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Preparation of a Programmatic Environmental Assessment for Applications To Inject Outer Continental Shelf (OCS) Generated, Resource Conservation and Recovery Act (RCRA) Exempt Exploration and Production (E&P) Waste Into Salt Caverns and Caprock on Sulphur and Salt Lease OCS-G 9372, Main Pass Block 299

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Minerals Management Service, Interior.


Preparation of an Environmental Assessment and Notice of Public Scoping Meeting.


Minerals Management Service (MMS) is preparing a programmatic environmental assessment (EA) for applications from OCS oil and gas operators to inject OCS-generated, and RCRA-exempt, exploration and production (E&P) waste into salt caverns and caprock at Main Pass Block 299. Main Pass Block 299 is located 16 miles offshore, east of Plaquemines Parish, Louisiana. Water depth at the proposed waste injection site is 210 feet.

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Minerals Management Service, Gulf of Mexico OCS Region, 1201 Elmwood Park Boulevard, New Orleans, Louisiana 70123-2394, Mr. Clay Pilie', telephone (504) 736-2443.

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Freeport-McMoRan Sulphur LLC (Freeport) has presented the MMS Gulf of Mexico (GOM) Region with a detailed proposal to inject OCS-generated, RCRA-exempt E&P waste into the salt caverns and caprock (the rock formation overlying the salt dome, consisting of anhydrite, limestone, and sulphur ore) that underlies the existing Main Pass Block 299 sulphur and salt Lease OCS-G 9372. Start Printed Page 5848RCRA-exempt E&P wastes are wastes from the exploration, development, and production of crude oil, natural gas, and geothermal energy that are exempted from regulation as hazardous wastes under RCRA Subtitle C (53 FR 25477) by a July 6, 1988, U.S. Environmental Protection Agency (EPA) regulatory determination. On March 22, 1993, EPA issued clarification of the 1988 determination (58 FR 15284). Only RCRA-exempt E&P wastes containing naturally occurring radioactive material in concentrations less than 30 picocuries per gram and exposure rates of less than 50 microroentgens per hour inclusive of background are proposed for injection at Main Pass Block 299.

Use of Main Pass Block 299 for E&P waste injection would combine the production of salt (in the form of brine) and the use of the caverns created by salt production (and in the course of sulphur production, which was conducted on the lease) as well as the caprock overlying the salt dome for disposal of waste.

Trinity Field Services, L.P. and Freeport have formed an alliance for the collection, transportation, handling, and disposal of OCS-generated, RCRA-exempt E&P waste. E&P waste will be received in bulk or in cuttings boxes/portable tanks by offshore supply vessel or self-propelled barge at Main Pass Block 299 from single and multiple offshore operating locations where the waste is generated. The waste will be either directly injected or injected after being temporarily stored and processed to extract recyclable materials or to enhance injection capability. In some cases, waste will be processed at existing onshore facilities (Fourchon, Venice, and Berwick/Morgan City, Louisiana) to remove hydrocarbons and/or other recyclable materials (primarily synthetic drilling fluids) and then taken to Main Pass Block 299 for injection.

The Main Pass Block 299 platform complex associated with the proposed waste disposal operations was constructed to support the development and production of sulphur and oil and gas reserves present in the formations above the Main Pass Block 299 salt dome structure. The facility is over a mile in length and is one of the largest structures in the GOM. Both drilling platforms PP1 and PP2 could be used to support the waste disposal activity. New equipment to be installed to accommodate waste injection will consist of a waste pump unit, air compressor, storage tanks, tank cleaning pumps, a tank cleaning vacuum system, waste pumps and dryers, and a waste air compressor, as well as additional piping on the platform. Sulphur production was discontinued in August 2000 due to unfavorable economics attributable to the combined effect of low sulphur prices and high natural gas prices (large volumes of natural gas are required to fire the boilers that heat the water injected into the formation in order to produce the sulphur and power the generators to produce electricity). Oil and gas resources are still being produced from Main Pass Block 299.

If Main Pass Block 299 is used, waste injection activities could span an anticipated 26 years starting in 2002. The anticipated volume of OCS-generated, RCRA-exempt E&P wastes that could be injected at Main Pass Block 299 is estimated to be 119 million barrels. The combined estimated disposal capacity of the caverns and barren/leached caprock is approximately 2.6 billion barrels. Freeport estimates the typical waste streams to be injected would consist of approximately 16 percent solids, 77 percent liquids, and 7 percent hydrocarbons. The EA will analyze information provided by Freeport with respect to disposal into the caprock and salt caverns underlying Main Pass Block 299. Alternatives will include the proposed action with additional mitigations and no action (i.e., disapproval of the applications). The analyses in the EA will examine the potential environmental effects of the activities described by Freeport and alternatives including the potential environmental benefits over current offshore waste management practices. Current offshore waste management practices for E&P wastes that do not meet the standards for overboard discharge in accordance with a National Pollutant Discharge Elimination System (NPDES) permit include onshore disposal or disposal offshore in waste injection wells (in accordance with MMS Notice to Lessees 99-G22). E&P wastes that do meet the standards for overboard discharge in accordance with a NPDES permit are typically discharged into OCS waters.

Prior to considering applications for use of Main Pass Block 299 for waste injection activities, MMS must be assured that all activities will be conducted in an environmentally safe manner, that all injected waste will remain in the caverns and caprock, and that operational activities, monitoring activities, closure procedures, hazards analysis, and safety and environmental plans are in place and found to be acceptable.

In preparation for evaluating the applications, MMS has consulted with the following Federal, State, and private agencies: EPA , National Marine Fisheries Service, U.S. Fish and Wildlife Service, Department of Energy, State of Louisiana, State of Texas, Solution Mining Research Institute, and Sandia National Lab—Underground Storage Technology Department. MMS has also reviewed numerous documents and technical reports (e.g., approval of nonhazardous oil-field waste disposal applications in Texas conducted by the Texas Railroad Commission; Texas Proposed Statewide Rule 82—Cavern Disposal Regulations; Louisiana Draft Regulations, Statewide Order No. 29-M-2, “E&P Waste Disposal in Solution-Mined Salt Caverns''; “Preliminary Technical and Legal Evaluation of Disposing of Nonhazardous Oil Field Waste into Salt Caverns'' (Argonne National Laboratory); “Geologic Site Characterization Requirements for Storage and Mining in Salt” (Sandia Lab); and “An Investigation of the Integrity of Cemented Casing Seals with Application to Salt Cavern Sealing and Abandonment” (Solution Mining Research Institute)).

A public scoping meeting will be held on February 21, 2002, from 1:00 to 3:00 p.m. at the Minerals Management Service, Gulf of Mexico OCS Region, 1201 Elmwood Park Boulevard, Room 111, New Orleans, Louisiana. At the meeting, MMS and Freeport will provide information on the applications and the public will be given an opportunity to ask questions and provide input on issues that should be addressed in the EA. For more information regarding the Main Pass Block 299 waste disposal applications, please visit those documents at:​homepg/​offshore/​mp299/​.

Following completion of the programmatic EA, MMS will either issue a finding of no significant impact or prepare an environmental impact statement.

Public Comments: MMS requests interested parties to submit comments regarding issues that should be addressed in the EA to the Minerals Management Service, Gulf of Mexico OCS Region, Office of Leasing and Environment, Attention: Regional Supervisor (MS 5410),1201 Elmwood Park Boulevard, New Orleans, Louisiana 70123-2394. Comments must be submitted no later than 30 days from the publication of this Notice.

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Dated: February 4, 2002.

Thomas A. Readinger,

Associate Director for Offshore Minerals Management.

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[FR Doc. 02-3009 Filed 2-6-02; 8:45 am]