For your information and assistance in locating labs for well testing for water quality, the following are: (1) site you can go to for a list of certified labs for public drinking water, and (2) TCEQ approved commercial labs.

http://www.tceq.state.tx.us/compliance/compliance_support/qa/drinking_water_certification.html

http://www.tceq.state.tx.us/assets/public/permitting/watersupply/pdw/approvedlabs.pdf