Should the effluent limits for manganese be modified?
Authors
Kleinman RLP; Watzlar GR
Source
Mine Drainage and Surface Mine Reclamation. Volume II: Mine Reclamation, Abandoned Mine Lands and Policy Issues. Pittsburgh, PA: U.S. Bureau of Mines, 1988 Apr; :305-310
Link
NIOSHTIC No.
20024729
Abstract
As a result of the 1912 and 1911 Clean Water Acts, effluent mine water is limited to a 30-day average concentration of 2 mg/L manganese and a single-day maximum of 4 mg/L. These limits were selected by EPA after a survey of mine water treatment facilities indicated that these values could be achieved consistently, and that in the process of removing manganese, other trace metals were also controlled. There are, however, several reasonable arguments against such low limits. Current mining operations often face much higher levels of manganese than were considered by EPA when they established the limits. As a result, many operators must raise the pH of mine water to 10 or above, increasing their chemical treatment costs by as much as 100 pct. Precipitation of manganese then lowers the pH somewhat, but an effluent pH of 9 or even higher is common. Can the limits be safely eased? Based on recent studies, it appears that manganese is only toxic to fish at low concentrations when the stream water is exceptionally soft and pure. Except in such rare instances, manganese can be considered to be about as toxic as potassium. Our work also indicates that the other, trace metals of concern are removed at a pH below 9. It is therefore suggested that the manganese effluent limits should be reexamined in light of this information.
Links with this icon indicate that you are leaving the CDC website.
The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website.
Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website.
You will be subject to the destination website's privacy policy when you follow the link.
CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website.
For more information on CDC's web notification policies, see Website Disclaimers.
CDC.gov Privacy Settings
We take your privacy seriously. You can review and change the way we collect information below.
These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. They help us to know which pages are the most and least popular and see how visitors move around the site. All information these cookies collect is aggregated and therefore anonymous. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance.
Cookies used to make website functionality more relevant to you. These cookies perform functions like remembering presentation options or choices and, in some cases, delivery of web content that based on self-identified area of interests.
Cookies used to track the effectiveness of CDC public health campaigns through clickthrough data.
Cookies used to enable you to share pages and content that you find interesting on CDC.gov through third party social networking and other websites. These cookies may also be used for advertising purposes by these third parties.
Thank you for taking the time to confirm your preferences. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page.