Under RV Head Inspections & Decon

[imbucky]

Point Beach Spring Outage 2004

This outage that we are currently in is the 4th time we've done underhead decon and RV head inspections.

We have had Framatome (now currently Areva) do all of the inspection work.

From an RP standpoint we have had great relations with this company. Great communication and people skills all around from these guys.

We have a fairly small RV head and we set it in a LDA 2 floors down from the refuel floor on head stands. For inspection purposes we put extensions on the head stand so it sits about 5 ft off the floor.

Before the head is put in the LDA we build a shield ring and have a flat inspection floor put in place. This is needed because the floor is slopped to a drain right in the middle of the LDA and Framatome inspection equipment requires a flat floor for the inspection robot (Called SUMO ROCKY)
Once the head is lowered we perform a underhead decon with 3000 psi pressure washers to remove boron and ga dose.

We've learned a lot since our first attempt at inspections. The first time we used herculite and covered the lead and drapped it to the floor drain. Then when we deconned the water leaked into the basement of containment. HRA buckets of water...not good.

The following outage we purchased a swimming pool liner and used that like a giant drip catch cutting a hole to access and a hole for the drain. Worked great and we still fine tuned it. 
This last outage we dropped out GA dose rates from 10 R/hr contact with the top of the dome to 4.5 R/hr contact top of the dome after the decon. This had also been what we had accomplished the last outage. Deconning roughly dropped the dose in half by doing the decon.
Another benefit it that Framatome equipment probes last much longer without rubbing abainst the boron under there. Boron acts like sandpaper in tight places.
Normally the contam levels are high, something that Point Beach isn't use to seeing. This outage our contam levels are hanging really low, aroung 10k GA in the work area and slightly higher under the head.
If anyone needs more info on this feel free to contact me and maybe we can give some OE from what we've learned?

Good Luck.........Bucky

[imbucky]

Oh yea....forgot to mention that we also have done some gringing and welding activities in the past if anyone needs more info on that?

[South_African]

We did head inspection also using Framatome - however I guess we never thought of deconning under the head. Sure would like to hear more on how you did it and more on the dose saving.