01-31176. Notice of Final NPDES General Permit; Final NPDES General Permit for New and Existing Sources and New Dischargers in the Offshore Subcategory of the Oil and Gas Extraction Category for the Western Portion of the Outer Continental Shelf of ...

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice.

SUMMARY:

EPA Region 6 today issues a modification of the National Pollutant Discharge Elimination System (NPDES) general permit for the Western Portion of the Outer Continental Shelf of the Gulf of Mexico (No. GMG290000) for discharges from new sources, existing sources, and new dischargers in the Offshore Subcategory of the Oil and Gas Extraction Point Source Category (40 CFR part 435, subpart A). The modified permit will become effective February 19, 2002. The existing permit published in the Federal Register, at 64 FR 19156 on April 19, 1999, authorizes discharges from exploration, development, and production facilities located in and discharging to Federal waters of the Gulf of Mexico seaward of the outer boundary of the territorial seas offshore of Louisiana and Texas. Today's action adds the authorization to discharge of drill cuttings generated using synthetic and other non-aqueous based drilling fluids and hydrostatic test water form pressure testing of existing pipelines.

A copy of the Region's responses to comments and the final permit may be obtained from the EPA Region 6 internet site: http://www.epa.gov/​earth1r6/​6wq/​6wq.htm.

FOR FURTHER INFORMATION CONTACT:

Ms. Diane Smith, EPA Region 6, 1445 Ross Avenue, Dallas, Texas 75202, Telephone: [phone], or via EMAIL to the following address: [e-mail].

SUPPLEMENTARY INFORMATION:

Regulated Entities. Entities potentially regulated by this action are those which operate offshore oil and gas extraction facilities located in the Outer Continental Shelf Offshore of Louisiana and Texas.

Category	Examples of regulated entities
Industry	Offshore Oil and Gas Extraction Platforms.

This table lists the types of entities that EPA is now aware could potentially be regulated by this action. Other types of entities not listed in the table could also be regulated. To determine whether your (facility, company, business, organization, etc.) is regulated by this action, you should carefully examine the applicability criteria in Part I. Section A.1. of the general permit. If you have questions regarding the applicability of this action to a particular entity, consult the person listed in the preceding FOR FURTHER INFORMATION CONTACT section.

Pursuant to section 402 of the Clean Water Act (CWA), 33 U.S.C. 1342, EPA proposed and solicited comments on NPDES general permit GMG290000 at 63 FR 2238 (January 14, 1998). Notice of this proposed permit modification was also published in the New Orleans Times Picayune and the Lafayette Daily Advisor on June 9, 2001. The comment period closed on August 6, 2001.

Region 6 received comments from the Offshore Operators Committee, M-I LLC, Baroid Drilling Fluids, Petro-Canada, and B.P. Chemicals.

EPA Region 6 has considered all comments received. In response to those comments, protocol were included in the final permit for the new test methods for sediment toxicity and biodegradation. A statistical tool was also included in the final permit to account for variability in those new test methods. Several clarifications were also made in the permit's language.

The permit modification includes limits and monitoring requirements for six new parameters. Monitoring for those parameters and implementation of the required test methods have not previously been required for offshore oil and gas discharges. Industry is therefore expected to need some time to get the necessary equipment in place and train personnel prior to beginning the monitoring. The effective date of the permit is being delayed by thirty days to accommodate those needs.

EPA also expects that many operators will not be able to comply with several of the permit's new limits on the effective date. Operators may be unable to get new equipment in place to meet the new limits for retention of drilling fluid on drill cuttings. There may be an insufficient stock of synthetic base fluids which comply with the new limits. Also, time will be needed to complete the 275 day biodegradation test and to develop sufficient laboratory capacity and stocks of organisms to conduct the sediment toxicity test. For those reasons administrative compliance orders are being issued requiring those discharges not in compliance with the new limitations to comply within six months.

The industry has requested an additional delay in the compliance requirements for the 4-day sediment toxicity limit until February 1, 2003. There are several complicating factors that will initially make compliance with the limit more difficult than with the stock base fluid sediment toxicity limit. Since the 4-day sediment toxicity test is used to measure toxicity of discharged drilling fluids, not just stock base fluids, components and additives to the drilling fluids will initially make compliance with the limits more difficult. The four day test has been shown to have more inherent variability than the ten day test. Also, demand on laboratories conducting the four day test will be much greater than for the ten day test; thus, there is more of a need to build laboratory capacity and develop an adequate supply of test organisms. The administrative compliance order will therefore require operators to comply with the 4-day sediment toxicity limit by February 1, 2003.

Sam Becker,

Acting Director, Water Quality Protection Division, Region 6.