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Underground Injection Control (UIC)

Conducting and Reporting Unwitnessed Part I Mechanical Integrity Tests

It is the practice of Region 5 to witness MITs. On occasion, Region 5 will allow an owner/operator to perform an MIT unwitnessed by EPA, if it proves impossible to resolve EPA scheduling conflicts AND the owner/operator can produce either a mechanical, digital, or third-party record (this includes a test witnessed by a State UIC inspector). When EPA tells an owner/operator that they can conduct an unwitnessed MIT, the owner/operator should follow the procedures outlined below to facilitate EPA review of the test results.

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