United States
            Environmental Protection    Office of Water            EPA 815-F-99-013
            Agency                   4607                  December 1999


          	Fact Sheet

    Under the Safe Drinking Water Act, Environmental Protection Agency (EPA) approves analytical
    methods to be used in compliance monitoring of drinking water. Periodically, the Agency revises
    or replaces compliance methods based on user suggestions, changing regulatory needs and
    improvements in technology.

    This rule, which was promulgated on December 1, 1999 (64 FR 67450), approves the use of
    updated versions of 14 EPA methods, 25 American Society for Testing and Materials (ASTM)
    methods, and 54 Standard Methods for Examination of Water and Wastewater (SM) for
    compliance with drinking water standards and monitoring requirements. Compared to the
    currently approved versions, the new versions contain primarily editorial, technical or other
    changes that make the method easier to conduct or safer. EPA will withdraw earlier versions of
    the 14 EPA methods on June  1, 2001.  Earlier versions of approved methods published by ASTM
    and SM are not withdrawn and continue to be approved  for compliance monitoring.  In addition,
    EPA is approving two new methods, EPA 515.3 and ASTM D5317-93, for acid herbicides.  EPA
    is not withdrawing approval of EPA 515.1 or 515.2 for determination of acid herbicides because
    these methods are not obsolete.

    EPA is approving the use of a new membrane filter medium, MI Agar, for the determination of
    the presence of total coliforms and E. Coli in drinking water under the Total Coliform Rule
    (TCR). MI Agar is  also approved for the enumeration of total coliforms in source water under
    the Surface Water Treatment Rule (SWTR). EPA is approving two new tests, m-ColiBlue24®
    and E*Colite®, for the simultaneous detection of total coliform and E. coli in drinking water
    under the TCR. The rule requires that microbiological source water samples collected under the
    SWTR for the determination of coliform and fecal coliform or for determination of heterotrophic
    bacteria in distribution system samples be held below 10°C during transit and storage.

    EPA is allowing a choice of six methods (ASTM D 511-93 A and B, EPA 200.7, and SM 3111 B
    SM 3120 B and 3500 Mg E) for determination of magnesium. Magnesium determinations will be
    required of systems that elect to use the magnesium control alternative to the total organic carbon
    removal requirements of the 1998 Stage One Disinfection By-Products Rule.

    EPA is also approving use of Palintest Method 1001 for determinations of total lead under the
    Lead and Copper Rule. The Palintest method uses a differential pulse anodic stripping

voltammetry technique which requires an acid digestion regardless of the turbidity of the sample.

This rule makes minor technical corrections and clarifications to the regulations. The rule:
       (l)clarifies that usually one may have up to 14-days from the date of the second analysis
       to report follow-up composite sample analyses,
       (2) amends the holding times for asbestos, nitrate and total nitrate that are specified in the
       table at §141.23(k)(2),
       (3) changes 2,4-D to "2,4-D as acid salt and ester" in the table at §141.24(e),
       (4) clarifies that the acceptance limits for successfully measuring chemical analytes in a
       performance evaluation (PE) sample apply only if that analyte has been added to the PE
       (5) amends §141.28 to allow for field or laboratory determinations of alkalinity, calcium,
       conductivity, orthophosphate and silica in drinking water samples by any person
       acceptable to the State to conduct these determinations and
       (6) amends the regulations to codify some of the provisions in the Fourth Edition of the
       Drinking Water Laboratory Certification Manual (1997).  These amendments include a
       requirement to demonstrate proficiency by successful analysis of a PE sample each year
       for chemical contaminants using the same analytical method that is used to report
       compliance monitoring results.

This rule also recommends additional methods for monitoring of chloride and sulfate which are
regulated under the National Secondary Drinking Water Regulations.

For more information, contact the Safe Drinking Water Hotline, (800) 426-4791.