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Through meetings with Lake Peigneur residents, Jefferson Island Storage & Hub (JISH) newsletters, area newspaper ads, local radio commercials, press interviews and announcements, governmental presentations and community Open House gatherings, JISH has provided information about our proposed expansion.
Here are questions that have been raised regarding JISH and the proposed expansion. If you have other questions, please send an email. We will be glad to hear from you.
Question: Could what happened recently in Daisetta, T exas with a sinkhole forming over a salt dome happen at Lake Peigneur? Do your operations make it more likely to occur?
Answer: It is difficult to discuss any implications of the sinkhole in Daisetta, Texas since no specific cause has been determined. There are no natural gas storage caverns at that Texas salt dome.
Sinkholes are found worldwide and are very often a naturally occurring phenomenon. The existence of Lake Peigneur itself is a result of land subsidence in the area of the salt dome. This is a naturally occurring phenomenon, but in geologic time likely took hundreds of years to develop. Sinkholes have been known to develop over salt domes like the one in Texas as groundwater can dissolve the underlying salt just below the surface over time.
We conduct exhaustive engineering studies in the design of the facilities such as geologic mapping and hydrogeology studies to ensure the suitability of the area for development of gas storage caverns. The caverns are designed, permitted and built based on specific engineering standards and procedures. Many years of experience in the industry guide the selection and construction of natural gas storage caverns, as do federal and state regulatory requirements. Salt dome storage caverns are contained deep within the heart of the salt dome, 3,000 to 5,000 feet below the surface.
As far as brine disposal wells, there has been no definitive link made between the Texas sinkhole and wells. At JISH, our brine disposal well is located 1 mile away from the salt dome, not adjacent to it as is the case at Daisetta (200 feet). We inject the water thousands of feet deep where it won’t affect the surface or groundwater.
Our project plans were developed by engineering and geologic experts to make sure such issues were adequately addressed, and then the plans were extensively reviewed by the appropriate regulatory bodies before we were issued our permits. We carefully monitor subsidence at the sites, both during construction and into the operational phase as an added precaution.
JISH conducts annual and 5-year monitoring of the wells and wellheads for safety, stability and integrity. Regular monitoring of wellhead elevations ensure that any change is detected. If any elevation change were detected, the Louisiana DNR would be notified for investigation. Should subsidence in the area occur, the wells would be blocked-in using the wellhead valves or gas transfers would occur as the DNR and JISH determine based on the specific circumstances. We take subsidence readings twice a year at JISH and haven’t observed any impact.
Question: On April 17, 2008, The Louisiana Senate Natural Resources Committee voted against SB 194, which would have blocked expansion of natural gas storage caverns at Lake Peigneur. What was AGL Resources’ position on this legislation?
Answer: AGL Resources testified that the bill would set a dangerous precedent by stripping the authority to regulate natural gas storage operations from the Department of Natural Resources, the state agency charged with protecting the public and the environment.
The company also countered claims by opponents of expansion that the expansion would harm local water supplies. Tim Goodson, AGL Resources director of safety and environmental health, said "the Chicot Aquifer is a healthy aquifer that's not in dire straits in any way." That argument was backed by Department of Natural Resources and Department of Conservation officials who testified that the impact on groundwater by AGL Resources expansion would be “negligible”.
Question: What was the outcome of the state investigation into the January 29th, 2008, gas release incident?
Answer: Agents from the Department of Natural Resources Office of Conservation inspected the facility March 18, and issued a report of their findings on March 27, 2008. According to the report, all systems at the Jefferson Island Storage and Hub operated correctly following the January 29th power outage, and the incident was not a danger to the surrounding area.
"The Office of Conservation agents found that the facility's blowdown system performed as designed and further, did not find any apparent probable violations pertaining to the event. There were no damages or apparent harmful impacts from the incident," Commissioner of Conservation James Welsh wrote in a letter accompany the report.
Question: With several instances of “foaming” events being tested at Lake Peigneur recently, are there any new theories being explored of their cause?
Answer: Yes. With more samples being gathered, and more testing being performed, the Louisiana Department of Natural Resources (DNR) is exploring the possibility that the “foaming” reported to be seen on Lake Peigneur may actually be caused by preservatives applied by a nearby seafood processing plant. The preservatives create substantial foaming which subsequently enters the lake depending on the direction of winds and tidal currents. The U.S. Geological Survey (USGS) is conducting more testing to determine if this is in fact the cause, but it is one scenario that is being investigated.
Question: On Tuesday, January 29, the media reported a loud noise heard by local residents coming from the JISH facility. What was it?
Answer: That evening, there was a local power outage caused when a vehicle struck a utility pole, which knocked out power to the JISH facility and the surrounding area. As a result, the safety systems at JISH worked as designed following such an incident. This resulted in a minor release of gas from the plant pipes lasting about three minutes and heard by residents in the immediate vicinity.
The release was a result of a reduction of air pressure in the plant control systems following the commercial power outage. The air pressure holds the plant safety valves in the normal, closed position to prevent gas release. When the air pressure reaches a low pressure setpoint, several valves move to the open position, as designed, resulting in a release of gas. Other valves close to isolate the plant process. The gas that was released was gas that was confined to the isolated plant piping. The incident was reported to the State Police and there were no concerns for public safety.
Question: I saw a news story on KLFY-TV 10 that stated that the bubbles at Lake Peigneur are explosive and that there have been fish kills. Is that true?
Answer: The news story that recently aired on KLFY-TV (Channel 10) had a number of mistakes and inaccuracies:
Error # 1: The reporter stated that the USGS found, “the bubbles are explosive, but natural.” The federal agency investigating, USGS, has never indicated that “the bubbles are explosive.” The USGS indicated in their report that the bubble sample was about 70% methane by volume. The percent of methane in the air once the bubbles break at the surface will be much lower. Therefore, there is nothing in these tests, nor in our tests for the same bubbling event, to indicate a combustible mixture, since methane will not ignite at that volume. There is also nothing to suggest pressure pushing naturally occurring methane to the surface since it is lighter than air and will always rise.
Error # 2: The reporter indicated that, “the random explosions have killed a number of fish.” What we do know is that there has not been any such random explosions reported, nor any fish kills as a result.
Error # 3: The reporter indicated that, “the fish have been tested and the reason of their death was inconclusive.” Neither AGL nor the agencies involved in investigating reports of bubbling at the lake (DNR,DEQ and USGS) have conducted testing of dead fish reported to be from “random explosions.”
Error # 4: The reporter indicated that, “Lake Peigneur is unpredictable and creating new salt mines could potentially lead to a natural disaster.” AGL Resources is not creating (nor “drilling,” as also mentioned in the report), for new salt mines. We have proposed an expansion of two additional underground salt storage caverns which will be constructed almost one mile beneath a very “predictable” Lake Peigneur.
We continue to stress that every test conducted by the state and federal agencies, as well as our own company, continue to show that there is absolutely no connection between our operations and the reported bubbling. Even though testing continues to eliminate our gas storage caverns as a source of the bubbling, we will continue to assist the investigating authorities to determine a cause.
While the USGS did not release any conclusions with its raw data on the samples it took at the lake, it is clear that representatives from the Save Lake Peigneur group are significantly misrepresenting the test results. There is nothing in the results to indicate a combustible mixture since methane will not ignite at that concentration. There is also nothing to suggest pressure pushing naturally occurring methane to the surface since it is lighter than air and will always rise.
Question: In December 2007, the media reported that the Save Lake Peigneur group claimed tests, conducted by the United States Geological Survey (USGS), show the reported bubbling in the lake could be explosive. Is this true?
Answer: That is not true. While the USGS did not release any conclusions with its raw data on the samples it took at the lake, there is nothing in the results to indicate a combustible mixture since methane will not ignite at that volume. There is also nothing to suggest pressure pushing naturally occurring methane to the surface since it is lighter than air and will always rise. The USGS tests are consistent with naturally-occurring methane, at levels that could not possibly ignite or explode.
Every test conducted thus far by the state and federal agencies, as well as our own company, continue to show that there is absolutely no connection between our operations and the reported bubbling. Even though testing continues to eliminate our gas storage caverns as a source of the bubbling, we will continue to assist the investigating authorities to determine a cause.
Question: Did AGL Resources collect and test samples from the same bubbling event that USGS tested? If so, what did your results show?
Answer: Yes. AGL Resources collected samples from the October 26th bubbling event and sent them to an independent laboratory for testing. Although the sampling and analytical method differed from the type conducted by the USGS, the results were the same in that in this event, they pointed to naturally occurring methane. There was no presence of ethane, which is a common component of pipeline quality natural gas.
Question: 80 years of salt mining, sulfur mining and oil and gas exploration activity may have created pollutants that are safely buried on the bottom of Lake Peigneur. Won’t dredging stir up sediment containing these pollutants and contaminate the lake?
Answer: The Louisiana Department of Natural Resources (DNR) has conducted tests, including sending divers to inspect and sample sediments at the bottom of the lake. DNR officials reported their analysis showed the water in the lake is clean and there were no detected hazards. Testing performed by an independent firm also confirms there is no environmental danger present in sediment on the lake bottom in the area that would be dredged.
Question: How long have salt caverns been used to store natural gas and how many exist today?
Answer: Underground storage of natural gas has been utilized since the early 1900’s. In 1961, Southeastern Michigan Gas Company used the first salt cavern for storing gas from a cavern originally developed by Morton Salt Company for salt production. The first caverns designed specifically for natural gas storage in salt dome structures were constructed in Covington County, Mississippi. Today there are over 2,000 caverns utilized for storage of hydrocarbons and approximately 200 are used for natural gas storage.
Question: Have any tests been conducted to confirm the structural integrity of the salt structure at Lake Peigneur and, if so, what did they find?
Answer: Sonar images taken in the caverns during the initial mechanical integrity test, and follow-up tests, show no evidence of any slabbing or fracturing and the integrity of the salt has not been compromised. In a report by Dr. Brian Lock, a noted Professor of Geology at the University of Louisiana-Lafayette, prepared in the summer of 2007, Dr. Lock says core samples he has seen, as well as the core lab reports prepared December 14, 1994, when the existing JISH storage caverns were created, indicate relatively normal salt. Dr. Lock says, “Normal salt from every Gulf Coast dome will show impurities of a few percent of anhydrite (calcium sulfate), sand (less than three percent weight in two of ten samples) and trace amounts of clay that can be visible.” He further says, “The core I saw was strong and intact rock,” and concludes, “there are no indications of inherent weakness or other potential fracturing, granulation, friability, etc.”
Question: Is it possible a “Shear Zone” may be causing the salt structure under Lake Peigneur to be unstable?
Answer: “Shear zones” or, more accurately, anomalous zones in general, are in most respects just like “ordinary” salt. The crystals may be larger and the rock may be darker, but salt heals very quickly—in a matter of months, in some cases. Any fracture is quickly healed and the healed salt is not only just as impermeable as regular salt, it is also commonly harder. This is similar to a cut or wound on a person’s body that heals with scar tissue that is thicker and tougher than the original skin.
Question: In the past two years some people have noticed “bubbling or foaming” in the lake. Is the “bubbling” or “foaming” at Lake Peigneur caused by “gassy salt” dissolving along the surface of the lake?
Answer: There is no known cause for the bubbling or foaming events that have taken place periodically at Lake Peigneur over the past two years. We are convinced that there is no connection between any reported bubbling or foaming activity at Lake Peigneur and our facility.
The DNR has conducted tests, including divers inspecting and sampling sediments at the bottom of the lake. DNR officials reported their analysis showed the water in the lake is clean and there were no detected hazards. While their investigation did not conclude a cause for the bubbling or foaming, it did determine that there is no condition suggesting cause for concern. The Louisiana Department of Environmental Quality (DEQ) has looked into the bubbling or foaming issue and has not determined the cause. None of the state or federal agencies involved in trying to track the causes of the bubbling or foaming indicates there is a connection to JISH operations.
Our company has also performed extensive testing and monitoring of our facilities and the storage caverns and has found nothing that could be causing the bubbling or foaming. The two existing caverns have been operating safely since they were developed in 1994.
AGL Resources is continuing to assist state agencies in their efforts to determine the cause of the bubbling or foaming.
Question: Is it likely that natural gas in the two existing storage caverns may be escaping and causing the “bubbling or foaming” during pressure brought on during cold weather months?
Answer: The pressure data for the caverns has been closely reviewed, both internally by AGL Resources on-site at the JISH plant and by the DNR personnel. The pressure data shows there is no correlation to the reported bubbling or foaming events. On a given day, a very slight change in pressure in caverns might go unnoticed. According to Dr. Brian Lock, Professor of Geology at the University of Louisiana-Lafayette, “for this [loss of pressure] to have been occurring over a period of two years and go unnoticed is not possible.”
Question: Can gas from the JISH caverns make its way into the salt mines and escape through boreholes left behind by the mining operations?
Answer: There is no evidence that gas is leaving the JISH caverns except through the normal channels (pipelines running between the caverns and the compressor station). Thus, there would be no way for gas from the caverns to reach these boreholes. In addition, according to Dr. Lock, salt heals quickly and salt creep will have closed all boreholes from the old mine caverns years ago.
Question: What is the likelihood drilling new salt dome caverns could create another event such as the one when Lake Peigneur drained into a salt mine?
Answer: There is no likelihood of a similar event occurring. More than 25 years ago, a contractor for a major oil company was drilling exploration wells for oil and gas and penetrated horizontal shafts of active salt mines. Today those shafts and tunnels are filled below Lake Peigneur with water and sediment. There is no other place for the water to go.
Question: How does the amount of water required for drilling the salt dome caverns compare to other uses of water from the Chicot Aquifer?
Answer: Within a five-mile radius of the center of Lake Peigneur there are a total of 50 registered wells: 31 in Vermilion Parish and 19 in Iberia Parish. Some existing area wells use twice the annual water volume as the amount proposed by JISH for its cavern development. The JISH withdrawal is roughly the equivalent to the daily withdrawal rate of two to three existing agricultural irrigation or typical industrial wells.
Unlike other agricultural and industrial users who will pump groundwater for the life of their projects, the pumping of groundwater for JISH from the Chicot Aquifer will occur only during the four-year construction period. An independent engineering firm, URS Corporation of Baton Rouge, performed an analysis of the impact of the process on the Chicot Aquifer and confirms the aquifer has an abundant supply of water, which will not be compromised by the cavern development.
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