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M/DBP Rule Module
The final Stage 1 Disinfectant and Disinfection Byproduct Rule (D-DBP) and Interim Enhanced Surface Water Treatment Rule (IESWTR) rule was published in the Federal Register in November 1998. Revisions to the rule are expected to be published in the Summer of 1999. The new D-DBP and IESWTR together address balancing the risks from microbial pathogens and disinfection byproducts.
Interim Enhanced Surface Water Treatment Rule (IESWTR)The IESWTR supplements the requirements of the Surface Water Treatment Rule and provides additional protection. This rule applies to Subpart H systems [surface water systems or ground water under the direct influence of surface water (GWUDI) systems].
Disinfectant-Disinfection Byproducts Rule (D-DBP)
The purpose of the D-DBP rule is to provide moderate protection against risk from known and unknown disinfection byproducts. The rule applies to all systems that disinfect and provides 140 million people with increased protection. The rule establishes a new Maximum Contaminant Level (MCL) for Total Trihalomethanes (TTHMs) and Habacetic Acids (HAA5s) and a new Maximum Residual Disinfectant Level (MRDL) for other disinfectants.
The M/DBP Rule slide presentation is available for download as
a Microsoft® PowerPoint® presentation or an Adobe PDF file. All
other files are provided in PDF format. You
can download the PowerPoint®
Viewer or Adobe
Acrobat Reader 
if you do not already have them. (Clicking on either link above
will take you to instructions for downloading and installing the
viewers.)
Additional information regarding these rules is available on the Internet at http://www.epa.gov/OGWDW/mdbp/implement.html.
 M/DBP
Rule Module Downloads |
|
IESWTR Slide Presentation |
|
D-DBP Slide Presentation |