How do I use a Van Veen Grab or Dredge?
1. The Van Veen Grab requires a winch (66-C10), winch mount (66-C52) and stainless steel cable (61-B14) for proper operation. Attach one end of the cable to your winch and the other to the dredge. Ensure that all connections are very tight to prevent loss of the sampler.
2. Set the Pinch-Pin (tripping mechanism) on the dredge. The Pinch-Pin must be inserted with the flat portion facing up and down. Be careful not to place fingers or hands on or into any pinch points.
3. Lower the dredge through the water column. Make sure that in the final 1-2 feet there is little to no disturbance.
4. Trip the dredge by allowing the line to become slack. The jaws should clamp shut, grabbing a sediment sample.
5. Winch the dredge to the surface in a slow, even manner.
6. Bring the dredge into your boat and tilt slightly to pur off the water. Be careful not to pour out the sediment!
7. Empty the contents of the dredge into a Ponar Wash Frame (188-E50).
8. Collect and handle samples as your procedures dictate.
9. Decontaminate the dredge between each unique sample location, or have a clean, dedicated dredge for each sample location.
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