Minutes of the Delphi Technical Panel, 8 June 2000.
1. Status of the Dismantling planning
- Christian presented the planning of the dismantling:
- The cavern should be empty by 1/6/2001.
- Detector groups are responsible for their detector and equipment.
- Delphi will provide support.
- Gas systems/electronics/computers will be handled separately.
- A lot of useful information is kept up to date on the web:
- Logistics and organisation:
- Logistics is complicated by the lack of storage space on-site.
- All material from the cavern should be transported off-site as soon as possible, big
items will transit through a "Central cutting zone" (common to all
experiments).
- The dismantling will be a collaboration of sub-detector staff with a general support
team (technicians, crane-drivers, ...).
- The dismantling will be coordinated by a small central group (Christian, Georg, Jean,
Bernard) in collaboration with sub-detector responsibles.
- During the dismantling there will be at least one meeting per week. Technical
responsibles of detector groups have to be present 1 week before and during their
dismantling task.
- INB questions:
- Delphi will be considered as 'conventional waste'. Except for VSAT.
- All components/containers will be checked for radioactivity before leaving the site.
- However, Delphi is sharing the site with an INB installation (LEP): materials should be
strictly separated and in principle there is no passage between LEP and Delphi cavern.
- Gas systems:
- Dismantling is handled by the gas group.
- The SG building will be used to store HPC modules end extract sources.
- Sale and Re-use:
- Tenders are out, responses are received. 2 offers end with positive sum.
- Sale is handled by SPL division and material is considered CERN property. Any income
will flow back to DELPHI team account.
- No official requests for re-use are received, but inofficial interest (by CosmoLHC) is
expressed to re-use MUB, HOF, MUF and TOF. However re-use might have impact on the
dismantling procedure (eg. extra manpower).
- The expo in the SX hall should be dimantled in september and pieces are to be
recuperated by the detector groups.
- Anybody intersted in the "clean tent" in SX should contact Christian
asap.
- The remaining poins of worry are:
- The tight schedule in removing the HPC modules and the removal of their sources
afterwards.
- The lack of storage space for the TPC before extraction of its sources.
- Christian announced the publication on the web of the "
Dismantling Project Report" and invited evrybody to have a look at it and give
feedback.
- Stefano shared the worries on planning and manpower on the dimantling of the HPC. He
also inquired on not mentoning the lead of the HPC as such.
- Christian agreed the planning is thight, but it should be feasible.
- The lead of the HPC is marked as 'composite' material and will be sold as such;
the cost of separating the lead from the rest of the HPC would not outweight the extra
income.
- On a remark from Alberto, it was stated that the lead of the TAG are marked as 'clean'
lead, and not as composite.
- Gerald and Jacques expressed their worries as to what would happen with the MUB and MUF
in case CosmoLHC would not take place.
- It should be made very clear that once taken, CosmoLHC should be responsible for
disposing of the detectors; they can not fall back on Delphi again. Property of these
detectors should be properly tranferred to CERN-EP.
- It was also stated that CosmoLHC is mainly interested in MUB and only to a lesser extend
in MUF (that operates with a flammable gas mixture).
2. Safety during the DELPHI dismantling
- Georg presented safety issues during the dismantling.
- Applicable documents are 'SAPOCO42' and Safety Note NS20.
- The glimos is responsible for safety during the dismantling, with safety linkman on-site
(Jean and Bernard) acting as immediate supervisor of ALL persons working in the pit.
- Access to the dimantling zone (essentially the whole Delphi site) is for authorized
persons only. As a general rule NO visits will be allowed.
- Preparation
- tools for dismantling should be tested.
- All persons working in the pit should provide their own (safety) equipment to work in
the pit (like helmets, gloves, etc.).
- Before dismantling, flammable gas will be purged, solenoid will be demagnetised, water
circuits will be stopped and emptied, power will be disconnected (to detector and counting
rooms). Scaffolding and platforms will be installed.
- Safety equipment
- Smoke, fire and gas detection in detector and counting rooms will be disconnected, as
well as the telephones in the counting rooms.
- Safety services in the cavern itself will remain operational.
- Protection of persons
- All persons working in the underground area should have UX-clearance.
- The CERN fire brigade gives a 3 hr safety briefing every week on working in underground
areas.
- The GLIMOS will give information on Delphi specific safety issues.
- It is obligatory to wear helmet and safety shoes during dismantling activities.
- Georg stated that there are no additional special courses at the fire brigade, but they
are held every week. Detector groups are encouraged to prepare themselves in advance and
send staff likely to work underground to these courses in due time, and not to wait till
the last moment.
- On a remark of Alberto to have a video-taped safety course, it was mentioned that this
would not be very practical, and probably not accepted by CERN. This UX-clearance is a
CERN rule, not specific to DELPHI.
- Georg confirmed a remark from John that filmbadges would still be needed also during
dismantling. Detector groups should prepare this as well for staff not already having such
a filmbadge.
- Christian encouraged people having to work downstairs to follow a first-aid course.
3. Electronics and online cluster
- Philippe presented strategies on removal of electronics from the pit and the future of
the online cluster.
- Timescale would be the first 3 months of the dismantling, minimising the interference
with detector dismantling.
- Central electronics and SlowControl electronics will be handled by a central team
(coordinated by Yvon and André).
- After that detector groups are invited to recuperate their fastbus electronics and other
equipment (camac, nim, lab equipment etc.). Not only from the pit, but also from SX labs
(above control room).
- All equipment leaving the pit should be checked against a 'EP pool inventory'
(done by central team).
- All EP-pool equipment will be returned to the pool by the central team, detector groups
are responsible of shipping their equipment.
- Remaining problem is to locate all EP-pool equipment not at Delphi site. Should be
located and returned to the EP-pool or offically transferred to new user.
- All relevant information on planning etc. will be published and kept up to date on the
Web.
- The online cluster:
- The cluster will remain operational until CERN christmas closure.
- The cluster will be re-installed in building 13 in January 2001.
- At any moment detector groups can request removal of their detector workstation.
- Detector enquiry
- A questionnaire will be send to the detectors to get an idea of re-use of electronics
and future needs of the online cluster.
- On a question of Philippe C. concerning possible extension of this years running,
Christian remarked that this should be decided rather soon, since contracts are about to
be signed now. In case of extension, 3 months notice would be the minimum.
André Augustinus, 19-jun-2000