Effect of Treatment on Nutrient Availability
As part of the revision of the Total Coliform Rule, USEPA published a series of issue papers to present available information on topics relevant to possible TCR revisions. The objectives of the issue papers were to review the available data, information and research regarding the potential public health risks associated with the distribution system issues, and where relevant identify areas in which additional research may be warranted. The issue papers serve as background material for EPA, expert and stakeholder discussions. The papers only present available information and do not represent Agency policy. Some of the papers were prepared by parties outside of EPA; EPA does not endorse those papers, but is providing them for information and review.
Effect of Treatment on Nutrient Availability
This paper examines the degree to which various types of water treatment may increase nutrient levels and have an affect on water quality in the DS. Some treatment processes can increase nutrients in the distribution systems to a level that may contribute to microbial growth in distribution system biofilms. Ozonation, for example, degrades complex humic substances to small, easily metabolized organic substances that are used for growth and energy by many biofilm organisms.