Well Water Nerd

Gross alpha in Texas well water

In Texas, 12% of 2,417 tested private well samples exceeded the EPA limit for gross alpha (15 pCi/L).

Gross alpha is a screening test for radioactive elements in water, mainly radium and uranium from granite bedrock. A high result means one of those is present and the specific test should follow. Alpha emitters raise cancer risk when swallowed over years.

Check your gross alpha number

Type the value from your lab report. It is compared to the EPA limit, the same way the full interpretation does it.

Getting it fixed

Book a free in-home water test with a licensed local company, or see the treatment guide for what removes gross alpha.

By county, from individual samples

Public monitoring samples against the EPA limit (15 pCi/L); counties with at least 30 samples.

CountySamplesDetectedAbove EPA limitMedianHighest
Duval4678%35%939 pCi/L
Live Oak3770%30%4.433 pCi/L
Dawson3077%27%8.295 pCi/L
Matagorda3468%15%5.0528 pCi/L
Lavaca3757%11%2.840.1 pCi/L
Gillespie3161%6%4.2718 pCi/L
Colorado3751%5%2.716 pCi/L
San Saba3853%5%2.116.5 pCi/L
Erath4766%4%3.424 pCi/L
Wharton3364%3%2.730 pCi/L
Lipscomb3474%0%2.748.1 pCi/L

Sources

  • Individual samples from the USGS Water Quality Portal and state monitoring, summarized per geography. gross alpha counts and shares are listed on each county and town page with their sources.