Waste Crete Systems, LLC, inventor of The EnviroWash-F2 closed-loop concrete washout solution, says it is designed for use at larger sites where there is need to place concrete daily and/or several hundred yards at one time. Like the original F1, the F2 is a semi-permanent, one-hopper unit that may be hard-wired or generator-powered. Unlike the F1, the F2 has an attached forced wear tank and retractable, locking roof. The makers say the F2 hopper unit was able to handle in trials 1,800 to 2,500 yards of concrete before it had to be dumped. The concrete wastewater filtering and removal system prevents nearly 90 percent of rainwater and groundwater contamination from concrete washout, exceeding current EPA “Best Management Practice” standards. It saves fresh water by filtering it for reuse in cleaning out trucks indefinitely.