Ok,
Mark first. We are not due to EPA regulations allowed to discharge down the stormwater drain, so what we did in this case was pull up the lid on the pit, block off the outlet and place 3" vacuum hose. When finished we jet out the pit, vacuum, unblock outlet. The other pits were sand bagged off. The gully sucker holds 2500 gallons, in this job we recovered 800 gallons of wash waters. We then took them to a liquid waste treatment plant at a cost of 48c US a gallon. I think they charge the client 72c Gallon + labour. I am trying to rigg the Steel Eagle up directly to this tanker with lighter 2" vacuum hose and a 2" ball valve on the deck. Steel Eagle say I can't do it - 'But where theres a will there's a way'. I've already attached spray suppresser skirting, so if I replace this with a more rigid rubber seal I should be on the money.