Unregulated Contaminant Monitoring Regulation: Approval of Analytical Method for Aeromonas; National Primary and Secondary Drinking Water Regulations: Approval of Analytical Methods for Chemical and Microbiological Contaminants

Today's rule approves the analytical method and an associated Minimum Reporting Level (MRL) to support the Unregulated Contaminant Monitoring Regulation's (UCMR) List 2 Aeromonas monitoring. This List 2 monitoring will be conducted at 120 large and 180 small Public Water Systems (PWS) from January 1, 2003 through December 31, 2003. Today's rule also approves EPA Method 515.4 to support previously required National Primary Drinking Water Regulation (NPDWR) compliance monitoring for 2,4-D (as acid, salts and esters), 2,4,5-TP (Silvex), dinoseb, pentachlorophenol, picloram and dalapon. In addition, EPA Method 531.2 is approved to support previously required NPDWR monitoring for carbofuran and oxamyl. Minor changes have been made in the format of the table of methods required to be used for organic chemical NPDWR compliance monitoring to improve clarity and to conform to the format of other methods tables. In addition, the Presence-Absence (P-A) Coliform Test listed in the total coliform methods table was inadvertently identified as Method 9221. This has been corrected to 9221 D. Also, detection limits for "Cyanide" were added in the "Detection Limits for Inorganic Contaminants" table for the two cyanide methods, and minor editorial corrections were made. EPA is approving seven of the eight additional industry-developed analytical methods that were proposed to support previously required NPDWR compliance monitoring. These seven methods include: A method for the determination of atrazine, two methods for the determination of cyanide, two methods for the determination of total coliforms and E. coli, a method for the determination of heterotrophic bacteria, and a method for the determination of turbidity. With respect to the eighth industry-developed method proposed on March 7, 2002, EPA is deferring a decision on its approval until additional clarifying information from the vendor is evaluated. Finally, EPA is updating the information concerning the inspection of material