La. Admin. Code tit. 43 § XVII-3129

Current through Register Vol. 50, No. 11, November 20, 2024

Section XVII-3129 - Well and Salt Cavern Mechanical Integrity Pressure and Leak Tests

A. The operator of the salt cavern well and cavern shall have the burden of meeting the requirements for well and cavern mechanical integrity. The Office of Conservation shall be notified in writing at least seven days before any scheduled mechanical integrity test. The test may be witnessed by Office of Conservation personnel but must be witnessed by a qualified third party.

B. Frequency of Tests. Without exception or variance to these rules and regulations, all salt cavern wells and salt caverns shall be tested for and satisfactorily prove mechanical integrity before being placed into initial waste disposal service. After the initial test for well and cavern mechanical integrity, all subsequent tests shall occur at least once every five years. Additionally, mechanical integrity testing shall be done for the following reasons regardless of test frequency:

1. after any alteration to any cemented casing or cemented liner;

2. after performing any remedial work to reestablish well or cavern integrity;

3. before suspending salt cavern waste disposal operations for reasons other than a lack of well/cavern mechanical integrity if it has been more than three years since the last mechanical integrity test;

4. before well/cavern closure; or

5. whenever the Office of Conservation believes a test is warranted.

C. Test Method

1. All mechanical integrity pressure and leak tests shall demonstrate no significant leak in the salt cavern, wellbore, casing seat, and wellhead. Test schedules and methods shall consider neighboring activities occurring at the salt dome to reduce any influences those neighboring activities may have on the salt cavern being tested.

2. Tests shall be conducted using the nitrogen-brine interface method with density interface and temperature logging. An alternative test method may be used if the alternative test can reliably demonstrate well/cavern mechanical integrity and with prior written approval from the Office of Conservation.

3. The salt cavern pressure shall be stabilized before beginning the test. Stabilization shall be reached when the rate of cavern pressure change is no more than 10 PSIG during 24 hours.

4. The stabilized test pressure applied at the surface shall be a minimum of 125 percent of the maximum cavern surface operating pressure or 500 PSIG whichever is greater. However, at no time shall the test pressure calculated with respect to the shallowest occurrence of either the cavern roof or deepest cemented casing seat and as measured at the surface exceed a pressure gradient of 0.80 PSI per foot of vertical depth. The salt cavern well or salt cavern shall never be subjected to pressures over the maximum allowable operating pressure or exceed the rated burst or collapse pressure of all well tubulars (cemented or hanging strings) even for short periods during testing.

5. A mechanical integrity pressure and leak test shall be run for at least 24 hours after cavern pressure stabilization and must be of sufficient time duration to ensure a sensitive test. All pressures shall be monitored and recorded continuously throughout the test. Continuous pressure recordings may be achieved through mechanical charts or may be recorded digitally. Mechanical charts shall not exceed a clock period of 24-hour duration. The chart shall be scaled such that the test pressure is 30 percent to 70 percent of full scale. All charts shall be selected such that its scaling is of sufficient sensitivity to record all fluctuations of pressure, temperature, or any other monitored parameter.

D. Submission of Pressure and Leak Test Results. One complete copy of the mechanical integrity pressure and leak test results shall be submitted to the Office of Conservation within 30 days of test completion. The report shall include the following minimum information:

1. current well and cavern completion data;

2. description of the test procedure including pretest preparation;

3. copies of all wireline logs performed during testing;

4. tabulation of measurements for pressure, volume, temperature, etc.;

5. interpreted test results showing all calculations including error analysis and calculated leak rates; and

6. any information the owner or operator of the salt cavern determines is relevant to explain the test procedure or results.

E. Mechanical Integrity Test Failure

1. Without exception or variance to these rules and regulations, a salt cavern well or salt cavern that fails a test for mechanical integrity shall be immediately taken out of waste disposal service. The failure shall be reported to the Office of Conservation according to the Notification Requirements of §3109. H The owner or operator shall investigate the reason for the failure and shall take appropriate steps to return the salt cavern well or salt cavern to a full state of mechanical integrity. A salt cavern well or salt cavern is considered to have failed a test for mechanical integrity for the following reasons:

a. failure to maintain a change in test pressure of no more than 10 PSIG over a 24-hour period;

b. not maintaining nitrogen-brine interface levels according to standards applied in the salt cavern storage industry; or

c. fluids are determined to have escaped from the salt cavern well or salt cavern during waste disposal operations.

2. Written procedures for rehabilitation of the salt cavern well or salt cavern, extended salt cavern monitoring, or abandonment (closure and post-closure) of the salt cavern well or salt cavern shall be submitted to the Office of Conservation within 30 days of mechanical integrity test failure.

3. Upon reestablishment of mechanical integrity of the salt cavern well or salt cavern and before returning either to waste disposal service, a new mechanical integrity pressure and leak test shall be performed that demonstrates mechanical integrity of the salt cavern well or salt cavern. The owner or operator shall submit the new test results to the Office of Conservation for written approval before resuming waste disposal operations.

4. If a salt cavern well or salt cavern fails to demonstrate mechanical integrity and where mechanical integrity cannot be reestablished, the Office of Conservation may require the owner or operator to begin closure of the well or cavern within six months according to an approved closure and post-closure plan.

5. If a salt cavern fails mechanical integrity and where rehabilitation cannot be accomplished within six months, the Office of Conservation may waive the six-month closure requirement if the owner or operator is engaged in a salt cavern remediation study and implements an interim salt cavern monitoring plan. The owner or operator must seek written approval from the Office of Conservation before implementing a salt cavern monitoring program. The basis for the Office of Conservation's approval shall be that any waiver granted shall not endanger the environment, or the health, safety and welfare of the public. The Office of Conservation may establish a time schedule for salt cavern rehabilitation, cessation of interim salt cavern monitoring, and eventual salt cavern closure and post-closure activities.

F. Prohibition of Waste Acceptance During Mechanical Integrity Failure

1. Salt cavern waste disposal facilities with a single cavern are prohibited from accepting E& P wastes at the facility until mechanical integrity of the salt cavern well or salt cavern is documented to the satisfaction of the Office of Conservation.

2. Salt cavern waste disposal facilities with multiple salt caverns may continue accepting E& P wastes if the other cavern(s) at the facility exhibit mechanical integrity.

La. Admin. Code tit. 43, § XVII-3129

Promulgated by the Department of Natural Resources, Office of Conservation, LR 29:932 (June 2003).

AUTHORITY NOTE: Promulgated in accordance with R.S. 30:4 et seq.