Suppliers of water using surface water or ground water under the direct influence of surface water using conventional filtration treatment serving 10,000 or more individuals shall comply with the requirements of 40 CFR Part 141, Subpart L, beginning January 1, 2002. Suppliers of water using surface water or ground water under the direct influence of surface water using conventional filtration treatment serving fewer than 10,000 individuals shall comply with the requirements of 40 CFR Part 141, Subpart L, beginning January 1, 2004. The treatment requirement to control disinfection by product precursors mandates installing and properly operating water treatment processes which reliably achieve at least: Enhanced coagulation and enhanced softening requirements of §D of this regulation; Alternate compliance criteria for enhanced coagulation and enhanced softening set forth in 40 CFR §141.135(a)(2) and the monitoring requirements for disinfection byproduct precursors (DBPP) set forth in 40 CFR §141.132(d); or Additional alternative compliance criteria for softening systems set forth in 40 CFR §141.135(a)(3) and monitoring requirements set forth in 40 CFR §141.132. A supplier of water using surface water or ground water under the direct influence of surface water using conventional filtration treatment is considered to be in compliance with §C(1) of this regulation if the supplier of water meets the following provisions: Step 1 Total Organic Carbon (TOC) percent reduction set forth in 40 CFR §141.135(b)(2); or Step 2 TOC percent reduction set forth in 40 CFR §141.135(b)(3)—(4). A supplier of water shall monitor and report to the Approving Authority set forth in 40 CFR §141.135 to ensure compliance with the requirements for disinfection byproduct precursors.