Yellow Pages and find "well drilling equipment and supplies". Inquire of one or two of the companies the feasibility of using a driven well point (sand point) driven on drain pipe under the slab with a sledge. If your soil is not too compact (and with that much water, I suspect it's not), you can probably drive a drain line under the slab. The pros at the well supply co. can tell you what's available. Or you can give the water a fancy name and sell it at a buck a bottle? Luck, Kizmet