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Water Science Pictures
Sampling mud from a lake bottom

For some special projects the mud at the bottom of lakes must be sampled. In this instance, there was a need to dredge a lake bottom of excess mud. But, lake bottoms are the place where lots of pesticide residue like to end up, especially the old, dangerous pesticides, like DDT. It would have been dangerous to dredge up mud containing too much pesticides, so a sampling of the lake bottom had to be made.

A long metal tube containing a smaller plastic tube is shoved into the lake bottom to get the mud. As this messy hydrologist found out, you need to be careful when handling any water-sampling equipment.