Mu2e WGM

1/19/2011

R. RayMu2e Project manager

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Outline

• Director’s Pre-CD-1 Readiness Review• Schedule to CD-1• Funding• Pbar shielding• AD resources

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Director’s Pre-CD-1 Readiness Review

Review held Nov. 17, 2010

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Director’s Pre-CD-1 Readiness Review

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Director’s Pre-CD-1 Readiness Review

Charge Questions

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Director’s Pre-CD-1 Readiness Review

1. Prepare a detailed list of milestones and specific deliverable dates (exact day) in support of a successful CD-1 review in June 2011 -- by the end of this month.

2. Finalize the NEPA determination as soon as possible, preferably before the CD-1 IPR.

3. Proceed expeditiously filling the Deputy Project Manager position with the goal of having the person in place well before the CD-1 review.

4. Secure firm commitments, in writing, for increasing the time devoted to Mu2e by staff already assigned to the project that are expected to ramp-up effort – within the next three months.

5. Fill additional open positions, including the risk manager, and secure additional mechanical engineering support at FNAL in time for the Director’s review of CD-1 readiness. Project Controls staffing should continue to ramp up near CD-1 in preparation for CD-2.

Recommendations (Mu2e-doc-1198)

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Director’s Pre-CD-1 Readiness Review

6. Start creating your Bases of Estimate documentation now and assign a person to be responsible for tracking the development and ensure consistency of the information.

7. Finalize the CD-1 resource loaded schedule as soon as practicable but no later than the end of March 2011.

8. Develop a sound plan on how Mu2e will get from CD-1 to CD-2, to be presented at the CD-1 review. This plan needs to address any additional resource needs and how the project is going to acquire them.

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Director’s Pre-CD-1 Readiness Review

Mu2e-doc-1301

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Director’s Pre-CD-1 Readiness Review

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New Schedule to CD-1Milestone Who Date

DOE CD-1 Review May 31, 2011

Director’s CD-1 Review May 3, 2011

CDR complete Project Office April 4, 2011

RLS Complete – Cost and Schedule ranges set. Project Office March 31, 2011

Collaboration comments incorporated into CDR Project Office March 28, 2011

CDR comment period concluded March 21, 2011

Project document cleanup Project Office March 11, 2011

Director’s Design Review March 1, 2011

Release CDR to Collaboration March 1, 2011

CDR Complete except for RLS Project Office Feb. 25, 2011

Basis of estimates complete L2s Jan. 31, 2011

Resource estimates complete L2s Jan. 24, 2011

L2 CDR chapters submitted to PM L2s Jan. 17, 2011

L2 Design Reviews complete L2s Jan. 14, 2011

Resources identified for each task L2s Jan. 10, 2011

Review and rank risks L2s Dec. 17, 2011

Milestone Tiers complete Project Office Dec. 17, 2011

Milestone dictionary complete L2s Dec. 13, 2010

L2 Milestones identified L2s Dec. 13, 2010

Task logic completed L2s Dec. 6, 2010

Task durations complete L2s Dec. 6, 2010

L2 tasks complete L2s Dec. 6, 2010

Pre CD-1 Readiness Assessment Nov. 17, 2010

Green = completedRed = Date from Review Team

New schedule to CD-1

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Pbar Ring Shielding

• We have always known that the shielding of the pbar service buildings was an issue at 25 kW. We did not know the magnitude of the problem until recently when Don Cossairt completed a calculation of prompt radiation levels and skyshine for 25 kW operation.

• Don’s estimates show that the 3 poorly shielded access buildings around the pbar ring pose a significant problem.

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Measurements

• The basis for these estimates are a set of measurements made in 2000 using reverse protons.

• Turn off Lambertson Localized, well understood

loss of entire 8 GeV beam.• 5 chipmunks deployed on

floor of service building directly above beamline.

• The measured dose rate above AP-30, scaled to 25 kW, is 12.6 mrem/s.

(12.8 Watts)

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Skyshine

• Established methodology for skyshine calculations.

• Term in ( ) is a build up factor that describes the observed scattering of neutrons in air back towards the ground.

• l can be thought of as an approximate mean free path and is energy dependent.

dHeff (r)dt

aAs

dHeff

dt s

4r2 1 e r / e r /l

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Skyshine

10-8

10-7

10-6

10-5

0.0001

0.001

0.01

0.1

1

0 200 400 600 800 1000

Skyshine Estimate

1000 MeV400 MeV200 MeV100 MeV40 MeV20 MeV10 MeV4 MeV2 MeV1 MeV

dHef

f/dt (

mre

m s

-1)

r (meters)

BoosterTowers

Wilson HallLederman Center

Site Boundary

Based on measurements of the neutron spectrum and in order to be conservative, we use the 100 MeV results

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Direct Radiation

• Upper floors of the highrise look directly at the source and see direct radiation as well as skyshine.

• Wilson hall is 460 m away, 73 m tall and sees 16% of emitted neutrons based on solid angle.

• The estimated direct prompt radiation dose at the top of Wilson Hall is ~1.2 x 10-4 mrem/s, similar to the dose from skyshine.

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DOE and Fermilab Limits

• DOE exposure limit for the public is 100 mrem/year• DOE reporting limit is 10 mrem/year.• Fermilab de facto limit is 10 mrem/year

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Normal Running Conditions

• We have evaluated accident conditions and normal running conditions.

• Normal running conditions provide the tightest constraint.• Cossairt assumes a 1% beam loss spread among three service

buildings At significant distance, sources just additive Inconceivable that we can achieve/maintain this very low loss

levelo e.g., 2% to 5% normal losses anticipated at Debuncher

extraction septumo Losses due to RF manipulations and transfer locations are

hard to estimate at this time

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Dose rates

• (1 x 10-4 mrem/s)(0.01)(3600) = 3.6 x 10-3 mrem/hr.

• Reach 10 mrem/year limit in 2800 hours of operation.

Real problem is up to 10 times worse (1% loss 5% loss plus direct radiation at the top of Wilson Hall)

• Put another way, for 1% continuous losses, for 2 x 107 s of running per year the highrise would see 20 mrem/year from skyshine.

Again, real problem 5 – 10 times worse.

10-8

10-7

10-6

10-5

0.0001

0.001

0.01

0.1

1

0 200 400 600 800 1000

Skyshine Estimate

1000 MeV400 MeV200 MeV100 MeV40 MeV20 MeV10 MeV4 MeV2 MeV1 MeV

dHef

f/dt (

mre

m s

-1)

r (meters)

BoosterTowers

Wilson HallLederman Center

Site Boundary

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Solution

There is a solution. It just costs money…

19

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Service Buildings

tunnel

Service building

AvailableShielding

Region – 10’Gravel has

natural voids andlow H2O content

Gravel wassimple to install(free-flowing)

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Service Buildings

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Shielding Solution

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How much can we improve?Type Gravel

(70% packing efficiency)

Taconite (70%

packing efficiency)

Plate steel Concrete Effective shield

thickness

Heff mrem/s@25KW

Existing 7’ 1.5’ 7’ 12.56

All concrete

10’ 10’ 1.26

*Taconite & concrete

3’ 7’ 13’ 0.126

*Plate steel plus concrete

3’ 7’ 16’ 0.0126

• Booster has 14 feet of shielding, operates at higher power and is closer to the highrise.

• Local soft spots at 12 foot intervals due to concrete beams• Working with Nikolai to get MARS running to confirm shielding effectiveness of

various materials

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Remaining Issues

• Stairways require separate analysis New measurements made 3 weeks ago. Have to determine appropriate QF Will have to control access to buildings during running. Looking at contribution to skyshine. Should be OK.

• 500 + penetrations at three service buildings Low energy neutrons rather than high energy neutrons Many can be filled in after removal of stochastic cooling Represent small area

• Final in-tunnel supplemental shielding Local shielding around known hot spots

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Cost and Schedule

• Tom’s “gut feel” is about $3M per building.• I put a contingency of 100% on gut feel cost estimates.• Work can be accomplished in a year.

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Accelerator Division Resources

• We need engineering help in determining cost, resources, and duration for the various sub-projects.

• OECM will co-chair a separate cost review session of the CD-1 Review with Lehman. We have to have documentation in place that supports our cost range.

• We need 1 - 2 weeks from engineers with relevant experience in: Rings and Transport to Rings Rings RF Extraction External Beamline Target Station AC dipole

• We understand that these people are not currently free and are all busy working on other projects. We are asking that they be pulled off of those other projects for 1 – 2 weeks to help us get to CD-1.

This is how matrix management is supposed to work. Steve will discuss this request in detail next.

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Requirements

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Action Items

• Project EE – Ron Ray Done

• Complete set of requirements documents – Miller/Bernstein Still not complete.

• Start scheduling internal L2 design reviews Done. Reviews have been completed.

• Develop a plan for Directors Design Review and Pre-CD-1 Review Done