It has been observed that environmentalists opposing suction dredging use data gleaned from reports that studied effects of environmental perturbations that are occurring on a system-wide basis. GEOGRAPHICAL SCALE OF SMALL-SCALE SUCTION DREDGING But first I would like to put this issue in to perspective. I will focus my water quality comments on these three areas. In water quality terms some studies have discussed turbidity, water temperature, and suspension of heavy metals into the overlying water. In nearly every instance the results have concluded that the effects were less than significant. Thank you for allowing me this opportunity to comment on the water quality aspects of small-scale suction dredge mining.Īs I have searched the scientific literature for studies on the effects of small-scale suction dredge mining on the environment I have learned that the preponderance of the published research studies have been directed towards assessment of its effect on the biology of the streams and rivers. Box 100 Sacramento, California 95812-0100 Fax: 91 email address is being protected from spam bots, you need Javascript enabled to view it State Water Resources Control Board Division of Water Quality P.O. If you are concerned about an exposure to inorganic mercury, you should consult your physician.A Good Read On The Effects Of Suction Dredging Some states set MCLs which are more strict than EPA's. for many years could experience kidney damage. EPA sets MCLs at levels that are economically and technologically feasible. MCLs ensure that drinking water does not pose either a short-term or long-term health risk. Some people who drink water containing inorganic mercury substantially in excess of the maximum contaminant level (MCL) maximum contaminant level (MCL)The highest level of a contaminant that EPA allows in drinking water. Symptoms of high exposures to inorganic mercury include: Both inorganic and organic mercury are absorbed through the gastrointestinal tract and affect other systems through this route. High exposure to inorganic mercury may result in damage to the gastrointestinal tract, the nervous system, and the kidneys.

Methylmercury field report dredging