How To Build A Powerhouse

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1 Ozark and Webbers Falls Powerhouse Major Rehabilitation Lee Beverly- SWL Project Manager Dan Brueggenjohann SWT Project Manager Byron Floyd Resident Engineer 12 June 2013 US Army Corps of Engineers

2 Ozark Scope, Cost and Schedule Project Scope: Rehabilitation of the Ozark Powerhouse to include replacement of five turbines, rehabilitation of all cranes, rehab of water Treatment, and misc aux systems Project Cost including management expenses: $125.7M ($32.9M Customer Funded) Turbine Contract Notice to Proceed : July 2005 Awarded Turbine Contract Amount: $74.5M Current Turbine Contract Amount: $99.0M Current Required Completion Date : April 20, 2014 Anticipated Completion Date: March 24, 2017

3 Ozark Funding Status Ozark Rehab Project Estimate Cranes, Gates, Generator Coolers, Plant Prep (note, includes speed increaser credit mod) Turbine Contract Engineering, Project Support, Contract Mgmt Remaining Escalation Payments (based on 7 th yr esc. Factors) Contingency $125.7M $3.9M $93.5M $17.6M $5.8M $4.9M Funding Received to Date Regular Appropriations Recovery Act Funding FY06-FY07 Customer Funding FY12 Customer Funding $107.2M $44.6M $29.7M $20.1M $12.8M Balance To Complete $18.5M Ozark/Webbers Falls Major Rehab

4 Ozark Turbine Replacement Contract Major Modifications to date- Replace Cooling Water Systems- $800,000 Replace Unwatering Systems- New Upper Shafts- Correct Misalignments, Unit 4- $1.0 Million 3.2 Million $2.0 Million Paint Blades and Wicket Gates $800,000 Stay Vane Repair, 3 Units (est)- Additional Interior Painting Escalation Thru June 2012 $1.6 Million $1.4 Million $5.3 Million BUILDING 4 STRONG

5 Ozark/Webbers Falls Economic Price Adjustments (escalation) The 7 th year escalation payment was 8.8% of the total invoicing

6 Webbers Falls Scope, Cost and Schedule Project Scope: Rehabilitation of the Webbers Falls Powerhouse to include replacement of three turbines, the rewinding of three generators and rehabilitation of all cranes, tailrace and intake gates and bulkheads. Project Cost including management expenses: $72.7M ($67.9M Customer Funded) Turbine Contract Awarded: February 2008 Awarded Turbine Contract Amount: $39.3M Current Turbine Contract Amount: $45.9M Current Required Completion Date : 4 October 2012 Anticipated Completion Date: 16 January 2016

7 Webbers Falls Project Cost Breakdown 2013 Current Cost Est. - $72.7M Turbine Rehab Cont Generator Rewind Cont Intake/Draft Tube Cranes 4.0* Rehab Two Bridge Cranes 2.6 Misc. Electrical Mech ** New 13.8KV Breakers - 0.8* Total - $72.7M *ARRA Funded **Partial ARRA Funded Cost include S&A and Contingency

8 Webbers Falls Modifications Major Modifications to date- New Upper Shafts- $1.6 Million Replace low speed gears and Pinions- $5.5 Million Paint Blades and Wicket Gates- $300,000 Stay Vane Repair, 3 Units (est)- $850,000 Additional Painting- $1.0 Million Machine Embedded Components- $700,000 Escalation Thru June $1.7 Million BUILDING 8 STRONG

9 Webbers Falls Turbine Rehab Sub Agreement Funding Unit 3 Unit 2 Unit 1 Sub Agreement Totals $19,500,000 $17,900,000 $17,900,000 Contracts, Executed Modifications, and S&A $18,912,000 $15,686,000 $16,748,000 Est. Remaining Escalation $125,000 1,550,000 1,827,000 Estimated Outstanding Modifications & Contingency 2,025,000 1,900,000 1,500,000 Estimated Required S&A $0 $1,650,000 1,050,000 Total Requirement $21,062,000 $20,786,000 $21,125,000 Projected Shortfall 1,562,000 2,886,000 3,225,000

10 Additional Project Sub Agreements SW00431-S138 Rewind Generators Units 1,2 & 3 = $6.0M Ongoing - $4.9M contract with Andritz SW00431-S092- Rehab Bridge Cranes - $2.62M Contract Complete SW00431-S137- Intake Gate, Bulkhead and Misc. Electrical - $4.0M Ongoing - $3.5M contract, additional $518K funded through ARRA.

11 Pending Sub Agreements/modifications SW00431-M001 Replace Upper Shaft Unit 1. Cost = $800,000 Status Sub-agreement sent to SWD. Replace the Low Speed Gear and Pinions Unit 1. Cost - $5,500,000 Status Sent to SWPA May 8. Replace Upper Shaft Unit 2. Cost = $800,000 Status Awaiting Draft Sub-agreement from SWPA.

12 Pending Sub Agreements/modifications Supplemental Funding for Unit 3 Cost - $1,600,000 Status Approved by the Customer Council Supplemental Funding for Unit 1 Cost - $3,300,000 Status Awaiting Customer Council Approval Supplemental Funding for Unit 2 Cost - $2,900,000 Status Awaiting Customer Council Approval

13 Projected Schedule WF Contract Req. Completion: 4 Oct Pending mods will push CRC to approx 26 Feb 2013 OZ Contract Req. Completion: April 20, Projected mods will push CRC to approx 19 Jul 2014 Work on two units simultaneously at Ozark has reduced the total contract time by three years. Potential opportunities to reduce project completion date by 1 year at each site by early turnover of OZ U5 and WF U2 as shown in the above schedule (requires customer approval). Performing stay vane crack repair concurrent with disassembly saves from 2-3 months per unit. Disassembly of the turbine has been reduced from 4.5 months (WF Unit 3) to 2.5 months (WF Unit 1 and OZ Unit 3). In-place machining of embedded wicket gate assembly mounting flanges has reduced wicket gate filing time by 6 weeks per unit.

14 Schedule Cont. Each successive unit will have a reduced duration through application of lessons learned, utilization of the schedule, and better visibility of potential differing site conditions as shown below in order of completion at each plant. Ozark OZ Unit 4 required approximately 56 months through completion of 72 hour test OZ Unit 2 will take approximately 43 months through completion of 72 hour test OZ Unit 3 will take approximately 27 months through completion of 72 hour test OZ Unit 1 will take approximately 20 months through completion of 72 hour test OZ Unit 5 will take approximately 21 months through completion of 72 hour test (includes additional speed increaser work not included on other units) Webbers Falls WF Unit 3 required approximately 43 months through completion of 72 hour test WF Unit 1 will take approximately 23 months through completion of 72 hour test WF Unit 2 will take approximately 20 months through completion of 72 hour test

15 Webbers Falls Unit 1 Speed Increaser A chipped tooth on a low speed pinion and multiple cracks on the low speed gear were found during inspection of the speed increaser. Deficiencies required replacement of the low speed gear set. Replacement occurred off of the critical path so no additional time was added to the contract.

16 Contract was modified to add a vinyl paint coating system to the series 400 stainless steel. First three units were painted after installation but remaining unit components will be painted off site to remove this work from the critical path. Corrosion The cathodic protection system is being recommissioned following the completion of painting. Adjustments to the protection potential will continue until corrosion is stopped. Changes to WF Unit 3 have shown much improved protection.

17 Stay Vane Crack Repair Performing stay vane crack repair concurrent with disassembly saves from 2-3 months per unit.

18 Improve Method of Scrapping Old Runner Improved process for removal of runner has reduced this activity duration from 4 weeks per unit to 1 day per unit.

19 Remove Wicket Gate Assembly Before Lower Shaft Initial units were disassembled with the lower shaft being removed prior to the wicket gate assembly. Due to the long duration to repair and reassemble the wicket gate assembly the removal of the assembly is now being accomplished prior to removal of the lower shaft which allows more time for the repair process on these components.

20 Machining Embedded Flanges Machining the embedded gate barrel mounting flanges reduced the wicket gate filing time by 6 weeks per unit.

21 Wicket Gate filing Initial units required the governor to be operational prior to start of wicket gate filing making this a critical path activity. Contractor is now utilizing a portable hydraulic power unit allowing the gates to be filed prior to completion of the governor. This allows the wicket gate filing to be removed from the critical path which reduced the unit duration by 6 weeks.

22 Goals Reduce installation time for each successive unit. Limit turnover of personnel. Resolve non-controversial outstanding issues, Ozark Unit 4 and Webbers Falls Unit 3. Resolve controversial outstanding issues, corrosion repair and wicket gate filing. Maintain outstanding partnering relationship.

23 Key Challenges Timely response and negotiation of RFPs. Resolution of Cathodic Protection System issues. Resolution of Oil Head Design issues. Proposal for new governors at Ozark. Removing silt from Ozark Unit 1. Rewind Webbers Unit 1 generator. Contracting for new gears for Ozark Unit 5 speed increaser. Improving communications between Operations, E&C construction office, and contractor.