I had high hopes for VOLCANO, especially since it was directed by the guy who brought us THREADS, but while it was mildly entertaining it just never clicked for me on an emotional or even believability level. The special effects were dated, the forced emotional music was annoying, none of the characters had any depth and it has more of a made-for-TV feel to it than something actually released in the theaters. If you don't take it too seriously it's a good movie to laugh at, but that's about it.
VOLCANO drinking game: anytime somebody does something heroic, anytime somebody says "Oh my God" or the like, every time TLJ yells out an order, every time the firemen aim their fire hoses towards the middle of the lava flow instead of the leading edge, every time something doesn't melt when the lava hits it (streetlight poles are a good example), every time a dog barks at the lava and every time TLJ's daughter just stands there frozen like a brain dead idiot.
I'm no scientist, but I would think you would want the barrier to arch into the oncoming lava flow instead of with it. Just think about all of the major dams. Probably has something to do with compressing under pressure instead of ripping apart.