## SALT RIVER PROJECT NAVAJO GENERATING STATION – UNITS 1, 2, 3

SCR AND BAGHOUSE CAPITAL COST ESTIMATE REPORT

SL-010214 Revision D

Prepared By:

Project No. 12656-001 August 17, 2010SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 NOTICE

This Document was prepared by Sargent & Lundy, L.L.C., expressly for the sole use of Salt River Project in accordance with the agreement between S&L and Client. This Deliverable was prepared using the degree of skill and care ordinarily exercised by engineers practicing under similar circumstances. Client acknowledges: (1) S&L prepared this Deliverable subject to the particular scope limitations, budgetary and time constraints, and business objectives of the Client; (2) information and data provided by others may not have been independently verified by S&L; and (3) the information and data contained in this Deliverable are time sensitive and changes in the data, applicable codes, standards, and acceptable engineering practices may invalidate the findings of this Deliverable. Any use or reliance upon this Deliverable by third parties shall be at their sole risk.i SL-010214 Revision D



## NAVAJO GENERATING STATION SCR AND BAGHOUSE CAPITAL COST ESTIMATE

CONTENTS
Section Page

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### EXECUTIVE SU MMARY................................................................................................... ES-1

1. General Plant D escription ........................................................................................ 1-1 1.1 Description of Existing Plant........................................................................................ 1-1 1.2 Overview of Proposed Air Quality Control Systems (AQCS) ...................................... 1-1



### 2. Design Basi s.............................................................................................................. 2-1 2.1 General........................................................................................................................ 2-1 2.2 Meteorological Criteria ................................................................................................ 2-3 2.3 Industry Codes and Standards.................................................................................... 2-3 2.4 Supporting Documents................................................................................................ 2-3



### 3. Plant Mechanical System s and Equipm ent............................................................. 3-1 3.1 Service Water System................................................................................................. 3-1 3.2 Potable Water System................................................................................................. 3-1 3.3 Fire Protection Systems .............................................................................................. 3-2 3.4 Plant and Instrument Air System................................................................................. 3-2 3.5 Flue Gas System......................................................................................................... 3-3 3.6 Sorbent Injection System ............................................................................................ 3-7 3.7 SCR............................................................................................................................ . 3-8 3.8 Pulse-Jet Fabric Filter (Baghouse)............................................................................ 3-10



### 4. Plant Electrical System s and Equipm ent................................................................ 4-1 4.1 Codes and Standards.................................................................................................. 4-1 4.2 Electrical Power Supply Systems................................................................................ 4-1 4.3 Basic Electrical System............................................................................................... 4-1 4.4 Auxiliary Power System Performance......................................................................... 4-2 4.5 Auxiliary Power System Equipment ............................................................................ 4-4 4.6 DC Power Supply System........................................................................................... 4-5 4.7 Uninterruptible AC Power System............................................................................... 4-6 4.8 Electrical Control and Protection................................................................................. 4-6 4.9 Communication System .............................................................................................. 4-6 4.10 Lighting and Maintenance Power System................................................................... 4-6 4.11 Grounding System....................................................................................................... 4-7 4.12 Lightning Protection System........................................................................................ 4-7 4.13 Cathodic Protection System........................................................................................ 4-7 4.14 Freeze Protection Systems ......................................................................................... 4-7 4.15 Auxiliary Power Requirements .................................................................................... 4-7ii SL-010214 Revision D



## CONTENTS, CONT.
Section Page

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 5. Plant Control Systems and Equipm ent ................................................................... 5-1 5.1 General........................................................................................................................ 5-1 5.2 SCR Option ................................................................................................................. 5-1 5.3 SCR and Baghouse Option......................................................................................... 5-2



### 6. Project Sche dule ....................................................................................................... 6-1 6.1 introduction.................................................................................................................. 6 -1 6.2 Project Milestones – SCR Option................................................................................ 6-1 6.3 Project Procurement – SCR Option ............................................................................ 6-2 6.4 Project Milestones – SCR and baghouse Option........................................................ 6-3 6.5 Project Procurement – SCR with Baghouse ............................................................... 6-4



### 7. General Arrangement Featur es................................................................................ 7-1 7.1 Common...................................................................................................................... 7-1 7.2 SCR Option ................................................................................................................. 7-1 7.3 SCR and Baghouse Option......................................................................................... 7-2



### 8. Utility Relo cation....................................................................................................... 8-1 8.1 Plant Utilities................................................................................................................ 8-1



### 9. Plant Econom ics ....................................................................................................... 9-1 9.1 Basis of Cost Estimates .............................................................................................. 9-1 9.2 Capital Cost Estimates................................................................................................ 9-3 9.3 Budgetary Quotes ....................................................................................................... 9-4 9.4 O&M Costs.................................................................................................................. 9-6 9.5 Total Annual Costs.......................................................................................9-7



### 10. Construction and Cons tructibilit y ......................................................................... 10-1 10.1 Construction Site Plan............................................................................................... 10-1 10.2 Installation Methodology............................................................................................ 10-2 10.3 Startup and Commissioning ...................................................................................... 10-5iii SL-010214 Revision D



## TABLES
No./Title Page

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Table ES-1. Summary of SCR Only Capital Cost Estimate................................................................ES-3 Table ES-2. Summary of SCR Only - With Dry Sorbent Injection-Capital Cost Estimate...................ES-4 Table ES-3. Summary of 2007 Capital Cost Estimate-SCR Only (Including Outage Costs)..............ES-4 Table ES-4. Summary of SCR and Baghouse Capital Cost Estimate ................................................ES-5 Table ES-5. Summary of 2007 Capital Cost Estimate-SCR & Baghouse (Including Outage Costs)..ES-5
Table ES-6. Levelized Annual Costs ............................................................................................. .....ES-6

Table 2-1. SCR Design Criteria Summary......................................................................................... ....2-1 Table 4-1. Predicted Auxiliary Power Consumption............................................................................... 4-8 Table 6-1. SCR Option Schedule Milestones ...................................................................................... ..6-1 Table 6-2. Unit 3 SCR Option Critical Path..................................................................................... .......6-2 Table 6-3. SCR and Baghouse Option Schedule Milestones ................................................................6-3 Table 6-4. Unit 3 SCR and Baghouse Option Critical Path....................................................................6-4 Table 9-1. Total Estimated Capital Cost Summary................................................................................ 9-4 Table 9-2. Conceptual O&M Costs (on a per Unit Basis) ......................................................................9-7
Table 9-3. Levelized Annual Costs....... ..................................................................................9-8iv SL-010214 Revision D



## APPENDIXES

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Appendix A. Design Basis Appendix B. Capital Cost Estimate Equipment List Appendix C. Climate Data Appendix D. Piping and Instrumentation Diagrams Appendix E. Crane Placement Appendix F. Electrical Single-Line Diagrams Appendix G. Project Schedules Appendix H. Foster Wheeler Basis of Labor Appendix I. General Arrangement Drawings Appendix J. Conceptual Capital Cost Estimates Appendix K. Specification Summary Packages Appendix L. Master Procurement List Appendix M. Model Files Appendix N. Model Views Appendix O. SRP-Provided Data Appendix P. NPS Communications Appendix Q. Presentation for NPS Appendix R. Presentation for EPACP-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 CERTIFICATION FOR REPORT

FOR

SALT RIVER PROJECT

NAVAJO GENERATING STATION

SCR AND BAGHOUSE CAPTIAL COST ESTIMATE

I CERTIFY THAT THIS REPORT WAS PREPARED BY ME OR UNDER MY SUPERVISION AND THAT I

AM A REGISTERED PROFESSIONAL ENGINEER UNDER THE LAWS OF THE STATE OF ARIZONA.

Electronic copy of final document;

Sealed original is with Arvind A. Patel

Certificate No. 48573

REVISION: CERTIFIED BY DATEIS-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### SALT RIVER PROJECT
NAVAJO GENERATING STATION

SCR AND BAGHOUSE CAPITAL COST ESTIMATE

ISSUE SUMMARY PAGE

PURPOSE OF ISSUE DATE PAGES AFFECTED

REV. A, FOR COMMENT 04-16-2010 ALL

REV. B, FOR USE 06-04-2010 ALL

REV. C, FOR USE 08-06-2010 EXECUTIVE SUMMARY 9.1.1 9.1.10 TABLE 9-1 9.4 TABLE 9-2 9.5 TABLE 9-3 APPENDIX J – ALL APPENDIX P – NEW APPENDIX Q – NEW APPENDIX R – NEW REV. D, FOR USE 08-17-2010 EXECUTIVE SUMMARY 1.2 9.3.1ES-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## EXECUTIVE SUMMARY

The United States Environmental Protection Agency (EPA) is currently in the process of developing a Best Available Retrofit Technology (BART) proposal for the Navajo Generating Station (NGS). One of the five statutory factors that must be considered in arriving at a BART proposal is the cost of each control technology option. Salt River Project (SRP) retained Sargent & Lundy, L.L.C (S&L) to perform a detailed cost study that can be used in developing a BART proposal for NGS. Sargent & Lundy, L.L.C. prepared this report to present the estimated capital cost for the addition of SCRs or SCRs and baghouses on all three units at NGS.

This report builds on the high-level feasibility studies that were performed by S&L in 2007 through 2009 for a similar scope of work. The original feasibility studies provided predicted costs based on a level of difficulty of the installation at NGS compared to typi cal costs experienced in the industry for other SCR and polishing baghouse installations. This report provides more detailed conceptual designs and cost estimates for the work.

For this report, S&L developed general arrangements, estimated quantities of materials, solicited budgetary quotes, and developed detailed cost estimates, schedules, and cash flows. Estimated quantities of materials were generated from the developed general arrangements. Since NGS is a highly congested site resulting in significant construction challenges, S&L had subcontracted Foster Wheeler to provide estimated construction costs, including costs for heavy-lift cranes, based on the general arrangements and estimated quantities.

A total of nine cost estimates have been developed, three for each NGS unit consisting of; one estimate for SCR only (SCR Option), one estimate for SCR with dry sorbent injection (SCR with DSI Option), and one estimate for SCR plus baghouse (SCR and Baghouse Option). S&L and Foster Wheeler worked in conjunction to develop project schedules for the work. The schedule for the design and procurement work was developed by S&L while Foster Wheeler provided input to the construction portion.

NGS consists of three (3) 812-MW (gross) CE/Alstom boilers that are fueled by Western bituminous coal from Peabody’s Kayenta mine on the Black Mesa. Currently, each unit utilizes a hot-side electrostatic precipitator (HESP) for particulate c ontrol and a wet flue gas desulfurization system (FGD) for SO 2 control. The units are also being retrofitted with low-NO X burners (LNBs) to reduce NO X emissions. S&L was asked to evaluate the cost of installing SCRs on each unit with an option to add polishing baghouses. The SCRs would tie into the flue gas path downstream of the existing HESPs and discharge upstream of the existing air pre-heaters. The baghouses would tie into the flue gas path downstream of the existing air pre-heaters and disc harge upstream of the existing FGD systems. For the SCR and Baghouse Option, new ID booster fans would also be required.

Major equipment added would be two (2) SCR reactors per unit, a common anhydrous ammonia storage facility, unit-specific sorbent injection systems, and two (2) baghouse casings per unit. Unit 2 would incorporate a stacked baghouse design due to site space constraints. The work would include refurbishment of the existing ID fans for the SCR Option, or new ID booster fans for the SCR and Baghouse Option. All units would continue to di scharge through their existing unitized stacks.ES-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Several options were evaluated and estimated for the supply of power to the SCR and SCR plus baghouse system’s auxiliaries and ID fans. A new unit auxiliary transformer (UAT) would be installed to support new infrastructure for the SCR and Baghouse Option.

Site constraints present a number of constructi on challenges. Major concerns include the congestion and limited access available for installation of the potential new work on Unit 2, as well as the tie-in work for the SCRs on all three units. The tie-in work for the SCRs must be accomplished in the relatively congested area between the precipitators and the boilers, where access to large construction equipment is limited and at the same time must be accomplished in a relatively short duration during scheduled plant outages. For installation of the Unit 2 work, large cranes that would be set up outside of the immediate construction area, yet be capable of placing large loads into the construction area, would be necessary. Additional challenges include construction of the unique stacked baghouses in the congested Unit 2 area, and performing the majority of the Unit 2 installation work immediately adjacent to, under, and over the existing coal conveyors that provide coal to all three of the units at NGS.

In order to relocate existing plant utilities to make room for the SCRs and baghouses, a short duration outage (estimated at about one week) may be required early in the construction phase. Since this is not one of NGS’s regularly scheduled outages, lost generation costs associated with this outage have been included in the cost estimate. No costs have been added for lost generation during the eight week major outage since this is one of NGS’s regularly scheduled outages.

Engineering studies, project development, procurement, detailed engineering, design, construction, and startup schedules have been developed, assuming a target commercial operation of Unit 3 during a future three-year series of major outages. Separate schedules have been prepared for the SCR Option and SCR and Baghouse Option. Multiple lump sum construction contracting is assumed for the foundations, structural and mechanical construction, electrical / instrument & controls construction, testing and inspection, and final sitework. The schedul e is structured to utilize construction-quality bid documents for the procurement of ductwork, struct ural steel, and foundations. Separate construction contracts are assumed for each unit.

The conceptual cost estimates developed for the report are based on the developed general arrangements, preliminary equipment list, estimated quantities of materials, and budgetary quotes from vendors for major equipment. Unit costs of materials and the remaining equipment have been estimated based on S&L in-house data, vendor catalogs, industry publications such as Means and Richardson, and costs on other similar projects. The construction costs have been developed with input provided by Foster Wheeler. The estimated costs are based on the year 2010 price level, and include costs of equipment, materials, craft labor, indirect labor, overtime, per-diem, contractor’s general and administrative costs, contractor’s profit, A-E engineering, construction management, start-up, commissioning, owner’s costs, contingency, and allowance for funds used during construction (AFUDC). The owner’s costs include owner’s c onstruction management, spare parts, legal support, owner’s insurance, lost generation during short outages, ammonia unloading facility at railhead, and sales taxes. Future cost escalation is not included in the estimates. The contingencies included in the cost estimates are based on a risk analysis using Monte Carlo simulations to obtain a 95% confidence level of not exceeding the budget. The AFUDC is calculated based on 2.43% annual percentage rate. Preliminary cash flows have also been developed.ES-3 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 • Table ES-1 is a summary of the 2010 capital cost estimates for the SCR Only Option.

• Table ES-2 is a summary of the 2010 capital cost estimates for the SCR Only - With Dry Sorbent Injection Option.

• Table ES-3 is a summary of the 2007 capital cost estimates for the SCR Only Option.

• Table ES-4 is a summary of the 2010 capital cost estimates for the SCR and Baghouse Option.

• Table ES-5 is a summary of the 2007 capital cost estimates for the SCR and Baghouse Option.

The overall costs developed in this study are sim ilar to the costs developed in the 2007 through 2009 high level feasibility studies. Costs for the SCR Only Option decreased from the earlier studies since it has been determined that the existing ID fan moto rs and auxiliary power system have adequate capacity to support the new SCR systems. Typica lly, implementation of an SCR system would be expected to require new ID Fans and new transformers; however, these costs would not be incurred for the NGS SCRs. The fan and auxiliary power upgrades would be required for the SCR and Baghouse Option, thus, the reduced costs are not seen in the estimates for the SCR and Baghouse Option. The relative costs for the Unit 3 installations are higher in the current study than in the earlier studies because costs for common systems that support all three Units have been allocated to Unit 3. This study is considerably more detailed than the earlier high level feasibility studies.

The total annualized costs presented in the December 2008 BART Analysis have been updated to reflect the revised capital and annual O&M costs for the three different options. Table ES-6 presents the updated annualized costs.

Unit 1 Unit 2 Unit 3 & Common Total

SCR (Includes Sitework) $ 50,386,000 $ 63,860,000 $ 60,661,000 $ 174,907,000

Electrical and I&C $ 3,478,000 $ 3,888,000 $ 5,297,000 $ 12,663,000

Construction Equipment & Scaffolding $ 11,471,000 $ 18,934,000 $ 14,091,000 $ 44 ,496,000

Other Direct & Construction Indirect Costs $ 29,731,000 $ 41,879,000 $ 37,491,000 $ 109,101,000

Indirect Costs $ 38,481,000 $ 50,135,000 $ 46,699,000 $ 135,315,000

Contingency $ 15,224,000 $ 23,052,000 $ 18,559,000 $ 56,835,000

AFUDC $ 3,054,000 $ 4,060,000 $ 3,730,000 $ 10,844,000

Total Project Costs $ 151,825,000 $ 205,808,000 $ 186,528,000 $ 544,161,000

$/kw (812MW Gross) $187 $253 $230 $223 $/kw (750MW Net) $202 $274 $249 $242 Table ES-1 Summary of SCR Only Capital Cost EstimatesES-4 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Unit 1 Unit 2 Unit 3 & Common Total

SCR (Includes Sitework) $ 51,931,000 $ 65,479,000 $ 62,201,000 $ 179,611,000

Electrical and I&C $ 3,478,000 $ 3,883,000 $ 5,342,000 $ 12,703,000

Construction Equipment & Scaffolding $ 11,617,000 $ 19,117,000 $ 14,253,000 $ 44 ,987,000

Other Direct & Construction Indirect Costs $ 30,198,000 $ 42,442,000 $ 38,000,000 $ 110,640,000

Indirect Costs $ 39,066,000 $ 50,825,000 $ 47,298,000 $ 137,189,000

Contingency $ 15,537,000 $ 23,445,000 $ 18,882,000 $ 57,864,000

AFUDC $ 3,119,000 $ 4,133,000 $ 3,796,000 $ 11,048,000

Total Project Costs $ 154,946,000 $ 209,324,000 $ 189,772,000 $ 554,042,000

$/kw (812MW Gross) $191 $258 $234 $227 $/kw (750MW Net) $207 $279 $253 $246 Table ES-2 Summary of SCR Only - With Dry Sorbent Injection - Capital Cost Estimates

Unit 1 Unit 2 Unit 3 & Common Total
SCR Only $ 188,000,000 $ 254,000,000 $ 188,000,000 $ 630,000,000

$/kw (812MW Gross) $232 $313 $232 $259 $/kw (750MW Net) $251 $339 $251 $280 Table ES-3 Summary of 2007 Capital Cost Estimate - SCR Only (Including Outage Costs)ES-5 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Unit 1 Unit 2 Unit 3 & Common Total

SCR (Includes Sitework) $ 49,653,000 $ 63,370,000 $ 60,514,000 $ 173,537,000

Baghouse $ 71,095,000 $ 67,771,000 $ 52,948,000 $ 191,814,000

Electrical and I&C $ 14,977,000 $ 14,831,000 $ 18,437,000 $ 48,245,000

Construction Equipment & Scaffolding $ 29,345,000 $ 33,270,000 $ 26,577,000 $ 89 ,192,000

Other Direct & Construction Indirect Costs $ 78,797,000 $ 85,736,000 $ 70,100,000 $ 234,633,000

Indirect Costs $ 77,981,000 $ 86,030,000 $ 73,737,000 $ 237,748,000

Contingency $ 42,484,000 $ 51,247,000 $ 38,092,000 $ 131,823,000

AFUDC $ 7,852,000 $ 8,664,000 $ 7,464,000 $ 23,980,000

Total Project Costs $ 372,184,000 $ 410,919,000 $ 347,869,000 $ 1,130,972,000

$/kw (812MW Gross) $458 $506 $428 $464 $/kw (750MW Net) $496 $548 $464 $503 Table ES-4 Summary of SCR and Baghouse Capital Cost Estimates

Unit 1 Unit 2 Unit 3 & Common Total
SCR & Baghouse $ 288,000,000 $ 434,000,000 $ 288,000,000 $ 1,010,000,000

$/kw (812MW Gross) $355 $534 $355 $415 $/kw (750MW Net) $384 $579 $384 $449 Table ES-5 Summary of 2007 Capital Cost Estimate - SCR & Baghouse (Including Outage Costs)ES-6 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 SCR Option SCR with DSI Option SCR & Baghouse Option

Unit 1 Total Capital Cost $ 151,825,000 $ 154,946,000 $ 372,184,000 Annual Capital Cost (Total Capital Cost x CRF) $ 17,597,000 $ 17,958,000 $ 43,136,000
Annual O & M Cost $ 3,982,000 $ 4,257,000 $ 6,878,000 Total Annual Cost $ 21,579,000 $ 22,215,000 $ 50,014,000

Unit 2 Total Capital Cost $ 205,808,000 $ 209,324,000 $ 410,919,000 Annual Capital Cost (Total Capital Cost x CRF) $ 23,853,000 $ 24,261,000 $ 47,626,000
Annual O & M Cost $ 3,982,000 $ 4,257,000 $ 6,878,000 Total Annual Cost $ 27,835,000 $ 28,518,000 $ 54,504,000

Unit 3 Total Capital Cost $ 186,528,000 $ 189,772,000 $ 347,869,000 Annual Capital Cost (Total Capital Cost x CRF) $ 21,619,000 $ 21,995,000 $ 40,318,000
Annual O & M Cost $ 3,982,000 $ 4,257,000 $ 6,878,000 Total Annual Cost $ 25,601,000 $ 26,252,000 $ 47,196,000

Units 1,2,& 3 Total Capital Cost $ 544,161,000 $ 554,042,000 $ 1,130,972,000 Annual Capital Cost (Total Capital Cost x CRF) $ 63,069,000 $ 64,214,000 $ 131,080,000
Annual O & M Cost $ 11,946,000 $ 12,771,000 $ 20,634,000 Total Annual Cost $ 75,015,000 $ 76,985,000 $ 151,714,000 Capital Recovery Factor (CRF) = 0.1159 Based on an interest rate of 9.8% and amortization period of 20 years Table ES-6 Levelized Annual Costs

The results of this study addressed the input received from the National Park Service (NPS) and EPA Region 9. The NPS complemented the level of technical rigor that went into the cost engineering work and acknowledged the soundness of the overall study methodology. The NPS provided several observations regarding control levels and app licability of the EPA Pollution Control Cost Manual (PCCM) estimates. These comments and the responses are included in Appendix P. The PCCM was designed by EPA to be used on units 25MW to 600MW, and on “high dust” units that have only one reactor per combustion unit. NGS is larger than 600MW, would be a “low dust” application and would have two reactors per combustion unit. The PCCM cost model was not designed to be used on a unit similar to those found at NGS. But the NPS suggested that it might be helpful (while understanding the limitations of the PCCM) to calculate the cost using the PCCM so a relative comparison can be made between this project and other projects previous ly considered by EPA. When using the PCCM and adjusting the cost developed by a composite BLS price index, the PCCM predicts that the cost of an SCR on NGS Unit 1 in 2010 would be $47,844,624 or $64/kW (see Appendix P). Recent Surveys (data provided by NPS and public sources) of actual SCR in stallations show that costs for SCRs vary fromES-7 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 $100/kW to $300/kW. The cost developed in this study falls inside the reported range at $228/kW while the cost predicted by using the PCCM is outside the range. The NPS also participated in the July 20, 2010 discussions with EPA. An NPS representative raised several questions that have been addressed in this report. These responses as well as responses to questions made by EPA in that meeting are also found in Appendix P.1-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 1. GENERAL PLANT DESCRIPTION

1.1 DESCRIPTION OF EXISTING PLANT

NGS is located on the Navajo Indian Reservation near Page, Arizona. It consists of three (3) 812-MW (gross) coal-fired units, which entered service in 1974, 1975, and 1976, respectively. NGS serves electric customers throughout t he Southwest, and also supplies energy to pump water through the Central Arizona Project.

The fuel for NGS is provided by Peabody West ern Coal Company’s Kayenta Mine located approximately 50 miles to the east. The coal is deliv ered to the site via a dedicated rail from the coal mine to the plant. Cooling water for the station is supplied by nearby Lake Powell.

Each of the three (3) existing units is equipped with stacked hot-side electrostatic precipitators (HESPs) for particulate control and FGD scrubbers for SO 2 reduction. As part of a separate ongoing project, the units are also being retrofitted with low-NO X burners (LNBs) to reduce NO X emissions.



### 1.2 OVERVIEW OF CONCEPTUAL AIR QUALITY CONTROL SYSTEMS (AQCS)

To further reduce NO X emissions, selective catalytic reac tion (SCR) systems, proven control technology for reducing NO X , would be required.

1.2.1 SCR Option

As part of a Best Available Retrofit Technology (BART) assessment for NGS, SCR systems are being evaluated. An SCR system requires a cata lyst, which uses anhydrous ammonia injection to react with NO X present in the flue gas. This is a proven control technology for reducing NO X
. In order to limit the increase in sulfur trioxide/ sulfuric acid (SO3/H2SO4) emissions, catalyst with ultra-low SO 2 to SO 3 oxidation (< @ 0-5% across reactor) would be procured for use in the SCR.

In the event sorbent injection is required for mitigating SO 3 emissions associated with SCR, a further study would have to be conducted to determine if the existing FGD system can remove the additional particulates that would be formed.

1.2.2 SCR and Baghouse Option

Under the SCR and Baghouse Option, the existing HESPs would remain in service and new polishing baghouses would be installed downstream of the air preheater and upstream of the existing wet FGD systems. This type of system consists of fabric bags, which hang from a tubesheet, which then collect particulate on the surface of the bag. At periodic intervals, compressed air is piped through the bags, inflating them to remove the captured material off the bag to be collected in hoppers below each compartment. This reduces the amount of particulate emissions and is a proven emissions control technology.1-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 To reduce sulfur trioxide (SO 3 ) emissions, S&L evaluated the cost of dry sorbent injection (DSI) systems on each unit. This type of system consists of sorbent storage, sorbent feed, and sorbent injection systems, which use either a calcium- or sodium-based sorbent to react with SO 3 present in the flue gas. This offers significant reduction in the amount of sulfuric acid (SO 3 /H 2 SO 4 ) emissions.2-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 2. DESIGN BASIS

2.1 GENERAL

Site-specific design basis and criteria documents were developed for mechanical, electrical, I&C, and civil/structural work. The design basis document used in the development of the cost estimate is provided in Appendix A.

A summary of key design parameters for the SCR catalyst and ancillary equipment sizing has been provided in Table 2-1 below. The values in this table represent measured data, estimated concentrations based on engineering experience and judgment, estimated ammonia feed rates based on a specified slip, and the outlet NOx design point for maximum and minimum load. Table 2-1. SCR Design Criteria Summary SCR Design Criteria (Values typical for all Units) Units Maximum Load Minimum Load

a. Load MW 812 403
b. Heat Input to Boiler MBtu/hr 7,350 3,650

c. Flue Gas Mass Flow Rate lb/hr 7,308,000 3,629,000
d. Flue Gas Vol. Flow Rate acfm 4,179,000 1,813,800

e. Pressure at SCR Inlet in. w.g. -11.25 -11.25
f. Flue Gas Temperature at SCR Inlet ° F 670 500 g. Economizer Bypass -- Yes* h. Inlet NO x lb/MBtu 0.24 0.17
i. Outlet NOx lb/MBtu 0.05 0.05
k. SO 2 Concentration at SCR Inlet ppmvd 621 602
l. SO 3 Concentration at SCR Inlet ppmvd 3.74 3.63 m. Ammonia Injection Required lb/hr 550 173 n. Design Ammonia Slip ppmvd @ 3% O 2 2 2

o. Estimated Flue Gas Composition to SCR N 2 vol% 71.45 71.59 O 2 vol% 2.87 3.35
H 2 O vol% 11.81 11.58
CO 2 vol% 13.79 13.40 SO 2 ppmv 547 532 SO 3 ppmv 3.30 3.21 HCl ppmv 0 0 HF ppmv 0 0 * An Economizer bypass will be required to maintain mi nimum flue gas temperature of 580°F at the inlet of the SCR.2-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Table 2-2. SCR Opti on Design Emissions

Emission lb/mmBtu

NO X Current Permit Current Operation SCR Design 0.24 (1)

0.20 to 0.22 (1)

0.05
Notes: (1) Based on LNB in operations

Table 2-3. SCR and Baghouse Option Design Emissions

Emission lb/mmBtu

NO X Current Permit Current Operation SCR Design 0.24 (1)

0.20 to 0.22 (1)

0.05

Particulate matter: Total PM 10 Current Emissions Proposed Emissions 0.06
0.015 (2)

Notes: (1) Based on LNB in operations (2) Based on polishing fabric filter.

2.1.1 NO x Control

NO X emissions would be controlled using SCR technology. The SCR system would be designed under ideal operating conditions to achieve an actual NO X emission rate of approximately 0.05 lb/mmBtu to ensure compliance with an anticipated NO X limit of 0.07-0.08 lb/mmBtu on a 30-day rolling average. Margin is provided between the design target and the anticipated NOx limit to allow for normal operating fluctuations associated with minor equipment upsets, fuel characteristics impacting NO X generation, and SCR process delays due to load changes.

2.1.2 Particulate Control

Particulate emissions would be controlled on all three NGS units using the existing HESPs. The HESP systems have been designed to achieve an actual PM emission rate to ensure compliance with an anticipated PM limit of 0.05 lb/mmBtu on a 30-day rolling average. Margin is provided between the design target and the anticipated limit to allow for normal operating fluctuations associated with minor equipment upsets, fuel characteristics, and load changes.

2.1.3 Sulfuric Acid Mist Control

As a result of the potential installation of the new SCRs on all three NGS units to reduce NO X emissions below the projected permit limit, the unc ontrolled sulfuric acid mist emissions would be expected to increase due to SO 2 oxidation across the catalyst. In an effort to reduce the sulfuric acid mist emissions, the following measures are being considered:2-3 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 1. Design the SCR for ultra-low SO 2 to SO 3 conversion catalyst which will limit SO 2 oxidation to below 0.5% across the reactor. This is expected to increase the particulate loading entering the wet FGD system. The wet FGD system is expected to capture some portion of this particulate matter, which may be significant enough to prevent increasing the plant’s particulate emissions above a level that would affect the plant permit. 2. If ultra-low conversion catalyst alone is not capable of preventing a significant increase in plant emissions of particulate matter, sorbent would be injected upstream of the existing wet FGD systems to react with the sulfuric acid to form sodium- or calcium sulfate. The WFGD system would again be required to capture the generated solids to prevent a significant increase in particulate emissions. 3. In the event that sorbent injection upstream of the WFGD system is not sufficient enough to prevent a significant increase in particulate emissions, pulse jet fabric filters would be installed upstream of the existing WFGD systems. Sorbent would be then injected and the resultant particulate captured in the baghouses.



### 2.2 METEOROLOGICAL CRITERIA

Site-specific meteorological criteria were in cluded in the design basis and are provided in Appendix C.



### 2.3 INDUSTRY CODES AND STANDARDS

Systems, structures, and equipment would meet the latest codes and standards within the design basis in Appendix A.



### 2.4 SUPPORTING DOCUMENTS

Existing plant documentation, drawings, and oper ational data were utilized. These documents are listed in Appendix A. Select documents are included in Appendix O for future reference.3-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 3. PLANT MECHANICAL SYSTEMS AND EQUIPMENT

3.1 SERVICE WATER SYSTEM

Based on S&L’s experience with SCR and baghouse re trofit projects, the ancillary systems for the SCR and baghouse have minimal service water demands. It is assumed that the existing plant service water system has adequate pressure and flow margin to meet the water requirements of the SCR Option or SCR and Baghouse Option.

3.1.1 SCR Option

For the SCR Option, service water would be utilized for wash down hose stations in the SCR area, as well as in the ammonia unloading area.

3.1.2 SCR and Baghouse Option

In addition to the service water requirements for the SCR Option, the SCR and Baghouse Option requires service water at wash down stations within the baghouse area and ID booster fan area. Service water would also serve as the cooling medium for the baghouse pulse-jet compressors; approximately 150 gallons per minute (gpm) per unit would be required for compressed-air cooling. The cooling water would be discharged to a local collection sump and admitted to the FGD process via the mist eliminator wash water tank.



### 3.2 POTABLE WATER SYSTEM

This cost estimate assumes that the existing plant potable water system has adequate pressure and flow margin to support additional users for the SCR Option or SCR and Baghouse Option.

3.2.1 SCR Option

The expected additional potable water users for the SCR include eyewash/emergency shower for the anhydrous ammonia storage area.

3.2.2 SCR and Baghouse Option

In addition to the potable water users for the SCR Option, the SCR and Baghouse Option requires potable water for eyewash/ emergency shower for the sorbent unloading area, as well as the waste silo area.

Each of the eyewash stations and emer gency showers stated above would require approximately 5-20 gpm. The new potable water distribution header for ancillaries would tie into the existing potable water header and be supplied by a new 2-inch, heat-traced, stainless steel header.3-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 3.3 FIRE PROTECTION SYSTEMS

Fire protection for new emissions control equipm ent would be provided by the existing NGS fire protection system; this includes fire pumps, yard piping, and hydrants. It is assumed the existing fire protection system has sufficient capacity to meet these new demands.

3.3.1 SCR Option

Fire protection for the SCR and auxiliary equipment would require fire hydrants located within 50 feet of the SCR structure. The fire protection header would also be extended to the new ammonia unloading area and supply quench water for ammonia leak protection as well as an additional hydrant for fire protection in the area.

3.3.2 SCR and Baghouse Option

Fire protection for the baghouse and auxiliary equipment would require fire hydrants located within 50 feet of the baghouse structure. The baghouse would be designed with polyphenylene sulfide (PPS) fabric bags to minimize fire potential. PPS fabric bags are neither flammable nor combustible. A fire water standpipe would provide water to the penthouse area for use during outages when flammable materials may be present.

The existing fire protection system would also be extended to the new unit auxiliary transformers (UATs) deluge system.

Below-grade fire protection piping would be either 8-inch or 10-inch SDR 9 HDPE piping and would be buried below frost depth per National Fire Protection Association (NFPA) codes. Above-ground fire protection piping would be carbon steel.



### 3.4 PLANT AND INSTRUMENT AIR SYSTEM

3.4.1 SCR Option

This cost estimate assumes the existing plan t compressed air systems have adequate capacity, flow, and pressure margin, to meet the demand of new users for the SCR addition. However, air receivers would be added to support the sonic horns used to clean the catalyst.

3.4.2 SCR and Baghouse Option

The addition of the baghouse adds a large air user to the plant. To meet the air consumption requirements for the pulse-jet cleaning system of the baghouse, 2 x 100%, oil-free, centrifugal compressors would be added per unit. These compressors would also provide compressed air to all new intermittent-user (valves, instruments, tools, etc.); therefore, no additional compressed-air load would be added to the existing plant compressed air systems. All air would be dried to -40°F dew point by implementi ng 2 x 100%, heated blower, purge-type regenerative desiccant dryers.

All instrument air piping would be stainless steel. All service air piping would be carbon steel.3-3 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Refer to sketches MSK-1002-01, MSK-1002-02, MSK-1002-03, MSK-2002-01, MSK-2002-02, MSK-2002-03, MSK-3002-01, MSK-3002-02 and MSK-3002-03 in Appendix D for conceptual design.



### 3.5 FLUE GAS SYSTEM

3.5.1 General Ductwork

For the purposes of the capital cost estimate, all existing ductwork is considered to be capable of safely withstanding its original design conditions. No degradation of the ductwork from corrosion or other deleterious effects is considered to be present in the system, and no resources are proposed for a condition assessment of the existing ductwork or for reinforcement of the ductwork due to loss of material from corrosion or similar effects.

All new ductwork would be sized to achieve a fl ue gas velocity of approximately 60 feet per second (fps). In areas where new ductwork would be restricted in size due to space constraints placed by existing items, higher velocities w ould be experienced. Thicker duct plate would be used to account for erosion in areas where the velocity exceeds 90 fps.

3.5.2 SCR Option Ductwork

The new ductwork to and from the SCR systems woul d exit the existing system downstream of the HESPs and would tie back in upstream of the air heaters. These tie-ins would occur in the available space between the existing boiler bui lding and the HESPs. For Units 1 and 3, common ducts would be routed to and from SCR systems that are located side-by-side to one side of the unit, to the north for Unit 1, and to the south for Unit 3. For Unit 2, the SCR systems would be separated from each other because of space constraints in this congested area, and separate ductwork would run on the north and the south si des of the HESP to and from the separate SCR systems placed to the north and south of the Unit 2 chimney.

Revised internal pressures in the existing flue gas ductwork that would result from adding the new SCR systems into the system and modi fying the existing ID Fans would require reinforcement of the existing ductwork downstream of the added SCR systems. Sufficient controls on the existing ID Fans would ensure that there are no changes to internal pressures in the existing ductwork upstream of the SCR systems, back to and including the boiler; therefore, no reinforcement would be needed for this portion of the ductwork because of revised pressures.

3.5.3 SCR and Baghouse Option Ductwork

The new ductwork to and from the baghouses would exit from and return into the existing ductwork in the area of the abandoned chimneys that runs from the existing ID Fans to the FGD area. For both Units 1 and 3, common ducts would be routed to the two baghouses that would be located side-by-side to one side of the unit, to the north for Unit 1, and to the south for Unit 3, and then on to two ID Booster Fans, also placed side-by-side, before returning to the existing ductwork that leads into the FGD system. For Unit 2 the baghouses would be stacked due to the extreme congestion in the area and the new ID Booster Fans would be separated, but the3-4 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 ductwork routing, though complicated by the tight arrangement, would be essentially the same as on the other two units.

Refer to sketches MSK-1005-01, MSK-1005- 02, MSK-2005-01, MSK-2005-02, MSK-3005-01 and MSK-3005-02 in Appendix D for conceptual design.

3.5.4 SCR Option Mechanical

Currently, the NGS flue gas path contains four (4) centrifugal ID fans arranged in parallel. Theoriginal maximum continuous rating (MCR) of these fans is 675,000 acfm at 33.8 inwg. Postscrubber installation, NGS performed an As-Tested Condition for the ID fans and the results identified the new duty point as 895,103 acfm at 31.41 inwg., with a motor operating point of 6,143 horsepower (hp).

Based on preliminary calculations, the existing ID fans would require modifications to support installation of the new SCR systems. The existing rotating element would be replaced with a new rotor assembly (impeller, shaft, and bearings). The new rotating element would be tipped to meet the additional pressure drop requirements of the SCR. Typically, tipping a centrifugal ID fan would result in the following performance increases: 7.5% flow, 15% pressure, and 27.5% brake horsepower. The increased flow and pressure requirements that would be seen by the addition of an SCR are within the 7.5% and 15% increases. The larger horsepower requirement is acceptable for the existing fan motor. See Section 4.0 for additional information on the electrical systems.

The existing air heater would need to be evaluated to determine if it would properly perform at the modified ID fan duty point or need other modifications to address ammonium bisulfate fouling or acid condensation associated with the SCR. The cost estimate includes allowances to perform an air heater evaluation and structural reinforcement. These allowances would be refined upon detailed engineering and evaluation by the original air heater manufacturer.

3.5.5 Air Heater Evaluation

3.5.5.1 Ammonium Bisulfate Formation

The application of SCR technology to coal fired power plants creates a potential problem with the deposition of ammonia-sulfur salts in the air preheater. The vanadium/titanium-based catalyst will oxidize a portion of the sulfur dioxide in the flue gas to sulfur trioxide. Under certain temperature and concentration conditions, the sulfur trioxide will react with ammonia slip from the SCR reactor to form ammonium bisulfate (ABS) which will tend to deposit in the air preheater. If favorable conditions for this reaction persist and ammonia concentrations reach higher than the designed value of 2 ppmvd, frequent washings of the air preheater may be required.

The installation of an SCR system will result in a small amount of ammonia gas and an increase in sulfur trioxide gas over the current level entering the air preheaters. Currently, sulfur trioxide (SO 3 ) calculations and test data performed for these Units show that the SO 3 is approximately 4 ppmvd at 3% O 2 entering the APH. The catalyst for the new SCR systems would be specified3-5 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 with a maximum SO 2 conversion of 0.50% for the entire system. This results in an SO 3 concentration at the APH of approximately 6 ppmvd at 3% O 2 . Under certain conditions, SO 3 and ammonia will react to form ammonium bisulfate (ABS) according to the following reaction:

NH 3 + SO 3 + H 2 O = NH 4 HSO 4 ABS will condense from the gas stream and form a sticky deposit on the heat transfer surface of the air heater at a temperature of 380 – 450 ° F. Fly ash particles will tend to stick to the ABS resulting in the gradual pluggage of the APH. Depending on the degree of formation, this could result in an increase in APH pressure drop (impacting ID fan capacity) as well as a loss in thermal efficiency for the plant.

ABS is also corrosive (acidic in nature) and will corrode the mild steel or low alloy steel surfaces of the APH. The rough surface of corroded material further enhances the deposition of ammonium bisulfate and accelerates the plugging mechanism.

3.5.5.2 Ammonium Bisulfate Impact on Navajo SCR Systems
Combustion of the design fuel and SCR installation will result in the following gas conditions leaving the economizer and entering the APH.

Economizer Outlet SCR Outlet/APH Inlet Temperature at Full Load (°F) 670 673 SO 3 Concentration (ppmvd @ 3% O2) 3.72 6.18

The oxidation of SO 2 to SO 3 is controlled by the catalyst formulation; the catalyst must be formulated to restrict oxidation of SO 2 to control SO 3 production which could accelerate ABS formation and/or create a visible sulfuric acid plume. A design of 2 ppmvd (@ 3% O2) ammonia slip at the end of catalyst life and an oxidation rate of 0.50% across the reactor was chosen to minimize SO 3 formation to prevent any substantial incr ease in sulfuric acid emissions. Low ammonia slip also minimizes the nitrogen c ontent in scrubber water blowdown. If SO 3 is limited to less than 7 ppm, the possibility of having blue plume is eliminated.

The concentration of ammonia and SO 3 will vary across the cross sectional area of the reactor exit. If areas with higher concentrations of NH 3 coincide with areas of high SO 3 concentrations then ABS may form in localized areas of the air preheater. This phenomenon must be taken into consideration when selecting APH protection such as enameled coatings. A typical formation diagram for ammonium bisulfate is shown in Figure 1.3-6 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 The ABS dew point while burning bituminous fuel will be in the temperature range of 590 °F to 615 ° F. The melting point of this compound is 300 ° F and the boiling point is 914 ° F. Once this compound is formed, it will be in liquid phase above 300 ° F and the solid phase below 300 ° F. Therefore, all metal surfaces of the APH from 300 ° F to 615 ° F will be subjected to ammonium bisulfate deposition.

The following conclusions can be drawn from Figure 1:

• The formation diagram for ammonium bisulfate suggests the potential formation of ABS in the air preheater.

• The likelihood of ammonium bisulfate formation is higher at the end of catalyst life when firing the higher sulfur fuels, when the ammonia slip would be close to 2 ppm in conjunction with approximately 6 ppmvd SO 3 .3-7 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 The following design elements for the Navajo SCR system are important to reduce the likelihood that ammonia bisulfate formation will be a significant problem:

• Ensuring proper catalyst design, including 2 ppm ammonia slip and maximum 0.50% oxidation of SO 2 to SO 3 across the SCR reactor.

• Ensuring NH 3 /NOx distribution requirements are demonstrated in the CFD and physical flow modeling to avoid large areas of high ammonia slip.

3.5.5.3 Air Heater Basket Recommendation

Based on normal catalyst performance, NH3 slip should range from a negligible value during initial operation to less than 2 ppm towards the end of the catalyst life. After the SCR installation, SO 3 levels as high as 6 ppmvd at 3% O 2 are possible. SRP currently operates on a three year outage cycle which will require t he SCR systems to operate at close to 100% reliability. Significant ABS formation and air heater plugging is not expected due to the low SO 3 content in the flue gas and it is not likely that a change in air heater basket material would be required.

3.5.6 SCR and Baghouse Option Mechanical

For existing ID fan configuration and performance data, see subsection above.

Based on preliminary calculations, new ID booster fans would be required to support the installation of the SCR and baghouse. The existing four (4) 25% (per unit) ID fans would be used (without modifications) and two (2) new 50% axial ID booster fans (per unit) would be added between the baghouse and wet scrubber inlet. The existing ID fan would operate at a decreased pressure rise in order to achieve a pre ssure of -1 in. W.C. at the fan discharge. It is an industry standard to maintain baghouses under negative pressure to avoid flue gas leakage.

ID fan isolation would be accomplished by doubl e-louver-type and guillotine isolation dampers at the ID fan inlet and outlet, respectively.

Refer to the design basis document (Appendix A) for assumptions and inputs as well as sketches MSK-1005-01 and MSK-1005-02 (Appendix D).



### 3.6 SORBENT INJECTION SYSTEM

3.6.1 SCR Option

Sorbent injection for SO 3 control would utilize hydrated lime for the SCR Option. The hydrated lime would be delivered to one of three silos lo cated near each unit’s injection point. The sorbent would be offloaded from the truck via onboard blowers, into a seven-day storage silo. The hydrated lime would then be transferred from the storage silo to the ductwork injection point via 2 x 100% blowers provided at each sorbent storage silo. Sorbent can be injected either upstream or downstream of the air preheater; fo r Navajo, sorbent will be injected upstream of the air preheater. Carbon steel pipe would be used to transfer the hydrated lime to the ductwork3-8 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 and carbon steel injection lances would be utilized to get satisfactory distribution within the duct. The sorbent would be collected and removed from the flue gas stream in the existing wet FGD.

3.6.2 SCR and Baghouse Option

Sorbent injection for SO 3 control would utilize a sodium-based sorbent, such as trona, for the SCR and Baghouse Option. The trona would be delivered to one of three silos located near each unit’s injection point. The sorbent would be offloaded from the truck via onboard blowers, into a seven day storage silo. The trona would then be transferred from the storage silo to the ductwork injection point via 2 x 100% blowers provided at each sorbent storage silo. Sorbent can be injected either upstream or downstream of the air preheater; for Navajo, sorbent will be injected upstream of the air preheater. Carbon steel pipe would be used to transfer the trona to the ductwork and carbon steel injection lances would be utilized to get satisfactory distribution within the duct. Further evaluation is required to determine if the sorbent can be collected in the existing wet FGD. If the FGD will not adequately remove the sorbent then the SCR plus baghouse option would have to be used.

Refer to sketches MSK-1004-01, MSK-2004-01 and MSK-3004-01 in Appendix D for conceptual design.



### 3.7 SCR

3.7.1 SCR Reactors

Preliminary calculations indicate that 2 x 50% SCR reactors would be required for each unit. Each SCR reactor would be of a 4-catalyst layer design, with only 2 layers being initially loaded. The SCR would be designed to operate with ultra-low SO 2 -to-SO 3 conversion catalyst, using sonic horns to keep the catalyst levels clean. Additionally, vacuum cleaning lines would be installed with each reactor. These lines would be routed to a terminal point where a vacuum truck could be hooked up to assist in cleaning a reactor during an outage. Each SCR reactor would have an economizer inlet flue-gas side bypass, to ensure that the flue gas temperature is above 580°F at the reactor inlet. No reactor by pass would be provided. The economizer inlet flue-gas side bypass would be designed with double-louver-type isolation dampers and seal air. Feedwater recirculation may also be used to increase the flue gas temperature above 580 oF. During detailed design, both options would be evaluated, and the most cost effective option would be selected. The cost of a feedwater recirculation modification is typically less than an economizer bypass, which is the basis for the estimate,

Anhydrous ammonia has been chosen as the reagent for this study. Additional studies will be needed to better understand the costs and the risks associated with the options of anhydrous ammonia, aqueous ammonia, and urea. The anhydrous ammonia is delivered in liquid form, and then vaporized to form gaseous ammonia. Approx imately 550 lbs/hr of gaseous ammonia would be required per unit (275 lbs/hr per reactor).

3.7.2 Anhydrous Ammonia Delivery and Transfer

The delivery and transfer of anhydrous ammonia is the same both for the SCR Option and the SCR and Baghouse Option.3-9 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Anhydrous ammonia would be delivered to the si te via truck to a common ammonia unloading area located to the south of Unit 3. Anhydrous ammonia is a liquid, and would be unloaded via onboard truck pumps into one of three (3) bullet-type storage tanks. Each storage tank would be sized for 14 days of continuous operation at full load for one unit.

Each tank would have one dedicated pump to transfer the liquid anhydrous ammonia from the common storage area to each unit. In addition, one backup pump would be cross-tied to each tank to provide redundancy for each unit. The 4 x 33% pump arrangement maximizes operator turndown flexibility. The anhydrous ammonia would be transferred to each unit via special double-walled pipe utilizing leak detection cable located aboveground on a pipe rack. The interior pipe would be stainless steel and wo uld be the primary carrier for the anhydrous ammonia. A larger-diameter carbon steel pipe is utilized on the exterior to keep leaks contained.

3.7.3 Anhydrous Ammonia Vaporization and Injection

The vaporization and injection of anhydrous ammonia is the same both for the SCR Option and the SCR and Baghouse Option.

The anhydrous ammonia is pumped to the vaporizer sk id at each reactor. Each vaporizer skid consists of two vaporizers with each skid requiring 1,500 lbs/hr of low pressure steam, provided from the corresponding unit’s low-pressure steam system.

The gaseous ammonia leaves the vaporizer and mixes with dilution air for final reactor injection. Each vaporizer skid includes its own dilution ai r blower skid, with 2 x 100% blowers on each skid. The dilution air is heated with steam to match the temperature of the gaseous ammonia, and then blown to a static mixer, where it is mixed with the vaporized ammonia. This mixture (5% ammonia and 95% air) is then blown to the ammonia injection grid at one of the SCR reactors.

3.7.4 Low-Pressure Steam for Vaporizer

Low-pressure steam required for the vaporizer is the same both for the SCR Option and the SCR and Baghouse Option.

The low-pressure steam required for each vaporiz er would be provided from the corresponding unit’s low-pressure steam system. Once the steam has been used to vaporize the ammonia, it would be discharged to a local condensate storage tank. The condensate storage tank would discharge to a collection sump and the contents pumped to the mist eliminator wash water tank for reuse.

Refer to sketches MSK-1003-01, MSK-2003-01, MSK-3003-01 and MSK-3003-2 in Appendix D for conceptual design.3-10 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 3.8 PULSE-JET FABRIC FILTER (BAGHOUSE)

3.8.1 Baghouse

A baghouse system would be installed downstream of the existing ID fans and upstream of the new ID booster fans on all three units. Flue gas enters on the bottom half of the baghouse through an inlet plenum system. The gas rises through the baghouse and the particulates, generated by the reaction between the airborne SO 3 and injection sorbent, are collected on the outside of the filter bag. The gross air-to-cloth ratio would be designed to be 6:1. The cleaned flue gas discharges into a common outlet plenum and exits the baghouse casing through the upper half of the baghouse, on the same side as the inlet.

The baghouse system would consist of two casings, with each casing equipped with eight compartments. Each compartment contains a num ber of PPS filter bags (such that the air-tocloth ratio is 6:1) and can be isolated by the use of and inlet and outlet damper. The bags are cleaned by the use of 2 x 100% air compressors (with 2 x 100% dryers and 2 x 100% receivers), which are common to both casings.

The pulse-jet cleaning cycle is activated when the pressure drop across a casing is higher than the predetermined set point. The pulse-jet cleaning cycle requires compressed air to be sent sequentially into rows of cleaning headers, located just above the tops of the filter bags. As the compressed air is blown through a bag, the solids on the outside of the filter bag are released. These solids are then collected in hoppers located directly below the bags in each compartment. A dust detector is installed within each compartment to detect an increase in particulate emissions due to a damaged filter bag. Damaged filter bags can be replaced while the baghouse is on line by isolating the necessary compartment by closing the inlet and outlet dampers.

Each baghouse system would be equipped with an in ternal bypass for emergency situations where the flue gas temperature rises above the maximum bag temperature, which in this case (PPS bags), is 375oF. In this event, a poppet damper system connecting the inlet and outlet ductwork would fail open, opening up a path between the inlet and outlet plenum. Simultaneously, the inlet and outlet isolation dampers to each compartment would fail closed. This combination would protect the bags from the hot flue gas, while also providing an open gas path through the baghouse.

3.8.2 Waste Collection and Disposal System

For each unit, the baghouse waste would be transported from the individual compartment hoppers to a storage silo. The solid waste would be emptied from the hoppers via vibrators and discharged into a pipeline collection system that runs underneath each of the hoppers.

The solid waste would be transported in these lines via pneumatic blowers. Due to the physical arrangement, Unit 1 would require 2 x 100% blowers, while Units 2 and 3 would utilize a 3 x 50% setup (per unit). The waste storage silos would be sized for a 7-day storage capacity and would utilize 2x100% blowers to provide air to the fluidizing trays on the silo floor. The waste material would be removed from the silo and mixed with water using pin/paddle mixers, discharged into a truck and disposed into a plant landfill.3-11 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Refer to sketches MSK-1006-01, MSK-2006-01 and MSK-3006-01 in Appendix D for conceptual design.4-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 4. PLANT ELECTRICAL SYSTEMS AND EQUIPMENT

4.1 CODES AND STANDARDS

Electrical equipment and systems provided w ould be supplied by qualified and experienced manufacturers. Electrical equipment and system s would be of proven design and successfully used on power plant projects. The design and specifications would be in accordance with applicable regulations and applicable local codes and ordinances. Electrical equipment would meet the latest codes and standards.

Design practices at the existing plant would be utilized as deemed appropriate.



### 4.2 ELECTRICAL POWER SUPPLY SYSTEMS

The methods for powering each of the options are discussed below:

4.2.1 SCR Only Option (Each of Units 1, 2, and 3)

• The one-line diagrams for all three units and for the common facility are represented on drawing ESK-1000.

• Utilize existing ID fan motors.

• Two (2) unit station transformers (USTs) per unit fed from existing 4.16-kV switchgear.

• 480-V switchgears and motor control centers (MCCs) per unit.

• Common loads for the anhydrous ammonia system fed from existing 480-V buses LSPA/LSPB.

4.2.2 SCR and Baghouse Option (Each of Units 1, 2 and 3)

• The one-line diagrams for all three units and for the common facility are represented on drawings ESK-1001 SHT. 1, 2 and 3.

• One (1) three-winding unit auxiliary transformer (UAT) per unit.

• Two (2) 13.8-kV switchgears per unit.

• Two (2) 13.8-kV common switchgears for startup and shutdown.

• Two (2) 4.16-kV switchgear extensions per unit.

• Two (2) USTs per unit fed from exte nsion of existing 4.16-kV switchgear.

• 480-V switchgear and MCCs per unit.



### 4.3 BASIC ELECTRICAL SYSTEM

4.3.1 SCR Option

The electrical auxiliary power system would be designed to utilize the existing sources where applicable. The ID fan motors for each unit have spare capacity and therefore would be reused in conjunction with a retrofitted fan. New 4.16/0.48-kV USTs would be4-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 fed from the existing FGD 4.16-kV switchgear located in the FGD pump house of each unit. These transformers would provide the auxiliary power to 480-V switchgear and MCCs required for the SCR system loads.

The ammonia delivery system associated with the installation of the SCRs for each of the three units would be located at the south end of the power plant. The ammonia delivery system would require new 480-V MCCs. The MCCs would be powered from the existing switchgears LSPA and LSPB located in the limestone preparation enclosure.

Refer to drawings ESK-1000 SHT. 1 in Appendix F for the one-line diagrams for all three units.

4.3.2 SCR and Baghouse Option

New ID booster fans estimated to be 10,000 hp would be required for each unit to overcome the pressure drop through the new baghouse. The new booster fans cannot be supported from the existing UATs. It is therefore necessary to add one (1) new UAT and two (2) 13.8-kV switchgears for each unit to distribute power to the new ID booster fans.

Two (2) additional common switchgears would be added for unit startup and shutdown, and would be located in a common power distribution center (PDC) enclosure. The new common 13.8-kV switchgears would be powered from the existing station service 13.8- kV buses SSA and SSB.

An extension of the 4.16-kV switchgear bus would be required to provide the required quantity of feeders for the new auxiliary air compressor and 4.16/.48-kV UST.

The 480-V system loads would be fed from a pair of new 4.16-kV to 480-V transformers for each unit. The transformers would feed loads associated with the baghouse, SCR, and the ID booster fans.

Refer to drawings ESK-1001 SHT. 1, SHT. 2, and SHT. 3 in Appendix F.



### 4.4 AUXILIARY POWER SYSTEM PERFORMANCE

4.4.1 SCR Option

The auxiliary power system for the SCR Option si mply consists of addition of 4.16-kV to 480-V transformers tied to the existing plant auxiliary system and, hence, does not require extensive study. The 480-V transformer s would be selected to perform similarly to the existing 480-V system at the plant.

The capacity of each 480-V UST would be such that it would carry the entire load connected to the switchgear lineup with the other transformer out of service.4-3 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 4.4.2 SCR and Baghouse Option

The auxiliary power system for the SCR and Baghouse Option would be designed to provide an adequate and reliable power supply to the plant's electrical auxiliary loads. The system would be designed to handle auxiliary load requirements under all plant operating modes and under the contingency of the loss of any of its UATs.

The auxiliary power system would consist of the main components and subsystems, such as UATs and USTs, medium- and low-voltage distribution systems, motors, and other electrical loads.

The design of the auxiliary power system would be based on results of an Auxiliary Power System Study. The results of the study would determine the new UAT MVA ratings, auxiliary power system voltages, aux iliary transformer impedances, the short circuit rating at each voltage to achieve acceptable steady state voltage regulation at each power system bus, and to achieve acceptable voltage regulation during motor starting. The study would consider reasonable contingency operating conditions such as a single transformer out of service. The study would also consider full-load operation as well as startup and shutdown of the unit.

The auxiliary power system study would use the following criteria to establish acceptable performance:

• The total capacity of the UAT would be sufficient to supply both ID booster fans for the SCR and Baghouse Option. The remaining auxiliary loads would be fed from the existing UATs and the existing plant auxiliary system. The existing auxiliary system would be checked for adequate performance.

• The capacity of each 480-V UST would be such that it would carry the entire load connected to the switchgear lineup with the other transformer out of service.

• The momentary and interrupting short circuit duty on the auxiliary system circuit breakers would be within the corresponding breaker and switchgear ratings.

• The short circuit evaluation would be based on:

⎯ A pre-fault voltage of 105% system nominal operating voltage.

⎯ Maximum operating load.

⎯ Motor contribution to the fault current would be included in accordance with

the applicable ANSI/IEEE standards.

⎯ Transformer impedances would reflec t negative manufacturing tolerance.

• Steady state voltage regulation during normal plant operation would be limited to a maximum of 110% of equipment rating during maximum system voltage and minimum bus loading, and would not fall below 90% of equipment rating during minimum system voltage and maximum bus loading.

• During motor starting, the voltage dip for medium-voltage motors would be limited to 80% of motor-rated voltage at the motor terminals when starting the largest single motor with maximum load on the bus. On the 480-V buses the level of voltage dip during motor starting would be limited to 80% of motor-rated voltage at the motor4-4 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 terminals when starting the largest single motor with maximum load on the bus. Additionally, the bus voltage at the MCCs would not be less than 85% of bus-rated voltage.

• The voltage regulation calculations would consider the minimum system operating voltage, maximum bus loading, and positive manufacturing tolerance for transformer impedance.

• The voltage level on the auxiliary buses during bus transfer would be sufficient to allow the reacceleration of the transferred medium voltage and low voltage motors in groups.

• The medium-voltage fast transfer scheme would be used for all bus transfers and would follow the scheme being utilized at the existing plant.



### 4.5 AUXILIARY POWER SYSTEM EQUIPMENT

4.5.1 SCR Option

All of the SCR auxiliary loads would be supplied from two (2) 4.16-0.48-kV USTs per unit. The 4.16-0.48-kV USTs would be connected to the existing 4.16-kV FGD switchgear. Feeds from the USTs to the doubled-ended switchgears would be made by cable bus. The 480-V switchgears would be located in their associated unit’s pump building, where space is available for future equipment.

The main 480-V buses would be connected via a tie breaker. The 480-V switchgears would feed MCCs that in turn would feed all the 480-V motor and other loads. The 480-V switchgear and MCC current interrupting rating would be equal to or less than 65 kA.

MCCs would be radial-fed with no interconnecting ties between MCC buses. For Units 1 and 3, the 480-V MCCs would be located in new PDCs positioned near the SCRs. For Unit 2, where the SCRs are in relative close proximity to the Unit 2 pump building and there are space constraints on the ground for a PDC, the 480-V MCCs would be located in the Unit 2 pump building, where space is available for future equipment.

Anhydrous ammonia system loads would be fed from new MCCs. The 480-V MCCs would be located in a new PDC positioned near the anhydrous ammonia delivery area.

4.5.2 SCR and Baghouse Option

During normal operation, the new ID booster fans would be supplied with power from one (1) new three-winding 26-14.9-kV UAT for each unit. The HV winding of the UATs would be fed by tapping into the existing isolated phase bus ducts (IPBs). Each LV winding would feed a separate new 13.8-kV switchgear bus.

13.8-kV buses would be sized to accommodate the maximum rating of the new UAT windings. The 13.8-kV switchgears would be located in new PDCs. Refer to the General Arrangement drawing (Appendix I) for PDC location.4-5 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 During startup and shutdown, the new 13.8-kV buses that feed the ID booster fans would be fed from existing main station serv ice (MSS) and reserve station service (RSS) transformers. MSS and RSS distribution w ould be supplied via two (2) new common 13.8-kV switchgears that would be tied to each unit switchgear by means of cable bus. The 13.8-kV Common switchgear would be located in a new PDC. Refer to the General Arrangement drawing (Appendix I) for PDC location.

An extension of the existing 4.16-kV swit chgear buses would be required. The buses to be extended are shown on One Line Drawings ESK-1001 SHT 1, 2 and 3 (Appendix F). Switchgear feeders would be added to provide feeds for the new 4-kV auxiliary air compressors associated with the baghouse and to service the 4.16-kV - 480-V transformers.

Two (2) 4.16-.48 kV USTs per unit would be required to service the 480-V loads. The 4.16-.48 kV UST would be connected to the extensions of the existing 4.16-kV FGD switchgear as described above. Feeds from the USTs to the double-ended switchgears would be made by cable bus. The 480-V switchgears would be located in their associated unit’s pump building, where space is available for future equipment.

480-V MCCs would service all smaller 480-V loads for the baghouse, SCR, and ID booster fans. For Units 1 and 3, the 480-V MCCs dedicated for SCR loads would be located in new PDCs positioned near the SCRs. Since the baghouse and ID booster fans are in relative close proximity to the unit pump buildings, the 480-V MCCs dedicated for baghouse and ID booster fan loads would be located in the unit’s pump building, where space is available for future equipment. All 480-V MCCs for Unit 2 would be located in the Unit 2 pump building, where space is available for future equipment.

Anhydrous ammonia system loads would be fed from new MCCs. The 480-V MCCs would be located in a new PDC positioned near the anhydrous ammonia delivery area.



### 4.6 DC POWER SUPPLY SYSTEM

The DC power supply system would consist of sealed-type VRLA batteries. The batteries would be sized to handle the duty cycles determined in the final design. All batteries would have design margin for future loads. Batteries would be able to supply full-duty cycle load for no less than two hours after loss of the charging system. Each battery would be furnished with two battery chargers. The battery chargers would be redundant. The batteries would be installed within the electrical equipment rooms.

Overcurrent protective devices would be provided in DC distribution panels with an interrupting capacity greater than the maximum available short circuit current. All cables in the DC distribution system would be designed to withstand the maximum available short circuit current.

The DC power system would feed the emergency bearing pumps for the ID booster fans, uninterruptible power supply (UPS) systems, and the control power for switchgear.4-6 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 4.7 UNINTERRUPTIBLE AC POWER SYSTEM

The uninterruptible AC power system would cons ist of a system that would provide regulated sinusoidal voltage to critical loads during normal and off-normal operations, as well as isolation of critical loads from transients generated on th e plant electrical auxilia ry system. The system would act as a source of uninterruptible power to critical loads in the event of failure of the normal AC power sources. The system would be designed with sufficient capacity to provide the peak demand currents of the connected loads and to clear branch circuit faults without adverse effects on the system. The syst em would include AC input rectifier, inverter, bypass power supply, static transfer switch, manual bypass switch, and UPS distribution panel boards with fast-acting current limiting type circuit breakers and fuses.

The UPS system would provide power to electrical loads, such as the DCS and instrumentation and controls, which require a regulated and AC uninterrupted power source.



### 4.8 ELECTRICAL CONTROL AND PROTECTION

Protective relaying systems would be designed to protect all electrical equipment in the main and auxiliary power supply systems. Protection would be provided for transformers as well as for the auxiliary power system and the loads connected to the auxiliary power system. The protective relay system would remove and alarm abnormal operating conditions occurring on equipment designed for voltage transformation, energy conversion, and distribution of electrical power, as well as limit damage to faulted or overloaded equipment. The protective relaying system would be a coordinated application of multif unction relays. All protective relays would be selected to coordinate with protective devices supplied by manufacturers of major equipment, as well as the thermal limits of electrical conductors and electrical equipment, such as transformers and motors.



### 4.9 COMMUNICATION SYSTEM

Communication systems for the new facilities w ould follow the existing plant communication systems. It is expected that the communication system extensions would be required for the following:

• Paging system

• Fire alarm and other signal systems

• Commercial telephone system



### 4.10 LIGHTING AND MAINTENANCE POWER SYSTEM

The lighting power system would consist of no rmal AC lighting, DC emergency lighting, and convenience receptacles. The lighting system woul d follow the lighting system at the existing plant. The lighting system would provide illumination for SCR and baghouse operation and maintenance under normal conditions, means of egress under emergency conditions, and emergency lighting in the equipment rooms to perform manual operations during a power outage of the normal power source. Emergency egress lighting would be powered self-4-7 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 contained battery packs, depending on the physical location of the emergency light fixture. Panelboards would be located indoors.

A maintenance welding system powered from the new 480-V system would be provided throughout the SCR and baghouse areas.



### 4.11 GROUNDING SYSTEM

The station grounding system would be extended with an interconnected network of bare solid copper conductors and copper ground rods. The systems would be designed to protect plant personnel and equipment from the hazards that can occur during power system faults and lightning strikes.

Major equipment items, such as switchgear, unit substation transformers, MCCs, and control panels, would have integral ground buses, which would be connected to the station ground grid. Electronic panels and equipment, where required, would be grounded utilizing an insulated ground conductor connected in accordance with the manufacturer's recommendations. The grounding system would be designed in accordance with applicable IEEE standards and would be installed in accordance with the NEC.



### 4.12 LIGHTNING PROTECTION SYSTEM

The lightning protection design would be in accordance with NFPA 780. Lightning protection for buildings and structures would consist of air terminals installed around the perimeter of the structure. The air terminals would be connected together with stranded copper conductors and connected to the plant ground grid with stranded copper down conductors.



### 4.13 CATHODIC PROTECTION SYSTEM

The existing cathodic protection system would be extended, as required, to provide corrosion control of buried metallic piping.



### 4.14 FREEZE PROTECTION SYSTEMS

Freeze protection system would be provided fo r outdoor piping (8” and smaller), instruments, and other devices subject to freezing in cold weather. The freeze protection system would be designed to accommodate both normal plant operations and extended plant shutdowns in cold weather. Similar systems and equipment would be utilized to meet process temperature maintenance needs of piping systems required to be maintained at high temperatures.



### 4.15 AUXILIARY POWER REQUIREMENTS

Addition of the major AQCS equipment will increase the auxiliary load of the plant. Also, the modification to the ID fans in the SCR Only option will use a greater amount of auxiliary power than currently used. Table 4-1 lists predict ed auxiliary power consumption for the new equipment.4-8 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Table 4-1. Predicted Auxiliary Power Consumption
Option Plant Auxiliary Power Unit Basis
Existing four (4) Induced Draft Fan Modification (increase BHP) 5.0 MW

Anhydrous Ammonia Storage and Transfer 0.1 MW SCR

SCR TOTAL 5.1 MW

SCR with DSI Existing four (4) Induced Draft Fan Modification (increase BHP) 5.0 MW

SCR and Sorbent Injection System 0.2 MW
Anhydrous Ammonia Storage and Transfer 0.1 MW

SCR with DSI TOTAL 5.3 MW
SCR and Sorbent Injection System 0.2 MW
Anhydrous Ammonia Storage and Transfer 0.1 MW
Existing Induced Draft Fan Modification (decrease BHP) and New ID Booster Fan 10.0 MW SCR + Baghouse

Baghouse Loads 0.5 MW

SCR + BAGHOUSE TOTAL 10.8 MW5-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 5. PLANT CONTROL SY STEMS AND EQUIPMENT

5.1 GENERAL

Triple instrumentation would be used on critical control loops and auxiliaries that if operated outof-limits would cause loss of power generation or catastrophic damage to a major plant auxiliary. The control logic would perform median select logic for analog loops and 2-out-of-3 logic for digital loops.

Dual instrumentation would be used for systems and auxiliaries that if operated out-of-limits would directly affect plant operation or cause damage to major auxiliaries. The control logic would perform average select logic of the tw o analog signals or 2-out-of-2 logic for digital signals.

Wherever possible, transmitters would be used in lieu of process switches. Transmitters would be electronic, 2-wire type, with isolated 4-20 mA DC output signals.

Temperature measurements for control and monitoring inputs would be made with RTDs or Chromel-Constantan (Type E) thermocouples.



### 5.2 SCR OPTION

The SCR system would be controlled by new DCS equipment that would be tied into the existing plant Foxboro DCS. New DCS equipment for Unit 1 and Unit 3 would be located in their respective new PDCs near the SCRs. New DCS equipment for Unit 2 would be located in the existing Unit 2 FGD pump house. The common DCS equipment for the anhydrous ammonia equipment would be located in the anhydrous ammonia unloading and storage area. All new DCS equipment would tie into the existing netw ork in the Environmental and Chemical Lab Control Room. The new Unit 1 and Unit 2 DCS equipment would tie into the existing cabinet 0- DCS-CABQ. The new Unit 3 and common DCS equipment would tie into the existing cabinet 0- DCS-CABR. Each Unit DCS would require 500 I/O points and the common DCS would require 100 I/O.

Each unit’s SCR has two reactors. Each reactor would require an in situ NO X and O 2 measurement on both the inlet and outlet side for a total of four measurements per unit. In addition to these measurements, a common meteorological station would also be added.

Each unit would require approximately 100 balance-of-plant instruments. These instruments include various transmitters, switches, thermo couples, etc., for the various SCR reactor measurements and new ID fan interface. The common DCS would require approximately 10 balance-of-plant instruments. These instruments include various transmitters, switches, thermocouples, etc., for the anhydrous ammonia unloading tanks and transfer pumps.

Minimal modifications may be required to the Control Room HVAC system controls to create a safe haven in the control room in the event of an ammonia leak.5-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 5.3 SCR AND BAGHOUSE OPTION

The SCR system would be controlled by new DCS equipment that would be tied into the existing plant Foxboro DCS. New DCS equipment for Unit 1 and Unit 3 would be located in their respective new PDC near the SCR, their respective PDCs housing 13.8-kV switchgear, and their respective FGD pump houses. New DCS equipment for Unit 2 would be located in the existing Unit 2 FGD pump house and the new Unit 2 PDC housing 13.8-kV switchgear. The common DCS equipment for the anhydrous ammonia equipment would be located in the anhydrous ammonia unloading and storage area and the common PDC building. All new DCS equipment would tie into the existing network in the Environmental and Chemical Lab ControlRoom. The new Unit 1 and Unit 2 DCS equipment would tie into the existing cabinet 0-DCSCABQ. The new Unit 3 and common DCS equipment would tie into the existing cabinet 0-DCSCABR. Each unit DCS would require 1000 I/O points and the common DCS would require 200 I/O points.

The Unit 1, 2, and 3 pulse-jet baghouse cleaning system would be controlled via the Vendor provided PLC. The PLC would have datalink integration into the new DCS. All other baghouse systems would be controlled via the DCS.

Each unit’s SCR has two reactors. Each reactor would require an in situ NO X and O 2 measurement on both the inlet and outlet side for a total of four measurements per Unit. In addition to these measurements, a common meteorological station would also be added.

Each unit would require approximately 150 balance-of-plant instruments. These instruments include various transmitters, switches, thermo couples, etc., for the various SCR reactor measurements, the new ID booster fans , and the new baghouse equipment. The common DCS would require approximately 10 balance-of-plant instruments. These instruments include various transmitters, switches, thermocouples, etc., for the anhydrous ammonia unloading tanks and transfer pumps.

Minimal modifications may be required to the Control Room HVAC system controls to create a safe haven in the control room in the event of an ammonia leak.6-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 6. PROJECT SCHEDULE

6.1 INTRODUCTION

Summary Level and Level III project schedules for development, design, construction, and startup of the project were prepared based on a multiple firm price construction contracting strategy. Construction-quality design drawings would be used for bidding purposes for the ductwork, structural steel, and foundations. The schedule, as currently laid out, represents the most cost effective and least risky option. However, there does exist some flexibility in activity durations, equipment lead times, and predecessor/successor relationships at the risk of higher financial expense.

The construction contracts would be:

• Substructure – Separate Contracts for Units 3, 2, and 1

• Mechanical & Structural General Work – Separate Contracts for Units 3, 2, and 1

• Electrical & Instrumentation General Work – Separate Contracts for Units 3, 2, and 1

• Construction Testing & Inspection

• Final Sitework

These schedules are provided in Appendix G.



### 6.2 PROJECT MILESTONES – SCR OPTION

The SCR Option schedules provided in Appendix G comprise an eight (8)-month engineering study phase, a twenty-nine (29)-month procurement and detailed engineering period, an eighteen (18)-month construction phase, and a two (2)-month tie-in. The total project duration, from study authorization to the completion of the tie-in outage is 42 months for Units 1 and 3, and 44 months for Unit 2. The construction and startup schedules including tie-in durations were furnished by Foster Wheeler and are also provided in Appendix G. The Foster Wheeler schedule was incorporated into the overall project schedule.

Development of the schedules was based on the following milestones: Table 6-1. SCR Option Schedule Milestones

Milestone Months After Notice To Proceed
Notice to Proceed (Unit 3) -
Purchase Catalysts 10
Notice to Proceed (Unit 2) 10
Receive Final Flow Model Report 16

Purchase Structural Steel 206-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Milestone Months After Notice To Proceed
Notice to Proceed (Unit 1) 24

Start Construction 25
Complete Tie In Outage (Unit 3) 42
Commercial Operation Unit 3 44
Complete Tie In Outage (Unit 2) 54
Commercial Operation Unit 2 56
Complete Tie In Outage (Unit 1) 66
Commercial Operation Unit 1 68



### 6.3 PROJECT PROCUREMENT – SCR OPTION

S&L’s initial determination of Unit 3 critical path is as follows: Table 6-2. Unit 3 SCR Option Critical Path

Activity Months After Notice to Proceed
Bid Issue Catalyst Specification 7
Award Catalyst Contract 10
Receive Final Flow Model Report 16

Bid Issue Structural Steel 17
Award Structural Steel Package 20
Release Foundation Design Package for Bid 19

Award Foundations Contract 22
Release M-GWC Design Package for Bid 21

Award M-GWC 24

Initial Ductwork Delivered Onsite 26
Release E-GWC Design Package for Bid 26

Award E-GWC 30
Complete Pre-Outa ge Construction 39
Complete Tie In Outage Unit 3 426-3 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 6.4 PROJECT MILESTONES – S CR AND BAGHOUSE OPTION

The SCR and Baghouse Option schedule comprises an eight (8)-month engineering study phase, a thirty-one (31)-month procurement and detailed engineering period, a nineteen (19)- month construction phase, and a two (2)-month tie-in phase. The total project duration, from study authorization to the completion of the tie-in outage is 48 months for Units 1 and 3, and 50 months for Unit 2. The construction and startup schedules were furnished by Foster Wheeler, and are also provided in Appendix G. The Foster Wheeler schedule was incorporated into the overall project schedule.

Development of the schedules was based on the following milestones: Table 6-3. SCR and Baghouse Option Schedule Milestones

Milestone Months After Notice To Proceed
Notice to Proceed (Unit 3) -
Purchase Catalysts 10
Notice to Proceed (Unit 2) 10
Purchase Baghouse 11
Receive Final Flow Model Report 16
Notice to Proceed (Unit 1) 24

Purchase Structural Steel 27

Start Construction 31
Complete Tie In Outage (Unit 3) 48
Commercial Operation Unit 3 50
Complete Tie In Outage (Unit 2) 60
Commercial Operation Unit 2 62
Complete Tie In Outage (Unit 1) 72
Commercial Operation Unit 1 746-4 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 6.5 PROJECT PROCUREMENT – SCR WITH BAGHOUSE

S&L’s initial determination of Unit 3 critical path is as follows: Table 6-4. Unit 3 SCR and Baghouse Option Critical Path

Activity Months After Notice to Proceed
Bid Issue Catalyst Specification 7
Award Catalyst Contract 10
Receive Final Flow Model Report 16

Bid Issue Structural Steel 24
Award Structural Steel Package 27
Release Foundation Design Package for Bid 24

Award Foundations Contract 28
Release M-GWC Design Package for Bid 26

Award M-GWC 30

Initial Ductwork Delivered On-Site 31
Release E-GWC Design Package for Bid 30

Award E-GWC 33
Complete Pre-Outa ge Construction 44
Complete Tie In Outage Unit 3 487-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 7. GENERAL ARRA NGEMENT FEATURES

7.1 COMMON

No significant changes to the existing drainage and roads in the area would be required to accommodate the new air quality equipment. Local modifications of these systems required in the area of the new work would tie back into the existing systems as quickly as possible.

Access roads would be maintained in the area of the new work. New pipe racks and ductwork that cross over or run along roads would be set at elevations high enough and with support column spacings wide enough to permit vehicle access below. For the purposes of this cost estimate the minimum clearance above all roads for vehicle access is 25 feet.



### 7.2 SCR OPTION

The two new SCRs for both Units 1 and 3 would be located side-by-side where possible for a more efficient ductwork arrangement as well as for better access and maintenance operations between the pair.

The new ductwork to and from the SCRs would exit the existing system downstream of the electrostatic precipitators and would tie back in upstream of the air heaters. These tie-ins would occur in the available space between the existing boiler building and the electrostatic precipitators.

7.2.1 SCR Unit 1

For Unit 1, the SCRs would be placed above the existing pipe rack that runs along the north side of the unit. The pipe rack would not be modified or affected in any way.

7.2.2 SCR Unit 2

For Unit 2, the SCRs would be separated from each other because of space constraints in this congested area. Separate SCRs would be placed to the north and south of the Unit 2 chimney.

Existing platforms that run between the Unit 1 and Unit 2 precipitators would be demolished to provide space for the new ductwork to and from the north SCR.

7.2.3 SCR Unit 3

For Unit 3, a portion of the existing maintenance facility / fabrication shop south the unit would be demolished to make room for the SCRs. For the purposes of this cost estimate space for a replacement facility for the demolished portion is reserved on the north side of the site.7-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 7.3 SCR AND BAGHOUSE OPTION

The two new baghouses and ID Booster Fans for each unit would be located side-by-side where possible for a more efficient ductwork arrangement as well as better access and maintenance operations between the pair.

For all units, the abandoned chimney shell would be used as a support for the ductwork going to and from the baghouses. A branch of ductwork would pass through the existing openings in the shell and additional openings would be cut as necessary, rather than demolishing the remaining shell and erecting new steel framing in the area to support the ductwork.

7.3.1 Baghouses Unit 1

For Unit 1, the baghouses would be located within the existing water treatment area and would be separated to avoid disturbing the existing equipment in the area.

The west Unit 1 baghouse, located between the exis ting brine concentrators and clarifier tanks, would be elevated above grade to maintain the roadway in the area, allowing for a 25-foot-high vehicle access below it.

The existing ash blowers and their foundation on the north side of Unit 1 would be relocated to accommodate the new ID Booster Fans. The existing pipe rack that runs along the north side of the unit would be demolished to accommodate the new fans. For the purposes of this cost estimate space is reserved for a replacement rack somewhat farther north of the existing one but still south of the water treatment area.

The existing sump and trenches in the water treatment area near the east Unit 1 baghouse would be relocated to accommodate the new baghouse.

7.3.2 Baghouses Unit 2

For Unit 2, the baghouses would be stacked because of the extreme congestion in the area. The existing tool room between the Unit 2 and Unit 3 precipitators would be demolished to make room for the baghouses. For the purposes of this cost estimate space is reserved for a replacement tool room on the north side of the site.

On Unit 2, the new ID Booster Fans would need to be separated to fit into the extremely congested area, with one on the north side of the Unit 2 chimney and the other on the north side of the Unit 3 chimney, south of the coal conveyor between Units 2 and 3.

The ductwork running to and from the Unit 2 baghouses would pass over and under both the existing coal conveyor that runs between Units 2 and 3 and also the new ductwork running to and from the south SCR for Unit 2. This congestion, coupled with the stacked baghouses for this unit, would put this ductwork at a higher elevation than it would need to be for the other two units.

For Unit 2, the existing opening in the abandoned chimney would be used for the baghouse supply duct, while the return duct from the baghouses, pushed higher by the stacked baghouses7-3 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 on this unit and the need to cross over the convey or and the SCR ductwork, would run over the top of the remaining portion of the shell.

On Unit 2, fitting the north ID Booster Fan into the tight area would require demolition of the existing stair tower / elevator adjacent to the Unit 2 pump enclosure. A bridge would be added between the Unit 1 and Unit 2 pump enclosures to provide access to the upper floor of the Unit 2 pump enclosure via the Unit 1 pump enclosure elevator. These existing stairs and elevator also provide access up to the top of the adjacent Unit 2 absorbers, so an alternate means of access to the absorbers that works around the various new items in the area would be provided.

A portion of the Unit 2 absorber foundation that supports this stair tower / elevator would also be demolished to accommodate the new fan foundation for the north ID booster fan.

7.3.3 Baghouses Unit 3

For Unit 3 no relocations of existing equipment or other major items would be required in the area of the new work. The pair of new baghouses and also the pair of new Booster Fans would fit side-by-side in an open area east of the existing fabrication shop / maintenance facility on the south side of Unit 3.8-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 8. UTILITY RELOCATION

8.1 PLANT UTILITIES

NGS is designed with water utility corridors and electrical ductbanks installed below grade. A major utility corridor is located north of Unit 1 and south of the water treatment facility along the east/west access road with branch distribution to the south of the plant. NGS has implemented a phased underground to aboveground (on piperacks) utility relocation plan. Refer to Appendix O for information provided by NGS regarding utilities currently relocated and plans for future relocation. For the purposes of this report, the basis of the cost estimate would be relocation of all identified utilities from underground to aboveground piperacks in line with current NGS relocation philosophy. The information provided by NGS in Appendix O would form the basis of a pipe relocation evaluation during the detailed engineering phase of the work. Additionally, for the purpose of this report, it is assumed the exis ting systems have sufficient capacity (pressure margin) to support relocation of utilities aboveground.

8.1.1 SCR Option

Based on preliminary review of the documents included in Appendix O, there are no piping relocations required to support installation of new equipment for the SCR Option. The cathodic protection system would most likely be affected from underground work. Modification to the system would be required as necessary. Existi ng platforms that run between the Unit 1 and Unit 2 precipitators would be demolished to provide space for the new ductwork to and from the north SCR of Unit 2. This would require the relocation of two (2) precipitator transformers from that platform to under the precipitator.

8.1.2 SCR plus Baghouse Option

To support installation of new infrastructure (piperack, baghouse, ductwork) for the Unit 1 SCR and Baghouse Option, a section of the major east/west underground utility corridor identified above would be required to be relocated. The existing pipe rack that runs along the north side of the unit would be demolished to accommodate the new booster fans. This would be replaced by a new rack located on the north side of the existing road. There are cables that run along the existing rack. These cables would be relocated to the pipe rack on the north side of the road. There are also distribution panels on the ground below existing rack that would need to be relocated. Relocation of the cables is assumed to only affect Unit 1. Detailed study / evaluation must be performed to identify service of each cabl e. Additionally, to support installation of the Unit 1 ID booster fans, a section of underground piping would be relocated just east of the new fans onto existing piperack. Any piping relocated to above ground would need to be heat traced.

To support installation of the Unit 2 baghouse, a section of aboveground ash conveying piping would be relocated east onto existing piperack. To support installation of the Unit 3 baghouse a short section of underground fire protection piping would relocated further south from the current installed location. Additionally, the existing tool room between the Unit 2 and Unit 3 precipitators would be demolished to make room for the Unit 2 baghouses. The existing tool room has cable trays loaded with cables running along side it. These cables would be relocated around the new baghouse by installing termination panels at the points where the cable need to be rerouted.8-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Relocation of these cables is assumed to only affect Unit 2. Detailed study / evaluation must be performed to identify service of each cable.9-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 9. PLANT ECONOMICS

9.1 BASIS OF COST ESTIMATES

9.1.1 General

The conceptual cost estimates provided in Appendix J are based on the installation of new NO X and particulate reduction equipment at NGS. Estimates 30621B, 30622B, and 30623B reflect the installation of SCR systems only on NGS Units 1-3 for NOx reduction. Estimates 30412E, 30413E, and 30414E reflect the installation of SCR systems only with dry sorbent injection on NGS Units 1-3 for NO X reduction. Estimates 30415E, 30416E, and 30417E include the addition of SCR systems as well as polishing baghouses for NO X reduction and particulate control on Units 1-3.

The cost estimates are conceptual in nature, and based largely on S&L experience on similar projects. No significant preliminary engineering has been performed to firm up the project details, and specific site characteristics have not been fully analyzed. Allowances have been added, where necessary, to cover issues that are likely to arise but are not clearly quantified at this time. Under AACE International’s guidelines these estimates could be classified as Class 4 Estimates. Class 4 estimates are generally prepared based on limited information, and subsequently, have fairly wide accuracy ranges . They area prepared for a number of purposes, such as but not limited to, detailed strategic planning, business development, project screening at more developed stages, alternative scheme analysis, confirmation of economic and or technical feasibility, and preliminary budget appr oval or approval to proceed to next stage.

9.1.2 Contracting Strategy

The capital cost for the plant modifications are based on Owner-managed engineering,procurement, and construction. Design of the plant would be performed by an architectengineer, hired by the Owner. All equipment w ill be purchased directly by the Owner and construction would be completed via a multiple lump sum contract arrangement.

9.1.3 Equipment Costs

The equipment costs include only those for the manufactured equipment. These items include, but are not limited to, anhydrous ammonia system, sorbent injection system, fans, fabric filters, compressors, dampers, transformers, switchgear , DCS, pumps, and motors. SCR catalyst is also included as equipment since it is purchased as a manufactured item. Informal budgetary quotes were obtained for the catalyst, anhydrous ammonia system, sorbent injection system, fabric filters, booster fans, compressors, and unit auxiliary transformers. All other equipment costs were estimated on the basis of S&L in-house data, vendor catalogs, industry publications, and other related projects.9-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 9.1.4 Material Costs

The material costs include those for commodity-type materials, such as structural steel, ductwork, concrete, piping, valves, cable, cable tray, and conduit. All material unit costs were estimated on the basis of S&L in-house data, vendor catalogs, industry publications, and other related projects. Quantities of materials were based on preliminary estimates by the project team.

9.1.5 Labor

An estimate of all construction-related costs, including construction management and startup and commissioning was prepared by Foster Wheeler. See “REV2_Basis of Labor Costs” in Appendix H. Additional information regarding the construction methodology that is used as the basis of the labor estimates is included in Section 10 of this report.

9.1.6 Labor Productivity

Labor productivity was accounted for in the cost estimates using two distinct factors. A regional productivity factor of 1.05 was applied to all direct labor work hours. This was the actual direct labor productivity experienced by Foster Wheeler on the Springerville Generating Station Unit 4 construction project. Another productivity factor based on the difficulty of each item of work was included in the line items in the estimate spreadsheets, based on the differing construction aspects for each unit. For more details see section 1.6 “REV2_Basis of Labor Costs” in Appendix H, and Section 10 of this report.

9.1.7 Project Indirect Costs

Indirect costs for hiring the architect-engineer were included in the estimates. Construction management and startup and commissioning costs prepared by Foster Wheeler were also included. Estimated owner’s capital costs are also included. Owner’s costs include owner’s construction management, ammonia unloading fac ility at railhead, legal support, insurance, operating and maintenance support during construction and start-up, spare parts, contract services, lost generation during short outages and sales taxes.

9.1.8 Escalation

Escalation is not included in the estimate. All costs are in 2010 dollars.

9.1.9 Contingency

The project contingency was determined using a technique called range analysis. The cost estimates were divided into major cost centers, such as equipment, catalyst, steel, other materials, labor, indirects, etc. High and low ranges were established for each of these cost centers. These ranges were then entered into a software program utilizing Monte Carlo Simulation to determine an overall contingency for the project. The Monte Carlo Simulation was based on running 10,000 iterations, where the inputs are randomly generated from probability distribution curves to simulate the process of sampling. The output is a curve, on which a point gives a percentage confidence factor and the corresponding overall dollar amount for the project9-3 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 to meet that confidence factor. For this project, we have used a 95% confidence factor to determine contingency dollars.

9.1.10 Allowance for Funds Used During Construction

Allowance for funds used during construction (AFUDC) has been calculated at 2.43% annual percentage rate.

9.1.11 Cash Flow

Quarterly cash flows were prepared based upon 42-month schedules for the SCR Option cost estimates and 48-month schedules for SCR and Baghouse Option cost estimates.



### 9.2 CAPITAL COST ESTIMATES

The capital cost estimates present the following cost breakdown for NGS:

• SCR

• Anhydrous Ammonia

• Sorbent Injection

• Baghouse

• Waste Collection System

• Flue Gas System & ID Fans

• BOP Piping & Equipment

• Electrical-Auxiliary Power

• Controls and Instrumentation

• New structures

• Removal and Relocation of existing equipment and infrastructure

• Site services/sitework

• Overtime, including Spot Overtime

• Contractor General & Administrative

• Contractor Profit

• Indirect Expenses

• Contingency

• Allowance for funds used during construction (AFUDC) The total estimated capital costs are as given below:9-4 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Table 9-1. Total Estimated Capital Cost Summary

Unit 1 SCR (Estimat e 30621B) $151,825,000

Unit 2 SCR (Estimate 30622B) $205,808,000

Unit 3 & Common SCR (Estimate 30623B) $186,528,000

Total for U1, U2, U3 SCR Only Option $544,161,000

Unit 1 SCR w/ DSI (Estimate 30412E) $154,946,000

Unit 2 SCR w/ DSI (Estimate 30413E) $209,324,000

Unit 3 & Common SCR w/ DSI (Estimate 30414E) $189,772,000

Total for U1, U2, U3 SCR Only w/ DSI Option $554,042,000

Unit 1 SCR & BH (Estim ate 30415E) $372,184,000

Unit 2 SCR & BH (Estim ate 30416E) $410,919,000

Unit 3 & Common SCR & BH (E stimate 30417E) $347,869,000

Total for U1, U2, U3 SCR and Baghouse Option $1,130,972,000



### 9.3 BUDGETARY QUOTES

9.3.1 SCR Catalyst

Budgetary-level quotes were anonymously solicit ed from five vendors for the SCR catalyst required to reduce the NO X emissions without increasing the SO 3 emissions above specified levels. These vendors are:

• Ceram

• Cormetech

• Haldor-Topsoe

• Hitachi

• Johnson Mathey

Quotes were received from Haldor-Topsoe and Johnson Mathey. These quotes, along with the letter specification sent to vendors, are included in Appendix K. Due to the ability to meet the required NO X emissions while also keeping the SO 3 emissions below specified levels, the9-5 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Haldor-Topsoe quote was determined to be the most technically feasible and the cost was used as the basis for the cost estimate.

9.3.2 Ammonia Storage and Feed System

Budgetary-level quotes were anonymously solicit ed from two vendors for the ammonia storage and feed system required to support the SCR operation. These vendors are:

• Chemithon

• Wahlco

Quotes were received from Wahlco. These quotes, along with the letter specification sent to vendors, are included in Appendix K. Subsequent to the initial solicitation, the total storage time for ammonia for the site was increased to 14 days. Revised pricing was solicited from Wahlco and has also been included in Appendix K in the form of an e-mail from Robyn Clark. Due to the ability to provide the ammonia in accordance with the letter specification, the Wahlco quote was determined to be the most technically feasible and the cost was used as the basis for the cost estimate.

9.3.3 Dry Sorbent Injection System

Budgetary-level quotes were anonymously solicit ed from three vendors for the dry sorbent injection system required to support the station subsequent to the installation of SCR systems. These vendors are:

• FLSmidth

• Nol-Tec

• UCC

Quotes were received from both Nol-Tec and UCC. These quotes, along with the letter specification sent to vendors, are included in Appendix K. Despite being more expensive, due to the ability to provide the dry sorbent injection system in accordance with the letter specification, the UCC quote was determined to be the most technically feasible and the cost was used as the basis for the cost estimate.

9.3.4 Pulse-jet Fabric Filter

Budgetary-level quotes were anonymously solicited fr om three vendors for the fabric filter, which may be required to reduce the particulate emissions for the site, with the ability to capture SO 3 , mercury, and fine particulate as well. These vendors are:

• Alstom

• Babcock & Wilcox (B&W)

• Hamon Research Cottrell (HRC)9-6 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Quotes were received from all three vendors. These quotes, along with the letter specification sent to vendors, are included in Appendix K. Due to the ability to meet the required PM emissions while also addressing the requirement for a stacked fabric filter for Unit 2, the B&W quote was determined to be the most technically feasible and the cost was used as the basis for the cost estimate.

9.3.5 ID Fans

Budgetary-level quotes were anonymously solicited from Howden for new ID booster fans for the SCR and Baghouse Option as well as full rotor and bearing replacement for the SCR Option.

Quotes were based on preliminary ID fan sizing calculations preformed by S&L and detailed in the Design Basis Document (Appendix A). Refer to Appendix K for the budgetary pricing quotes.

9.3.6 Pulse-jet Air Compressors and Auxiliaries

A budgetary-level quote was anonymously solicited from Atlas Copco for the pulse-jet air compressors and auxiliaries (aftercooler, air dryer and receiver tanks). The quote was based on sizing information provided to Atlas Copco. The methodology for the sizing is detailed in the Design Basis document Appendix A. Refer to Appendix K for the budgetary pricing quote.

9.3.7 Unit Auxiliary Transformers

Budgetary-level quotes were solicited from three vendors for the unit auxiliary power transformers required to support the station subsequent to the installation of SCR and Baghouse systems. These vendors are:

• ABB

• General Electric (GE)

• Niagra

Quotes were received from all three vendors. These quotes, along with the letter specification sent to vendors, are included in Appendix K. The Niagra quote was determined to be the most technically feasible by providing a detailed product quote and therefore the Niagra cost was used as the basis for the cost estimate.



### 9.4 O&M COSTS

9.4.1 Operating and Maintenance Costs

The conceptual operating and maintenance (O&M) cost estimates provided in Appendix J are based on the installation of new NOx and particulate reduction equipment at NGS. These were generated based upon the following three operating scenarios: SCR installation only; SCR and DSI; and SCR, DSI, and Baghouse.9-7 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 The cost estimates are conceptual in nature and based largely on S&L experience on similar projects. No significant preliminary engineering has been performed to firm up the project details and site specific characteristics have not been fully analyzed. Margin has been added to quantities, including sorbent feed rates, steam r equirements, auxiliary power consumption, etc., to provide conservatism to these cost estimates. A summary of these costs are shown below in Table 9-2. Table 9-2. Conceptual O&M Co sts (on a per Unit Basis)

V ariable O&M Unit Cost SCR Only SCR and DSI SCR and Baghouse Ammonia $475/ton 1,035,000 $ 1,035,000 $ 1,035,000 $ Catalyst Replacement $8,000/m3 672,000 $ 672,000 $ 672,000 $ Auxiliary Power $45/MW-hr 1,809,000 $ 1,880,000 $ 3,832,000 $ Steam $5/mmBtu 71,000 $ 71,000 $ 71,000 $ Sorbent (Hydrated Lime) $200/ton - $ 119,000 $ - $ Sorbent (Trona) $125/ton - $ - $ 71,000 $ Waste Disposal** $50/ton - $ 82,000 $ 32,000 $ Bag Replacement $100/bag - $ - $ 450,000 $ Cage Replacement $30/cage - $ - $ 45,000 $ Total Variable O&M* $/yea r 3,587,000 $ 3,859,000 $ 6,208,000 $
Fixed O&M SCR Only SCR and DSI SCR and Baghouse Maintenance Material $/year 237,000 $ 239,000 $ 402,000 $ Maintenance Labor $/year 158,000 $ 159,000 $ 268,000 $ Total Fixed O&M*** $/yea r 395,000 $ 398,000 $ 670,000 $ 

### Total O&M Cost* $/year 3,982,000 $ 4,257,000 $ 6,878,000 $ * Based on 90% Capacity Factor. ** Waste disposal cost represents levelized costs for trucking of waste to landfill site, development of landfill (dual liner with leachate collection system) and landfill maintenance. *** Operating & Maintenance - Maintenance, material and labor costs are calculated as a function of the overall capital cost for each option utilizing benchmarking data - SCR maintenance cost includes: ammonia unloading system monitoring, ammonia tank unloading, ammonia risk management plan, ammoni a tank inspection, maintenance of ammonia pumps, dilution air blowers, supporting components, and annual ammonia injection grid tuning - SCR only and SCR & DSI options, fixed O&M costs calculated based upon 0.2% of capital cost - SCR& Baghouse option, fixed O&M costs ca lculated based upon 0.25% of capital cost - SCR & Baghouse maintenance cost includes: 1% bag replacement every year, compressor maintenance, hopper heater main tenance, and ash handling system



### 9.5 TOTAL ANNUAL COSTS

9.5.1 Total Annual Costs

The total annual costs for the SCR option, SCR plus DSI option, and SCR plus Baghouse option are shown in Table 9-3. This table also includes a breakdown for each unit within each option.9-8 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 The total annual cost is the sum of the annual capital cost and the annual operating and maintenance cost. The annual capital cost has been calculated by multiplying the total capital cost by a Capital Recovery Factor (CRF) of 0.1159. The CRF of 0.1159 is based on an annual interest rate of 9.8% and amortization period of 20 years

Table 9-3. Levelized Annual Costs

SCR Option SCR with DSI Option SCR & Baghouse Option

Unit 1 Total Capital Cost $ 151,825,000 $ 154,946,000 $ 372,184,000 Annual Capital Cost (Total Capital Cost x CRF) $ 17,597,000 $ 17,958,000 $ 43,136,000
Annual O & M Cost $ 3,982,000 $ 4,257,000 $ 6,878,000 Total Annual Cost $ 21,579,000 $ 22,215,000 $ 50,014,000

Unit 2 Total Capital Cost $ 205,808,000 $ 209,324,000 $ 410,919,000 Annual Capital Cost (Total Capital Cost x CRF) $ 23,853,000 $ 24,261,000 $ 47,626,000
Annual O & M Cost $ 3,982,000 $ 4,257,000 $ 6,878,000 Total Annual Cost $ 27,835,000 $ 28,518,000 $ 54,504,000

Unit 3 Total Capital Cost $ 186,528,000 $ 189,772,000 $ 347,869,000 Annual Capital Cost (Total Capital Cost x CRF) $ 21,619,000 $ 21,995,000 $ 40,318,000
Annual O & M Cost $ 3,982,000 $ 4,257,000 $ 6,878,000 Total Annual Cost $ 25,601,000 $ 26,252,000 $ 47,196,000

Units 1,2,& 3 Total Capital Cost $ 544,161,000 $ 554,042,000 $ 1,130,972,000 Annual Capital Cost (Total Capital Cost x CRF) $ 63,069,000 $ 64,214,000 $ 131,080,000
Annual O & M Cost $ 11,946,000 $ 12,771,000 $ 20,634,000 Total Annual Cost $ 75,015,000 $ 76,985,000 $ 151,714,000 Capital Recovery Factor (CRF) = 0.1159 Based on an interest rate of 9.8% and amortization period of 20 years10-1 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

## 10. CONSTRUCTION AND CONSTRUCTIBILITY

As part of the cost estimating effort, Foster Wheeler, a major constructor for this type of work, was engaged to provide input into the construction aspects of the project. Input for this portion of the report has been provided by Foster Wheeler.



### 10.1 CONSTRUCTION SITE PLAN

10.1.1 Site Development and Temporary Facilities

It is expected that the NGS site already has sufficient, existing infrastructure and temporary facilities to support the Units 1-3 SCR and baghouse construction retrofit project. These required facilities include parking areas for construction craft labor and management staff personnel, phone service and temporary electrical power distribution for site construction management office trailers and facilities, pr epared material laydown and storage areas, and material assembly yards. The basis of this conceptual construction estimate is that sufficient facilities of this nature already exist to support mobilization of the required construction contractor(s).

10.1.2 Laydown, Fabrication, and Staging Areas

The construction plan is to use the existing prepared area southeast of Unit 3 for material laydown and ground-fabrication. This area was identified with the NGS management staff during the site visit of January 20-21, 2010, as the laydown and fabrication areas used for the prior scrubber retrofit projects. It is assumed that there is also existing space at site for storage of a limited amount of materials that would require climate-controlled storage. The basis of this conceptual construction estimate is that sufficient facilities of this type already exist at site.

10.1.3 Cranes and Heavy Lift Considerations

Foster Wheeler worked with Mammoet North America LLC (Mammoet) in the development of this estimate, to size the heavy lift cranes that would be required to support the installation strategy of ground-assembling at site, the SCR, baghouse, and flues into sections with weights ranging from 35-55 tons. Mammoet visited the NGS site on March 1-2, 2010 with Foster Wheeler and S&L representatives to review the conceptual arrangement drawings and the existing site conditions for the SCR and baghouse retrofit work.

Based on their review of the site, the drawings, and the installation strategy, Mammoet has provided general arrangement drawings for the placement of the selected cranes for each unit, for both the SCR Option and the SCR and Baghouse Option. Mammoet also provided the equipment description and pricing to receive, transport, and set one auxiliary transformer per unit. Further detailed description of the heavy-lift cranage to be used is included in subsections below.10-2 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

### 10.2 INSTALLATION METHODOLOGY

Foster Wheeler developed a preliminary Level I construction schedule for the work (see Appendix G), which has been incorporated into the overall schedule also shown in Appendix G. Foster Wheeler’s construction schedule is based on direct labor work hours estimated from the quantities provided by S&L. The construction sc hedule was used to determine the approximate durations required for the heavy-lift equipment, and to develop the histogram for the approximate craft labor manpower required for the work. With the limited information available at this time and the high-level nature of this construction estimate, further detailed installation sequence and plans have not been determined.

10.2.1 Substructure Work Based on previous experience with retrofit work on existing units, the construction estimate includes the cost of a specialty day-lighting contractor to determine any existing underground utilities or obstructions that may interfere with the installation of new underground materials.

10.2.2 Foundations

The basis of the estimate, from commodities to be installed, assumes that reinforcing bars, embedments and anchor bolts would be shop-fabricated to the maximum extent possible. It is also assumed that the concrete for foundations would be provided from an onsite batch plant.

10.2.3 Equipment Installation

In the SCR Option scenarios for the work, the ID fan rotors would be replaced. Work hours have been applied for the activity based on prior experience with rotor replacements in similar retrofit circumstances. The same information has been provided in the estimate for the new ID fans to be installed for the SCR and Baghouse Option scenarios, and for other miscellaneous equipment.

10.2.4 SCR and Flue Installation

The SCR materials are planned to be received at site in knocked down (flat) sections, consisting of casing plate with external stiffeners and attachments welded on in the fabrication shop. The materials received would be ground-assembled by site crews in the designated fabrication areas, to the maximum extent possible in order to minimize the erection time and congestion in the operating units.

Ground-assembly areas would be designated southeast of Unit 3, and assembly tables for the flues and reactors would be constructed there. Several fabricated panels would be assembled on the tables into components of pre-determined size and weight that can be safely transported,lifted and set into place at final elevation. Based on prior experience, the weight of the groundassembled components would range between 35-55 tons depending on installation access and final support details. When those parameters are further determined, the detailed installation sequence and final component sizes and weights may be identified, and rigging diagrams and analysis completed. The conceptual cost estimates include time for engineered rigging drawings10-3 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 to be produced for the critical component lifts, including constructability reviews for lifting lugs, spreader beams, etc.

The flue and reactor components would be ground-fabricated at an elevation that would allow for maximum installation of insulation, lagging, platforms and nozzles, and they would be accessible during ground-assembly by means of scissor and man-lifts. Some internal scaffolds may be required to install trusses and turning vanes, but in most cases it is expected that the assembly work would be done with lifts. The com ponent assembly dimensions would vary in width and height, not to exceed any existing conditions of the transport route to final location, which would be determined during the development of the engineered rigging drawings. The ground-assembled components would be moved from the assembly yard to the installation crane staging areas by 12-line hydraulic transporter.

All components that are insulated on the ground would have an un-insulated setback of approximately 1’-6” from the erection joint to allow for fit up and welding after the component is erected. Scaffolding would be required at these setback areas, when components are at final elevation to accomplish fit up, welding, and any remaining insulation that was either left off at the erection joints, or that could not be installed because of weight or dimension restrictions.

For the Unit 1 SCR Option, a 660-ton capacity crawler crane would be positioned south of the existing service building, and just west of the new SCR locations. Refer to crane placement drawing, Appendix E, Attachment 2, which illustrates the proposed location of the crawler crane in plan and elevation views and the associated lifting capacities at various radii.

For the Unit 2 SCR Option, a 1,250-ton capacity and a 660-ton capacity crawler crane would be needed due to the existing Unit 2 chimney blocki ng access to set certain new flue segments from just one location. The 1,250-ton crane would be positioned directly east of the existing Unit 1 pump building. The 660-ton crane would be positioned at the identified location north of the existing Unit 3 chimney. Refer to Appendix E, Attachment 4, which illustrates the proposed location of each crane in plan and elevation views, and the associated lifting capacities at various radii.

For the Unit 3 SCR Option, a 660-ton capacity crawler crane would be positioned in the existing parking lot, adjacent to and just south of the existing maintenance facility, which would be demolished to allow for the erection of both new SCRs. Refer to Appendix E, Attachment 6, which illustrates the proposed location of the crawler crane in plan and elevation views and the associated lifting capacities at various radii.

Structural steel support members and rack components would be ground-assembled into bents and structural modules where applicable, and are not expected to be critical lifts due to weight or size restrictions.

Piping would be double-jointed for rack piping and shop-fabricated to the maximum extent, including valves, that would allow for transport and erection.10-4 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 10.2.5 SCR Tie-In Work

Prior to the outage, the SCR and the new inlet and outlet flues would be installed up to the tie-in points for the precipitator plenums and the air pre-heater inlet plenums. The new SCR inlet flues, outlet flues and support steel would be installed to a point that would allow for the demolition of the existing flues and the installa tion of the new flues and blanking plates. Since the tie-in to the air pre-heater plenums is und er the existing lower precipitator plenum, the existing flues would be cut and lowered down to the new support steel bridging between the boiler structure and the precipitator structure. The demolished flues would be rolled out on a temporary handling system to a staging area wher e they can be lifted with the erection crane.

The new SCR outlet flues (or air pre-heater inlet flues) and blanking plates would then be set on the same staging area and rolled into place. The blanking plates would be set on top of the air pre-heater inlet flues, so that once they are rolled into place they can be fit and welded to the bottom of the remaining lower precipitator plenum. After the air pre-heater inlet flues are in place, the remaining SCR inlet support steel and flues would be erected and tied into the precipitator upper and lower plenums. Because of the proximity of the new versus the existing, it is expected that the air pre-heater inlet flues and blanking plates would be installed without being insulated in the ground-assembly area, and would be insulated after they are installed at elevation.

It is also expected that the startup and commissioning procedures would allow for the SCR catalyst and seals to be installed prior to the tie-in outage.

10.2.6 Baghouse Installation

The individual baghouse cells are expected to be shipped in shop-assembled modules. The hopper and roof sections would be ground-assembled in sections that can be safely transported and erected. The lower sections of the baghouse can be erected and accessed by man-lifts; however, after the lower sections are installed, scaffolding would be installed to complete the installation and for insulation purposes.

Because of the handling, fit-up and weld-out activities associated with the external sections of the baghouse, it would be erected bare, and insulated after all the seal welds have been leak tested. All flue sections from the baghouse to the axial fans and up to the tie-ins would be installed, leak-tested, and insulated prior to the outage. All seal welds on the flues, baghouses, SCR reactors, and air ducts would be leak-tested with bio-diesel and accepted by site quality inspectors prior to insulating. Final tie-ins would be accepted with the same process.

The two booster fans per unit would be completely in stalled with the exception of the tie-ins to the existing flues prior to the outage.

For the Unit 1 SCR and Baghouse Option, a second 660-ton capacity crawler crane would be required to install the baghouses and associated flues, in addition to the 660-ton capacity crane for the SCRs. For the elevated baghouse, the crane would be positioned in the existing roadway directly north of the new baghouse location. For the baghouse located at grade, the crane would be positioned in the existing roadway northeast of the new baghouse location. Refer to10-5 SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 Appendix E, Attachment 3 (4 sheets), which illustrates the proposed location of the crawler crane in plan and elevation views and the associated lifting capacities at various radii.

For the Unit 2 SCR and Baghouse Option, only the 1,250-ton capacity crawler crane would be required, with one relocation necessary. The relocation is necessary due to the existing Unit 2 chimney blocking access for setting certai n new flue segments and baghouse components. One crane setup position would be located directly east of the existing Unit 1 pump building, and directly north of the existing ash dewatering system. The other crane setup position would be located directly east of the existing Unit 2 pump building, and directly south of the existing ash dewatering system. Refer to Appendix E, Attachment 5, which illustrates the proposed location of each crane in plan and elevation views, and the associated lifting capacities at various radii.

For the Unit 3 SCR and Baghouse Option, a second 660-ton capacity crawler crane would be required to install the baghouses and associated flue sections north of the baghouse and west of the Unit 3 chimney. The second crane is in addition to the 660-ton capacity crane for the SCRs. The second crane would be positioned along the existing roadway directly south of the new baghouse locations. Refer to Appendix E, Attachment 7, which illustrates the proposed location of the crawler crane in plan and elevati on views and the associated lifting capacities at various radii.

10.2.7 Outage requirements

In order to relocate existing plant utilities and equipment to make room for the SCR and baghouse installation, it is anticipated that a short outage on the order of a week in duration would be required relatively early in the cons truction phase for each unit, about eighteen months prior to the major tie-in outage. Since this outage is not one of NGS’s regularly scheduled outages, the costs for lost generation associated with this outage have been included in the cost estimate. As shown in the preliminary construction schedule, it is expected that the major tie-in work for the SCRs and baghouses can be accomplished within the station’s scheduled 8-week outage durations. Since this major outage is one of NGS’s regularly scheduled outages, no additional costs for lost generation associated with this outage have been included in the cost estimate.



### 10.3 STARTUP AND COMMISSIONING

The preliminary Level I construction schedule developed in association with this estimate allows for approximately four months of startup and commissioning time. The schedule basis is that turnover of commissionable systems would start before the tie-in outage, and would conclude at approximately the completion of the outage.

Based on previous experience with retrofit work on existing units, the construction estimate includes the cost of startup and commissioning staff and craft labor based on a percentage of project direct labor expense. It is anticipated that the startup and commissioning personnel for the expected duration would include approximately one (1) commissioning manager, three (3) commissioning engineers, and a support craft labor cr ew of fifteen (15) direct craftsmen and (7) indirect craftsmen at peak. The cost of time at site for equipment vendor representatives is not included in this estimate.Appendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# A. D ESIGN 

# B ASIS

Item
SCR and Baghouse Capital Cost Estimate Design Basis, Revision B – April 16, 2010Appendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# B. C APITAL 

# C OST 

# E STIMATE 

# E QUIPMENT 

# L IST

Item
SCR Option Capital Cost Estimate Equipment List
SCR and Baghouse Capital Cost Estimate Equipment ListAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# C. C LIMATE 

# D ATAAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# D. P IPING AND 

# I NSTRUMENTATION 

# D IAGRAMS

No. Title
MSK-1002-01/02/03 Unit 1 Compressed Air System SCR and Baghouse (3 sheets)
MSK-1003-01 Unit 1 Ammonia Vaporizing and Dilution Air Skids
MSK-1004-01 Unit 1 Dry Sorbent Injection System Silo and Blowers
MSK-1005-01 Unit 1 Flue Gas System SCR and Baghouse
MSK-1005-02 Unit 1 Flue Gas System SCR
MSK-1006-01 Unit 1 Waste Ash System SCR and Baghouse
MSK-2002-01/02/03 Unit 2 Compressed Air System SCR and Baghouse (3 sheets)
MSK-2003-01 Unit 2 Ammonia Vaporizing and Dilution Air Skids
MSK-2004-01 Unit 2 Dry Sorbent Injection System Silo and Blowers
MSK-2005-01 Unit 2 Flue Gas System SCR and Baghouse
MSK-2005-02 Unit 2 Flue Gas System SCR
MSK-2006-01 Unit 2 Waste Ash System SCR and Baghouse
MSK-3002-01/02/03 Unit 3 Compressed Air System SCR and Baghouse (3 sheets)
MSK-3003-01 Unit 3 Ammonia Vaporizing and Dilution Air Skids
MSK-3003-02 Unit 3 Ammonia Vaporizing and Dilution Air Skids
MSK-3003-02 Units 1-3 Anhydrous Ammonia Unloading Stations and Storage Tank
MSK-3004-01 Unit 3 Dry Sorbent Injection System Silo and Blowers
MSK-3005-01 Unit 3 Flue Gas System SCR and Baghouse
MSK-3005-02 Unit 3 Flue Gas System SCR
MSK-3006-01 Unit 3 Waste Ash System SCR and BaghouseAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# E. C RANE 

# P LACEMENT

Att. No. Title

1. Level 1 Construction Schedule
2. Unit 1 SCR Only Lift Options
3. Unit 1 SCR & Baghouse Lift Options
4. Unit 2 SCR Only Lift Options
5. Unit 2 SCR & Baghouse Lift Options
6. Unit 3 SCR Only Lift Options
7. Unit 3 Baghouse Only Lift OptionsAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# F. E LECTRICAL 

# S INGLE 

# -L INE 

# D IAGRAMS

No. Title
ESK-1000 Option A, SCR Option - Units 1-3 and Common
ESK-1001 Option B, SCR and Baghouse Option - Unit 1
ESK-1001 Option B, SCR and Baghouse Option - Unit 2
ESK-1001 Option B, SCR and Baghouse Option - Unit 3Appendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# G. P ROJECT 

# S CHEDULES

Item

Foster Wheeler Schedule
SCR Option Level 1 Schedule
SCR Option Level 3 Schedule
SCR and Baghouse Option Level 1 Schedule
SCR and Baghouse Option Level 3 ScheduleAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# H. F OSTER 

# W HEELER 

# B ASIS OF 

# L ABOR

Att. No. Title
1. Not Used (see Foster Wheeler Schedule in Appendix G)
2. SCR and Baghouse Capital Cost Estimate
3. SCR and Baghouse Construction Estimate – Heavy Lift and Transportation
4. Mammoet Heavy Lift Proposal

5. Pullman Power Estimate
6. Construction Cost Estimate, Rev. 1Appendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# I. G ENERAL 

# A RRANGEMENT 

# D RAWINGS

No. Title
MSK-1000 Units 1-3 SCR Option Site Plan
MSK-1001 Units 1-3 SCR and Baghouse Option Site Plan (2 sheets)
MSK-1002 Unit 1 SCR Option Site Plan
MSK-1002 Unit 2 SCR Option Site Plan
MSK-1002 Unit 3 SCR Option Site Plan
MSK-1003 Unit 1 SCR and Baghouse Option Site Plan
MSK-1003 Unit 2 SCR and Baghouse Option Site Plan
MSK-1003 Unit 3 SCR and Baghouse Option Site PlanAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# J. C ONCEPTUAL 

# C APITAL 

# C OST 

# E STIMATES

Item/No. Title
Conceptual Cost Estimate Summary

Detailed Costs
30621A SCR Option Unit 1
30622A SCR Option Unit 2
30623A SCR Option Unit 3 and Common
30412D SCR with Dry Sorbent Injection Option Unit 1
30413D SCR with Dry Sorbent Injection Option Unit 2
30414D SCR with Dry Sorbent Injection Option Unit 3 and Common
30415D SCR and Baghouse Option Unit 1
30416D SCR and Baghouse Option Unit 2
30417D SCR and Baghouse Option Unit 3 and Common
Risk Analysis to Determine Contingencies
Quarterly Cash Flows

O&M CostsAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# K. S PECIFICATION 

# S UMMARY 

# P ACKAGES

Item
SCR Option Ammonia Storage and Feed System
SCR Option Catalyst
SCR Option Dry Sorbent Injection System
SCR Option ID Fan Rotor Replacement
SCR and Baghouse Option Pulse Jet Fabric Filters
SCR and Baghouse Option Air Compressor
SCR and Baghouse Option ID Booster Fans
SCR and Baghouse Option Un it Auxiliary TransformerAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# L. M ASTER 

# P ROCUREMENT 

# L ISTAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# M. M ODEL 

# F ILES 

# [.jsm Files]Appendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# N. M ODEL 

# V IEWS

Item

SCR Aerial

SCR Iso

SCR Plan

Unit 1 SCR West

Unit 2 SCR West

Unit 3 SCR West
Baghouse Aerial
Baghouse Iso
Baghouse Plan
Unit 1 Baghouse West
Unit 2 Baghouse West
Unit 3 Baghouse WestAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# O. SRP-P ROVIDED 

# D ATA Appendix O.1 - Underground Piping

No. Title
A-665-C143 Key Plan

A-665-C148 Area Plan Sheet 5

A-665-C149 Area Plan

A-665-C150 Area Plan Sheet 7

A-665-C151 Area Plan Sheet 8

A-665-C152 Area Plan Sheet 9

A-665-C153 Area Plan Sheet 10

A-665-C154 Area Plan Sheet 11

A-665-C155 Area Plan Sheet 12

A-665-C165 Area Plan Sheet 22

A-665-C169-1 Area Plan Crystallizer Building, Brine Concent rators, Cooling Tower, Blow Down Surge Tanks, Condensate Storage Tank

A-665-C169-2 Brine Concentr ator and Crystallizer Area

A-665-C262 Water Treatment Area PlanAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# O. SRP-P ROVIDED 

# D ATA

Appendix O-3 – HowdenAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# O. SRP-P ROVIDED 

# D ATA Appendix O-4 – Navajo QuestionnaireAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# O. SRP-P ROVIDED 

# D ATA Appendix O-5 – SGS Coal AnalysisAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# O. SRP-P ROVIDED 

# D ATA Appendix O-6 – Flue Gas

No. Title
- APH Flue Gas Inlet Temp
- ESP Outlet Flue Gas Temp vs Load

- Historian Data List

- NOx vs Load

- O2 vs Load
SK92-M0018 Air/ Gas Sys. Static Pressure ProfileAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# O. SRP-P ROVIDED 

# D ATA Appendix O-7 – Acid Mist Sampling

No. Title
- Rev-Pt1of2 Navajo Acid Mist 264-001 11-16-09
- Rev-Pt2of2 Navajo Acid Mist 264-001 11-16-09Appendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# O. SRP-P ROVIDED 

# D ATA Appendix O-8 – Equipment Data

No. Title

- Air Preheater

- FD Fans

- ID Fans
- Precipitator

- Steam GeneratorAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# P. N ATIONAL 

# P ARK 

# S ERVICE 

# & E NVIRONMENTAL 

# P ROTECTION 

# A GENCY 

# C OMMUNICATIONS

No. Title
1 Minutes of SRP/ NPS meeting July 20, 2010
2 Summary of NPS comments and SRP responses

3 SRP and NPS email communication
4 SRP Responses to EPA comments in 8/24/2010 meeting
5 Calculation of cost using EPA Pollution Control Cost Manual (PCCM)Appendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# Q. P RESENTATION FOR 

# NPSAppendixes SL-010214 Revision D

Navajo Report SCR and BH Cost Est Rev D.docx August 17, 2010 Project No. 12656-001 

# A PPENDIX 

# R. P RESENTATION FOR 

# EPA