Executive Council

Authorizes Release:

Vice President for Administration and Finance

Responsible Area:

Facilities Services

Review Cycle:

Annually or as required

Last Review:

March 2021

Related Policies and Additional References:



The purpose of this document is to describe the procedure for the periodic inspection of the UST Test Wells and subsequent removal of liquid in the wells if required.


The test wells were installed by Raba Kistner Environmental Engineers in 1986 because of a leaking underground fuel tank in the Facilities Compound. The purpose of the test wells is to monitor the subsurface conditions surrounding the UST for presence of gasoline or diesel contamination. Two of the test wells are located in the immediate area surrounding the USTs, the remaining two test wells are down gradient of the USTs.


This document applies to the St. Mary’s Facilities Services.

Reference Documents

  • Drawing: Underground Storage Tank Test Wells (Appendix – B)
  • Underground Storage Tanks (UST) Description and Procedures (March 4, 2011)


  • WHEN: The inspection shall take place in December coinciding with the annual integrity and alarm testing of the underground storage tanks. However, the test should not take place on a rainy day or if the most recent measureable rainfall in Bexar County was equal to or greater than 0.33 inches in any one hour period.
  • If the rainfall exceeds this amount, the test should take place two weeks after a period of no precipitation.
  • HOW OFTEN: Frequency of inspection is annual if no liquid is observed in any of the wells. If liquid is observed in any one of the observation wells, each well will be visually inspected for liquid on a monthly basis until no liquid is observed.
  • WHERE: Refer to drawing “Underground Storage Tank Test Wells” to identify locations and dimensions of the applicable test wells.
  • Inspection procedure: Remove the sealed well cap at ground level. Note: When the test is completed, the cap must be re-installed and secured.
  • Examine the contents of the well by looking down the well tube with a flashlight.
  • If no liquids are sighted, then the hole is considered dry and the test is complete with negative results (indicating no liquids present in the test well). No other action is required for this well during this inspection period.
  • If the light is reflected then liquids are considered present and the test is recorded as positive. The liquid must be sampled and evaluated for odor to determine if it is contaminated groundwater.
  • Sampling procedure: If liquids are present, a sample will be removed by lowering a small sump pump with a discharge hose. The sample should be collected in a container.
  • If the liquid is determined not contaminated, the results should be indicated as such on the form. The non-contaminated groundwater may be removed and discharged into the sanitary sewer or storm drain system.
  • If the liquid is identified to be potentially contaminated with gasoline or diesel, it must be sent to the lab for testing.
  • Liquid in these wells can be pumped into above ground storage containers but must await test results to determine proper disposal requirements. Note: Complete form (Appendix-A) to include all relevant information for each annual and monthly event.


The annual inspection and any required monthly inspections of the test wells shall be performed and/or verified by the Manager of Grounds.


All personnel responsible or performing or verifying the Inspection of the UST Test Wells shall read and review the following procedures: Underground Storage Tanks (UST) Description and Procedures, and Underground Storage Tank Test Well Inspection.

Record Keeping

The completed UST Test Well Inspection Form (refer to Appendix–A) must be signed by the Grounds Manager or designated representative. Records of UST Test Well Inspection results will be maintained and filed in the Facilities Department Front Office for a minimum of 30 years.

Available in the Administration and Finance Office:
Appendix A: UST Test Well Inspection Form
Appendix B: Drawing – Underground Storage Tank

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