The Cryopit

1. TheCryopit Fraser DuncanCryopit Workshop16 August 2011

2. Underground Campus Cube Hall Cryopit J-Drift HALO Stub Ladder Labs SNO Cavern South Drift Personnel facilities Utility Area Fraser Duncan Cryopit Workshop 16 Aug 2011

3. Cryopit Fraser Duncan Cryopit Workshop 16 Aug 2011

4. SNOLAB, an expansion of the original SNO laboratory, was proposed by the original SNO Canadian universities (Carleton, Guelph, Laurentian, Queen's and UBC) and University of Montreal with Carleton University as the Lead institution. The project was divided into Phase I (Cube Hall, Ladder Labs, new lab entrance) and Phase II (the Cryopit) to provide a break point to control project cost. The Cryopit, at $16M, was an addition to the initial SNOLAB grant and was funded 50% from federal and 50% from provincial contributions. It was conceived as a hall that could readily be isolated from the rest of the underground facility in the case that it contained a large inventory of cryogens or other substances that could displace significant volumes of air. Excavation began in 2007 and was completed in 2008. Was brought to a clean room state in March 2011. Third largest cavity after the SNO Cavern and Cube Hall (about 1/3 the size of the SNO Cavern). History Fraser Duncan Cryopit Workshop 16 Aug 2011

5. Cryopit Cube Hall BAR (Bottom Access Drift) STAC (Staging Area Cryopit) Notches for Pressure Bulkheads Bottom Access Ramp Airlock J-Drift TAC (Top Access Cryopit) Fraser Duncan Cryopit Workshop 16 Aug 2011

6. Limited “As Built” Surveys have been Done Fraser Duncan Cryopit Workshop 16 Aug 2011

7. The Cryopit

8. Cryopit

9. STAC (Staging Area Cryopit)

10. STAC (Staging Area Cryopit)

11. Cryopit Utility Drift (J-2 Drift)

12. TAC (Top Access Cryopit)

13. Bottom Access Drift

14. Bottom Access Ramp Airlock

15. The Cyropit is designed to be operated at a higher air pressure than the surrounding areas to force dust out. The air is recirculated through HEPA filters. Particulate measurements are done on a regular basis. With no work being done in the Cryopit, achieving much better than the class 2000 goal. Cleanliness Fraser Duncan Cryopit Workshop 16 Aug 2011

16. Present: Ventilation: Nominally 5 air changes/hr through HEPA filtered, cooled air. Fire Water and Chilled Water (also available for process equipment). Future: Power: Design is for a 400 A service at 600 V phase with a Motor Control Centre located south of the Cryopit. Communications: Tie in to existing fibre network. Fire Detection: Detection and alarming contract issued and should be complete by year end. Plumbing: Industrial Water, Ultra Pure Water, Forced Drain, Compressed Air. Services Fraser Duncan Cryopit Workshop 16 Aug 2011

17. Safe venting in the case of cryogenic boil off or other release of inert gas. 1200 ft (370m) run from Cryopit to sealed exhaust raise. Possibly install pressure bulkheads around the cryopit. Need to coordinate with other experiments also planning to use vent raise. Exhaust Venting Fraser Duncan MC Collab Mtg Yale 19-21 July 2011

18. Cryopit Configuration Options Fraser Duncan Cryopit Workshop 16 Aug 2011

19. Option: Stand Alone Tank Fraser Duncan Cryopit Workshop 16 Aug 2011

20. Option: Spray on Liner Fraser Duncan Cryopit Workshop 16 Aug 2011

21. Option: Small Tank and Deck Fraser Duncan Cryopit Workshop 16 Aug 2011

22. The Cryopit has been a 3,900 m3 class 2000 clean room since May 2011. Beneficial occupancy could occur Jan 2011 with completion of fire detection. Electrical infrastructure would also need to be installed. Could deploy a short term experiment almost immediately by constructing a small tank and deck. Fully exploiting the cavity would (likely) require design and installation of large deck and liner/tank. Summary Fraser Duncan Cryopit Workshop 16 Aug 2011

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