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IMPLEMENTATION REVIEW PLAN Wolf Creek Dam, Cumberland River, Russell County, KY Dam Safety Project Nashville District 10 January 2013 MSC Approval Date: Pending Last Revision Date: 12 December 2012

IMPLEMENTATION REVIEW PLAN Wolf Creek Dam, Cumberland

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IMPLEMENTATION REVIEW PLAN Wolf Creek Dam, Cumberland River,

Russell County, KY Dam Safety Project

Nashville District

10 January 2013 MSC Approval Date: Pending

Last Revision Date: 12 December 2012

IMPLEMENTATION REVIEW PLAN

Wolf Creek Dam, Cumberland River,

Russell County, KY

Dam Safety Project

TABLE OF CONTENTS

1. PURPOSE AND REQUIREMENTS ..............................................................................................................1

a. Background and Purpose ………….......................................................................................................1

b. References..........................................................................................................................................1

c. Requirements...................................................................................................................................1

2. REVIEW MANAGEMENT ORGANIZATION (RMO) COORDINATION ..........................................................2

3. STUDY INFORMATION and DESIGN INFORMATION………………….............................................................2

a. Decision Document. ..........................................................................................................................2

b. Design ………………………………………………………………………………………………………………………….…………….2

c. Study/Project Description. ...............................................................................................................2

d. Factors Affecting the Scope and Level of Review.............................................................................4

e. In-Kind Contributions. .......................................................................................................................5

4. DISTRICT QUALITY CONTROL (DQC) ........................................................................................................5

a. Documentation of DQC ....................................................................................................................5

5. AGENCY TECHNICAL REVIEW ...................................................................................................................6

a. Products to Undergo ATR ................................................................................................................7

6. INDEPENDENT EXTERNAL PEER REVIEW ..................................................................................................7

a. Decision on Type I IEPR ..................................................................................................................7

b. Products to Undergo Type I IEPR ...................................................................................................7

7. TYPE II IEPR SAFETY ASSURANCE REVIEW (SAR)…....................................................................................8

a. Decision on Type II IEPR ................................................................................................................8

b. Products to undergo Type II IEPR...................................................................................................9

c. Panel Requirements for Type II IEPR .............................................................................................10

d. Required Type II IEPR Panel Expertise………………………….………………………………………………………….10

e. Documentation of Type II IEPR ......................................................................................................11

8. POLICY AND LEGAL COMPLIANCE REVIEW.............................................................................................11

9. MODEL CERTIFICATION AND APPROVAL .................................................................................................11

10. EXECUTION PLAN - SCHEDULE AND COST.............................................................................................12

a. Type II IEPR (SAR) Review Schedule and Cost .......................................................................12

b. Overall Schedule ..................................................................................................................13

11. PUBLIC PARTICIPATION ......................................................................................................................13

12. REVIEW PLAN APPROVAL AND UPDATES...........................................................................................13

13. REVIEW PLAN POINTS OF CONTACT ..................................................................................................13

ATTACHMENT 1: REVIEW PLAN SCHEDULE…………………………………………………………………….….……….…...14

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1. PURPOSE AND REQUIREMENTS

a. Background and Purpose Wolf Creek Dam is currently a Corps Dam Safety Action Classification I (DSAC I) dam in Russell County, Kentucky. It impounds Lake Cumberland, the largest storage reservoir of the Corps of Engineers east of the Mississippi River. It provides flood damage reduction, hydropower, recreation, navigation, water supply, and water quality benefits for the Cumberland River system and surrounding region. The project was designed and constructed from 1938 to 1952. The dam is a rolled earth-fill and concrete gravity structure that is 5,736 feet long. Chronic seepage problems originating from 1940’s foundation construction methods have worsened and threatened the stability of the dam. A Major Rehabilitation Evaluation Report (MRER) to address the seepage issues of the project was approved in August 2005. The recommended remediation plan consists of constructing a concrete diaphragm cutoff wall 275 feet deep immediately upstream of the concrete portion of the dam and extending 4,200 feet along the embankment to the right abutment. A grouting program was initiated in 2007 and construction of the diaphragm cutoff wall commenced in 2008. The cutoff wall is scheduled for completion in 2013 and the $594M project is 80% complete.

This review plan defines the scope and level of review for the completion of the project’s construction elements and ultimate return of the project to normal operation. The remaining construction elements include the cutoff wall, removal of stone off the upstream face of the dam’s embankment, and a wave run-up barrier on top of the embankment. The Review Plan is a component of the project’s Quality Management Plan in the overall Project Management Plan.

b. References (1) Wolf Creek Dam Major Rehabilitation Evaluation Report, August 2006

(2) Engineering Circular (EC) 1165-2-214, Water Resources Policies and Authorities, Civil Works Review.

(3) EC 1105-2-412, Assuring Quality of Planning Models, 31 March 2011

(4) Engineer Regulation (ER) 1110-2-12, Quality Management, 30 September 2006

(5) Wolf Creek Dam Seepage Major Rehabilitation Project Management Plan, October 2012

(6) Engineering Regulation (ER) 1110-2-1156, Safety of Dams – Policy and Procedure, 28 October 2011

(7) ER 1105-2-100, Planning Guidance Notebook, 22 April 2000, Appendix H, Policy Compliance Review and Approval of Decision Documents, Amendment # 1, 20 Nov 2007

(8) Engineering Regulation (ER) 10-1-51 Roles and Responsibilities, Dam Safety Modification Mandatory Center of Expertise, 29 June 2012

c. Requirements This review plan was developed in accordance with EC 1165-2-214, which establishes an accountable, comprehensive, life-cycle review strategy for Civil Works products by providing a seamless process for review of all Civil Works projects from initial planning through design, construction, and operation, maintenance, repair, replacement and rehabilitation (OMRR&R). The EC outlines four general levels of review: District Quality Control/Quality Assurance (DQC), Agency Technical Review (ATR), Independent External Peer Review (IEPR), and Policy and Legal Compliance Review. In addition to these levels of review, decision documents are subject to cost engineering review and certification (per EC 1165-2-214) and planning model certification/approval (per EC 1105-2-412). All expected elements of this

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project have been incorporated into the Total Project Cost estimate. The less than 1% of the project elements that have not been incorporated into an Independent Government Estimate do not reach the threshold for requiring a review by the Cost Engineering Center of Expertise as described in ER 1110-2-1302; and thus, this CX is not incorporated into this Review Plan.

2. REVIEW MANAGEMENT ORGANIZATION (RMO) COORDINATION The Review Management Organization (RMO) is responsible for managing the overall peer review effort described in this Review Plan. The RMO for decision documents is typically either a Planning Center of Expertise (PCX) or the Risk Management Center (RMC), depending on the primary purpose of the project. Since the primary purpose is Dam Safety, the RMO for the peer review efforts described in this Review Plan is the Risk Management Center (RMC). The RMC will maintain review management for the remainder of the project construction.

3. STUDY and DESIGN INFORMATION

a. Decision Document The major decision document for this project is the Major Rehabilitation Evaluation Report (MRER) approved by HQUSACE in 2005. Most of the components recommended in that plan have either been constructed or are nearing completion.

b. Design All major design efforts have been completed for the project and all features are either completed or under construction.

c. Study/Project Description Wolf Creek Dam is located at mile 460.9 of the Cumberland River near Jamestown, Kentucky. It is a combination concrete gravity and earth fill structure. The 1,796 ft long concrete section ties into the left abutment and extends across the old river channel toward the right abutment. It has a maximum height of 258 ft above founding level. The masonry dam contains a control section constructed in the old river channel, a powerhouse to the right of that and non-overflow sections on either end. The control section contains a spillway with ten 50-foot by 37-foot tainter gates and six 4-foot by 6-foot low level sluices. The powerhouse contains six turbines rated at 45,000 kw each. From the end of the concrete gravity section, a non-zoned compacted clay embankment with a maximum height of 215 ft above top of rock extends 3,940 ft across the valley to the right abutment. US Highway 127 traverses the dam. There are limited outlets (6 penstocks and 6 sluices) for emergency drawdown of the reservoir.

The project normally stores about four million acre-feet, with up to six million acre-feet maximum storage. The reservoir is the ninth largest in the United States and the Corps' largest reservoir in the eastern U.S.

The Wolf Creek project was authorized by the Flood Control Act of 1938 (Public No. 761, 75th Congress, 3d session). The dam and power plant were designed and constructed during the period 1938-1952. Construction began in 1941 and was interrupted from 1943-1946 due to WWII. The reservoir was impounded in December of 1950. In the late 1970's two concrete diaphragm walls were installed to correct serious seepage problems. One wall was constructed from the dam crest along 2,200 feet of the embankment. The second wall extended from the power plant along the left perimeter of the switchyard. This wall prevents tail water fluctuations from removing material from the switchyard rock

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foundation.

Since completion of the walls in 1979, District personnel continued to closely monitor the project, and observed increasing impacts and abnormal conditions. Key instrumentation readings, persistent and increasing wet areas, and investigative borings that encountered very soft, wet material at depth in the embankment all confirmed that solution features still existed that were not been cut off. While the original wall interrupted progression of piping just short of failure, seepage continued to find new paths under and around the wall and perhaps through defects in the wall itself as erosion of solution features continues at an ever-increasing rate. According to the findings of the MRER, Wolf Creek Dam was in the progression stage for some time since the completion of the 1979 wall and without timely intervention, would result in a breach of the embankment. The risk was heightened by the fact that piping can rapidly progress with little or no warning to a point that precludes successful intervention. Waiting for additional indications or pursuing a fix-as-fails approach likely will result in a drastic pool lowering or dam failure.

Failure would be catastrophic. Loss of life is expected to exceed one-hundred lives. Economic losses are estimated in the billions with damages as distant as Nashville, Tennessee expected to exceed $2 billion. Short of a complete breach, any future event that requires a significant lowering of the pool such as a new sinkhole, muddy flows, or significant changes in instrumentation readings would have significant economic and environmental impacts on the region.

As a result of these concerns, the MRER evaluated several alternatives to improve the long term reliability of the dam by using a reliability analysis based on an analytical model built upon historical instrumentation data. From this analysis, the recommended alternative, which is also the National Economic Development alternative, was a new concrete diaphragm wall constructed using the secant pile method and supplemented with grouting. This new wall starts immediately upstream of the right most concrete monoliths and run the length of the embankment into the right abutment. It is being constructed to a depth which is deeper than the deepest sections of the original wall and as much as 75 feet deeper than the majority of the original wall.

Construction of the cutoff wall is nearing completion – it is 93% complete as of December 2012 and is expected to be fully completed by early spring 2013.

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Figure 1: Location of Wolf Creek Dam

d. Factors Affecting the Scope and Level of Review The following factors will affect the project and level of review: (1) Evaluation of the monitoring and exploratory data garnered since the original reliability report was

approved in 2005, and the assessment of residual risk after project construction is complete. (2) Evaluation of the quality control data collected during all phases of construction to ensure that adequate measurements and analysis have been completed and that results are within tolerable requirements. (3) The project with the recommended actions have a tolerable risk level in terms of failure potential and life safety risks which are described in the formal Risk Analysis. (4) There has been no request for peer review by the governor of Kentucky. (5) The Post Construction Risk Assessment for revision of Dam Safety Action Classification will be subject to a safety assurance review (Type II IEPR).

e. In-Kind Contributions There are no In-Kind Contributions for this project.

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4. DISTRICT QUALITY CONTROL (DQC) All decision documents and supporting design documents (including supporting data, analyses, environmental compliance documents, etc.) shall undergo DQC. DQC is an internal review process of basic science and engineering work products focused on fulfilling the project quality requirements defined in the Project Management Plan (PMP).

a. Documentation of DQC The DQC on the Project has been managed by the District in accordance with ER 1110-1-12. The DQC team members represented the following disciplines: Geology and Geotechnical Engineering, Structural Engineering, Hydrology and Hydraulic Engineering, Construction, Cost Estimating, Environmental Planning/NEPA, HTRW, Cultural Resources and Real Estate. In addition to inhouse personnel, DQC is being supplemented on this project by an outside panel of experts. This Advisory Panel consists of up to four members with expertise in various subfields of geology and geotechnical/dam safety engineering. The three tables below list the current teams involved in the production and reviews for the project. All DQC shall be documented through use of the DrChecks system. The DQC shall not be considered complete on a work product until all comments have been closed in DrChecks.

5. AGENCY TECHNICAL REVIEW ATR is mandatory for all decision documents (including supporting data, analyses, environmental compliance documents, etc.). The objective of ATR is to ensure consistency with established criteria, guidance, procedures, and policy. The ATR assesses whether the analyses presented are technically correct and comply with published USACE guidance, and that the document explains the analyses and results in a reasonably clear manner for the public and decision makers. ATR is managed within USACE by the designated RMO and is conducted by a qualified team from outside the home district that is not involved in the day-to-day production of the project/product. ATR teams will be comprised of senior USACE personnel and may be supplemented by outside experts as appropriate. The ATR team lead will be from outside the home MSC and team members are from outside the Nashville District.

a. Products to Undergo ATR. Products that require ATR are as follows:

1. No future products are anticipated to undergo ATR because of the advanced stage of the project is not producing these work products.

6. INDEPENDENT EXTERNAL PEER REVIEW IEPR is the most independent level of review, and is applied in cases that meet certain criteria where the risk and magnitude of the proposed project are such that a critical examination by a qualified team outside of USACE is warranted. A risk-informed decision, as described in EC 1165-2-214, is made as to whether IEPR is appropriate. IEPR panels will consist of independent, recognized experts from outside of the USACE in the appropriate disciplines, representing a balance of areas of expertise suitable for the review being conducted. There are two types of IEPR:

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• Type I IEPR. Type I IEPR reviews are managed outside the USACE and are conducted on project studies. Type I IEPR panels assess the adequacy and acceptability of the economic and environmental assumptions and projections, project evaluation data, economic analysis, environmental analyses, engineering analyses, formulation of alternative plans, methods for integrating risk and uncertainty, models used in the evaluation of environmental impacts of proposed projects, and biological opinions of the project study. Type I IEPR typically covers the entire decision document or action and will address all underlying engineering, economics, and environmental work, not just one aspect of the study. For decision documents where a Type II IEPR (Safety Assurance Review) is anticipated during project implementation, safety assurance shall also be addressed during the Type I IEPR per EC 1165-2-214. There are no decision documents or work products anticipated on the remainder of the project that would require a Type I IEPR.

• Type II IEPR. Type II IEPR, or Safety Assurance Review (SAR), are managed outside the USACE and are conducted on design and construction activities for hurricane, storm, and flood risk management projects or other projects where existing and potential hazards pose a significant threat to human life. Type II IEPR panels will conduct reviews of the design and construction activities prior to initiation of physical construction and, until construction activities are completed, periodically thereafter on a regular schedule. The reviews shall consider the adequacy, appropriateness, and acceptability of the design and construction activities in assuring public health safety and welfare. A Type II IEPR is planned for the Post Construction Risk Assessment for revision of Wolf Creek’s Dam Safety Action Classification.

b. Products to Undergo Type I IEPR. None

7. TYPE II IEPR SAFETY ASSURANCE REVIEW (SAR) Type II IEPR, also known as SAR, is conducted on design and construction activities for hurricane and storm risk management and flood risk management projects, as well as other projects where potential hazards pose a significant threat to human life. This applies to new projects and to the major repair, rehabilitation, replacement, or modification of existing facilities. The requirement for Type II IEPR is based upon Section 2035 of WRDA 2007, the OMB Peer Review Bulletin and other USACE policy considerations. External panels will conduct reviews of the design and construction activities prior to the initiation of physical construction and, until construction activities are completed, periodically thereafter on a regular schedule. The reviews shall consider the adequacy, appropriateness, and acceptability of the design and construction activities in assuring public health, safety, and welfare. The Review Management Office for Type II IEPR reviews is the USACE Risk Management Center (RMC). Panel members will be selected using the National Academies of Science (NAS) policy for selecting reviewers. Type II IEPRs are not exempted by statute from the Federal Advisory Committee Act (FACA). Type II IEPR procedures to follow are in Appendix E of EC 1165-2-214. The SAR will be concurrent with the ATR yet will not duplicate the ATR; SAR is a strategic level review.

The District Chief of Engineering and Construction, as the Engineer-In-Responsible-Charge, is responsible for ensuring the Type II review is conducted in accordance with this Circular, and will fully coordinate with the Chief of Operations, and the project manager through the Pre-Engineering and Design (PED) and construction phases. The project manager will coordinate with the RMO to develop the review requirements and to include them in the Review Plan. The RMO for Type II reviews is the USACE Risk Management Center.

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a. Decision on Type II IEPR. The Post Construction Risk Assessment for revision of Wolf Creek’s Dam Safety Action Classification will require a Type II IEPR Safety Assurance Review for its construction phase since it is a flood risk management project where the Federal action is justified by life safety and the failure of the project would pose a significant threat to human life. Other factors to consider for conducting a Type II review of a project or components of a project are listed in the table.

Type II IEPR Decision Factors

EC 1165-2-214 Criteria Wolf Creek Dam Safety Project

Does the project involve the use of innovative materials or techniques where the engineering is based on novel methods, presents complex challenges for interpretations, contains precedent-setting methods or models, or presents conclusions that are likely to change prevailing practices?

Yes. The secant pile wall currently being constructed is at a scale and scope never before attempted.

Does the project have redundancy, resiliency, and robustness?

The project has been designed to be robust and resilient, but redundancy is not economically feasible.

Does project have unique construction sequencing or a reduced or overlapping design construction schedule?

Construction sequencing has been challenging but is not unique.

For the PED or design phase, the SAR should focus on unique features and changes from the assumptions made and conditions that formed the basis for the design during the decision document phase. The SAR shall address the following questions:

1. Do the assumptions made during the decision document phase for hazards remain valid through the completion of design as additional knowledge is gained and the state-of-the-art evolves?

2. Do the project features adequately address redundancy, resiliency, or robustness with an emphasis on interfaces between structures, materials, members, and project phases?

3. Do the project features and/or components effectively work as a system?

For the construction phase, the SAR shall address the following questions:

1. Do the assumptions made during design remain valid through construction?

2. For O&M manuals, do the requirements adequately maintain the conditions assumed during design and validated during construction; and will the project monitoring adequately reveal any deviations from assumptions made for performance?

For establishing Type II – IEPR Panels the RMO is responsible for ensuring the panels are established in accordance with EC 1165-2-214.

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b. Products to Undergo Type II IEPR (SAR) The products to undergo Type II IEPR will include:

• Post Construction Risk Assessment for revision of Dam Safety Action Classification – It is envisioned that this Risk Assessment and associated IEPR will cover the gamut of the project. The design criteria and resulting designs will be reviewed to ensure that they met all the goals and standards established for the project. All construction elements will be reviewed to ensure they met design standards. Quality Control methods implemented during construction will be reviewed and resulting QC data will be reviewed to ensure the structural elements met all design standards and goals. Finally, monitoring of the dam’s performance both during and post construction will be reviewed to ensure appropriate conclusions have been made. Upon conclusion of this Risk Assessment and resolution of any issues raised through the IEPR, it is expected that a recommendation for a revision of Wolf Creek’s Dam Safety Action Classification will result.

c. Panel Requirements for Type II IEPR (SAR) The panel of experts established for a review for a project shall:

• Conduct the review in a timely manner in accordance with the study and RP schedule; • Follow the “Charge”, but request other relevant products as necessary; • Receive any public written and oral comments provided on the project; • Provide timely written and oral comments throughout project development, as requested; • Assure the review avoids replicating ATR and focuses on the “Charge” questions; the panel can recommend additional or alternate questions; • Offer any lessons learned to improve the review process. • Submit reports in accordance with the review plan milestones. • The team panel lead insures that comments represent the group, be non-attributable to individuals, and where there is lack of consensus, note the non-concurrence and why.

d. Required Type II IEPR (SAR) Panel Expertise This required panel expertise will be updated when design issues are better known. The following panel members are expected for the SAR: Geotechnical Engineer, Geologist, Structural Engineer, and a Specialist in Risk Assessment Methodology.

e. Documentation of Type II IEPR The review team will prepare a review report for the Wolf Creek Post Construction Risk Assessment. All review panel comments shall be entered as team comments that represent the group and be non-attributable to individuals. The team lead is to seek consensus, but where there is a lack of consensus, note the non-concurrence and why. The report outline is an introduction, the composition of the review team, a summary of the review during design, a summary of the review during construction, any lessons learned in both the process and/or design and construction, and appendices for conflict of disclosure forms, for comments to include any appendices for supporting analyses and assessments of the adequacy and acceptability of the methods, models, and analyses used. All comments in the report will be finalized by the panel prior to their release to USACE for

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final review and concurrence. SAR Panel Members Experience

Geotechnical Engineering and Dam Safety The Geotechnical engineer should have experience in soils engineering and dam safety risk evaluation through participation in dam safety expert panels, risk evaluation/mitigation

Geologist The Geologist should have experience in seepage in karst geology and dam safety instrumentation.

Structural Engineer The Structural engineer should have experience in underground concrete structures.

Specialist The specialist experienced in Risk Assessment Methodology

The host district Chief of Engineering and Construction is responsible for coordinating with the RMO, for attending review meetings with the SAR review panel, communicating with the agency or contractor selecting the panel members, and for coordinating the approval of the final report with the MSC Chief of Business Technical Division.

After receiving a report on a project from the peer review panel, the District Chief of Engineering and Construction, with full coordination with the Chief of Operations, shall consider all comments contained in the report and prepare a written response for all comments and note concurrence and subsequent action or non-concurrence with an explanation. The District Chief of Engineering and Construction shall submit the panel’s report and the Districts responses shall be submitted to the MSC for final MSC Commander Approval and then make the report and responses available to the public on the District’s website

8. POLICY AND LEGAL COMPLIANCE REVIEW

All decision documents will be reviewed throughout the study process for their compliance with law and policy. Guidance for policy and legal compliance reviews is addressed in Appendix H, ER 1105-2-100. These reviews culminate in determinations that the recommendations in the reports and the supporting analyses and coordination comply with law and policy, and warrant approval or further recommendation to higher authority by the home MSC Commander. DQC and ATR augment and complement the policy review processes by addressing compliance with pertinent published Army policies, particularly policies on analytical methods and the presentation of findings in decision documents.

9. MODEL CERTIFICATION AND APPROVAL EC 1105-2-412 mandates the use of certified or approved models for all planning activities to ensure the models are technically and theoretically sound, compliant with USACE policy, computationally accurate, and based on reasonable assumptions. Planning models, for the purposes of the EC, are defined as any models and analytical tools that planners use to define water resources management

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problems and opportunities, to formulate potential alternatives to address the problems and take advantage of the opportunities, to evaluate potential effects of alternatives and to support decision making. The use of a certified/approved planning model does not constitute technical review of the planning product. The selection and application of the model and the input and output data is still the responsibility of the users and is subject to DQC, ATR, and IEPR.

EC 1105-2-412 does not cover engineering models used in planning. The responsible use of well-known and proven USACE developed and commercial engineering software will continue and the professional practice of documenting the application of the software and modeling results will be followed. As part of the USACE Scientific and Engineering Technology (SET) Initiative, many engineering models have been identified as preferred or acceptable for use on Corps studies and these models should be used whenever appropriate. The selection and application of the model and the input and output data is still the responsibility of the users and is subject to DQC, ATR, and IEPR.

Models Used for Dam Safety

Model Name Model Description Model Type

HEC-FIA Economic model used to calculate estimated economic damages and loss of life corresponding to floodplain mapping.

Planning Approved for use

DAMRAE (DAM Safety Risk Analysis Engine)

This is a generalized event tree analysis tool that includes a graphical interface for developing and populating an event tree, and a tool for calculating and post-processing an event tree risk model for dam safety risk assessment.

Engineering Preferred Model

HEC-HMS By applying this model the PDT is able to: a. Define the watersheds’ physical features b. Describe the metrological conditions c. Estimate parameters d. Analyze simulations e. Obtain GIS connectivity

Engineering Preferred Model

Model Name Model Description Model Type

HEC-RAS and HEC-GeoRAS Unsteady 1-dimensional flow model used to simulate the channel hydraulics from Center Hill Dam 26 miles to its confluence with the Cumberland and 308 miles to the confluence with the Ohio River

Engineering Preferred

MCACES or MII These are cost estimating models developed by Building Systems Design Inc. Crystal Ball risk analysis software will also be used.

Cost Estimating

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10. EXECUTION PLAN - SCHEDULE and COST

a. Type II IEPR (SAR) Review Schedule and Cost The Type II IEPR is estimated to be $250,000 for this effort.

Type II IEPR Schedule Task Date

SAR team identified 30 May 2013 Attend Post Construction Risk Assessment 15 July 2013

Complete initial review 15 Aug 2013 Address comments 15 September 2013 Finalize review and approval 15 October 2013

b. Overall Schedule Attachment 1 contains an execution plan/schedule to complete the project, including the Type II IEPR. This includes the ultimate review and approval by the Dam Safety Senior Oversight Group that will allow Wolf Creek Dam to be reclassified to a lower risk DSAC rating.

11. PUBLIC PARTICIPATION Numerous public meetings were held for the MRER and the public has been kept informed of the project’s progress through a robust project website and frequent briefings to interested groups and officials.

12. REVIEW PLAN APPROVAL AND UPDATES

The Great Lakes and Ohio River Division Commander is responsible for approving this Review Plan. The Commander’s approval reflects vertical team input (involving district, MSC, RMO, and HQUSACE members) as to the appropriate scope and level of review for the decision document. It is expected that the appropriate Flood Risk Management Business Line Managers will be included in the review of the Review Plan. Like the PMP, the Review Plan is a living document and may change as the study progresses. The home district is responsible for keeping the Review Plan up to date. Significant changes to the Review Plan (such as changes to the scope and/or level of review) should be re-approved by the MSC Commander following the process used for initially approving the plan. The latest version of the Review Plan, along with the Commanders’ approval memorandum, should be posted on the Home District’s webpage. The latest Review Plan should also be provided to the RMO and home MSC.

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13. REVIEW PLAN POINTS OF CONTACT Questions and/or comments about this Review Plan may be directed to the following points of contact: Don Getty, Project Manager, 615-736-2346.

Jun J A S O N D Jan F M A M J J A S O N D Jan F M A M J J A S O N D

∆PDT/RMC/Adv Panel Switchyard and QC Review Meeting

∆Dam Safety SOG Review and Concurrence with pool raising schedule/plan

Revise IRRMP and IOP to reflect criteria for interim pool level in 700 to 705 range

Review and approval of revised IRRMP and IOP by LRD

∆PDT/RMC/Advisory Panel/LRD/HQ Final QC Review Meeting

∆Complete Barrier Wall/green light to operate pool at interim elevation of 700

Post construction monitoring

Initiate Type II IEPR

Lower Pool to 695

Remove rock on upstream embankment/wrap-around

LRN Revision of Risk Analysis for Post Construction

∆ PDT/RMC/Advisory Panel/IEPR Risk Analysis and monitoring Rev. Mtg

Type II IEPR Review of Risk Analysis∆

Compl. Type II IEPR Review - Recommendation of DSAC Reclass.

Dam Safety SOG Review and Concurrence with DSAC Reclassification

Return to historical pool operations

Attachment 1 - Wolf Creek Dam Safety Review Plan Schedule

Calendar Yr. 2012 Calendar Yr. 2013 Calendar Yr. 2014