EPA Code 2456 · Maximum Contaminant Level Exceedance
violations
EPA Limit
0.06 mg/L
Last Reading
283 UG/L
First Reported
Oct 2022
Most Recent
Jul 2023
What this violation means
Haloacetic Acids (HAA5) are the second major group of disinfection byproducts after TTHMs. They form by the same mechanism — chlorine reacting with organic matter — and pose similar long-term cancer risks. Utilities are required to test quarterly at distribution-system locations to track HAA5 levels.
Recommended precautions
- →Activated carbon filtration removes most HAA5.
- →Reverse osmosis is highly effective.
- →Unlike TTHMs, HAA5 do not significantly off-gas. Use treatment rather than aeration.
- →Long-term ingestion is the primary concern, not short-term skin contact.