Mechanical Integrity Testing Requirements for Texas Operators
Updated March 2026 · 9 min read
Mechanical integrity testing (MIT) is a critical regulatory requirement for injection and disposal wells in Texas. The Railroad Commission of Texas (RRC) requires operators to demonstrate that their wells maintain mechanical integrity — meaning the wellbore, casing, and cement are sound enough to prevent fluid migration into unauthorized zones, including underground sources of drinking water (USDWs).
Failing to conduct MITs on schedule or failing the test itself can result in well shutdowns, penalties, and permit revocations. This guide covers everything Texas operators need to know.
What Is Mechanical Integrity?
Mechanical integrity means that the well's construction — casing, tubing, packer, and cement — is sufficient to prevent the movement of fluids into or between underground formations in a way that is not authorized by the well's permit. There are two components:
- Internal mechanical integrity: No significant leak in the casing, tubing, or packer — the internal conduit system is sound
- External mechanical integrity: No significant fluid movement along the outside of the casing (through channels in the cement) into unauthorized zones
Which Wells Require MIT?
MIT requirements apply to wells permitted by the RRC for injection or disposal activities:
- Saltwater disposal wells (SWD): Wells used to dispose of produced water from oil and gas operations
- Enhanced recovery injection wells: Wells used for waterflooding, CO2 injection, and other secondary/tertiary recovery methods
- Disposal wells for other fluids: Wells permitted for disposal of drilling waste fluids or other non-hazardous oilfield fluids
Production wells and monitoring wells generally do not require MIT unless they are converted to injection or disposal service.
Testing Methods
Standard Annular Pressure Test (SAPT)
The most common MIT method for demonstrating internal mechanical integrity. The annular space between the tubing and casing is pressurized and monitored for pressure decline. A successful test shows less than a specified pressure drop (typically 10% or a specific PSI threshold) over a 30-minute period, demonstrating that the tubing, casing, and packer are not leaking.
Radioactive Tracer Survey (RTS)
Used to demonstrate external mechanical integrity. A radioactive tracer is injected with the well's normal injection fluid, and a gamma ray detector is run in the well to track where the fluid goes. The survey confirms that injected fluids are going into the permitted injection zone and not migrating through cement channels to other formations.
Cement Bond Log (CBL) / Temperature Survey
Alternative methods for demonstrating external mechanical integrity. A cement bond log evaluates the quality of the cement behind the casing. Temperature surveys can detect fluid movement outside the casing by identifying thermal anomalies.
Continuous Monitoring
Some wells use continuous annular pressure monitoring as an ongoing demonstration of internal mechanical integrity. If the annular pressure remains stable (within defined limits), it provides continuous evidence that the well is not leaking. This does not replace periodic testing but can supplement it.
Testing Frequency
The RRC requires MIT at the following intervals:
- Before initial injection: MIT must be demonstrated before a newly permitted well begins injection operations
- Every 5 years: Most injection and disposal wells must demonstrate mechanical integrity at least once every five years
- After workover operations: Any workover that involves pulling the tubing, replacing the packer, or altering the well's construction requires a new MIT
- When required by the RRC: The RRC can require MIT at any time if there is reason to believe mechanical integrity may be compromised
What Happens When a Well Fails MIT
If a well fails mechanical integrity testing, the consequences are immediate and serious:
- Injection must cease: You cannot continue injecting into a well that has failed MIT
- Notification to RRC: You must notify the appropriate RRC district office of the failure
- Repair plan: You must submit a plan to repair the well and re-establish mechanical integrity
- Re-test after repair: After repairs are completed, you must pass a new MIT before resuming injection
- Potential penalties: If the failure resulted from inadequate maintenance or if you were injecting with known mechanical integrity issues, penalties can apply
Documentation and Reporting
All MIT results must be documented and submitted to the RRC. The documentation must include the test method used, test parameters (pressure, duration, tracer volumes), test results (pass or fail with supporting data), the date and time of the test, and the identity of the company and personnel who conducted the test. Test results are submitted electronically through the RRC's online system and become part of the well's public record.
Track Your MIT Schedule
With multiple injection and disposal wells, each on its own 5-year MIT cycle, keeping track of testing due dates is critical. A missed MIT deadline means you are operating without demonstrated mechanical integrity — a violation that can result in well shutdowns. CompliantIntel tracks MIT due dates for every well in your portfolio alongside all your other compliance obligations.