Mission Bend MUD 2 - Public Notice of Chemical Monitoring

The Texas Commission on Environmental Quality (TCEQ) has notified the Mission Bend MUD 2, TX1011826, water

system that the drinking water being supplied to customers had exceeded the Maximum Contaminant Level (MCL)

for total trihalomethanes. The U.S. Environmental Protection Agency (U.S. EPA) has established the MCL for total

trihalomethanes to be 0.080 milligrams per liter (mg/L) based on the locational running annual average (LRAA), and

has determined that it is a health concern for levels above the MCL. Analysis of drinking water in your community for

total trihalomethanes indicates a compliance value in quarter two of 0.083 mg/L for DBP2-03.

Trihalomethanes are groups of volatile organic compounds that are formed when chlorine, added to the water during

the treatment process for disinfection, reacts with naturally-occurring organic matter in the water.

Some people who drink water containing trihalomethanes in excess of the MCL over many years may experience

problems with their liver, kidney, or central nervous systems, and may have an increased risk of getting cancer.

You do not need to use an alternate water supply. However, if you have health concerns, you may want to talk to your

doctor to get more information about how this may affect you.

We are taking the following actions to address this issue:

The TCEQ Subcontractor has collected, and continues to collect, quarterly samples and test for TTHMs since 2013

with only one sample, which was collected in April 2024, exceeding the limit. At the time of collection, one of our

water plants was offline while maintenance was being performed, so the results were not necessarily representative of

the water that is normally distributed. We expect the TTHM levels to return to normal now that both water plants are

on-line. We will continue to collect laboratory samples and monitor the situation until the TTHM concentration is

back to the anticipated levels.

If you have questions regarding this matter, you may contact Michael Thornhill at 832-490-1635 and/or by e-mail

at mthornhill@sienviro.com.