2-1 

### 2.0 STATION DESCRIPTIONS

All three stations have relatively similar intake configurations. Their locations on the Missouri River are presented in Figure 2-1 . The stations and intakes are briefly described below.

Leland Olds Station (LOS)

LOS has two operating units that generate approx imately 656 MW and withdraw approximately 330 MGD during normal operation. Each unit has a CWIS that includes two short concrete forebay (total of four forebays) that are essentially flush with the river bank. A spray header in front of each of the forebays is used in the winter to reduce ice build-up and in the winter, some of the warm water that has passed through the plant is returned to the forebays to raise the temperature of the incoming water and prevent ice formation. Also, during winter operation, the warm water discharge is moved to a location upstream of the intake structures to help minimize ice build-up. A submerged spray header is used to wash sediments away from the front of the forebays, as
necessary.

Water is pulled into the forebay s and through trash racks that exclude large objects. At each CWIS, water then flows through dual vertical traveling screens and to dual pumps. The 3/8-inch mesh traveling screens are cleaned with 125 psi wash sprays when the operator determines from visual evaluation that build-up is occurring. The screens are also equipped with pressure drop instrumentation – when the pressure drop across the screens exceeds a setpoint, the wash sprays are automatically operated. Wash water is sprayed through the screens and material that is washed off the screens flows to a sluiceway that returns the collected material directly to the
river.

LOS represents an intake configuration that EPA considers “baseline” (as defined at 40 CFR 125.93), i.e., the intake is located flush and parallel with the shoreline, withdraws water from the surface and shallow depths of the river and has traveling screens with 3/8” mesh and no type of fish return system. References to a “baseline” configuration throughout this document refer to the situation at LOS.

Stanton Station

Stanton Station has two operating units that generate approximately 172 MW and withdraw approximately 144 MGD during normal operation. Stanton Station’s intake design is very similar to LOS’s design except that each unit has a single concrete forebay and each of the forebays are somewhat longer, with a distance of approximately 40 feet from the river bank to the trash racks. In addition, the sluiceway from the traveling screens exits the pumphouse building and flows onto

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### 2-3 the ground adjacent to the building. The slope of this area allows water to flow approximately 30 feet back to the river. The majority of debris and material is collected on the ground and is periodically removed manually.

Milton R. Young Station

The Milton R. Young Station has two operating units that generate approximately 700 MW, and is located 13 miles south of the Missouri River on Nelson Lake. The station draws cooling water from Nelson Lake through two CWIS. Nelson Lake is provided make up water through a pipeline from a CWIS on the Missouri River, located approximately 5 miles downstream of LOS. The Missouri River CWIS has the capacity to withdraw 19.4 MGD with two pumps operating, but normally only operates one pump, which a capacity of 11.2 MGD. The Missouri River CWIS includes a single traveling screen that receives water through a covered forebay that is proportionally smaller than the LOS SWIS, and does not include warm water recirculation for winter operations. The screen wash return is through a sluiceway that empties directly back into
the river.

The sampling plan for the Nelson Lake CWIS will be addressed in a separate sampling plan
submittal to the NDDH.10735-002-400 August, 2005 

### 3-1 

### 3.0 SOURCE WATER BODY INFORMATION

The three power plant CWISs are located on the Garrison Reach of the Missouri River. This reach has been studied thoroughly with regard to aquatic species for many years by Federal and State agencies as well as other independent researchers. Over 17 reports on various aspects of the status of the fishery along the Garrison Reach have been researched during the development of this sampling plan (a bibliography of these sources is provided in Appendix A). Most significantly, North Dakota Game and Fish Department has conducted fish population studies in the Garrison
Reach since 1991. These studies involved biannual fish collection at seven locations in the Garrison Reach. One of these collection locations is offshore of the Stanton Station cooling water outfall, which is located just downstream of the Stanton CWIS and upstream of the LOS CWIS, and which is in a similar river regime as the Milton R. Young Station river CWIS, 4 miles downstream. The location of the North Dakota Game and Fish Stanton sampling point is identified

on Figure 2-1

.

Section 125.95(b)(3)(i)-(iii) of the Phase II Rule stipulates that the Impingement Characterization Study must include the following to support development of the CDS:

(i)”Taxonomic identifications of all life stages of fish, shellfish, and any species protected under Federal, State, or Tribal Law (including threatened or endangered species) that are in the vicinity of the cooling water intake structure(s) and are susceptible to impingement...”;

(ii)”A characterization of all life stages....including a description of the abundance and temporal and spatial characteristics in the vicinity of the cooling water intake structure(s), based on sufficient data to characterize annual, seasonal, and diel variations in impingement mortality......These may include historical data that are representative of the current ope ration of your facility and of biological conditions at the site”;

(iii)”Documentation of the current impingem ent mortality.....of all life stages....and an estimate of impingement mortality....to be used as the calculation baseline...... Impingement mortality.....samples to support the calculations......must be collected during periods of representative operational flows for the cooling water intake structure and the flows associated with the samples must be documented.”10735-002-400 August, 2005 

### 3-2 Figure 3-1 presents a complete list of all the fish species identified in the Garrison Reach from 1991 through 2003 1



### . Figure 3-2 presents the number of each species identified at the Stanton Station by North Dakota Game and Fish during sampling events in summer and in fall from 1997 through 2004. The second condition listed above will be addressed by the data collected by North Dakota Game and Fish since it is likely that fish populations and movement were at their highest levels in the months that were sampled. The impingement characterization study will provide additional species occurrence data for the entire year. The existing data have been used to identify the species of fish likely to be found during the impingement characterization study and will be utilized to analyze the potential impact of impingement in the study report and during completion of the CDS. Additional data collected by North Dakota Game and Fish and other organizations will be incorporated into the study as soon as it is made available.

The U.S. Fish and Wildlife Service has reportedly documented the occasional presence of the pallid sturgeon, an endangered species, in the Garrison Reach. While it is not expected that a pallid sturgeon specimen will be collected, it is possible. The U.S. Fish and Wildlife Service will be immediately contacted if such a specimen is collected and it will be provided to them for examination after it is documented for this study.

The data collected by North Dakota Game and Fish as well as other researchers provide a relevant and ongoing characterization of the biological conditions and populations in the river near the intake structures of the three power plants. The data are representative of current conditions and were collected using appropriate QA/QC procedures by agencies of the State of North Dakota. The Impingement Characterization Study as described in this Plan will comply with the third condition listed above and will complete the data set required by the rule. The applicants do not propose to collect additional source water body data.

1 North Dakota Fisheries Investigations, Aquatic Investigations of the Missouri Mainstream in North Dakota, by Jeff Hendrickson, North Dakota Game and Fish Department, March 2004.10735-002-400 August, 2005 

### 3-4 Total Number of Each Fish Specie Present at Stanton Sampling Site NDG&F Sampling 1997 – 2004
Summer Fall Bigmouth Buffalo 15 160 Black Bullhead 0 0 Black Crappie 0 0 Bluegill 0 0 Blue Sucker 15 8 Brown Trout 2 25 Brook Stickleback 0 0 Burbot 1 6 Common Carp 84 125 Channel Catfish 11 7 Cisco 0 7 Common Shiner 9 0 Cutthroat Trout 16 5 Emerald Shiner 39 142 Chinook Salmon 15 7 Fathead Minnow 0 1 Freshwater Drum 5 5 Goldeye 11 8 Golden Shiner 0 0 Johnny Darter 4 39 Largemouth Bass 0 0 Longnose Dace 0 1 Longnose Sucker 100 103 Northern Pike 25 8 Orange Spotted Sunfish 0 0 Paddlefish 3 0 Rainbow Smelt 3 14 Rainbow Trout 1 4 River Carpsucker 330 295 Smallmouth Buffalo 8 43 Sauger 38 34 Shorthead Redhorse 140 65 Smallmouth Bass 9 7 Shortnose Gar 3 7 Shovelnose Sturgeon 4 7 Spottail Shiner 0 3 Walleye 264 203 White Bass 50 38 White Sucker 389 409 Western Silvery Minnow 0 1 Yellow Perch 0 3 Totals 1,594 1,790



### Figure 3-2. Summary of Fish Collected at Stanton Station 1997-200410735-002-400 August, 2005 

### 4-1 

### 4.0 FIELD AND LABO RATORY PROCEDURES

Impingement sampling will begin in June 2005 and will continue for 1 year. For the first 3 months of the study, each of the three river intakes will be visited once every 2 weeks for collection activities. During each visit, two continuous (approximate) 12-hour biological samples will be
collected.

During each impingement sampling event, the operating vertical traveling screens will be rotated per each station’s standard operating procedures. Prior to the first 12-hour sampling period, plant operators will rotate and wash the screens and sluiceways to remove all existing debris and material. At the start of each sampling period, a metal basket with 3/8-inch square mesh will be placed in the sluiceway downstream of the traveling screens. The collection basket will be designed to fit precisely within the sluiceway so that all wash water containing fish and debris will travel through the basket and not around it, to ensure a complete sample. An approximate representation of the basket placement is shown in Figure 4-1 ; there will be slight variations of design and location depending on each station’s traveling screen operation. Plant operators will wash the traveling screens according to normal plant conditions. Because of the time needed to 1) wash the screens, 2) remove debris and fish fr om the collection baskets, and 3) travel between facilities, it will not be possible to collect samples representing exactly 12 hours. However, the total collection period will be approximately 24 hours and the actual collection times will be noted on the field data sheets.

At the end of the first 12-hour period, screens will be rotated and washed, with debris being retained by the collection basket. As water passes through the basket, sampling personnel will remove fish. After the screens have been washed, any remaining debris in the basket will be examined for fish. The basket will be cleaned and put back in place for the second 12-hour collection period. At the end of the second 12-hour period, the screens need to be washed (due to excessive buildup of debris and subsequent pressure drop of the cooling water stream), prior to completion of the 12-hour period, wash water will be passed through the basket and examined for fish; the intermediate washing will be documented. If debris buildup is extremely heavy and it is not possible to intercept all of the wash water, the time the wash occurred will be noted and the actual collection time will be documented on the field data sheet. Plant personnel will be trained and utilized for collection of fish if intermediate washing is required. Specimens will be kept in coolers until sampling personnel return to the site.

Fish will be separated from the debris, placed on ice, and examined soon after collection or transported in coolers back to Bismarck for evaluation. Fish that are dead (no visible movement of gills or fins) at collectiojn will be noted on data sheets (placed in a separate container, if necessary). Fish that may have been dead long before impingement (e.g., advanced10735-002-400 August, 2005 

### 4-3 decomposition, missing scales and eyes, excessive fungus, etc., as compared to other fish within a particular sample) will be noted on the laboratory data sheet. Fish will be identified by species, weighed (grams), and measured (minimum of total length in centimeters). All fish identifications will be conducted by experienced fisheries biol ogists, utilizing current taxonomic keys or publications. Since it is expected that the fish count for each collection event will be well below 100 individuals, each fish will be evaluated and counted. If there is an exceptionally large number of individuals of one or more species, and the total number of specimens collected exceeds 100, then subsampling will be allowed. For any one species, at least 20 individuals must be measured; these will be obtained in an unbiased fashion from the pool of available specimens. Unusually large or small specimens also will be measured. Biological metrics will not be collected on the remaining fish.

All fish from any given collection (i.e., from one plant during one collection period) will be digitally photographed (as a group) using a camera with a minimum resolution of 3.0 megapixels. All digital photographs will be stored on a CD and submitted with an annotated list at the end of the study period. A voucher collection will be made that will include at least one representative of each species. The representative specimen should be in good condition with little or no external damage. Voucher specimens may be frozen or stored in formalin/alcohol. Only one specimen from each species is needed in the voucher collection; all other collected fish can be discarded, unless they are being retained for quality assurance purposes (see Quality Assurance/Quality Control [QA/QC] Procedures). Unusual fish (fish with odd coloration, tumors, unidentified fish) will be kept in the voucher collection as well.

After three months of data are collected at the three intakes, the data among the stations will be compared for sample taxonomy, quantity, and general biological metrics. After the first quarter, the data will be presented to NDDH. If the data from the three stations are similar, a request will be made to NDDH to conduct biweekly sampling at one station for three more quarters with a single verification sampling event at the other two stations (conducted during the same week as the routine sampling event) once each quarter. At this time, it is proposed that the LOS be selected as the primary sampling location since its configuration is most similar to baseline. If the quarterly samples reveal a significant difference in quantity or taxonomy at either station, then biweekly sampling will be resumed at that station for the next quarter. The total study will encompass 26 sampling events or approximately one year. Figure 4-2 shows the proposed schedule of sampling events for the sampling year (dates shown are tentative and may be slightly modified due to weather or operating constraints).

Sampling will be conducted by WPC, a local environmental consulting firm and supervised by Dr. David Pillard, of ENSR. Dr. Steve Kelsch will be a technical advisor and will provide support for taxonomic identification and quality assurance. Figure 4-3 provides details on the sampling staff organization.IDTask Name1Meeting with NDDH2Sampling Plan Approval3Quarterly Data Evaluations8Sample and Data Collection9Leland Olds Station36Milton R. Young Station (first 3 months)44Milton R. Young Station57Stanton Station (first 3 months)65Stanton Station5/266/20%15222951219263101724317142128411182529162330613202741118251815222951219265121926291623307142128411182529162330JuneJulyAugustSeptemberOctoberNovemberDecemberJanuaryFebruaryMarchAprilMayJuneJulyA20052006Impingement Monitoring Study (Tentative)Page 1

### Study Leader

Dr. Dave Pillard (ENSR) Figure 4-3

Impingement Study Team

Sampling Team Leader

John Schulz (WPC)

Sampling Staff

Al Sandvol (WPC) Basin Electric Great River Energy Minnkota Power Cooperative Technical Advisor

Dr. Steve Kelsch University of North Dakota10735-002-400 August, 2005 

### 5-1 

### 5.0 DATA ANALYSIS

5.1 Fish Data

Field and laboratory data for each sample will be recorded on forms compatible for computer entry. Data will be entered into a spreadsheet after each collection event and will be compared against the hard copy laboratory data forms by a data analyst with experience in biological data collection. Errors will be corrected immediately. Since counts are expected to be low, there should be no need for data extrapolation. Data will be reviewed for consistency by QA/QC personnel at ENSR. Data anomalies will be identified and in vestigated before being accepted as valid and
usable.

Summaries of the number for each species collected will be presented in the spreadsheet by sampling period and by station.

5.2 Plant Operating Data

For each sampling period, hourly data regarding the number of circulating water pumps in operation per unit, use of warm water recirculation, plant load (MW), and intake temperature will be collected from plant personnel. Hourly cooling water volumes will be calculated based on the number of pumps in operation for each unit and then summed across each 24-hour sampling period to determine the total vo lume sampled. Daily cooling wa ter volumes also will be obtained from plant personnel in order to calculate weekly cooling water volumes.

In addition, a velocity reading will be taken at each intake during each sampling event using a hand-held velocity meter. The meter will be positioned, if possible, near the front of the forebays for a prescribed interval of time and the velocity will be measured. If access to the forebays is not possible, than velocity will be measured at another accessible location, possible upstream of the screens. The river stage or depth of water at the screens will be recorded by plant operators or by the sampling team – this in formation will be used to evaluate impingement data.

Other operating data that will be collected include the number of wash events during the sampling period and the number of times the collection basket was emptied, if required to maintain adequate flow through the screens or to keep the basket from overflowing or plugging.10735-002-400 August, 2005 

### 5-2 5.3 Impingement Estimates

Species-specific impingement estimates will be ca lculated on a weekly basis using the following
formula:

Weekly Estimate = Number of Fish Collected x Weekly Cooling Water Volume Cooling Water Volume Sampled

Weekly impingement estimates (sampled on a biweekly basis) will be multiplied to determine a monthly total estimate. At the end of the study, monthly frequency distributions will be developed for each species sampled. Confidence intervals and limits will be determined at the end of the study using appropriate statistical and data evaluation methods.10735-002-400 August, 2005 

### 6-1 

### 6.0 QUALITY ASSURANCE/QUA LITY CONTROL PROCEDURES

Prior to initiating monitoring, a detailed QA/QC Plan will be developed to ensure that accurate, consistent and traceable data are collected for the duration of the project. Elements of the QA/QC Plan can roughly be broken into five categories:

• Mobilization for Field Work;

• Sample Collection;

• Sample Processing;

• Data Management; and

• Sample Tracking.

6.1 Mobilization

Sampling will be conducted in accordance with the described biweekly schedule. A matrix will be developed showing target dates for conducting each component of the program. The matrix will include the time(s) of day sampling is to be performed. Designated plant contacts will be notified 1 week prior to each sampling event, with confirmation provided 24 to 48 hours in advance.

A Field Manager, Mr. John Schulz of WPC, Inc., in Bismarck, North Dakota, has been assigned to the project. It will be the responsibility of the Field Manager to ensure that all needed equipment and supplies are readied for each sampling event and that the gear is in proper operating condition. The Field Manager will develop a checklist of primary and backup equipment, supplies, datasheets, tools, field repair kits, safety equipment, and other necessary items for each type of sampling activity. Twenty-four hours prior to each sampling event, this gear will be assembled and verified against the checklist. To the extent practical, backup gear, replacement parts, and spare batteries will be included in the gear assembled for each sampling event.

The sampling team assigned by the Field Manager will review field safety issues and protocols prior to embarking on each trip. Each sampling team will be led and supervised by the Sampling Team Leader, who will be ei ther Mr. Schulz or Mr. Al Sandvol of WPC, Inc. The Sampling Team Leader (if different from the Field Manager for any given sampling event) will meet with the Field Manager and review procedures, target plants, and schedule. They also will review a list of plant personnel who will be on duty during the collect ion period. It is the responsibility of the Field Manager and sampling team to ensure that all assembled equipment is transported to the project site and properly stored and handled for the duration of the trip.10735-002-400 August, 2005 

### 6-2 Upon return from each sampling event, the Field Manager will ensure that all gear is cleaned, inspected, stored, repaired when necessary, and otherwise readied for the next event. Supplies will be restocked, as necessary.

6.2 Sample Collection

The Sampling Team Leader will be responsible for ensuring that all field activities are conducted in conformance with established standard operating procedures (SOPs) and safety procedures. The Sampling Team Leader will be responsible for ensuring that all mobile equipment and samples are returned in proper order to WPC for anal ysis. A Scientific Collection Permit will be obtained from North Dakota Game and Fish (NDGF) to allow the collection and transport of fish once they are removed from the bas kets at each facility. In the unlikely event that a threatened or endangered (T&E) species would be collected, the specimen will be retained for examination by NDGF and the U.S. Fish and Wildlife Service (USFWS). However, no additional permit or plan is required relative to the possibility of encountering a T&E species.

6.3 Recording Data

Recorded data represent the results of long hours spent in the field and are the first step in a lengthy analytical process. All field and laboratory personnel will adhere to the basic rules for recording information as described below:

• Legible writing in black, waterproof ink only with no erasures, write-overs, or cross-outs;

• Correction of errors with a single strike-out line followed by the recorder’s initials and date;

• Initialed and dated footnotes at the bottom of each page if further explanation of any corrections is needed; and

• Cross-outs on incomplete pages with an initialed and dated diagonal line.

6.4 Datasheets

All data will be entered on pre-printed, standardized datasheets at the time of sampling. Datasheets will be water proof, “ Rite in the Rain ® 

### ” or equivalent. Generic information, such as date, type of sampling, field team members, and weather conditions, will be included at the top of the form. Site-specific conditions, such as time of collection, physical parameters, and sample ID, will be recorded at the beginning of sample collection. Upon completion of sample collection, any unusual conditions that might have affected the quality of the sample will be documented. An10735-002-400 August, 2005 

### 6-3 explanation will be provided for any missing data. The datasheet will then be checked for accuracy by a second member of the field team prior to obtaining additional samples or moving to the next station. Any unusual physical conditions of the collection basket or area (e.g., broken basket) should be noted and documented with digital photographs.

6.5 Container Labeling

Biological samples will be placed in appropriate containers. Containers will be labeled with a sparate “stick-on” label or with a water-proof, felt-tip marker (e.g., Sharpie ® 

### ). The label will include, at a minimum the date and station ID (including Unit, if the plant has more than one unit), and whether fish were alive (visible movement) or dead at the time of collection. Additional information may include sample type, sample number, and sampler’s initials. If samples will need to be stored for several days before processing, than the latter information must also be recorded.

6.6 Safety Precautions

Appropriate safety gear will be worn and utilized for all field activities in accordance with plant safety rules and established safety plans.

6.7 Collection of Biological Data

At the lab, field samples will be logged in, sorted by date and type, and stored in a safe, secure location for processing. Appropriate reference li terature and electronic databases will be made available to assist in taxonomic determinations. At least once per month for the first quarter and once per quarter for the remaining project time, fish collected form at least one of the plants (no less than 20 fish or all fish if <20 collected) will be reviewed by a second qualified taxonomist to ensure consistency in identifications. Should ther e be disagreement between the two taxonomists, supporting confirmation from outside experts will be sought. Samples of all problematic taxa will be delivered to an independent expert for identification/verification.

Length measurements of fish will be made using a measuring board consisting of a linear metric scale secured to a flat wooden or plastic base with a fixed head piece. Fish will be measured by positioning the body on the right side, head facing the observer’s left, and fish mouth closed. Total length will be measured as the distance from the anterior-most portion of the head or jaws to the extreme tip of the caudal fin. If the caudal fin is bi-lobed, the lobes will be squeezed together and measured to the posterior most tip of the combined lobes. Standard length will be measured from the anterior-most portion of the head or jaws to the hypural plate (posterior most portion of the caudal region).10735-002-400 August, 2005 

### 6-4 Representative specimens of problematic species will be identified to the lowest practicable taxon and preserved for more thorough identification. Freezing is adequate for short-term preservation, provided freezing will not distort the body as to make it difficult to identify. For longer-term storage, a chemical preservative is preferred. For fish greater than 150 mm that are being preserved chemically, an incision about 30 mm in length will be made along the abdominal body wall on the right side of the fish to ensure penetration of fixative into the body cavity. Fish will remain in buffered formalin (10 percent with CaCO 3 

### ) for several days to ensure adequate fixation of tissues.
After the fish have be en thoroughly fixed, the buffered formalin will be removed and the specimens soaked in fresh water for 48 hours with at least one change of water. After 48 hours all water will be discarded and 40-percent isopropyl alcohol or 70-percent ethanol added to the collection container for permanent preservation.

All data generated during the processing of samples will be recorded on standardized lab bench sheets. Prior to processing each sample, pertinent information on the container labels will be transferred to the bench sheet to ensure proper sample tracking. If the sample is to be reviewed as part of the project QA process, it be labeled with a discrete sample number and the name of the processing taxonomist and stored for QA purposes until the data for that sampling event can be evaluated. Once a QA review is conducted and the data are acceptable, the sample will be disposed of. If the data are not acceptable (e.g., due to errors or anomalies inconsistent with previous data), the QA reviewer and the original taxonomist will reexamine the data and determine the cause of any discrepancies. The QA reviewer will then document the discrepancy and steps taken towards resolution and prevention of the future errors. In addition, if data from any event are deemed unacc eptable, a sample from the next event will be retained for QA review, even if samples from that event were not scheduled to be examined by a second taxonomist. reexamination of a representative number of pr eviously identified samples will be made by a different taxonomist to verify previous identifications and numerical information. Greater than 5 percent discrepancy in taxonomic identification between initial and QA analyses will require reexamination of all samples from a particular sampling event. Discrepancies in numerical information (weight and length) will be interpreted in light of changes associated with storage methods (e.g., shrinkage due to preservatives). However, suspicious discrepancies in biological
metrics also will necessitate a r eexamination of all sa mples from that particular sampling event.

6.8 Deviations from QA/QC Plan or SOP

Examples of failures in sampling methods and/or deviations from sampling requirements include but are not limited to such things as sample container spillage or breakage, gear malfunction, equipment failure, and unusual site conditions that prevent sampling. Failures or deviations from the QA/QC Plan or SOP will be fully documented on the field datasheet and reported to the Project Manager. The Project Manager will determine if the deviation from established protocol10735-002-400 August, 2005 

### 6-5 compromises the validity of the resulting data. The Project Manager will decide whether to accept or reject data associated with the sampling event based on his/her best professional judgment and will determine whether the absence of specific data will significantly affect analytical objectives of the project. In cases where missing data are likely to impact the ability of the project team to draw reliable inferences regarding plant effects, the Project Manager will require that sampling be repeated.

6.9 Data Management

Field datasheets and lab bench sheets will be placed in labeled folders for input into an electronic database maintained by the identification lab. Prior to study initiation, the Field Manager or assignee will review the forms for completeness and accuracy. If it becomes apparent early in the project that additional data need to be collected, the data sheets will be modified appropriately. Each form will have a signature an d date block to track data proce ssing. After the da ta have been entered into the database, the data forms will be signed, dated, and returned to the folder for verification. Printouts of entered data will be verified against corresponding field datasheets and lab bench sheets to ensure that all information has been accurately transferred. Missing
information will be added and inaccurate information corrected. The forms will be initialed and dated by the verifying par ty. Following data verifica tion, the original data forms will be segregated by sampling date and type and archived for the life of the project.

6.10 Sample Tracking

Proper sample handling and custody procedures are required to ensure the integrity of samples from sample collection through data analysis. For samples collected by field personnel, that do not leave the possession of field personnel/taxonomists, no custody documentation is required other than collection data documented on field and laboratory data sheets. However, if samples are retained for QA purposes and those samples are sent via courier to another location, a number of forms will be used for chain-of-custody document ation. Upon arrival at the laboratory for QA examination, all samples will be received and logged in using a Sample Receipt Log, which will include the following information:

• Project Name;

• Field Team Leader;

• Date of Collection;

• Time of Collection;

• Site Identification;

• Type of Sample;

• Name of collector(s);10735-002-400 August, 2005 

### 6-6 • Name of Recipient; and

• Time/Date of Receipt.

The Project Manager or assignee will develop a master list of all samples, which will be used to track the progress of the field sampling program. Appropriate blocks for each sample will be checked off as each sample is collected, processed, analyzed, and the data entered into the computer. Each month, the Project Manager will review the master list and evaluate whether sample collection and processing is progressing in conformance with established schedules. Missing information will be reconciled and appropriate corrective measures taken, where
warranted.

All failures associated with sample receipt proced ures will be immediately reported to the Project Manager. These include but are not limited to things such as lost samples, deviations from SOP and/or QA/QC requirements, incomplete documentation, possible tampering of samples, and broken or spilled samples. The Project Manager will determine if these issues have compromised the validity of the resulting data or will impede analytical objectives. The Project Manager will decide how best to address identified problems. Possible courses of action include 1) document and proceed, 2) redo the entire sampling event, or 3) selectively analyze the samples. The effect(s) of all identified problems on project objectives and any related corrective measures will be documented in QA reports furnished to the client.10735-002-400 August, 2005 

### 7-1 

### 7.0 STUDY REPORT

When this study is completed, a report will be prepared which includes field and laboratory methodologies, raw data, monthly organism and operating data summaries, and detailed results and conclusions sections. This report will become part of each station’s Comprehensive Demonstration Study (CDS) and will be used to support the stations’ selected compliance
program.

### APPENDIX A
BIBLIOGRAPHY

### BIBLIOGRAPHY

Berry, C. R. and B. A. Young. 2001. Introduction to the benthic fishes study. Volume 1 of Population
structure and habitat use of benthic fishes al ong the Missouri and lower Yellowstone rivers. U.S. Geological Survey, Cooperative Research Units, South Dakota State University, Box 2140b, Brookings, South Dakota 57007. charles_berry@sdstate.edu

.

Berry, C. R., D. L. Galat, and M. L. Wildhaber. 20 01. Fish distribution and abundance. Volume 3 of Population structure and habitat use of benthic fishes along the Missouri and Yellowstone rivers. U.S. Geological Survey, Cooperative Research Units, South Dakota State University, Box 2140b, Brookings, South Dakota 57007. charles_berry@sdstate.edu

.

Dieterman, D. J., M. P. Ruggles, M. L. Wildhaber, and D. L. Galat, editors. 1996. Population Structure and Habitat Use of Benthic Fishes Along the Missouri and Lower Yellowstone Rivers. 1996 Annual Report of Missouri River Benthic Fish Study PD-95-5832 to U.S. Army Corps of Engineers and U.S. Bureau of Reclamation.

Dieterman, D.J. 2000. Spatial Patterns in Phenotypes and Habitat Use of Sicklefin Chub, ( Macrhybopsis meeki ) in the Missouri and Lower Yellowstone Rivers. Doctoral Dissertation, University of Missouri-Columbia, Columbia, MO 185 p.

Everett, S. R., D. L. Scarnecchia, and L. F. Ryckm an. 2004. Distribution and habitat use of sturgeon chubs ( Macrhybopsis gelida ) and sickle-fin chubs (M. meeki) in the Missouri and Yellowstone Rivers, North Dakota. Hydrobiologia 527: 183-193.

Galat, D. L., M. L. Wildhaber, and D. J. Dieterman. 2001. Spatial patterns of physical habitat. Volume 2 of Population structure and habitat use of benthic fishes along the Missouri and lower Yellowstone rivers. U.S. Geological Survey, Cooperative Research Units, University of Missouri, 302 ABNR Bldg., Columbia, Missouri 65251-7240. galatd@missouri.edu

.

Galat, D., R. White, C. Pierce, L. Sappington, D. Scarnecchia, M. Ruggles. Missouri River Benthic Fish Study. http://wfs.sdstate.edu/units/fishes.html . 8 pp.

Hendrickson, J. C. 2004. North Dakota Fisheries In vestigations. Aquatic Invest igations of the Missouri Mainstem in North Dakota. Report of the North Dakota Game & Fish Department, Bismarck, North Dakota: 85 pp.

Hesse, L. W., J. C. Schmulbach, J. M. Carr, D. D. Keenlyne, D. G. Unkenholz, J. W. Robinson, G. E. Mestl. 1989. Missouri River Fishery Resources in Relation to Past, Present, and Future Stresses, p. 352-371. In D.P. Dodge [ed.] Proceedings of the International Large River Symposium. Can. Spec. Publ. Fish. Aquat. Sci. 106.

Hesse, L. W. and W. Sheets. 1993. The Missour i River Hydrosystem. Fisheries 18(5): 5-14.

### Neel, J. K. 1978. Life in the Missouri River with Warming by 676 Megawatts Gross Steam Generated Power Production. Prepared for Basin Electric Power Cooperative.

Pegg, M. A. 2000. Hydrological variation along the Missouri River and its effect on the fish community. Doctoral Dissertation, Iowa State University, Ames, IA. 141 pp.

Pierce, C. L., C. S. Guy, P. J. Braaten, and M. A. Pegg. 2001. Fish growth, mortality, recruitment, condition and size structure. Volume 4 of Population structure and habitat use of benthic fishes along the Missouri and lower Yellowstone rivers. US. Geological Survey, Cooperative Research Units, Iowa State Universi ty, Science Hall II, Ames, Iowa 50011. cpierce@iastate.edu

.

Power, G. 1993. The Missouri River System’s “Other” Fish. ND Outdoors, August, p. 6-9.

Power, G., J. C. Hendrickson, J. D. Lee, and F. Ryckman. 1994. North Dakota Fisheries Investigations, Missouri River System Fishery Reference and Operational Management Document. NDG and F Dept., 100 North Bismarck Expressw ay, Bismarck, ND, 58501-5095. 72 pp.

Power, G. 1995. River Fish . ND Outdoors, March, p. 13.

Power, G. 1998. The Missouri River in North Dakota (Garrison Reach) – A Report to the Director, Official Department Position Papers, Game and Fish Department, North Dakota: 7 pp.

Welker, T. L. 2000. Ecology and Structure of Fish Communities in the Missouri and Lower Yellowstone Rivers. Doctoral Dissertation, University of Idaho, Moscow, ID. 232 p.

Young, B. A., T. L. Welker, M. L. Wildhaber, C. R. Berry, and D. Scarnecchia, editors. 1997. Population Structure and Habitat Use of Benthic Fishes along the Missouri and Lower Yellowstone Rivers. 1997 Annual Report of Missouri River Benthic Fish Study PD-95-5832 to the U.S. Army Corps of Engineers and the U.S. Bureau of Reclamation.

Young, B. A. 2001. Intraspecific Variation among Emerald Shiners ( Notropis atherinoides ) of the Missouri River. Doctoral Dissertation, South Dakota State University, Brookings, SD. 140 p.December 2006 Document No.: 10735-002-400 

## Appendix D

Bibliography of Sources Used for Source Water Body ReviewDecember 2006 Document No.: 10735-002-400 Berry, C. R. and B. A. Young. 2001. Introduction to the benthic fishes study. Volume 1 of Population structure and habitat use of benthic fishes along the Missouri and lower Yellowstone rivers. U.S. Geological Survey, Cooperative Research Units, South Dakota State Un iversity, Box 2140b, Brookings, South Dakota 57007. charles_berry@sdstate.edu.

Berry, C. R., D. L. Galat, and M. L. Wildhaber. 2001. Fish distribution and abundance. Volume 3 of Population structure and habitat use of benthic fishes along th e Missouri and Yellowstone ri vers. U.S. Geological Survey, Cooperative Research Units, South Dakota State University, Box 2140b, Brookings, South Dakota 57007. charles_berry@sdstate.edu.

Dieterman, D. J., M. P. Ruggles, M. L. Wildhaber, and D. L. Galat, editors. 1996. Population Structure and Habitat Use of Benthic Fishes Along the Missour i and Lower Yellowstone Rivers. 1996 Annual Report of Missouri River Benthic Fish Study PD-95-5832 to U. S. Army Corps of Engineers and U.S. Bureau of Reclamation.

Dieterman, D.J. 2000. Spatial Patterns in Phenotypes and Habitat Use of Sicklefin Chub, (Macrhybopsis meeki) in the Missouri and Lower Ye llowstone Rivers. Doctoral Dissert ation, University of MissouriColumbia, Columbia, MO 185 p.

Everett, S. R., D. L. Scarnecchia, and L. F. Ryckm an. 2004. Distribution and habitat use of sturgeon chubs (Macrhybopsis gelida) and sickle-fin chubs (M. meek i) in the Missouri and Yellowstone Rivers, North Dakota. Hydrobiologia 527: 183-193.

Galat, D. L., M. L. Wildhaber, and D. J. Dieterman. 2001. Spatial patterns of physical habitat. Volume 2 of Population structure and habitat use of benthic fis hes along the Missouri and lower Yellowstone rivers. U.S. Geological Survey, Cooperative Research Units, University of Mi ssouri, 302 ABNR Bldg., Columbia, Missouri 65251-7240. galatd@missouri.edu.

Galat, D., R. White, C. Pierce, L. Sappington, D. Sc arnecchia, M. Ruggles. Missouri River Benthic Fish Study. http://wfs.sdstate.edu/units/fishes.html. 8 pp.

Hendrickson, J. C. 2004. North Dakota Fisheries Investigations. Aquati c Investigations of the Missouri Mainstem in North Dakota. Report of the North Dakota Game & Fish Department, Bismarck, North Dakota: 85 pp.

Hesse, L. W., J. C. Schmulbach, J. M. Carr, D. D. Keenlyne, D. G. Unkenhol z, J. W. Robinson, G. E. Mestl. 1989. Missouri River Fishery Resources in Relation to Past, Present, and Future Stresses, p. 352-371. In D.P. Dodge [ed.] Proceedings of the International Large River Symposium. Can. Spec. Publ. Fish. Aquat. Sci. 106.

Hesse, L. W. and W. Sheets. 1993. The Missouri River Hydrosystem. Fisheries 18(5): 5-14.

Neel, J. K. 1978. Life in the Missouri River with Warming by 676 Megawatts Gross Steam Generated Power Production. Prepared for Basin Electric Power Cooperative.

Pegg, M. A. 2000. Hydrological variation along the Mis souri River and its effect on the fish community. Doctoral Dissertation, Iowa St ate University, Ames, IA. 141 pp.

Pierce, C. L., C. S. Guy, P. J. Braaten, and M. A. Pegg. 2001. Fish growth, mortality, recruitment, and condition and size structure. Volume 4 of Population structure and habitat use of benthic fishes along the Missouri and lower Yellowstone rivers. US. Geological Survey, Cooperative Research Units, Iowa State University, Science Hall II, Ames , Iowa 50011. cpierce@iastate.edu.December 2006 Document No.: 10735-002-400 Power, G. 1993. The Missouri River System’s “Other” Fish. ND Outdoors, August, p. 6-9.

Power, G., J. C. Hendrickson, J. D. Lee, and F. Ry ckman. 1994. North Dakota Fi sheries Investigations, Missouri River System Fishery Reference and Oper ational Management Document. NDG and F Dept., 100 North Bismarck Expressways, Bismarck, ND, 58501-5095. 72 pp.

Power, G. 1995. River Fish. ND Outdoors, March, p. 13.

Power, G. 1998. The Missouri River in North Dakota (G arrison Reach) – A Report to the Director, Official Department Position Papers, Game and Fish Department, North Dakota: 7 pp.

Welker, T. L. 2000. Ecology and Structure of Fish Co mmunities in the Missouri and Lower Yellowstone Rivers. Doctoral Dissertation, University of Idaho, Moscow, ID. 232 p.

Young, B. A., T. L. Welker, M. L. Wildhaber, C. R. Berry, and D. Scarnecchia, editors. 1997. Population Structure and Habitat Use of Benthic Fishes along the Missouri and Lower Yellowstone Rivers. 1997 Annual Report of Missouri River Benthic Fish Study PD-95-5832 to the U.S. Army Corps of Engineers and the U.S. Bureau of Reclamation.

Young, B. A. 2001. Intraspecific Variation among Emer ald Shiners (Notropis atherinoides) of the Missouri River. Doctoral Dissertation, South Dakota State University, Br ookings, SD. 140 p.December 2006 Document No.: 10735-002-400 

## Appendix E

Agency Consultation Documentation