Page 1 of 2 Office of Ground Water and Drinking Water February 6 , 2013

MEMORANDUM

SUBJECT : Basis for Expedited Approval of Methods from the 22 nd Edition of Standard Methods for the Examination of Water and Wastewater

FROM : Jennifer Best, Microbiologist , Technical Support Center

TO : The Record

This memo documents the review that w as conducted on methods published in the 22 nd edition of Standard Methods for the Examination of Water and Wastewater . It provides the background information on why EPA is approvin g these methods using the expedited method approval process. Each method is discussed individually below:

(1) Standard Method 9215 B

. The version published in the 20 th edition of Standard Methods for the Examination of Water and Wastewater was used as t he basis for comparison, because it is currently cited in the drinking water regulations at 40 CFR 141.74 (a)(1) for the determination of heterotrophic
bacteria

. The version of this method published in the 22 nd edition of Standard Methods for the Examination of Water and Wastewater is similar to the approved version with some minor editorial revisions that do not impact the effectiveness of the method. Therefore, the 22 nd edition version of this method is as equally effec tive as the promulgated version of the method.

(2) Standard Method s 9221 A, B

. The version s published in the 20 th edition of Standard Methods for the Examination of Water and Wastewater w ere used as the basis for comparison, because they are
cited in th e drinking water regulations at 40 CFR 141.2 1(f) ( 3), 40 CFR 141.74(a)(1) while more specifically, SM 9221B.1,B.2 is cited in 40 CFR 141.852(a)(5) for the determination of total coliform
bacteria

. The versions of these methods published in the 22 nd edition of Standard Methods for the Examination of Water and Wastewater are similar to the approved version s with some minor editorial revisions that do not impact the effectiveness of the method s . Therefore, the 22 nd edition versions of these methods are as equ ally effective as the promulgated versions of the methods.

(3) Standard Method 9221C. The version published in the 20 th edition of Standard Methods for the Examination of Water and Wastewater was used as the basis for comparison, because it is cited in the drinking water regulations at 40 CFR 141.74(a)(1)for the estimation of total and fecal coliform bacteria density. The version published in the 22 nd edition of Standard Methods for the Exami nation of Water
and Wastewater has editorial revisions along with modified Most Probable Number (MPN) tables which were developed with improved statistical approaches. The changes to the version of the method published in the 22 nd edition of Standard Meth ods for the Examination of Water and Wastewater do not impact the effectiveness of the method. Therefore, the 22 nd edition version of this method is as equally effective as the promulgated version of the method.

( 4 ) Standard Method 9221 E. The versio n published in the 20 th edition of Standard Methods for the Examination of Water and Wastewater was used as the basis for comparison, because it is cited in the drinking water regulations at 40 CFR 141.21(f)( 5 ) and 40 CFR 141.74(a)(1) for the determination of fecal
coliform bacteria

. The version of this method published in the 22 nd edition of Standard Methods for thePage 2 of 2 Examination of Water and Wastewater is similar to the approved version with some minor editorial revisions that do not impact the effectiveness of the method. Therefore, the 22 nd edition version of this method is as equally effective as the promulgated version of the method.

( 5 ) Standard Method 9221 F. The version published in the 2 0th edition of Standard Methods for the Examination of Water and Wastewater was used as the basis for comparison because it is cited in the drinking water regulations at 40 CFR 141.402(c)(2) and more specifically 9221 F.1 is cited at 40 CFR 141.852(a)(5) for the determination of Escherichia coli

. The version of this method published in the 22 nd

edition of Standard Methods for the Examination of Water and Wastewater is similar to the approved version with some minor editorial revisions that do not impact the effectiveness of the method.
Therefor e, the 22 nd edition version of this method is as equally effective as the promulgated version of
the method.

( 6 ) Standard Method 9222 D

. The version published in the 20 th edition of Standard Methods for the Examination of Water and Wastewater was used a s the basis for comparison, because it is cited in the drinking water regulations at 40 CFR 141.74(a)(1) for the determination of fecal coliform bacteria. The version of this method published in the 22 nd edition of Standard Methods for the Examination of Water
and Wastewater is similar to the approved version with some minor editorial revisions that do not impact the effectiveness of the method. Therefore, the 22 nd edition version of this method is as equally
effec tive as the promulgated version of the method.

( 7 ) Standard Method 9223

. The version published in the 20 th edition of Standard Methods for the Examination of Water and Wastewater was used as the basis for comparison, because it is cited in the drinking water regulations at 40 CFR 141.21(f)(3), 40 CFR 141.852(a)(5), 40 CFR 141.74(a)(1) for the
determination of total coliform bacteria , and at 40 CFR 141.402(c)(2) and at 40 CFR 141.852(a)(5) for the
determination of Escherichia coli

. The version of this m ethod published in the 22 nd edition of Standard Methods for the Examination of Water and Wastewater is similar to the approved version with some minor editorial revisions that do not impact the effectiveness of the method. Therefore, the 22 nd

edition ver sion of this method is as equally effective as the promulgated version of the method.