Radioactive sources disposal by sewer

We are going to attempt to dissolve some sources as per CLEAPSS instructions, and wondered if anyone else has successfully done this and any tips?? The sources are:

1) Uranyl Nitrate (x2) ~ 50g
2) Uranium Oxide ~ 5-10g

The nasty one is the Uranium Oxide as it has to be dissolved in 8M hot nitric acid!! Our chemistry technician is very proficient...just wondered if anyone else had attempted it?
 
Uranyl Nitrate which was essentially dissolved in water in small batches then flushed down the loo. The SRA was supplied by CLEAPPs. Your RPO would need to be informed/ should be made aware. I assisted with the disposal but it was done RPS who is also a chemist aswell
 
A couple of years ago I gradually disposed of our old college made Protactinium Generators and jar of Uranyl Nitrate via the sewer following CLEAPSS L93 guidance at that time. Cleapss L93 is frequently updated including this month (Nov 2019). I had about 30g of Uranyl Nitrate which we dissolved into a large 2L disposable plastic bottle (labelled etc) from which we disposed of a quarter at a time once a month.

Also we disposed via a registered waste carrier: Thorium Hydroxide powder, powder radon generators, Becquerel plates and cloud chamber sources. Luckily a few local schools combined collection to achieve a saving.
 
We are going to attempt to dissolve some sources as per CLEAPSS instructions, and wondered if anyone else has successfully done this and any tips?? The sources are:

1) Uranyl Nitrate (x2) ~ 50g
2) Uranium Oxide ~ 5-10g

The nasty one is the Uranium Oxide as it has to be dissolved in 8M hot nitric acid!! Our chemistry technician is very proficient...just wondered if anyone else had attempted it?
Yes no problem.
 

Nick Mitchener

COMMITTEE
oh what a pain, now we have to get rid of our radium source just as I put it back into service following earlier advice to retire our cobalt 60.

The good news is we abandoned protactinium generators in favour of radon decay while we were still allowed to dispose of them.
 
Cleapss have just issued a new guide L93, you will need to check this carefully as quite a lot has changed including not disposing of waste via the drain
 

Nick Mitchener

COMMITTEE
Cleapss have just issued a new guide L93, you will need to check this carefully as quite a lot has changed including not disposing of waste via the drain
Yes I am so glad we dealt with the protactinium when we did, sadly I took the advice on using the radium when we were going to get rid of it.
 

Nick Mitchener

COMMITTEE
Yes I am so glad we dealt with the protactinium when we did, sadly I took the advice on using the radium when we were going to get rid of it.
Well after studying various documents and speaking to Samir I've now supplied a picture of our radium source foil, and it may be ok to keep it.

If it isn't then the modified grout route is still open to us as we don't need to concern ourselves with the actual disposal route any more.

It's all in the guide but you have to read it very carefully to pick up the changes.

I think CLEAPSS are doing a grand job of updating advice and protecting us from the unintended consequences for education of legislation that doesn't take us into account. My only thought is it might be helpful to have a highlighted version showing the changes because the document that listed the changes did not cover all of them and was a bit light on detail.
 
Well after studying various documents and speaking to Samir I've now supplied a picture of our radium source foil, and it may be ok to keep it.

If it isn't then the modified grout route is still open to us as we don't need to concern ourselves with the actual disposal route any more.

It's all in the guide but you have to read it very carefully to pick up the changes.

I think CLEAPSS are doing a grand job of updating advice and protecting us from the unintended consequences for education of legislation that doesn't take us into account. My only thought is it might be helpful to have a highlighted version showing the changes because the document that listed the changes did not cover all of them and was a bit light on detail.
That's good to hear. Our RPO (DW) last year, said our foils were brown but had a long life yet and nothing to worry about at the moment, he's due here again in early December. I did manage to take photos of our foils last year (better camera than my previous attempt), put through a hole in some textured card (so the camera focused on foil at the same depth as the card, and not on the grill), and camera activated by a noise.

I grouted some cloud chamber sources last year. But will be sad when I start grouting the 1960s cup sources.

Regarding the guide, I always wonder why they do not include the changes document as an appendix of the main document. I then spend some time comparing the pdfs (flicking back and forward one page at a time), especially to see if the standard operating practices change. However as you say CLEAPSS does a grand job.
 

Nick Mitchener

COMMITTEE
The grouting method has changed slightly, but is still open to us. As we have seen this method come and go a bit over the years I have advised disposing of a the Strontium 90 and the Plutonium while we still can, and keeping the radium if allowed to, so then disposing of the depleted cobalt 60.

I did get a quote, just shy of £700 to do the disposal, I'm glad that wasn't necessary. We can now spend that money on a new cobalt 60 in the next couple of years.

I think it likely that at some point the advice will be to dispose of 60 year old sources regardless of halflife that is a long time for the containment system.
 
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