22 Jan 2019

Levels of Total Trihalomethanes and Haloacetic Acids Above Drinking Water Standards


In keeping with National Primary Drinking Water Regulations, we are obliged to inform you that we may be in violation of state regulations because drinking water being served to our customers in the Quantico MCB Mainside system did not comply with Primary Maximum Contaminant Levels for total trihalomethnes and haloacetic acids.


We routinely monitor for the presence of drinking water contaminants.  Testing results from 1st quarter 2018 through 4th quarter 2018 show that our system exceeds the standard, or maximum contaminant level (MCL), for total trihalomethanes and haloacetic acids.  The standard for total trihalomethanes is 0.080 mg/L.  The average level of total trihalomethanes over this period at two of our four sample sites was 0.081 mg/L and 0.083 mg/l.  The standard for haloacetic acids is 0.060 mg/L.  The average level of haloacetic acids over this period at one of our four sample sites was 0.063 mg/L.  Due to the rolling 12-month average levels repeatedly exceeding the PMCL, MCBQ has issued a contract to upgrade the Base’s water treatment system and it is expected to be in operation in 2019. 


Even though this is not an emergency, as our consumers, you have the right to know what happened and what we are doing to correct this situation. There is nothing you need to do at this time.  However, if you have specific health concerns, consult your doctor.  This is not an immediate health risk.  If it had been, you would have been notified immediately.  You do not need to use an alternative (e.g. bottled) water supply.  We continue to monitor and sample as required and consumers will be notified if there are any further issues.  HAA5 and TTHM are both by-products of drinking water disinfection by chlorination.  It has been shown that some people who drink water containing HAA5 in excess of the PMCL over many years may have an increased risk of getting cancer.  It has also been shown that some people who drink water containing TTHMs in excess of the PMCL over many years could experience problems with their liver, kidneys, or central nervous systems, and may have an increased risk of getting cancer.  If consumers have any questions regarding the MCBQ drinking water system, they should contact the MCBQ POC listed below.


Please share this information with all the other people who drink this water, especially those who may not have received this notice directly (for example, people in apartments, nursing homes, schools, and businesses).  You can do this by posting this notice in a public place or distributing copies by hand or mail.


For more information concerning drinking water, visit, or please contact CDR Preston Taylor, PE at 703-784-5409.

Marine Corps Base Quantico