two hours after collecting the first individual mass sample for the sampling interval

NAF well sections; (2) measured depth (feet) of all NAF well sections; (3) total number of sampling intervals (see Section 2.4 and Section 2.6 of this addendum); (4) number of sampling intervals tabulated during any zero discharge operations; (5) total volume of zero discharged NAF-cuttings over entire NAF well sections, and (6) identification of whether BMPs were employed (see Addendum B of Appendix 7 of subpart A of this part).

ADDENDUM B TO APPENDIX 7 TO SUBPART A OF

PART 435—BEST MANAGEMENT PRACTICES (BMPs) FOR USE WITH API RECOMMENDED PRACTICE 13B-2

3.6 Operators shall not discharge any sample before successfully completing the mass and retort analyses [i.e., mass balance requirements (see Section 4.b, Appendix 7 of subpart A of this part) are satisfied). Operators shall immediately re-run the retort analyses if the mass balance requirements (see Equation 4, Appendix 7 of subpart A of this part) are not within a tolerance of 5% (see Section 4.b, Equation 4, Appendix 7 of subpart A of this part).

4.0 CALCULATIONS 4.1 Operators shall calculate a set of mass percent NAF base fluid retained on cuttings values (%BF) and mass NAF-cuttings discharge fractions (X) for each NAF-cuttings waste stream (see Section 1.1 of this addendum) for each sampling interval (see Section 2.4 of this addendum) using the procedures outlined in Appendix 7 of subpart A of this part.

4.2 Operators shall tabulate the following data for each individual NAF-cuttings sample: (1) Date and time of NAF-cuttings sample collection; (2) time period of NAFcuttings sample collection (see Section 3.1 of this addendum); (3) mass and volume of each NAF-cuttings sample; (4) measured depth (feet) at NAF-cuttings sample collection (see Section 2.2 of this addendum); (5) respective linear feet of hole drilled represented by the NAF-cuttings sample (feet); and (6) the drill bit diameter (inches) used to generate the NAF-cuttings sample cuttings.

4.3 Operators shall calculate a single total mass percent NAF base fluid retained on cuttings value (%BFT) for each sampling interval (see Section 2.4 of this addendum) using the procedures outlined in Appendix 7 of Subpart A of this part.

4.4 Operators shall tabulate the following data for each total mass percent NAF base fluid retained on cuttings value (%BFT) for each NAF-cuttings sampling interval: (1) Date and starting and stopping times of NAF-cuttings sample collection and retort analyses; (2) measured depth of well (feet) at start of NAF-cuttings sample collection (see Section 2.2 of this addendum); (3) respective linear feet of hole drilled represented by the NAF-cuttings sample (feet); (4) the drill bit diameter (inches) used to generate the NAFcuttings sample cuttings; and (5) annotation when zero discharge of NAF-cuttings is performed.

4.5 Operators shall calculate the weighted mass ratio averaged over all NAF well sections (%BFwell) using the procedures outlined in Appendix 7 of Subpart A of this part. 4.6 Operators shall tabulate the following data for each weighted mass ratio averaged over all NAF well sections (%BFwell) for each NAF well: (1) Starting and stopping dates of

1.0 OVERVIEW OF BMPS 1.1 Best Management Practices (BMPs) are inherently pollution prevention practices. BMPs may include the universe of pollution prevention encompassing production modifications, operational changes, material substitution, materials and water conservation, and other such measures. BMPs include methods to prevent toxic and hazardous pollutants from reaching receiving waters. Because BMPs are most effective when organized into a comprehensive facility BMP Plan, operators shall develop a BMP in accordance with the requirements in this addendum.

1.2 The BMP requirements contained in this appendix were compiled from several Regional permits, an EPA guidance document (i.e., Guidance Document for Developing Best Management Practices (BMP)" (EPA 833-B-93-004, U.S. EPA, 1993)), and draft industry BMPs. These common elements represent the appropriate mix of broad directions needed to complete a BMP Plan along with specific tasks common to all drilling operations.

1.3 Operators are not required to use BMPs if all NAF-cuttings discharges are monitored in accordance with Appendix 7 of Subpart A of this part.

2.0 BMP PLAN PURPOSE AND OBJECTIVES 2.1 Operators shall design the BMP Plan to prevent or minimize the generation and the potential for the discharge of NAF from the facility to the waters of the United States through normal operations and ancillary activities. The operator shall establish specific objectives for the control of NAF by conducting the following evaluations.

2.2 The operator shall identify and document each NAF well that uses BMPs before starting drilling operations and the anticipated total feet to be drilled with NAF for that particular well.

2.3 Each facility component or system controlled through use of BMPs shall be examined for its NAF-waste minimization opportunities and its potential for causing a discharge of NAF to waters of the United States due to equipment failure, improper

con

3.0 BMP PLAN REQUIREMENTS 3.1 The BMP Plan may reflect requirements within the pollution prevention requirements required by the Minerals Management Service (see 30 CFR 250.300) or other Federal or State requirements and incorporate any part of such plans into the BMP Plan by reference.

3.2 The operator shall certify that its BMP Plan is complete, on-site, and available upon request to EPA or the NPDES Permit controlling authority. This certification shall identify the NPDES permit number and be signed by an authorized representative of the operator. This certification shall be kept with the BMP Plan. For new or modified NPDES permits, the certification shall be made no later than the effective date of the new or modified permit. For existing NPDES permits, the certification shall be made within one year of permit issuance.

3.3 The BMP Plan shall:

3.3.1 Be documented in narrative form, and shall include any necessary plot plans, drawings or maps, and shall be developed in accordance with good engineering practices. At a minimum, the BMP Plan shall contain the planning, development and implementation, and evaluation/reevaluation components. Examples of these components are contained in “Guidance Document for Developing Best Management Practices (BMP)” (EPA 833-B-93-004, U.S. EPA, 1993).

3.3.2 Include the following provisions concerning BMP Plan review.

3.3.2.1 Be reviewed by permittee's drilling engineer and offshore installation manager (OIM) to ensure compliance with the BMP Plan purpose and objectives set forth in Section 2.0.

3.3.2.2 Include a statement that the review has been completed and that the BMP Plan fulfills the BMP Plan purpose and objectives set forth in Section 2.0. This statement shall have dated signatures from the permittee's drilling engineer and offshore installation manager and any other individuals responsible for development and implementation of the BMP Plan.

3.4 Address each component or system capable of generating or causing a release of significant amounts of NAF and identify spe

cific preventative or remedial measures to be implemented.

4.0 BMP PLAN DOCUMENTATION 4.1 The operator shall maintain a copy of the BMP Plan and related documentation (e.g., training certifications, summary of the monitoring results, records of NAF-equipment spills, repairs, and maintenance) at the facility and shall make the BMP Plan and related documentation available to EPA or the NPDES Permit controlling authority upon request.

5.0 BMP PLAN MODIFICATION 5.1 For those NAF wastestreams trolled through BMPs, the operator shall amend the BMP Plan whenever there is a change in the facility or in the operation of the facility which materially increases the generation of those NAF-wastes or their release or potential release to the receiving waters.

5.2 At a minimum the BMP Plan shall be reviewed once every five years and amended within three months if warranted. Any such changes to the BMP Plan shall be consistent with the objectives and specific requirements listed in this addendum. All changes in the BMP Plan shall be reviewed by the permittee's drilling engineer and offshore installation manager.

5.3 At any time, if the BMP Plan proves to be ineffective in achieving the general objective of preventing and minimizing the generation of NAF-wastes and their release and potential release to the receiving waters and/or the specific requirements in this addendum, the permit and/or the BMP Plan shall be subject to modification to incorporate revised BMP requirements. 6.0 SPECIFIC POLLUTION PREVENTION RE

QUIREMENTS FOR NAF DISCHARGES ASSOCIATED WITH CUTTINGS

6.1 The following specific pollution prevention activities are required in a BMP Plan when operators elect to control NAF discharges associated with cuttings by a set of BMPs.

6.2 Establishing programs for identifying, documenting, and repairing malfunctioning NAF equipment, tracking NAF equipment repairs, and training personnel to report and evaluate malfunctioning NAF equipment.

6.3 Establishing operating and maintenance procedures for each component in the solids control system in a manner consistent with the manufacturer's design criteria.

6.4 Using the most applicable spacers, flushes, pills, and displacement techniques in order to minimize contamination of drilling fluids when changing from water-based drilling fluids to NAF and vice versa.

6.5 A daily retort analysis shall be performed (in accordance with Appendix 7 to

Subpart B [Reserved]

Subpart C-Onshore Subcategory

as

$ 435.30 Applicability; description of

the onshore subcategory. The provisions of this subpart are applicable to those facilities engaged in the production, field exploration, drilling, well completion and well treatment in the oil and gas extraction industry which are located landward of the inner boundary of the territorial seas as defined in 40 CFR 125.1(gg) and which are not included within subpart D, E, or F, Provided, however, That the applicability of this subpart to (a) facilities in existence on April 13, 1979 or thereafter engaged in the production, field exploration, drilling, well completion and well treatment in the oil and gas extraction industry which are located on land and which would have been considered “coastal" as defined under the interim final regulations for this industry (40 CFR 435.41, 41 FR 44942, October 13, 1976) or which are (b) located in the Santa Maria Basin of California is suspended. (Secs. 301, 304(b) and 501 of the Clean Water Act as amended, 33 U.S.C. 1251 et seq.) (44 FR 22075, Apr. 13, 1979, as amended at 47 FR 31555, July 21, 1982]

$ 435.32 Effluent limitations guidelines

representing the degree of effluent reduction attainable by the applica. tion of the best practicable control

technology currently available. Except provided in $$ 125.30 through 125.32, any existing point source subject to this subpart shall achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT): there shall be no discharge of waste water pollutants into navigable waters from any source associated with production, field exploration, drilling, well completion, or well treatment (i.e., produced water, drilling muds, drill cuttings, and produced sand). [60 FR 33966, June 29, 1995)

$ 435.31 Specialized definitions.

For the purpose of this subpart:

(a) The general definitions, abbreviations, and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

or

(b)(1) Any location landward from the inner boundary of the territorial seas

West, 89 48 West, 90-12 West, 90 20 West 90°35' West. 90°43 West, 90-57 West, 91 02 West, 91 14' West, 91-27 West, 91 33 West. 91 46' West. 9150 West. 91 56 West, 92 10 West. 92 55' West. 93 15' West, 93 49 West, 94 03 West, 94 10 West, 94 20 West. 95 00 West, 95 13 East, 95 08 West. 95°11' West. 95 22 West. 95 30 West 95 33 West. 9540 West, 96 42 East. 96 40 West, 96 54' West, 97 03 West, 97 15' West. 97 40 West, 97 46' West, 97 51' East. 97 46' East. 97 30 East, 97 26

North, 29°50' North, 30°06' South, 29°35'. South, 29°30'. South, 29 25'. North, 29°32 North, 29°40'. South, 29°32'. North, 29 37'. North, 29°46' North, 29 50. North, 29 55'. South, 29 50'. South, 29°44'. North, 29 46' North, 30°14'. South, 30°07'. South, 30°03'. South, 30 00'. South, 29 53'. South, 29 35'. South, 29 28'. South, 29° 15' South, 29 08 South, 28 56'. South, 28°55'. South, 28 49'. South, 28°47'. South, 28°41'. South, 28 28'. South, 28 20' South, 28°13'. South, 27 58' South, 27°45'. South, 27 28 South, 27 22'. South, 27°14'. South, 26°30'. South, 26°11',

troleum Institute Recommended Practice 13B-2 supplemented with the specifications, sampling methods, and averaging method for retention values provided in Appendix 7 of subpart A of this part.

(e) Biodegradation rate as applied to BAT effluent limitations and NSPS for drilling fluids and drill cuttings refers to the ISO 11734:1995 method: “Water quality-Evaluation of the ultimate' anaerobic biodegradability of organic compounds in digested sludge—Method by measurement of the biogas production (1995 edition)" (Available from the American National Standards Institute, 11 West 42nd Street, 13th Floor, New York, NY 10036) supplemented with modifications in Appendix 4 of subpart A of this part.

(f) Cook Inlet refers to coastal locations north of the line between Cape Douglas on the West and Port Chatham on the east.

(g) Daily values as applied to produced water effluent limitations and NSPS means the daily measurements used to assess compliance with the maximum for any one day.

(h) Deck drainage means any waste resulting from deck washings, spillage, rainwater, and runoff from gutters and drains including drip pans and work areas within facilities subject to this Subpart.

(i) Development facility means any fixed or mobile structure subject to this Subpart that is engaged in the drilling of productive wells.

(j) Dewatering effluent means wastewater from drilling fluids and drill cuttings dewatering activities (including but not limited to reserve pits or other tanks or vessels, and chemical or mechanical treatment occurring during the drilling solids separation/recycle/disposal process).

(k) Diesel oil refers to the grade of distillate fuel oil, as specified in the American Society for Testing and Materials Standard Specification for Diesel Fuel Oils D975–91, that is typically used as the continuous phase in conventional oil-based drilling fluids. This incorporation by reference approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from the American Society

(2) East to 97°19' West Longitude and Southward to the U.S.-Mexican border.

$ 435.41 Specialized definitions. For the purpose of this subpart:

(a) Except as provided below, the general

definitions, abbreviations and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

(b) Average of daily values for 30 consecutive days means the average of the daily values obtained during any 30 consecutive day period.

(c) Base fluid means the continuous phase or suspending medium of a drilling fluid formulation.

(d) Base fluid retained on cuttings as applied to BAT effluent limitations and NSPS refers to the American Pe

was