JBSA-RANDOLPH, Texas — The Joint Base San Antonio-Randolph drinking water system recently violated a drinking water standard. Although this is not an emergency, customers have a right to know what happened, what they should do and what has been done to correct this situation.
The flight routinely monitors for the presence of drinking water contaminants. On March 14, a notice was received from the Texas Commission on Environmental Quality, or TCEQ, that samples collected from Oct. 1 to Dec. 31, 2017, showed that the system exceeded the maximum contaminant level, or MCL, for fluoride.
The average level of fluoride in samples taken during this time period indicated a compliance value of 4.4 milligrams/liter (mg/L) for one sample site, EP003. The standard for fluoride is that the average of samples taken over the last year may not exceed 4.0 mg/L.
What does this mean?
This is not an emergency. If it had been, people would have been notified within 24 hours. Fluoride in small amounts helps prevent tooth decay.
However, some people who drink water containing fluoride in excess of the MCL over many years could get bone disease, including pain and tenderness of the bones.
Fluoride in drinking water at half the MCL or greater may cause mottling of children’s teeth, usually in children younger than nine years of age. Mottling, also known as dental fluorosis, may include brown staining and/or pitting of the permanent teeth.
This problem occurs only in developing teeth, before they erupt from the gums. Although it takes many years, mottling can occur after a relatively short period of exposure.
What should I do?
Children under the age of nine should use an alternative source of water that is low in fluoride. In addition, you may want to consult your dentist about whether to avoid dental products containing fluoride.
Adults and children over age nine should consult their dentist or doctor and show him/her this notice to determine if an alternate source of water low in fluoride should be used.
What is being done?
The water at JBSA-Randolph is safe to drink. The high level of fluoride was the result of a poor sampling location. The area of concern is only at the entry point of site 3 (EP003), which is between the high school and the medical clinic.
The injection point (where the fluoride was introduced) and sample site (where it was collected) were only three feet away from each other. This was not enough distance for adequate dilution of additives (fluoride) to the drinking water supply.
The Bioenvironmental Engineering Flight and the water plant operators have corrected this issue by moving the injection point 15 feet further away from the sampling point. Current fluoride results at the sampling site have been reduced by more than half and remain below the MCL.
In addition, flight members have taken samples at the nearest public entry point at the high school and medical clinic, approximately half a mile away from the EP003 site, and the results were well below the MCL. The Bioenvironmental Engineering Flight also conducts monthly sampling for fluoride at the Child Development Center and Youth Center, which have never exceeded the MCL.
Again, the water is safe to drink. Drinking water customers at JBSA-Randolph are not affected and therefore, JBSA-Randolph is not required to provide an alternate source of water.
For more information, call the Bioenvironmental Engineering Flight at 210-652-3256.