CERN ATOMTEX BDKG-24, Manual

Page: 44 / 93

REFERENCE EDMS NO. REV. VALIDITY
TOF-TAR-PRD-0001 1867100 1.0 RELEASED
Page 44 of 93
HSE-RP comments:
Depending on water contamination level (to be
verified by RP), the possibility to use the spare
cartridge to further filter the water before the target
removal and cooling station dismantling should be
considered. The possibility to reduce the radiological
risks during the intervention should be weighed
against the resulting additional waste produced by
this action. Expert should provide a
recommendation on the benefit of this action. The
spare cartridge was partially filled right after its
installation with water from the circuit but was
never used online.
Name of task
330. Drain upper
section of pipes from
the cooling station
Exposed people
Local dose rate 10 µSv/hr
Workforce
Time needed ?
Calculated dose
Responsible EN-CV
Involved EN-CV/ EN-EA/ EN-HE/
HSE-RP
Comments:
Initial pumping/sucking can be done in the cooling
station away from the target.
Water needs to be sucked/pumped out at different
heights to remove as much water as possible.
Planned Procedure:
1) Pressurise circuit and push water out of
circuit using air (should drain 1/2 of circuit)
2) Allow water to settle again and then insert
a tube down the pipes to suck out water
remaining in the top section (above the
main joint)
. If a tube can’t be inserted all
the way through the corners in the tube,
the tube may be drilled half-way in order
to gain access.
Moderator circuit must be drained first to prevent
the target’s window from breaking and the two
circuits mixing. The window will withstand the
pressure of the full water column (8.5 m) as long
as the pressure is from the cooling to the
moderating side (EDMS docs 934369 and 953823).
A manual winch will be needed to recover persons
in the case of an emergency.
A mock-up has been made to test this
procedure.
This task will be developed further and by
EN-CV.
All of the pipes from the cooling station to the
target are waste, they will not be reused. They will
be removed in a later task.