– To collect a sample of water free of contamination from the surface water.
– To avoid sample contamination from the internal power springs.
– To eliminate unwanted high buoyancy problems of water samplers with rigid body.
– To drain the sampler without letting the air come into contact with the water sample.
A spine assembly and a front bracket sustain two ball-valve closure mechanisms at both ends of the sampler. The ball valve arrangement allows for a sequential close-openclose deployment. A pair of pivoting wings attached to the spine sustains and protects a polyethylene bag. The bags open ends are attached to the ball-valve closure mechanism housings. A pressure release valve which controls the closure mechanics is securely attached to the front bracket. The drain valve is directly attached to the front bracket. It activates them at 10 feet under the water surface. The drain valve is directly attached to the very lower section of the bag.