Mu2e WGM

1. Mu2e WGM 1/19/2011 R. Ray Mu2e Project manager

2. Outline • Director’s Pre-CD-1 Readiness Review • Schedule to CD-1 • Funding • Pbar shielding • AD resources R. Ray - Mu2e WGM

3. Director’s Pre-CD-1 Readiness Review Review held Nov. 17, 2010 R. Ray - Mu2e WGM

4. Director’s Pre-CD-1 Readiness Review R. Ray - Mu2e WGM

5. Director’s Pre-CD-1 Readiness Review Charge Questions R. Ray - Mu2e WGM

6. Director’s Pre-CD-1 Readiness Review Recommendations (Mu2e-doc-1198) • 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. • Finalize the NEPA determination as soon as possible, preferably before the CD-1 IPR. • Proceed expeditiously filling the Deputy Project Manager position with the goal of having the person in place well before the CD-1 review. • 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. • 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. R. Ray - Mu2e WGM

7. Director’s Pre-CD-1 Readiness Review • 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. • Finalize the CD-1 resource loaded schedule as soon as practicable but no later than the end of March 2011. • 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. R. Ray - Mu2e WGM

8. Director’s Pre-CD-1 Readiness Review Mu2e-doc-1301 R. Ray - Mu2e WGM

9. Director’s Pre-CD-1 Readiness Review R. Ray - Mu2e WGM

10. New schedule to CD-1 New Schedule to CD-1 Green = completed Red = Date from Review Team R. Ray - Mu2e WGM

11. 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. R. Ray - Mu2e WGM

12. 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) R. Ray - Mu2e WGM

13. 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. R. Ray - Mu2e WGM

14. Skyshine Based on measurements of the neutron spectrum and in order to be conservative, we use the 100 MeV results R. Ray - Mu2e WGM

15. 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 10-4mrem/s, similar to the dose from skyshine. R. Ray - Mu2e WGM

16. 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 R. Ray - Mu2e WGM

17. 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 level • e.g., 2% to 5% normal losses anticipated at Debuncher extraction septum • Losses due to RF manipulations and transfer locations are hard to estimate at this time R. Ray - Mu2e WGM

18. Dose rates • (1 x 10-4 mrem/s)(0.01)(3600) = 3.6 x 10-3mrem/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 107s of running per year the highrise would see 20 mrem/year from skyshine. • Again, real problem 5 – 10 times worse. R. Ray - Mu2e WGM

19. Solution There is a solution. It just costs money… R. Ray - Mu2e WGM 19

20. Service Buildings Service building tunnel Available Shielding Region – 10’ Gravel has natural voids and low H2O content Gravel was simple to install (free-flowing) R. Ray - Mu2e WGM

21. Service Buildings R. Ray - Mu2e WGM

22. Shielding Solution R. Ray - Mu2e WGM

23. How much can we improve? • 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 R. Ray - Mu2e WGM

24. 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 R. Ray - Mu2e WGM

25. 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. R. Ray - Mu2e WGM

26. 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. R. Ray - Mu2e WGM

27. Requirements R. Ray - Mu2e WGM

28. 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 R. Ray - Mu2e WGM