Current through Register Vol. 50, No. 11, November 20, 2024
Section XVII-315 - Cavern Design and Spacing RequirementsA. This Section provides general standards for design of caverns to ensure that project development can be conducted in a reasonable, prudent, and a systematic manner and shall stress physical and environmental safety. The owner or operator shall continually review the design throughout the construction and operation phases taking into consideration pertinent additional detailed subsurface information and shall include provisions for protection from damage caused by hydraulic shock. If necessary, the original development and operational plans shall be modified to conform to good engineering practices.B. Cavern Spacing Requirements 1. Property Boundary a. Existing Hydrocarbon Storage Caverns. No part of a hydrocarbon storage cavern permitted as of the date these regulations are promulgated shall extend closer than 100 feet to the property of others without consent of the owner(s). Continued operation without this consent of an existing hydrocarbon storage cavern within 100 feet of the property of others may be allowed as follows. i. The operator of the cavern shall make a good faith effort to provide notice in a form and manner approved by the commissioner to the adjacent property owner(s) of the location of its cavern.ii. The commissioner shall hold a public hearing at Baton Rouge if a non-consenting adjacent owner whose property line is within 100 feet objects to the cavern's continued operation. Following the public hearing the commissioner may approve the cavern's continued operation upon a determination that the continued operation of the cavern has no adverse effects to the rights of the adjacent property owner(s).iii. If no objection from a non-consenting adjacent property owner is received within 30 days of the notice provided in accordance with §315.B.1.a.i above, then the commissioner may approve the continued operation of the cavern administratively. b. New Hydrocarbon Storage Caverns. No part of a newly permitted hydrocarbon storage cavern shall extend closer than 100 feet to the property of others without the consent of the owner(s).2. Adjacent Structures within the Salt. As measured in any direction, the minimum separation between walls of adjacent caverns or between the walls of the cavern and any adjacent cavern or any other manmade structure within the salt stock shall not be less than 200 feet. Caverns must be operated in a manner that ensures the walls between any cavern and any other manmade structure maintain the minimum separation of 200 feet. For hydrocarbon storage caverns permitted prior to the effective date of these regulations and which are already within 200 feet of any other cavern or manmade structure within the salt stock, the commissioner of conservation may approve continued operation upon a proper showing by the owner or operator that the cavern is capable of continued safe operations.3. Salt Periphery a. Without exception or variance to these rules and regulations, at no time shall the minimum separation between the cavern walls at any point and the periphery of the salt stock for a newly permitted hydrocarbon storage cavern be less than 300 feet.b. An existing hydrocarbon storage cavern with less than 300 feet of salt separation at any point between the cavern walls and the periphery of the salt stock shall provide the Office of Conservation with an enhanced monitoring plan that has provisions for ongoing monitoring of the structural stability of the cavern and salt through methods that may include, but are not limited to, increased frequency of sonar caliper surveys, vertical seismic profiles, micro-seismic monitoring, increased frequency of subsidence monitoring, mechanical integrity testing, continuous cavern pressure data monitoring, etc. A combination of enhanced monitoring methods may be proposed where appropriate. Once approved, the owner or operator shall implement the enhanced monitoring plan.c. Without exception or variance to these rules and regulations, an existing hydrocarbon storage cavern with cavern walls 100 feet or less from the periphery of the salt stock shall be removed from hydrocarbon storage service immediately and permanently. An enhanced monitoring plan in conformance with §315.B.3.b above for long term monitoring shall be prepared and submitted to the Office of Conservation. Once approved, the owner or operator shall implement the enhanced monitoring plan.d. For hydrocarbon storage caverns in existence as of the effective date of these regulations with less than 300 feet but more than 100 feet of salt separation at any point between the cavern walls and the periphery of the salt stock, continued hydrocarbon storage may be allowed upon submittal of an enhanced monitoring plan in conformance with §315.B.3.b above in addition to any additional maps, studies, tests, assessments, or surveys required by the commissioner to show that the cavern is capable of continued safe operations.C. Cavern Coalescence. The Office of Conservation may permit the use of coalesced caverns for hydrocarbon storage, but only for hydrocarbons that are liquid at standard temperature and pressure. It shall be the duty of the applicant, owner, or operator to demonstrate that operation of coalesced caverns under the proposed cavern operating conditions can be accomplished in a physically and environmentally safe manner and that the stability and integrity of the cavern and salt stock shall not be compromised. The intentional subsurface coalescing of adjacent caverns must be requested by the applicant, owner, or operator in writing and be approved by the Office of Conservation before beginning or resumption of hydrocarbon storage operations. If the design of adjacent caverns should include approval for the subsurface coalescing of adjacent caverns, the minimum spacing requirement of §315. B.2 shall not apply to the coalesced caverns.La. Admin. Code tit. 43, § XVII-315
Promulgated by the Department of Natural Resources, Office of Conservation, LR 40:358 (February 2014), Amended LR 42422 (3/1/2016), Amended LR 482353 (9/1/2022).AUTHORITY NOTE: Promulgated in accordance with R.S. 30:4 et seq.