JAEA-Testing-2011-007.pdf:46.74MB - 日本原子力研究開発機構

JAEA-Testing 2011-007
JAEA-Testing 2011-007
(5) Discharge the supernatant, while leaving the precipitate
Discharge the water in the plastic tank when it meets the criteria for discharge
with respect to radioactivity concentration and pH.
In accordance with the section 4.(2)(a), remove mud and fallen leaves accumulated
in the discharge flow path such as drain gutter around the swimming pool and
foot washing pond to discharge water compliant to the criteria.
Put collected mud and fallen leaves into plastic bags with a serial number. The
mouth of the bags shall be twisted, folded back and closed with a banding band.
The bags shall be put into additional plastic bags, forming a double packing. The
outer bags shall also be twisted, folded back and closed with a banding band.
Measure the dose rates of each bag at the surface using a radiation detector. If
possible, weigh the bag (weight by the kilogram is acceptable). Write down the
results in the form, “Record 7: Dose rate measured on the surface of bags that
contains mud accumulated at the discharge flow path”.
Use medium capacity engine pumps for the discharge. Take care to pump up as
little precipitate as possible, and discharge it through a bag filter.
Pumping the supernatant Bag filter Filtrated water with the
bag filter
(6) Treat the precipitate left on the bottom of the 1 ton plastic tanks
Apply filtering to the precipitate to remove water as much as possible for disposal.
Pump up precipitate accumulated on the bottom of the 1 ton plastic tanks with a
small capacity engine pump into a container covered with a sheet (or basket) at a
low flow rate. Prepare two sets of tray to receive the filtrated water and a
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