R 325.10719n Disinfection byproducts; reporting and recordkeeping requirements.

Rule 719n. (1) A community or nontransient noncommunity water supply that is subject to disinfection byproducts requirements of R 325.10610d shall report all of the following: (a) The supply shall report all of the following information for each monitoring location to the department within 10 days of the end of a quarter in which monitoring is required: (i) Number of samples taken during the last quarter. (ii) Date and results of each sample taken during the last quarter. (iii) Arithmetic average of quarterly results for the last 4 quarters for each monitoring location (LRAA), beginning at the end of the fourth calendar quarter that follows the compliance date and at the end of each subsequent quarter. If the LRAA calculated based on fewer than 4 quarters of data would cause the MCL to be exceeded regardless of the monitoring results of subsequent quarters, the supply shall report this information to the department as part of the first report due following the compliance date or anytime thereafter that this determination is made. If the supply is required to conduct monitoring at a frequency that is less than quarterly, the supply shall make compliance calculations beginning with the first compliance sample taken after the compliance date, unless the supply is required to conduct increased monitoring under R 325.10719k. (iv) Whether, based on R 325.10610(2), R 325.10610d and R 325.10719h to R 325.10719n, the MCL was violated at a monitoring location. (v) Any operational evaluation levels that were exceeded during the quarter and, if so, the location and date, and the calculated TTHM and HAA5 levels. (b) A subpart H supply that is seeking to qualify for or remain on reduced TTHM/HAA5 monitoring shall report all of the following source water TOC information for each treatment plant that treats surface water or groundwater under the direct influence of surface water to the department within 10 days of the end of a quarter in which monitoring is required: (i) The number of source water TOC samples taken each month during last quarter. (ii) The date and result of each sample taken during last quarter. (iii) The quarterly average of monthly samples taken during last quarter or the result of the quarterly sample. (iv) The running annual average (RAA) of quarterly averages from the past 4 quarters. (v) Whether the RAA exceeded 4.0 mg/L. (c) The department may choose to perform calculations and determine whether the MCL was exceeded or the supply is eligible for reduced monitoring instead of having the supply report that information. (2) The supply shall retain monitoring plans and monitoring results of monitoring conducted under R 325.10610d and R 325.10719h to R 325.10719n, as required by R 325.11506 (1) (g).