Posted previously by another WSer
Sulfuric acid weighs ~15 pounds per gallon; heavy compared to water, which is about 9 (sorry Europe). If it was available to SA, it would have been in 55 gallon drums, and he would have required the entire drum to submerge a body. Even then, it would take weeks to fully dissolve and would leave behind a gooey residue. It seems unlikely that Shawn could have gone to work and removed a barrel whose contents alone weighed over 800 pounds, not to mention doing so without anyone noticing.
Nancy is where a lot of rumors start.
Yeah, I never bought into the "using acid to dissolve a body" theory. Using it to clean up evidence, maybe - or to manufacture drugs - but the quantity needed to get rid of HD - no way.