Due to an increased focus from U.S. EPA on reducing mercury, the Indiana Department of Environmental Management has been working with wastewater treatment plants to increase awareness of potential mercury sources in Indiana communities and to encourage practices that reduce the amount of mercury released down the drain by local business and industry.
Why The Concern?
Mercury Is Toxic:
Although mercury performs many useful functions, it is toxic and can impair the way we see, hear and function. In the environment, a percentage of mercury undergoes a biological/chemical process and is converted to methylmercury, which is a more toxic form of mercury. Mercury poisoning can attack the central nervous system in humans. Women of child-bearing age and children, especially those under the age of six, are most susceptible to mercury poisoning.
Stricter Regulation:
Wastewater treatment plants are facing increased regulatory attention for levels of mercury in the wastewater they treat and ultimately discharge into Indiana waters. As a result, treatment plants throughout the state need the cooperation of business, industry and citizens to minimize the amount of mercury escaping down the drain.
Methods Used
Mercury is a toxic metal that has high bioconcentration and bioaccumulation rates when in the form of methylmercury. Water quality criteria treat all mercury as if it is in the form of methylmercury, the most common organic mercury compound in the environment.
Method 1631, Revision E is a mercury analytical method approved by U.S. EPA in 2002 that can measure the concentration of mercury at a level below Indiana's existing aquatic life, human health, and wildlife water quality criteria. Prior to the availability of this method, laboratory analysis could only measure mercury at a level well above these water quality criteria. With the use of Method 1631, compliance assessment indicates that the majority of wastewater discharging facilities in Indiana will not be able to consistently meet their NPDES permit limits for mercury.
For information on cleaning up mercury, see Mercury Spill Information and Cleanup Guidance [PDF].
Outreach Materials
- Auto & Appliance Repair
- Colleges & Universities
- Dental Offices
- General Industry
- HVAC-R
- Health Care Facilities