Greetings listmembers,

I'm collecting cave water samples for D/H and del-18 analysis. I wanted to
know if anyone could offer any advice regarding HDPE plastic storage
containers. The samples would be collected over a month and stored in HDPE
drums under a good few cm's of paraffin oil prior to more satisfactory
storage in glass bottles.

I have the option of using drums with either 2 mm or 6 mm wall thicknesses.
Since there is a LARGE difference in price between the two drums, I wanted
to know if anyone could offer any advice on the minimal wall thickness that
could be used while still avoiding diffusion through the plastic?

Thanking you,

Pauline.