When setting up a portable dump tank, it is important to take a moment to make sure that the liner is correctly deployed. Once water is dumped into the tank, it will be very difficult to make any adjustments and if the liner is "kattywompus" then the frame could bend or possibly break. The solution is rather simple: after unfolding the tank frame, manipulate the liner fabric so that the corners of the liner are fitted into the corners of the rigid frame. It does not have to be picture perfect - but it is important in order to prevent a problem from developing.
There was a slight grade on this asphalt surface and the dump tank liner was not "fitted" to the corners before water was dumped in the tank. Fortunately, nothing broke.
The crew here in Sumter County, Alabama, does a nice job of deploying a dump tank - taking time to position it where they want it located and making sure that the liner is fitted to the corners.
The liner was fitted to the corners and there were no problems.