Bob M tells it right...PC does not hold water directly.
but I assume you mean something OVER/covering the water 'tote' itself?
the plastic drum tote needs to be insulated?..then you could papercrete plaster the entire exterior (or 'spray'crete it) BUT not cover the bottom of it (while empty) if it needed some level of support off the ground you might consider a shallow trough, fill with some perlite + sand.
Charmaine Visnesky Taylor/Publishing Eureka CA
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