The U.S. Environmental Protection Agency's (USEPA's) Long Term 2
Enhanced Surface Water Treatment Rule (LT2) requires all water systems
operating under filtration avoidance status to add a second disinfectant to their
treatment system or to add filtration. As stated in the LT2 rule, the most economical
solution for unfiltered systems to meet the requirements of LT2 is typically ultraviolet
(UV) disinfection.
Each unfiltered water utility must understand and address all issues that could affect the
best method of disinfection before selecting their treatment approach. UV disinfection
may not be the best choice in all cases. Systems that have periodic high turbidity events,
taste and odor issues, disinfection byproduct (DBP) compliance issues, iron and
manganese concerns or the potential for significant changes to their source water supply
need to consider other disinfectants to determine the best second disinfectant for their
particular water system. Other alternatives may allow these systems to deal with their
specific challenges and bring their system into compliance with LT2 at the same time
and remain an unfiltered water system. In this context, this study discusses three (Ketchikan Public Utilities, the City of Kodiak, and the City and Borough of Sitka) of Alaska's unfiltered water systems that
have water quality challenges that necessitated careful review of the available
disinfection alternatives before disinfectant selection was completed. Includes figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 6 |
| Published : | 11/01/2009 |
