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Civil Construction in the US Chris Laughton, Fermilab

Civil Construction in the US Chris Laughton, Fermilab. Outline. Sites Under Consideration West Coast Midwest Scope Cost & Schedule Contingency Next Steps. Sites Under Consideration. West Coast Diablo Canyon* Midwest Braidwood*

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Civil Construction in the US Chris Laughton, Fermilab

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  1. Civil Construction in the US Chris Laughton, Fermilab Theta 13 San Luis Obispo Workshop

  2. Outline • Sites Under Consideration • West Coast • Midwest • Scope • Cost & Schedule • Contingency • Next Steps Theta 13 San Luis Obispo Workshop

  3. Sites Under Consideration • West Coast • Diablo Canyon* • Midwest • Braidwood* • Byron ~ overburden requirements would place detector halls in weak sandstone. Dolomite and sandstone tunnels would be below the water table. • LaSalle ~ similar site conditions to Braidwood. • Wolf Creek ~ sited in shales and limestones. Diablo Canyon-Type Portal Entrance * Scoped and Estimated Theta 13 San Luis Obispo Workshop

  4. Braidwood 2 Vertical Shafts - 10m Ø & 120m deep 1 Tunnel - 300m long 8m span horseshoe tunnel. Uniform 1% tunnel gradient to shaft. Firewall-Isolated Excavations accessed from the Running Tunnel/Shafts 3 Detector Rooms 1 x Near Detector Room - 32 m long 12 m span 2 x Far Detector Rooms with 8 m span access tunnels - 16 m long x 12 m span 1 Underground Emergency Refuge (at end of tunnel) 6 m long 4m span separately ventilation 2-hour fire rated wall Utility/Sump Room 4 m horseshoe nominal 8m length Diablo Canyon 1 Portal Entrance -10 m long 1 Tunnel - 850m long 6m span horseshoe tunnel. Uniform 1% tunnel gradient to portal. Firewall-Isolated Excavations accessed from the Running Tunnel 2 Detector Rooms 2 x 40m long 10m span chambers 1 Underground Emergency Refuge Nominal 6 m long 4m span Equipped with 2-hour fire rated wall and self-rescuers Scope Underground Construction Theta 13 San Luis Obispo Workshop

  5. Single continuous concrete floor Hilman roller rails embedded (except in refuge) Cable Trays Pipe Stands Utilities in place at beneficial occupancy at both sites light string, ventilation ducting and fans refuge firewall At Braidwood Flood barrier at Far Detector site (1 m high concrete blocks) Pumps (Goodman quote) Elevators (Alimak quote) Scope“Finish-Out” - Similar for Both Sites Shotcrete Finish Walls & Crown Theta 13 San Luis Obispo Workshop

  6. Braidwood Soils ~ 20 m of saturated soils Rock (Various Units) Coal measure strata Limestone with shale (NuMI - Fort Atkinson) Shale (NuMI - Scales) Galena Platteville (Dolomitic Limestone or Dolostone) Notable question marks relating to: Deep water table elevation? In situ stress levels? Swelling potential of rock units containing clay minerals? Etc.. Diablo Canyon Minimal Soil/Weathered Rock Rock (Mainly Dolomitic Sandstone) Heavily deformed geologic structure (folded/faulted) Inter/Intra-bedded volcanic sills (altered basalt, tuffs..) Surface rock samples have tested to ~ “high strength” Thin chert stringers present (highly abrasive micro-silica) Notable question marks relating too: Structure at depth- what’s where? Abrasive cherts - roadheader impact Blocky rock behavior at depth Altered basalt behavior at depth Etc.. Scope Ground Conditions(assumptions pending site investigation) Theta 13 San Luis Obispo Workshop

  7. Braidwood Drill and Blast appears to be the preferred excavation method - short tunnels of varying cross-sections sited in relatively strong rock units Permanent Tunnel/Room Support Rock Bolts Reinforced Shotcrete Permanent Shaft Support provided by cast-in-place concrete lining Diablo Canyon Drill and Blast used for initial estimate - based on high strengths of surface-gathered samples (Viability of mechanical excavation will be reviewed after a modicum of site investigation has been performed) Permanent Tunnel/Room Support Rock Bolts, Lattice Girders Reinforced Shotcrete ScopeExcavation Methods & Means Shotcrete Scoop Tram Drill Rig Theta 13 San Luis Obispo Workshop

  8. Cost & ScheduleThe Estimating Process • Proposal should be based on a reliable cost estimate. • “The only kind of estimate that is worth anything is the one that is clearly defined on paper and bears the signature of the author.” J.S.Redpath, (1980). Theta 13 has underground estimates that are: • Well-documented and site-specific - developed “from the bottom up” • Estimated independently by an experienced, tunneling professional. • Reviewed independently by experienced, tunneling professionals. • Underground estimate scopes include: • Underground Structural Shell and Utilities • Utilities left in place (power, ventilation, water, air lines, communication..). • Permanent facilities installed (groundwater pumps, elevators and refuge firewall, surface water treatment facilities). • Estimates exclude: • Engineering, Design, Inspection and Administration (EDIA), Surface Buildings, Technical Installations, Life Cycle Costs Theta 13 San Luis Obispo Workshop

  9. Cost & Schedule Aims of the Estimating Process • Objectives • Reduce uncertainty in cost/schedule data collected/reported in early work. • Deliver a schedule and estimate by Mid-March. • Outcome • Consulted directly with tunnel estimators to obtain site-specific products, that met the deadlines at a relatively low unit cost: • ~ $10k Tunnel Cost Estimating Consultants (Hilton, Sperry & Wightman) vs. • ~ $15-20k Outside Tunnel Design Companies (CNA, HMM & Jacobs Ass.) & • ~ $40k In-House Engineering Group • Established Solid Basis for Future Planning • Experimental scoping and proposal development • Reviews (Constructability, Value Engineering, Contract Strategies) • Site investigation work • Minimize potential for claims of “low-balling” - that may have surfaced if “ball-park” numbers had been used • Cost better understood -> Can plan with more confidence Theta 13 San Luis Obispo Workshop

  10. Cost & Schedule Review of the Unit Cost Data Sets • Sources: tunnel contractors, designers and consultants • Re-sorted for sub-horizontal, 4 - 8m span rock tunnels • Mined in last ten years by TBM, D&B or RH methodology • Hard abrasive or very soft host rocks eliminated • Cost “as reported/quoted” as a final cost per linear distance (auxiliary structures included) • Wide Range of unit costs $3k to $12k/linear foot • Average of 27 case histories ~ $5k/linear foot • Lowest unit costs in longer TBM tunnels (uniform mining/ground conditions/”good” TBM-systems, ref. Fermilab-Robbins R&D) • Highest unit costs in shorter drill and blast/roadheader tunnels (variable mining/ground conditions poor systems) Theta 13 San Luis Obispo Workshop

  11. Cost & Schedule Need for a Site-Specific Estimate • Wide range in unit prices underlines need for a site-specific estimate • Costs ƒ(wage rates, craft skills, craft availability, infrastructure, support services, taxes, climate, local customs and methods, local support/opposition to the project, etc…) • Costs ƒ(ground conditions….) • In tunneling a trend noted towards fewer bids/less competition: • Contractors are leaving the business -> too risky • Contractors are working at full capacity -> too busy • Contractors are joint venturing -> too risky • Nowadays expect fewer bids • Unit prices are Site-Specific & Time Specific - Braidwood & Diablo Canyon unit pricing can be used for the sites but should not be used on other sites and should be checked periodically. Theta 13 San Luis Obispo Workshop

  12. Braidwood Duration 39 months “First” detector site delivered in17 or 20 months (far or near) Cost $34.6M General Mobilization ~3.3M Shafts ~ 15.9M Tunnel ~ $9.1M Detector Rooms ~ $6.0M Refuge ~$0.3M 40% contingency. Initial comments: equipment selection, crew sizing and productivity OK. Shorter shafts could use cranes. Diablo Canyon Duration 24 months Cost $23 M General Mobilization ~$2.9M Portal Cost ~$0.3M Tunnel ~ 16.5M Detector Rooms ~$3.2M Refuge ~$0.1M 30% contingency. Initial comments: equipment selection, crew sizing and productivity OK. Some relatively conservative production factors - mucking might be done more quickly. Cost & ScheduleBottoms-up Estimates’ Bottom-lines Theta 13 San Luis Obispo Workshop

  13. ContingencyUnderground Construction • Many ways for a tunnel project to go wrong (not just a issues of differing conditions!) • Make sure cost and schedule expectations are realistic at the outset and kept that way for the duration of the project. • Risks needs to be identified, mitigated and properly documented/communicated. • Even if the ground is expected to be perfect early construction contingencies need to be at least 25% range. Theta 13 San Luis Obispo Workshop

  14. ContingencyStatus of the US Proposals Basis of Estimate. Guesswork based on limited desk study of regional data sets. • Rock mass characterization, alignment and estimate assumptions are subject to review after site-specific investigation work is performed • Localized studies and site-specific investigation is a pre-requisite to support the advancement of the underground design • We do not know for sure what is there because we haven’t looked yet! • Can’t mitigate what has not yet been identified! • Contingency Allocated Theta 13 San Luis Obispo Workshop

  15. Next Steps • Site Investigation • Engineering Tasking and Organization • Reviews • Making contact with design and contracting companies who can support the engineering, reviews - individual consultants will also be of value (notably where contracting rules are challenging!). “Natural” Tunnels (Spooner’s Cove) “Man-Made” Tunnels (Neutrinos @ Main Injector) Theta 13 San Luis Obispo Workshop

  16. Braidwood (w/Exelon) Desk Studies ISGS support - others? Field Work @ Braidwood @ Other local rock/soil sites Initial Shaft Site Selection Avoid any surface and buried obstructions etc. Drilling Campaign ~ Coreholes along shaft centerlines Diablo Canyon (w/PG&E) Desk Studies LBL Earth Science Support ~ complete Field Work @ Diablo Canyon site @ Other local rock sites Initial Tunnel Site Selection Portal Location, Tunnel Alignment Drilling Campaign ~ Directional drilling ~ Seismics @ Portal Next StepsSite Investigation Theta 13 San Luis Obispo Workshop

  17. Next StepsEngineering Task Definition • Initial Organizational Steps • Site Investigation Work package(s) • Plan Engineering Tasks (Discipline:Task Matrix) • Outside Support Scope/Contractor Selection/Contracting • What can’t we do in-house? • Who do we need to help? How do we find them? • Develop some familiarity with Beavers, Groundhogs and Moles. • Contracting Strategies (risks allocation/sharing) • Design-Build (D-B) • Engineer-Procure-Construct (E-P-C) etc.. • Schedule and WBS Development • Availability of other Resources Theta 13 San Luis Obispo Workshop

  18. Next StepsReviews • Requirements Definition (underground site visits) • Make sure we are not asking for more than we need • Define “acceptable conditions” e.g. moisture/floor movement (avoid over-design & specification) • Constructability Reviews • Look for easier, practical ways of performing the work • Value Engineering Reviews • Once scope, costs and risks are well-defined investigate and estimate alternate ways of achieving the same end Theta 13 San Luis Obispo Workshop

  19. Tunnel Designers CNA* Condor Earth Technologies* Hatch Mott MacDonald* Jacobs Associates* Montgomery Watson Harza* Parsons Brinckerhoff* Parsons Engineering* URS* etc.. National Tunnel Contractors Affholder, Atkinson, Frontier-Kemper Kenny Construction, Kiewit Construction, Obayashi, Traylor Brothers, etc.. Local (Ca) Wine Cavers Alf Burtleson, California Wine Caves, Magorian, Nordby Wine Caves*, Glen Ragsdale, etc. Next StepsFind Reviewers, Designers & Builders(Beavers, Groundhogs & Moles) Partial listings * SOQ Provided/Promised Theta 13 San Luis Obispo Workshop

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