State officials are investigating how Texas Brine Co. LLC handled naturally occurring radioactive material in Assumption Parish — where a large sinkhole was found Aug. 3 — and whether it was illegally disposed of inside the Napoleonville Dome in the mid-1990s.
The state Department of Environmental Quality confirmed last week that a 1979 state statute prohibited disposal of naturally occurring radioactive material in large underground salt deposits like the Napoleonville Dome until legislative changes in 1999 made such disposal legal.
“What we’re going to do is investigate this thing the best we can with the information from 1995 and move forward as appropriate,” DEQ spokesman Rodney Mallett said.
In August 1995, Texas Brine considered putting up to 20 cubic feet of NORM in an underground company cavern in the Napoleonville Dome and in another salt dome in Lafourche Parish, according to DEQ and state Office of Conservation records.
The Office of Conservation did not object, but it is unclear if Texas Brine followed through on the plans.
Texas Brine officials, in a statement last week, said they did not put NORM in the caverns after making initial regulatory inquiries but it remains on site under a standing DEQ license.
“Since the concentration level of NORM was so low, and the amount of accumulated scale was so small, it was determined to leave the scale in place,” Texas Brine officials said in the statement, which came after the company was told that DEQ concluded NORM disposal in salt domes was illegal in 1995.
The statement contradicts detailed comments from company officials on Aug. 10 that a small amount of NORM was disposed of in the Napoleonville Dome with Office of Conservation approval but that it posed no risk to the public.
The processes involved with oil and gas drilling, along with a variety of other industrial processes such as brine production, can concentrate naturally occurring radioactive isotopes underground at widely varying levels, but sometimes can pose a risk, according to the U.S. Environmental Protection Agency.
Subsequent testing by DEQ and the EPA has shown that surface radiation in the Bayou Corne area, including in the sinkhole, is not above background levels and poses no risk, state officials have said.
In 1979, the state Legislature prohibited disposal of “radioactive waste or other radioactive material of any nature” in salt domes. The law, which took effect Jan. 1, 1980, arose during controversy over U.S. Department of Energy plans to put high-level radioactive waste, such as from nuclear power plants, in salt domes for long-term storage. Violation of the law includes a requirement to remove the radioactive material.
The salt dome ban for radioactive waste remains in effect, but, in 1999, the Legislature exempted oil and gas exploration and production wastes, which includes NORM, from the statutory definition of “radioactive waste,” DEQ officials said.
Prior to that change, NORM fell under the definition of “radioactive waste” and, therefore, was prohibited from salt dome disposal in 1995, DEQ officials said in an email.
DEQ and the state Department of Natural Resources’ Office of Conservation have dual and sometimes overlapping regulatory authority when it comes to salt domes, oil and gas operations and other matters.
DEQ officials said NORM disposal in a salt dome or a well requires concurrence from DNR and DEQ.
In Aug. 31, 1995, letter, James Welsh, then director of the Office of Conservation’s Injection and Mining Division, gave Texas Brine a no objection letter for NORM disposal in a salt dome. Welsh is now commissioner of the Office of Conservation, which leads DNR’s oversight of the Texas Brine cavern failure.
DNR spokesman Patrick Courreges said the no objection letter for NORM disposal did not authorize its disposal in the salt dome because the Office of Conservation does not have regulatory authority.
“The letter communicated to the company that the Office of Conservation’s governing statutes and rules contained no prohibition for the activity and that the Office of Conservation did not regulate NORM activities,” Courreges wrote.
Courreges wrote that the Office of Conservation regulations apply to “the mechanics of safely operating the well and cavern” but NORM falls under DEQ regulations.
In a subsequent, Sept. 20, 1995, letter, Texas Brine Environmental, Health and Safety Manager Scott Whitelaw asked DEQ for authority to dispose of NORM in the salt dome caverns.
DEQ’s Mallett said that no formal denial letter is in agency records but telephone logs show that DEQ officials told the company it was not granting authority and to wait on disposal.
“In our records, they never asked again,” he said.
On Aug. 10 in Ascension Parish, Bruce Martin, vice president of Texas Brine operations, said a small amount of pipe scale had fallen outside of the Oxy Geismar No. 3 well head during workovers.
Scientists have said they believe the Napoleonville Dome cavern — now known as Oxy Geismar Well No. 3 — had a major wall failure that resulted in the sinkhole and in the release of oil and methane in the Grand Bayou and Bayou Corne areas, which have been evacuated.
Testing of the pipe scale found the dirt had a radioactivity of 20 to 40 micro-rems per hour, Martin said.
The standard at the time for specialized management of the NORM was above 20 micro-rems per hour, though that standard has since been raised to 50 micro-rems per hour, Martin said.
“So the end result is, we submitted a request to DNR to place this material, this normally occurring radioactive material, that was actually about a little bit less than a cubic yard, to place it back in the well where it came from, back into the earth,” Martin said.
“And DNR granted us that request. We did that work. That material was solid dirt, dirt with some NORM in it, and it was placed in the bottom of the well, and it would be my guess and firm belief that that’s where it sits today.”
Talking points distributed that day also said NORM was in the cavern and posed no risk.
Sonny Cranch, spokesman for Texas Brine, said last week that officials “misspoke” then in their attempt to respond to questions about NORM and that it was never put in the cavern.