21548 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 435

[FRL–6581–4]

Effluent Limitations Guidelines for the

Oil and Gas Extraction Point Source

Category

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Proposed Rule; Supplemental

information and notice of meeting.

SUMMARY: On February 3, 1999 (64 FR

5488), EPA proposed technology-based

effluent limitations guidelines and

standards under the Clean Water Act

(CWA) for the discharge of pollutants

from oil and gas drilling operations

associated with the use of syntheticbased drilling fluids (SBFs) and other

non-aqueous drilling fluids into waters

of the United States. This proposed rule

would apply to certain existing and new

facilities in the offshore subcategory

beyond three miles from shore and

offshore of Alaska, and the Cook Inlet,

Alaska, portion of the coastal

subcategory of the oil and gas extraction

point source category.

This document presents a summary of

all data received and collected by EPA

since publication of the proposal; an

assessment of the usefulness of the data

in EPA’s analyses; summary

descriptions of revised engineering and

economic models; and updated

modeling results incorporating the new

data. This notice also discusses ‘‘best

management practices’’ (BMPs) as

potential alternative requirements to

reduce the discharges of toxic and

hazardous pollutants.

DATES: Submit your comments by June

20, 2000. A public meeting will be held

on Tuesday, April 25, 2000, from 1:00

p.m. to 5:30 p.m. Central Standard

Time.

ADDRESSES: Submit comments by mail

to Mr. Carey A. Johnston at the

following address: U.S. Environmental

Protection Agency; Engineering and

Analysis Division (4303); 1200

Pennsylvania Avenue, NW; Washington,

DC 20460. Please submit any references

cited in your comments. EPA would

appreciate an original and two copies of

your comments and enclosures

(including references). Hand delivered

comments may be submitted at the EPA

Headquarters Water Docket (address

below). Comments may also be filed

electronically to

‘‘johnston.carey@epa.gov.’’ Electronic

comments sent to the above e-mail

address will be treated like all other

submitted comments.

The data and analyses being

announced today are available for

review in the EPA Water Docket at EPA

Headquarters at Waterside Mall, Room

EB–57, 401 M. St. SW, Washington, DC

20460. For access to the docket

materials, call (202) 260–3027 between

9:00 a.m. and 4:00 p.m. for an

appointment. A reasonable fee may be

charged for copying.

The public meeting will be held at the

Minerals Management Service (MMS),

Gulf of Mexico OCS Region Office,

Room 111, 1201 Elmwood Park

Boulevard, New Orleans, LA, 70123–

2394.

FOR FURTHER INFORMATION CONTACT: For

additional technical information,

contact Mr. Carey A. Johnston at (202)

260–7186 or at the following e-mail

address: johnston.carey@epa.gov. For

additional economic information

contact Mr. James Covington at (202)

260–5132 or at the following e-mail

address: covington.james@epa.gov.

SUPPLEMENTARY INFORMATION: Visitors

attending the New Orleans public

meeting (see ADDRESSES) will need to

sign in at the MMS guard booth and

obtain a visitors badge. If you wish to

present formal comments at the public

meeting you should have a written copy

for submittal. No meeting materials will

be distributed in advance of the public

meeting; all materials will be distributed

at the meeting. Limited teleconferencing

capability will be available for the

meeting. Persons wishing to participate

via telephone or who have special

audio-visual needs should contact Mr.

Carey A. Johnston, (202) 260–7186.

The Agency invites all parties to

coordinate their data collection

activities with EPA to facilitate

mutually beneficial and cost-effective

data submissions. Please refer to the FOR

FURTHER INFORMATION CONTACT for

technical contacts at EPA.

To ensure that EPA can properly

respond to comments, the Agency

prefers that commenters cite, where

possible, the paragraph(s) or sections in

the notice or supporting documents to

which each comment refers. Please

submit an original and two copies of

your comments and enclosures

(including references).

Commenters who want EPA to

acknowledge receipt of their comments

should enclose a self-addressed,

stamped envelope. No facsimiles (faxes)

will be accepted. Comments and data

will also be accepted on disks in

Wordperfect, ASCII, or Adobe Acrobat

(*.pdf) format.

All comments will be organized by

EPA’s Engineering and Analysis

Division (EAD) and submitted by EAD

to the record supporting this rulemaking

(Docket No. W–98–26) in the EPA Water

Docket. Electronic comments must be

submitted as a Wordperfect, ASCII, or

Adobe Acrobat (*.pdf) format file

avoiding the use of any form of

encryption. Electronic comments must

be identified by the docket number W–

98–26 and may be filed online at many

Federal Depository Libraries. No

confidential business information (CBI)

should be sent via e-mail. EPA’s

information technology services (e.g., email, website) were temporarily shut

down, beginning Thursday, February

17, in order to review and improve

security measures. EPA’s e-mail services

are now operational. However, EPA

recommends that persons submitting

comments electronically call Mr. Carey

A. Johnston, (202) 260–7186, to confirm

EPA receipt.

Contents of This Document

I. Purpose of this Notice

II. Overview of Proposal and Data Acquired

Since the Proposal

III. Revised Models

IV. Revised Analyses

V. Best Management Practices (BMPs)

Alternatives to Numeric Limitations and

Standards

I. Purpose of This Notice

On February 3, 1999 (64 FR 5488),

EPA proposed technology-based effluent

limitations guidelines and standards

under the Clean Water Act (CWA) for

the discharge of pollutants from oil and

gas drilling operations associated with

the use of synthetic-based drilling fluids

(SBFs) and other non-aqueous drilling

fluids into waters of the United States.

This proposed rule would apply to

certain existing and new facilities in the

offshore subcategory (i.e., facilities

seaward of the inner territorial

boundary) and the Cook Inlet, Alaska,

portion of the coastal subcategory of the

oil and gas extraction point source

category.

In this notice, EPA is making new

data submissions available for comment.

Additionally, EPA is providing

descriptions of revised economic and

engineering models incorporating the

new data. Summary descriptions of

updated modeling results are also given

in this notice. This notice also discusses

‘‘best management practices’’ (BMPs) as

potential alternative requirements to

reduce the discharges of toxic and

hazardous pollutants. Finally, this

notice announces that EPA has

submitted an Information Collection

Request (ICR) to the Office of

Management and Budget (OMB) for

these BMP alternatives to numeric

effluent limitations and standards. EPA

solicits public comment on any of the

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21549

issues or information presented in this

notice of data availability and in the

administrative record supporting this

notice.

II. Overview of Proposal and Data

Acquired Since the Proposal

Since about 1990, the oil and gas

extraction industry developed SBFs

with synthetic and non-synthetic

oleaginous (oil-like) materials as the

base fluid to provide the drilling

performance characteristics of

traditional oil-based fluids (OBFs) based

on diesel and mineral oil, but with

lower environmental impact and greater

worker safety through lower toxicity,

elimination of polynuclear aromatic

hydrocarbons (PAHs), faster

biodegradability, lower bioaccumulation

potential, and, in some drilling

situations, less drilling waste volume.

EPA’s information to date, including

limited seabed surveys in the Gulf of

Mexico, indicate that the effect zone of

the discharge of certain SBFs is within

a few hundred meters of the discharge

point. These surveys also indicate that

the sea floor may significantly recover

in one to two years. EPA believes that

impacts are primarily due to smothering

by the drill cuttings, changes in

sediment grain size and composition

(physical alteration of habitat), and

anoxia (absence of oxygen) caused by

the decomposition of the base fluid. The

benthic smothering and changes in grain

size and composition from the cuttings

are effects that are also associated with

the discharge of water-based drilling

fluids (WBFs) and associated cuttings.

Based on the record to date, EPA finds

that these impacts, which are believed

to be of limited duration, are less

harmful to the environment than the

non-water quality environmental

impacts associated with the option of

prohibiting the discharge of all SBFwastes. Moreover, EPA prefers SBFs

over OBFs as there are operational

accidents that lead to spills and loss of

drilling fluid to the environment.

The proposed rule, published on

February 3, 1999 (64 FR 5488),

identified possible methods to control

SBF discharges associated with cuttings

(SBF-cuttings) in a way that reflects the

appropriate level of technology. EPA

proposed using stock limitations and

standards on the base fluids from which

the drilling fluids are formulated. This

would ensure that substitution of

synthetic and other oleaginous base

fluids for traditional mineral oil and

diesel oil reflects the appropriate level

of technology. In other words, EPA

wants to ensure that only the SBFs

formulated from the ‘‘best’’ base fluids

are allowed for discharge. Parameters

that distinguish the various base fluids

are the PAH content, sediment toxicity,

rate of biodegradation, and potential for

bioaccumulation.

EPA also proposed that SBF-cuttings

should be controlled with discharge

limitations and standards, such as a

limitation on the toxicity of the SBF at

the point of discharge, and a limitation

on the mass (as volume) or

concentration of SBFs discharged. The

latter type of limitation would take

advantage of the solids separation

efficiencies achievable with SBFs, and

consequently minimize the discharge of

organic and toxic components.

Additionally, EPA proposed that SBF

discharges not associated with cuttings

(e.g., incidental spills, accumulated

solids, deck drainage) should meet zero

discharge requirements, as this is the

current industry practice due to the

value of these drilling fluids.

Since proposal, EPA has obtained

additional data and information from

the industry and the Agency’s

continued data collection activities. The

Agency has included these data,

information, and the preliminary results

of EPA’s evaluation in sections III.A

through III.H of the supporting record of

this notice, available for review in the

Water Docket (see ADDRESSES section at

the beginning of this notice).

The industry data submittals are

related to stock limitations and

standards on base fluid (e.g., PAH

content, sediment toxicity,

biodegradation, bioaccumulation),

discharge limitations and standards

(e.g., free oil, formation oil

contamination, retention of SBF on

cuttings), technical performance of

ester-based drilling fluids, subsea

pumping systems, cuttings

microencapsulation systems, best

management practices (BMPs), and

health and safety considerations. The

specific data, information, and

comments provided to EPA are

discussed below in detail.

The Agency’s collected data are

related to stock limitations and

standards (e.g., sediment toxicity and

biodegradation); non-water quality

environmental impacts (NWQI)

including on-shore disposal capacity of

exploration and production wastes and

monetization of air emissions; economic

costs related to deepwater projects;

discharge limitations and standards; and

projected environmental outcomes such

as sediment pore water quality.

EPA will evaluate all analytical data

in the rulemaking record to set

limitations and standards that represent

the appropriate level of technology

using a combination of methods

referenced below. Specifically, for

sediment toxicity and biodegradation

limitations and standards, EPA will

evaluate each of the various sediment

toxicity and biodegradation method test

data for the various synthetic base fluids

against known standards such as diesel.

Moreover, EPA will use all sediment

toxicity and biodegradation data to

assess the ability of each sediment

toxicity and biodegradation method

identified below to discriminate

between different types of synthetic

base fluids and produce consistent

results.

In addition, a list of SBF rulemaking

stakeholder meetings and the respective

minutes can be found in section III.A.(c)

of the rulemaking record.

A. Industry Data Submissions Since

Proposal Publication

1. Sediment Toxicity Test Results and

Revised Methods

In the February 1999 proposal, EPA

set the Best Available Technology

Economically Achievable (BAT) and

New Source Performance Standards

(NSPS) stock limitation for sediment

toxicity as: ‘‘10-day LC50 of stock base

fluid minus 10-day LC50 of C16–C18

internal olefin shall not be less than

zero.’’ [The term ‘‘LC50’’ is used to

identify how much of a substance is

needed to kill half of a group of

experimental organisms in a given time;

a higher LC50 value means the material

is less toxic]. EPA also proposed a

compliance method, American Society

for Testing and Material (ASTM)

method E1367–92, and sediment

preparation procedures for this stock

limitation (Appendix 3 to Subpart A of

Part 435).

In addition to sediment toxicity tests

using ASTM method E1367–92,

industry has recently conducted several

studies using alternative sediment

toxicity test methods including a

method based on determining toxicity to

the mysid shrimp, Mysidopsis bahia, in

a sediment-water interface system. As a

result of this effort, industry has

supplied information on the use of

formulated sediments and the

shortening of the exposure period of

synthetic base fluids to marine

amphipods. EPA proposes to use one of

these methods (i.e., ASTM method

E1367–92 or alternative industry mysid

shrimp sediment toxicity test method)

for: (1) the establishment of an

appropriate sediment toxicity rate stock

limitation in the final rule; and (2) use

as a compliance tool.

Several papers published by M–I

Drilling Fuids, L.L.C. (MIDF) provided

data on the toxicity of the synthetic base

fluid C16–C18 internal olefin (IO) and

21550 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

diesel in formulated sediments as well

as data on the results of tests conducted

with a 96-hour exposure period as

compared to the standard 10-day

exposure as specified in ASTM E1367–

92 (Rabke and Candler, 1998; Rabke and

Candler, 1999; Still, et al., 1999).

This work conducted by MIDF was

done in an effort to increase the

discriminatory power of the test

between the toxicity of synthetic base

fluids and diesel, as well as between the

different synthetic base fluids. MIDF

believes that the longer exposure time

reduces discriminatory power because

the test sediment toxicity becomes a

greater factor relative to the test base

fluid toxicity over time. Therefore, the

test sediment’s toxicity would tend to

normalize and obscure the differences

in toxicities of the test base fluids as test

duration increases. Table II.A.1.1

summarizes the LC50 industry sediment

toxicity data with various drilling fluids

[i.e., diesel, internal olefin (IO), linear

alpha olefin (LAO), poly alpha olefin

(PAO), and ester]. A more complete

review of these procedures and data can

be found in section III.B.(b) of the

rulemaking record.

TABLE II.A.1.1: INDUSTRY LC50 SEDIMENT TOXICITY DATA FOR VARIOUS DRILLING BASE FLUIDS AT TWO DIFFERENT TIME

PERIODS

Drilling base fluid LC50 (mg/Kg) 95% Confidence

interval

Baker Hughes INTEQ-Generated Data

96-Hour Test ............................................................... C14/16/18 IO .............................................................. 4020 2926–8219

C14/16/18/20 IO ......................................................... >5111 NA

C16/18 IO ................................................................... 3515 2726–5215

C14/15/16/17/18 LAO/IO ............................................ 1497 1299–1725

10-Day Test ................................................................ Diesel .......................................................................... 343 297–391

C14/16/18 IO .............................................................. 646 625–1250

C14/16/18/20 IO ......................................................... 1218 1070–1453

C16/18 IO ................................................................... 1464 1172–1681

C14 LAO ..................................................................... 205 187–223

C16 LAO ..................................................................... 407 353–473

C14/15/16/17/18 LAO/IO ............................................ 854 696–1018

C30+PAO ................................................................... 2359 1478–5156

Enhanced Mineral Oil ................................................. 79 37–117

Linear Paraffin ............................................................ 1047 846–1257

Paraffin ....................................................................... 111 101–122

Baroid-Generated Data

96-Hour Test ............................................................... Diesel .......................................................................... 453 416–493

IO ................................................................................ 876 442–1663

LAO ............................................................................ 490 291–924

Ester ........................................................................... >20000 NA

Ester (Low viscosity) .................................................. >20000 NA

10-Day Test ................................................................ Diesel .......................................................................... 230 209–251

IO ................................................................................ 564 447–639

LAO ............................................................................ 338 294–378

Ester ........................................................................... >10000 NA

Ester (Low viscosity) .................................................. 2447 2197–2701

MIDF Drilling-Generated Data

96-Hour Test ............................................................... Diesel .......................................................................... 566 510–629

IO ................................................................................ 3686 2890–4893

Method Reference: EPA February 1999 Proposal (64 FR 5488).

Finally, one commenter on the February 1999 proposal, Baroid Drilling Fluids, provided preliminary sediment toxicity

data for two of its ester-based drilling fluids. The data provided in the comments indicate that both esters may have

lower toxicities than other base fluids (e.g., C16–C18 IO, paraffin, mineral oil, diesel oil). However, EPA data presented

in Table II.B.1.1 indicate that the sediment toxicity of IO and ester are significantly better than other alternative base

fluids.

2. Biodegradation Test Results and Revised Methods

In the February 1999 proposal, EPA set the BAT and NSPS stock limitation for biodegradation rate as: ‘‘percent

stock base fluid degraded at 120 days minus percent C16–C18 internal olefin degraded at 120 days shall not be less

than zero.’’ EPA also proposed a compliance method for this stock limitation (Appendix 4 to Subpart A of Part 435).

Industry stakeholders conducted a series of biodegradation tests for determining biodegradation of SBFs and OBFs

using the method proposed by EPA (Appendix 4). Industry stakeholders also identified alternative analytical biodegradation

methods and used these alternative methods to generate data. EPA solicits comment in this notice on use of these

alternative methods and corresponding data to set biodegradation limitations and standards and compliance methods.

EPA proposes to use one of these methods for: (1) The establishment of an appropriate biodegradation rate stock limitation

in the final rule; and (2) use as a compliance tool. The first analytical test method is the solid-phase degradation

test as EPA proposed in February 1999 (Appendix 4). This method consists of spiking ‘‘clean’’ marine or estuarine

sediment with a base fluid and placing these test samples in exposure tanks filled with seawater. The concentration

of base fluid is measured at regular intervals during the test to monitor the degradation of the base fluid.

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21551

Industry-supplied data using the solid phase test are summarized in Table II.A.2.1.

TABLE II.A.2.1: INDUSTRY SOLID PHASE BIODEGRADATION TEST RESULTS

Elapsed time of test

Percent loss relative to day 0

Olive oil

(percent)

Finagreen

ester

(percent)

Diesel

(percent)

C16–C18

Internal

olefin

Neodene

1518

(percent)

Day 10 ........................................................................................... 84 56 * * *

Day 20 ........................................................................................... 88 59 * * *

Day 45 ........................................................................................... 96 90 ¥2 39 2

Day 110 ......................................................................................... 99 95 22 73 58

Day 186 ......................................................................................... 99 99 55 93 83

Method Reference: EPA February 1999 Proposal (64 FR 5488).

*Not tested.

The second biodegradation method evaluated by industry is the marine anaerobic closed bottle test. This test procedure

places a mixture of SBFs or OBFs, marine sediment, and sea water into a tightly capped clean serum bottle. The

conditions within the closed bottle result in the anaerobic degradation of SBFs or OBFs. The anaerobic processes degrading

the base fluids produce gas. This gas production is monitored as a measure of the degradation process. Industry-supplied

data using the closed bottle test are summarized in Table II.A.2.2.

TABLE II.A.2.2: INDUSTRY MARINE ANAEROBIC CLOSED BOTTLE BIODEGRADATION TEST RESULTS

Elapsed time of test

Cumulative gas production over time (ml)

Olive oil C16–C18 internal olefin

C14–C16 linear alpha

olefin

Synthetic

paraffin C30 Blank control

Day 0 ................................................................................ 0.00 0.00 0.00 0.00 0.00 0.00

Day 5 ................................................................................ 9.29 2.77 3.67 3.32 3.32 3.88

Day 25 .............................................................................. 50.00 8.59 10.00 7.05 6.62 5.99

Day 33 .............................................................................. 103.50 12.50 15.00 10.00 8.00 8.30

Day 67 .............................................................................. 150.41 18.38 22.15 13.67 10.45 11.12

Day 77 .............................................................................. 152.50 22.21 26.46 15.83 12.42 12.28

Day 95 .............................................................................. 160.61 24.60 32.74 18.16 12.18 12.98

Day 113 ............................................................................ 162.88 29.71 42.91 21.14 12.80 13.30

Day 132 ............................................................................ 164.78 39.74 55.50 23.17 13.38 14.01

Day 155 ............................................................................ 169.18 59.00 88.16 27.19 15.42 16.07

Day 194 ............................................................................ 167.74 92.36 114.50 25.82 13.97 14.57

Day 231 ............................................................................ 171.57 104.50 138.22 29.49 17.47 17.63

Day 271 ............................................................................ 175.58 119.88 151.20 33.33 21.63 22.11

Method Reference: ISO 11734: ‘‘Water quality—Evaluation of the ‘ultimate’ anaerobic biodegradability of organic compounds in digested

sludge—Method by measurement of the biogas production’’ (1995 edition).

The third biodegradation test method is the respirometry test. This analytical method determines biodegradation

by measuring the carbon dioxide production and/or oxygen consumption due to microbial oxidation of the test fluid

in sediment. Industry-supplied data using the respirometry test are summarized in Table II.A.2.3.

TABLE II.A.2.3: INDUSTRY RESPIROMETRY BIODEGRADATION TEST RESULTS

Elapsed time of test

Cumulative oxygen consumption over time (mg)

Blank control Rapeseed oil

control

Amodrill 1000

SBF

Day 1 ........................................................................................................................................... 3.38 4.57 4.46

Day 2 ........................................................................................................................................... 6.26 8.26 6.62

Day 3 ........................................................................................................................................... 6.52 9.03 10.49

Day 4 ........................................................................................................................................... 12.68 22.29 14.13

Day 5 ........................................................................................................................................... 16.42 34.29 18.43

Day 6 ........................................................................................................................................... 18.50 41.33 21.02

Day 7 ........................................................................................................................................... 21.40 50.02 24.67

Day 8 ........................................................................................................................................... 24.02 58.42 27.96

Day 9 ........................................................................................................................................... 26.66 66.12 31.19

Day 10 ......................................................................................................................................... 29.10 72.88 34.36

Day 11 ......................................................................................................................................... 31.48 78.86 37.25

Day 12 ......................................................................................................................................... 33.88 84.26 39.96

Day 13 ......................................................................................................................................... 36.27 89.00 42.67

Day 14 ......................................................................................................................................... 38.80 93.33 45.48

Day 15 ......................................................................................................................................... 41.28 97.26 48.24

Day 16 ......................................................................................................................................... 43.31 100.76 50.96

Day 17 ......................................................................................................................................... 45.19 103.86 53.47

21552 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

TABLE II.A.2.3: INDUSTRY RESPIROMETRY BIODEGRADATION TEST RESULTS—Continued

Elapsed time of test

Cumulative oxygen consumption over time (mg)

Blank control Rapeseed oil

control

Amodrill 1000

SBF

Day 19 ......................................................................................................................................... 49.29 110.34 58.86

Day 20 ......................................................................................................................................... 50.80 112.69 60.76

Day 21 ......................................................................................................................................... 52.53 115.34 62.78

Day 22 ......................................................................................................................................... 54.23 117.98 64.83

Day 23 ......................................................................................................................................... 55.73 120.38 66.57

Day 26 ......................................................................................................................................... 60.94 127.73 72.97

Day 27 ......................................................................................................................................... 62.32 129.64 74.76

Day 28 ......................................................................................................................................... 64.00 131.77 76.66

Day 29 ......................................................................................................................................... 65.60 133.81 78.81

Day 30 ......................................................................................................................................... 67.14 135.75 81.04

Day 31 ......................................................................................................................................... 68.59 137.53 82.97

Day 32 ......................................................................................................................................... 70.10 139.32 84.96

Day 33 ......................................................................................................................................... 71.66 141.13 86.98

Day 34 ......................................................................................................................................... 73.09 143.45 88.84

Day 35 ......................................................................................................................................... 74.82 144.51 91.08

Day 36 ......................................................................................................................................... 76.29 146.15 93.17

Day 37 ......................................................................................................................................... 77.47 147.59 94.68

Day 38 ......................................................................................................................................... 79.11 149.22 96.82

Day 39 ......................................................................................................................................... 80.64 150.80 98.87

Day 40 ......................................................................................................................................... 82.31 152.51 101.26

Day 41 ......................................................................................................................................... 83.44 153.83 102.68

Note: data were not collected on Days 18, 24, and 25.

Method Reference: Modification of OPPTS 835.3110: ‘‘Fate, Transport and Transformation Test Guidelines: Ready Biodegradability,’’ EPA

712–C–98–076, January 1998.

A more complete review of these

procedures and data can be found in

section III.B.(b) of the rulemaking

record.

Finally, one commenter on the

February 1999 proposal, American

Petroleum Institute/National Ocean

Industries Association (API/NOIA),

stated, without any supporting data, that

esters biodegrade more quickly than the

alternative non-aqueous fluid systems.

EPA agrees with this statement based on

recent EPA biodegradation test results

(see section II.B.2).

3. Formation Oil Contamination

(Offshore and On-shore Tests)

In the February 1999 proposal, EPA

proposed the BAT limitation and NSPS

for formation oil as zero discharge. EPA

also proposed a screening method

[Reverse Phase Extraction (RPE) method

given in Appendix 6 to Subpart A of

Part 435] and an assurance method [Gas

Chromatograph/Mass Spectrometer (GC/

MS) method given in Appendix 5 to

Subpart A of Part 435] for determining

compliance. These methods continue to

be EPA’s preferred option for the final

rule.

Industry has sponsored research

regarding both of these analytical

methods for determining formation oil

contamination. The RPE procedure is to

be used offshore. It measures ultraviolet

(UV) fluorescence to detect the presence

of aromatic compounds. Since proposal,

refinements have been made in the test

to minimize interference from

emulsifiers. A more complete review of

this procedure can be found in section

III.B.(b) of the rulemaking record.

The GC/MS method is expected to be

performed in a land-based laboratory.

This procedure, which measures the

area under GC peaks and target

aromatics, is a dependable laboratory

technique proposed by EPA to

supplement the RPE test for verification

purposes. A more complete review of

this procedure can be found in section

III.B.(b) of the rulemaking record.

4. SBF on Cuttings Retention Data

In this section, EPA summarizes the

relationship of the industry supplied

data to EPA’s proposal, the relationship

of these data to reductions in discharges

to the environment, and the SBF on

cuttings data submitted by industry.

a. SBF on Cuttings Data in Relation to

EPA’s Proposal. In February 1999, EPA

proposed a BAT limitation and NSPS

for base fluid retained on cuttings as a

maximum value of 10.2 percent, not to

be exceeded by the weighted average for

retention over the course of drilling a

well. EPA also proposed a method for

demonstrating compliance with this

discharge limitation (Appendix 7 to

Subpart A of Part 435). In today’s notice

EPA, with input from industry, presents

the proposed option along with several

alternatives utilizing Best Management

Practices (BMPs). EPA is considering

three options for the final rule for the

BAT limitation and NSPS controlling

SBF retained on discharged cuttings: (1)

a single numeric discharge limitation

with an accompanying compliance test

method; (2) allowing operators to

choose either a single numeric discharge

limitation with an accompanying

compliance test method, or as an

alternative, a set of BMPs that employs

limited cuttings monitoring; or (3)

allowing operators to choose either a

single numeric discharge limitation

with an accompanying compliance test

method or an alternative set of BMPs

that employ no cuttings monitoring.

Further EPA corrected technical

errors in the proposed rule based on the

statistical analysis of the SBF on

cuttings data obtained from the Gulf of

Mexico (GOM). The average percent

SBF on cuttings was corrected from 11.5

to 11.4 for current practice and from

7.11 to 7.09 for the BAT/NSPS

technology. The proposed well averaged

maximum limitation and standard were

corrected from 10.2 to 9.42. Cost and

loading calculations presented in the

February 1999 SBF technical support

documents were not affected by these

changes because these calculations were

based on the rounded values of 11 for

current practice and 7 for the BAT/

NSPS technology. The technical errors

requiring these changes were related to

EPA’s calculation of drilling intervals.

EPA calculates drilling intervals as

the depth drilled since the last

measurement for retention on cuttings.

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21553

EPA uses this measurement in

conjunction with pipe diameter to

estimate the volume of cuttings

associated with a particular retention on

cuttings measurement. EPA then uses

this volume in the weighted summary

statistics for the retention on cuttings

data. Some data used at proposal were

submitted with drilling intervals already

calculated and other data were

submitted with depth measurements

calculated from the ocean floor. In the

proposed rule as published in the

Federal Register, EPA used both sets of

measurements as if they all represented

drilling intervals. However, in the

record for the proposed rule, EPA

calculated and used drilling intervals

for those data submitted with depth

measurements calculated from the

ocean floor. More information on these

errors and the corrections is given in

section I.C(d)(59) of the rulemaking

record.

Several comments received on the

February 1999 proposal related to the

use of cuttings retention data from the

North Sea to set the GOM numeric

guidelines and standards for percent

retention. As discussed below, EPA has

subsequently obtained sufficient data

from the GOM to set limitations and

standards without use of the North Sea

data.

b. Relationship of SBF on Cuttings

Retention Data to Protection of the

Environment. Cuttings retention data

measure the amount of residual drilling

fluid retained on cuttings. A higher

cuttings retention value indicates that

more drilling fluid is adhering to the

cuttings. EPA is interested in the

cuttings retention measurement not only

as an indicator of the amount drilling

fluid discharged into the ocean but also

as an indicator of the ability of cuttings

to biodegrade and disperse and not form

deleterious cuttings piles and mats.

Moreover, understanding the fate and

transport of discharged cuttings is an

important step in modeling and

monitoring potential environmental and

human health impacts.

SBFs are a subcategory of nonaqueous drilling fluids (NAFs) which do

not easily disperse in the water column.

The effects of NAF-cuttings on benthic

fauna may be categorized as being

caused by: (1) physical smothering; (2)

the presence of potential toxic and

hazardous pollutants and

biodegradation by-products (e.g., heavy

metals, aromatics, hydrocarbons,

sulfides); and (3) the organic enrichment

of sediment which may produce anoxic

conditions (Limia and Peresich, 1992).

Field studies indicate that the responses

shown by benthic communities to

cuttings discharges are the result of a

combination of these effects. Numerous

field studies show that the most harmful

benthic effects are generally within 500

meters of development drilling

operations and within 250 meters of

single well sites (Davies et al., 1989).

Reducing the amount of initial base

fluid on cuttings is beneficial in

promoting biodegradation of SBFs in the

benthic environment. Literature data

make clear that the biodegradation of

SBFs in the environment is not simply

an exponential decay (Getliff et al.,

1997). The half-life of the base fluid

decreases as the initial concentration of

base fluid on cuttings decreases.

Therefore, it is vital to minimize the

initial concentration of base fluid on

cuttings discharged to maximize the

rates of biodegradation and seabed

recovery.

Reducing the amount of initial base

fluid on cuttings is also beneficial in

preventing the build-up of deleterious

cuttings piles and mats. A decrease in

benthic individuals within the zone of

maximum cuttings deposition (i.e.,

cuttings piles and mats) is a result of

physical smothering and organic

enrichment which produces anoxic

conditions and toxic sulfide

biodegradation by-products (Daan et al.,

1996; Limia, 1996). A reduction of

benthic individuals beyond the

immediate area of physical impact may

be indicative of a toxic effect (Davies

and Kingston, 1992). The build-up of

these harmful cuttings piles and mats is

controlled by several factors including

the conditions of the receiving waters

(e.g., currents, distance from discharge

to seabed) and the retention of SBF on

cuttings. A study of cuttings piles in the

North Sea found that piles of cuttings

are found predominantly at particular

sites in the central and northern North

Sea, where water depths are greater, and

currents less than, the southern North

Sea (Bell et al., 1998).

Results from laboratory experiments

modeling typical ocean conditions show

that high NAF content on cuttings (i.e.,

high cuttings retention values) lead to

‘‘lumps’’ of material, rather than

separate particles, which rapidly settle

out (i.e., have high fall velocities) to the

benthic environment (Delvigne, 1996).

Moreover, field results show that

cuttings are dispersed during transit to

the seabed and no cuttings piles are

formed when SBF concentrations on

cuttings are held below 5% (Getliff et

al., 1997; Hanni et al., 1998).

Additionally, cuttings discharged from

cuttings dryers (with SBF retention

values under 5%) in combination with

a sea water flush, hydrate very quickly

and disperse like water-based cuttings

(Hanni et al., 1998).

Overall, lowering the percentage of

residual drilling fluid retained on

cuttings increases the recovery rate of

the seabed receiving the cuttings (Getliff

et al., 1997; Vik et al., 1996). Therefore,

limiting the amount of NAF content in

discharged cuttings controls: (1) The

amount of NAF discharged to the ocean;

(2) the biodegradation rate of discharged

NAF; and (3) the potential for NAFcuttings to develop cuttings piles and

mats which are detrimental to the

benthic environment.

c. SBF on Cuttings Data Submitted by

Industry. Subsequent to proposal, SBF

on cuttings data from various formations

within the GOM have been submitted by

an industry workgroup, individual

operators, and by equipment vendors.

These data characterize performance for

a variety of cuttings treatment

technologies, including existing shaker

technologies and add-on equipment.

Several comments on the February 1999

proposal also provided cursory

information and data related to the

performance of new and existing solids

control equipment and drilling fluids.

For example, one comment by Derrick

Equipment Company described SBF

cuttings retention values in the range of

8 to 9% by weight for a GOM well using

a new shale shaker design. A comment

by Baroid Drilling Fluids stated that the

lower viscosity of its new ester-based

drilling fluid will lead to greater

recovery of its ester-based fluid from

cuttings.

Based on these data and other GOM

data presented at proposal, EPA has

modeled and analyzed the cuttings

retention performance of several

technologies. A summary of the revised

models is presented in section III.D. A

summary of the analyses developed by

EPA, including the development of

numeric guidelines and standards, is

presented in section IV.D. Detailed

descriptions of the statistical methods,

summary statistics, overall averages,

and percentiles associated with each

technology can be found in section

III.C.(a) of the rulemaking record.

5. Industry Seabed Survey

Permits authorizing the discharge of

SBF-cuttings are required to meet (a)

technology-based requirements, and (b)

CWA section 403(c) Ocean Discharge

Criteria, or, in State waters of Cook

Inlet, Alaska, State water quality

criteria. The February 1999 proposal

described the CWA 403(c) requirements

and the seabed surveys EPA thinks

would be occurring, based on

information available at that time to

satisfy these permit requirements.

Today’s notice updates the description

21554 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

of the seabed survey efforts that

industry is currently planning.

EPA understands that the industry is

planning a cooperative effort to address

the CWA section 403(c) requirements in

the GOM. Industry representatives have

told EPA that their cooperative seafloor

study would include a review of

historical data on SBF usage on the shelf

and slope, and these data would be

analyzed to select a representative series

of platforms.

The overall objective of the study is

to assess the fate and effects (physical,

chemical, and biological) of discharged

SBF-cuttings at continental shelf (40 m

to 300 m water depth) and deepwater

(>300 m water depth) GOM sites.

Specific sub-objectives include

determining the thickness and areal

extent of cuttings accumulations,

determining the temporal behavior of

SBF concentrations in sediments,

documenting the physical-chemical

sediment conditions, and determining

whether a zone of biological effect

exists.

The study will include four cruises: a

scouting cruise, a screening cruise, and

two sampling cruises. The purpose of

the scouting cruise, which is intended

to take place in late spring of 2000, is

to conduct a preliminary physical

survey of ten continental shelf sites to:

(1) assess the extent of cuttings

accumulations; (2) assess the suitability

of each site for further sampling; and (3)

guide further sampling operations. The

results of this cruise will be used to

select five continental shelf sites where

the subsequent screening cruise will be

conducted.

During the screening cruise, five

continental shelf sites and three

deepwater sites will be surveyed. The

purpose of this cruise is to: (1) Assess

SBF concentrations and other sediment

physical-chemical conditions (e.g.,

oxidation-reduction profile, grain size,

mineralogy, metals, total organic

carbon) at all eight sites; (2) test and

refine the proposed field and laboratory

methods; and (3) make preliminary

benthic infaunal and sediment toxicity

assessments at the five continental shelf

sites. Based on data acquired during this

cruise, sampling strata will be

designated and platform sites will be

designated as primary or secondary. The

three deepwater sites and three of the

five continental shelf sites will be

primary sites, and the remaining two

continental shelf platforms will be

secondary sites.

The sampling cruise will be similar to

the screening cruise in terms of

physical-chemical analyses, but will

include an increased number of

samples. Infaunal and sediment toxicity

analyses will be included at the three

primary continental shelf sites.

Sampling at the two secondary

continental shelf sites will be similar to

that at the primary sites, but the suite of

analyses will not be as extensive (e.g.,

it will not include metals, infaunal, or

sediment toxicity analyses).

EPA plans on using the data from the

first survey to identify any negative

environmental effects from SBF

discharges. If this data becomes

available in time, EPA might use that

information in its assessment of a

controlled discharge option as

compared to the NWQIs of a zero

discharge option. The current work plan

for the seabed survey can be found in

section III.F.(a) of the rulemaking

record.

6. Bioaccumulation

Several comments related to

bioaccumulation were submitted to EPA

in response to the February 1999

proposal. In particular, one industry

commenter stated, without supporting

data, that there is currently sufficient

data available amongst the various

companies to show that synthetic base

fluids are not believed to

bioaccumulate; further, that most

members of the industry groups

maintain operations in the European

sector where bioaccumulation testing of

base fluids has already been conducted

in compliance with the Harmonized

Offshore Chemical Notification Format

(HOCNF) requirements. However,

another commenter stated, also without

supporting data, that marine organisms

higher in the food chain are at

significant risk due to bioaccumulation

of SBF. EPA is again requesting any data

related to the potential of SBF to

bioaccumulate and the related chronic

or toxic effects on higher level

organisms.

7. Technical Performance of Ester-based

Drilling Fluids

In the proposed rule, EPA proposed

its sediment toxicity and biodegradation

BAT limitations and NSPS based on

product substitution with C16–C18

Internal Olefins. Several commenters on

the February 1999 proposal and other

industry stakeholders offered data

related to the technical and

environmental performance of SBFs

(e.g., Limia and Peresich, 1992).

Specifically, three commenters provided

data on the dynamic or kinematic

viscosity of several SBFs (e.g.,

isomerized olefins, esters). Baroid

Drilling Fluids provided data on its

‘‘new ester’’ with a dynamic viscosity

comparable to a C16–C18 IO. This

drilling fluid manufacturer claims that

the new ester allows formulation of

fluids which have cold water

performance comparable to, if not better

than, some IOs (e.g., C16–C18 IO).

Moreover, Baroid Drilling Fluids noted

that the price of esters-based drilling

fluids in the GOM have been reduced in

half since their introduction and use in

the GOM. EPA has also received

information that indicates that esters

still remain 40–90% more expensive

than IOs (Johnston, 2000a). EPA has also

received information that original and

new ester technology continues to

exhibit higher viscosity that could result

in higher downhole losses of whole

drilling fluids and higher cutting

retention values (Friedheim and Conn,

1996; Johnston, 2000a). Finally, EPA has

received information on the technical

limitations (e.g., stability, elastomer

swelling, sediment toxicity, lack of field

experience) of original and new esters

(Daan et al., 1996; Johnston, 2000a;

Patel, 1998; Schaanning et al., 1996).

Due to the potential for better

environmental performance of esterbased drilling fluids, EPA is considering

basing the sediment toxicity and

biodegradation stock limitations and

standards on original esters instead of

the proposed C16–C18 IO. EPA is also

considering sub-categorizing the

regulation, based on the use of esters.

The different sub-categorization options

under consideration by EPA include: (1)

limiting SBF discharges by setting

numeric limitations and standards

based on ester-based drilling fluids

when water temperatures are above the

practical limitations of esters; and (2)

limiting SBF discharges by setting

numeric limitations and standards

based on C16–C18 IOs, thus allowing the

discharge of SBFs other than ester-based

drilling fluids, when water temperatures

are below the practical limitations of

esters.

EPA solicits comment on this

subcategory approach, and again is

requesting any information and data

related to the cost, technical

performance, potential environmental

impacts (e.g., sediment and aquatic

toxicity, biodegradation), and frequency

of industry use of ester-based drilling

fluids.

8. Subsea Pumping Systems

In the February 1999 proposal (64 FR

5495), EPA outlined an innovative

technology, generally referred to as

‘‘subsea pumping,’’ that may potentially

outperform conventional drilling

techniques in very deepwater

conditions (generally greater than 3,000

feet of water). Subsea pumping is

claimed by the developer to contribute

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21555

to a number of environmental,

technical, and economic benefits.

The technology involves pumping the

drilling fluid up a separate riser by

means of pumps at or near the seafloor.

Rotary drilling methods in a system

using subsea pumping are generally

similar to conventional drilling

methods, with the exception that the

drilling fluid and small cuttings (i.e., <

one-quarter inch) are boosted by one or

more pumps near the seafloor. By

boosting the drilling fluid, the adverse

effects on the wellbore caused by the

drilling fluid pressure from the seafloor

to the surface are eliminated, thereby

allowing wells to be drilled with as

much as 50 percent reduction in the

number of casing strings generally

required to line the well wall. Wells are

drilled in less time, including less

trouble time.

The developer of this technology

claims that subsea pumping can

significantly improve drilling

efficiencies and thereby reduce the

volume of drilling fluid discharged, as

well as reduce the non-water quality

effects of fuel use and air emissions.

Because fewer casing strings are needed,

the hole diameter in the upper sections

of the well can be smaller, which

reduces the amount of cuttings

produced. Also, the well bore will

require fewer casing strings of smaller

diameter, resulting in a reduction in

steel consumption. An additional

benefit of subsea pumping systems is

the potential to extend the use of esterbased fluids in the cooler, deeper waters

of the GOM. Finally, subsea system

drilling may double or triple the reach

of horizontal or directional deepwater

delineation sidetrack wells.

Accordingly, this may reduce the

number of delineation wells needed to

characterize a oil and gas formation.

To enable the pumping of drilling

fluids and cuttings to the surface, about

half of the drill cuttings, comprising the

cuttings larger than approximately onequarter inch, are separated from the

drilling fluid and discharged at the

seafloor since these cuttings cannot

reliably be pumped to the surface. With

a currently reported design, the drill

cuttings that are separated at the

seafloor are discharged through an

eductor hose at the seafloor within a

150-foot radius of the well site. The

drilling fluid, which is boosted at the

seafloor and transports the remainder of

the drill cuttings back to the surface, is

conventionally processed.

Since the February 1999 proposal, the

subsea pumping system developer has

reviewed the technology with staff from

Minerals Management Service (MMS)

GOM Office, EPA Region 6, and EPA

Headquarters. In a letter dated May 24,

1999, MMS provided conditional

approval to the developer for using its

subsea system for exploratory and

development wells in Outer Continental

Shelf (OCS) waters. In a letter dated July

30, 1999, EPA Region 6 concluded that

discharges from the developers subsea

system are generally authorized by the

general permit for the western GOM

(Permit No. GMG290000) provided that

the subsea discharges are monitored.

EPA Headquarters staff met with the

developers of the subsea pumping

system on January 18, 2000, to discuss

the technical and environmental

performance of the new technology. As

part of the meeting, the technology

developers submitted a technical basis

for supporting their improved

environmental, technical, and economic

performance. The developers also

discussed with EPA Headquarters staff

their current plans to field test their

subsea pump system solids removal

equipment offshore under atmospheric,

not subsea, conditions. The tests are

scheduled to begin in May 2000 with

data becoming available in July 2000.

The developers are planning to collect

SBF retention data as well as other data

to determine the fractions and

concentrations of SBF discharged

subsea. Notes from the January 18, 2000,

meeting (including the technology

developer technical report), anticipated

subsea pumping field test plans, and the

two previously mentioned letters are

given in section III.B.(b) of the

rulemaking record.

The subsea system developer

commented on the February 1999

proposal and suggested that a definition

for ‘‘subsea pumping’’ and a

clarification of subsea pumping

discharge sampling and monitoring

requirements be added to this notice. In

the supporting documentation for the

proposed rule, Development Document

for Proposed Effluent Limitations

Guidelines and Standards for SyntheticBased Drilling Fluids and other NonAqueous Drilling Fluids in the Oil and

Gas Extraction Point Source Category

(EPA–821–B–98–021), EPA stated that

for purposes of monitoring, samples of

the subsea discharge can be transported

to the surface for analysis.

Based on the potential for reducing

discharges to the environment and as

previously stated in the SBF

Development Document, EPA is

considering different technology options

for this subsea discharge. These options

include limiting the type of drilling

fluids available for use in subsea

pumping systems; different monitoring

and sampling requirements for subsea

discharges; subsea cuttings discharge

dispersal techniques; and cuttings

retention requirements that are different

from surface discharges. EPA is

requesting comments on the most

appropriate limitations and combination

of limitations for these subsea

discharges. EPA is also requesting more

information about the anticipated

percentage of future deepwater drilling

operations that will employ subsea

pumping systems.

9. Cuttings Micro-encapsulation

Systems

EPA Headquarters staff met with the

developers of a new cuttings

management system, silica microencapsulation, on September 23, 1999,

to discuss the technical and

environmental performance of the new

technology. Silica micro-encapsulation

is a process by which the NAF attached

to the cuttings is physically

encapsulated in an insoluble matrix of

amorphous silicate. More information

on this technology is given in section

III.B.(b) of the rulemaking record.

The technology developer claims that

the encapsulated oils do not leach and

do not biodegrade. The stated benefit of

the micro-encapsulation process is the

ability to convert non-aqueous fluid

cuttings into water wet particles.

Consequently, the non-aqueous fluid

cuttings behave in the water column

similarly to water-based fluid cuttings.

The developer claims that this allows

for maximum dispersion of non-aqueous

fluid cuttings. Finally, the developer

claims that the dispersion of the

cuttings into a much greater area

substantially reduces the potential for

benthic smothering and other toxic and

chronic environmental effects.

One issue related to this technology is

the incompatibility of the microencapsulation technology with the

February 1999 proposal method for

determining the amount of drilling fluid

that adheres to drill cuttings. This

method, Appendix 7 to Subpart A of

Part 435–API Recommended Practice

13B–2 (64 FR 5547), is designed to

measure the relative weights of liquid

and solid components in a sample of

wet drill cuttings. The method uses a

known weight of wet cuttings that is

heated in a retort chamber to vaporize

the liquids contained in the sample. The

high heat of the retort analysis

(approximately 930 °F) can break down

the micro-encapsulation coating and

release the previously sequestered oil

droplet. Therefore EPA’s proposed

requirements for minimizing oil on

cuttings and use of the retort method

may eliminate the incentive to use the

micro-encapsulation technology.

21556 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

EPA may consider different

technology options for these microencapsulated cuttings discharges. These

options include product substitution of

only certain types of drilling fluids

available for use in micro-encapsulating

systems; different monitoring and

sampling requirements for microencapsulated discharges; different

toxicity tests; and different cuttings

retention requirements. Specifically,

EPA is proposing that this technology

may be more beneficial in combination

with other technologies (e.g., product

substitution, add-on solids removal

equipment) to assist operators in

meeting site specific CWA section 403

NPDES permit requirements. As stated

previously, switching to less toxic and

more biodegradable drilling fluids,

reducing the oil on cuttings, and

increasing the dispersion of the cuttings

is instrumental in preventing build-up

of cuttings piles and reducing impacts

to the benthic environment. Use of this

micro-encapsulation technology to

promote cuttings dispersion and further

sequester the oil on cuttings, after use of

new solids control equipment, may

provide addition environmental

protection. EPA is requesting comments

and information related to the

environmental, technical, and economic

performance of this and similar microencapsulation technologies and the

incentive/disincentive issue with

respect to the proposed retention

limitation and standard using the retort

method as the compliance test method.

B. EPA Data Collection Since Proposal

Publication

1. Sediment Toxicity Test Results

Because of the limited data available

for the proposal on the sediment

toxicity of both the base fluids and

whole drilling fluid systems, EPA has

begun a study using sediment toxicity

test methods to: (1) determine the

toxicity of various base fluids and whole

synthetic fluid drilling systems on

amphipods for purposes of selecting

fluids that represent the appropriate

level of technology; and (2) evaluate

possible sediment toxicity compliance

method options. The initial tests

conducted in December 1999 at the EPA

Gulf Breeze Laboratory evaluated the

sediment toxicity of three synthetic base

fluids compared to diesel and have

consisted of 96-hour and 10-day

exposure tests with an IO, a LAO, and

an ester as the base fluids as compared

to No. 2 diesel oil. At the same time,

EPA’s contract laboratory, Battelle, also

conducted initial sediment toxicity tests

on mineral oil and paraffin in addition

to the same three synthetic base fluids

evaluated by the EPA Gulf Breeze

Laboratory.

EPA is currently conducting tests to

determine influences of whole fluid

compositions and crude oil

contamination on the sediment toxicity

of an internal olefin (IO), linear alpha

olefin (LAO), and ester. Current and

previous sediment toxicity tests

conducted by EPA have used the ASTM

E1367–92 sediment toxicity method

supplemented with a sediment

preparation procedure (see 64 FR 5536:

Appendix 3 to Subpart A of Part 435).

Table II.B.1.1 summarizes the sediment

toxicity data that EPA has collected

since proposal.

TABLE II.B.1.1: EPA-COLLECTED LC50 SEDIMENT TOXICITY DATA WITH VARIOUS DRILLING BASE FLUIDS FOR TWO

DIFFERENT TIME PERIODS

Drilling base fluid LC50 (mg/Kg) 95% Confidence

interval

EPA Gulf Breeze Laboratory—Generated Data

96-Hour Test ............................................................... Internal Olefin ............................................................. ND NA

Linear Alpha Olefin ..................................................... 750 677–930

Ester ........................................................................... 10812 9138–12793

Diesel .......................................................................... 463 426–505

10-Day Test ................................................................ Internal Olefin ............................................................. 660 423–1029

Linear Alpha Olefin ..................................................... 419 350–502

Ester ........................................................................... ND NA

Diesel .......................................................................... 199 171–232

EPA Contract Laboratory (Battelle)—Generated Data

96-Hour Test ............................................................... Internal Olefin ............................................................. >8000 NA

Linear Alpha Olefin ..................................................... 2921 2260—3775

Ester ........................................................................... 7686 7158—8253

Mineral Oil .................................................................. 436 485—391

Paraffin ....................................................................... 2263 1936—2644

10-Day Test ................................................................ Internal Olefin ............................................................. 2530 2225—2876

Linear Alpha Olefin ..................................................... 1208 1089—1339

Ester ........................................................................... 4275 3921—4662

Mineral Oil .................................................................. 176 163—190

Paraffin ....................................................................... 1151 1038—1276

Method Reference: EPA February 1999 Proposal (64 FR 5488).

ND—Not determined; NA—Not applicable.

In addition, EPA is assessing the

toxicity potential for degradation byproducts. EPA has some information

related to SBF by-products (Candler et

al., 1995; Getliff et al., 1997; Johnston,

2000a). These data show that aerobic

and anaerobic degradation mechanisms

for many SBFs (especially linear

hydrocarbons) produce by-products that

include biodegradable alcohols and fatty

acids. Some SBFs, such as linear

paraffins, are still the subject of some

debate as to their exact mode of

biodegradation and associated byproducts under anaerobic conditions. In

addition, ester-based drilling fluids byproducts (e.g., alcohols) may exhibit

toxic effects in the water column

(Johnston, 2000a). EPA solicits

comments and data on whether there

are any known persistent or toxic byproducts created by the biodegradation

of synthetic base fluids. This

information will allow EPA to assess the

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21557

overall environmental impact of using

synthetic base fluids.

Finally, as originally stated in the

February 1999 proposal (64 FR 5491),

EPA may require additional or

alternative controls as part of the BAT/

NSPS discharge options based on

method development and data gathering

subsequent to today’s notice: (1)

Maximum sediment toxicity of drilling

fluid at point of discharge (minimum

LC50, mL drilling fluid/kg dry sediment

by 10-day sediment toxicity test or

amended test); (2) maximum aqueous

phase toxicity of drilling fluid at point

of discharge (minimum LC50 by

Suspended Particulate Phase (SPP) test

(see Appendix 2 of Subpart A of Part

435) or amended SPP test); and (3)

maximum potential for bioaccumulation

of stock base fluid (maximum

concentration in sediment-eating

organisms). In particular, EPA is

interested in controlling the toxicity of

SBFs in the sediment and the water

column and may require both a

sediment toxicity test and an aqueous

phase toxicity test to assess overall

toxicity.

A more complete review of the

sediment toxicity procedures and data

can be found in section III.B.(a) of the

rulemaking record.

2. Biodegradation Test Results

Because of the limited data available

for the proposal on the biodegradation

of SBFs, EPA has begun a study using

the solid phase biodegradation test,

proposed in February 1999, to: (1)

determine the biodegradation of various

synthetic base fluids for purposes of

selecting fluids that represent the

appropriate level of technology; and (2)

evaluate possible biodegradation

compliance options. This project began

in January 2000 and results are

anticipated to be finalized in March

2000. Table II.B.2.1 summarizes the data

collected to date. A more complete

review of these procedures and data can

be found in section III.B.(a) of the

rulemaking record.

TABLE II.B.2.1: EPA SOLID PHASE BIODEGRADATION TEST

Percent loss relative to day 0

Ester

(percent)

Paraffin

(percent)

Poly (alpha)

olefin

(percent)

Mineral oil

(percent)

Internal

olefin

(percent)

Linear alpha

olefin

(percent)

Day 0 ................................................................................ 0 0 0 0 0 0

Day 14 .............................................................................. 53 21 22 20 9 8

Day 28 .............................................................................. 60 19 25 21 18 16

Method Reference: EPA February 1999 Proposal (64 FR 5488).

3. EPA Engineering Data Collection

Activities

During the week of October 25, 1999,

EPA staff traveled to Texas and

Louisiana to observe onshore and

offshore equipment used for treating

and disposing of SBF and SBF-cuttings.

Highlights of the onshore portion of the

field trip include visits to an operating

cuttings dryer unit, a fracture slurry

injection facility, and a barge facility on

the GOM intercoastal waterway.

Offshore highlights included visits to

two oil and gas drilling operations to

observe waste management and

pollution prevention practices. EPA

staff also observed working solids

control equipment including cuttings

dryers. These cuttings dryers are

designed to recover more SBF from

cuttings generated by primary and

secondary shale shakers. This field trip

also included an all day meeting with

cuttings dryer equipment vendor

representatives and members of

industry. Field notes from the site visit

and minutes of the all day meeting can

be found in section III.B.(a) of the

rulemaking record.

EPA also obtained information from

the industry primarily related to the perwell aspects of drilling with SBF in

three subject areas: (1) Drilling

operations; (2) solids control equipment

and systems; and (3) costs, in order to

better understand current and emerging

SBF and SBF-waste management

practices.

Finally, EPA collected information

from MMS regarding accidental spills of

OBFs and SBFs. Spills can release small

and large quantities of drilling fluid. In

particular, undetected leaking lines can

release several hundred barrels of

drilling fluid while accidental riser

disconnects can release several

thousand barrels of whole drilling fluid

into the environment. Specifically, EPA

is interested in: (1) the occurrences of

accidents and events that can cause the

release of OBF and SBF whole drilling

fluid (e.g., riser disconnects, blow-outs,

shallow water flow problems); (2) the

number of these accidents and events

over the past five years for each MMS

region (Alaska, California, GOM); (3) the

location of these events (i.e., shallow or

deepwater); and (4) the volumes

associated with these accidents and

events. Preliminary information is that

there have been several spills of OBFs

over the past five years, but most were

small volumes. In addition, MMS data

identifies three events, including two

riser disconnects, that resulted in

significant releases of SBFs into the

environment for the months of January

and February 2000. Under the zero

discharge option EPA assumes that all

operators requiring NAF will switch to

OBFs. As the toxicity of OBFs is greater

than SBFs, EPA will use this spill data

as a factor in supporting the selection of

a controlled discharge option in the

final rule.

A more complete review of the EPA

collected engineering data can be found

in section III.B.(a) of the rulemaking

record.

4. Non-Water Quality Environmental

Impacts (NWQI)

The additional cuttings retention data

submitted to EPA (see section II.A.4)

were used in the revision of the

engineering models that form the basis

for all per-well numeric compliance

analyses. Based on changes in the

engineering models described below in

section III.A, EPA revised the numeric

NWQIs of fuel usage, air emissions, and

solid waste generation.

The U.S. Department of Energy (DOE)

collected information about currently

operating onshore commercial disposal

facilities that are permitted to receive

offshore drilling wastes. The Argonne

National Laboratory (DOE) contacted

State officials in Louisiana, Texas,

California, and Alaska to obtain this

information. EPA also identified a list of

Louisiana commercial non-hazardous

oilfield wastes (NOW) facilities from the

Louisiana Department of Natural

Resources.

EPA also contacted Alaska, Texas,

and Louisiana regulatory agencies to

obtain current information concerning

21558 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

management of offshore and coastal

exploration and production wastes. The

Texas Natural Resource Conservation

Commission (TNRCC) provided permit

information and waste disposal

limitations for the Texas fracture slurry

injection facility visited by EPA staff

(see section II.B.3). The Alaska Oil and

Gas Conservation Commission (AOGCC)

provided information related to Cook

Inlet formation disposal of drilling

fluids and cuttings.

EPA also reviewed two papers that

detail operations of a large Louisiana

onshore fracture slurry injection facility

operated by Chevron for Naturally

Occurring Radioactive Materials/NonHazardous Oilfield Wastes (NORM/

NOW) (Baker et al., 1999a; Baker et al.,

1999b). Currently, this Chevron facility

is limited by its permit to only handle

exploration and production wastes from

Chevron GOM operations.

EPA also contacted Cook Inlet,

Alaska, operators to identify the current

and projected use of SBF and the most

current waste management options for

drill cuttings and fluids. Operators

noted that few wells were being drilled

with SBF due to NPDES general permit

prohibition of SBF discharges.

Furthermore, Cook Inlet operators noted

that the only drill cuttings and fluid

management options available to them

are land disposal of cuttings or grinding

and injection of the cuttings back into

the formation. Land disposal of OBFand SBF-cuttings was identified as cost

prohibitive.

In considering all options for

management of non-aqueous fluids

(NAF) and NAF-cuttings, EPA is also

identifying possible scenarios for crossmedia contamination. In particular, EPA

is trying to identify former NOW

treatment, storage, or disposal facilities

that are now CERCLA (or ‘‘Superfund’’),

RCRA Corrective Action, or State lead

cleanup sites. An initial search by EPA

identified several such sites including

several sites around Abbeville,

Louisiana. Accordingly, EPA is

requesting additional information

related to other sites (Superfund, RCRA

Corrective Action, or State lead) that

have been contaminated with NOW

from offshore operations.

The findings of current onshore waste

management options and former NOW

facilities that are now cleanup sites

outlined in this section are presented in

section III.B.(a) of the rulemaking

record.

Also subsequent to the proposal, EPA

has monetized the human health

benefits associated with volatile organic

compound (VOC), particulate matter

(PM), and sulfur dioxide (SO2) emission

reductions for the two controlled

discharge options. The valuation

methodology is presented in section III.

The results of these revisions are

presented in section IV below.

5. Economic Data (including Deep Water

Model Wells)

EPA collected information from

industry regarding model deepwater

project costs for the Gulf of Mexico,

produced water treatment costs,

wellhead oil and gas prices, and drilling

activity forecasts. A summary of the

data is provided in section III.G of the

rulemaking record.

EPA is developing a methodology to

examine the economic and financial

impacts of the SBF guidelines on both

existing and new deepwater oil and gas

projects in response to comments from

industry that these projects are vastly

different from the projects analyzed as

part of the Offshore Oil and Gas Effluent

Guidelines economic analysis. At

proposal, EPA relied on the results of

that latter analysis showing Gulf of

Mexico projects to be only minimally

affected by even the most stringent

drilling waste option (the zero discharge

option). Because of the unique nature of

deepwater projects and because of their

greater distance from shore, industry

believes deepwater projects need to be

evaluated for economic impacts

resulting from options considered for

the rule.

EPA is thus developing a computer

model similar to the one used for the

Offshore rule, and also nearly identical

to the one developed for the Main Pass

operations in the Gulf of Mexico

investigated during the Coastal Oil and

Gas Effluent Guidelines rule. The

general structure of the model is based

on the Main Pass Model with a few

minor variations [for example,

severance tax is not an issue, so this line

item is not used (see Economic Impact

Analysis of Final Effluent Limitations

Guidelines and Standards for the

Coastal Subcategory of the Oil and Gas

Extraction Point Source Category,

Appendices A and B, EPA–821–R–96–

022)].

The major differences of this model

compared to the Main Pass model are

the inputs. EPA investigated a number

of deepwater projects for use as model

projects. These projects included all

currently operating projects, as well as

a number that should come on line

shortly. Over 30 projects fit this

description. From these initial projects,

EPA selected as many as possible to use

in modeling deepwater projects. Data

availability was the primary criterion

used in selecting the model projects.

EPA selected all deepwater projects for

analysis that operated in 1998 and that

had original proved reserves data

available in public documents. The

most recent publicly available

documents on proved reserves are those

provided by MMS on its website and

these documents are current through

December 31, 1996. Proved reserves are

used to distinguish the relative size of

projects, since the indication of the

ultimate size of a project is reserves, not

necessarily the current production (new

projects that have not completed the

maximum number of wells that would

be productive at any one time would

end up classified as smaller than they

will eventually become). Size of project

is important, since results will be

reported over a group of projects (i.e,

results for small, medium, and large

projects) rather than project-by-project.

Size of reserves also allows EPA to

determine how many wells might be

drilled at a project over time.

Using the data availability criterion,

EPA reduced the number of projects that

can be modeled to twenty. One project

did not operate in 1998, and the others

either have not yet started producing, or

are so new that original proved reserves

had not been calculated for them in

December 1996. The twenty projects

include four small projects (original

proved reserves of 10 million barrels of

oil equivalent (BOE) or less, eight

medium-size projects (original proved

reserves approximately between 10

million and 100 million BOE), and eight

large projects (original proved reserves

over 100 million BOE). BOE for each

project is the sum of the oil (42 gal. oil

= 1 BOE) and natural gas (1,000 scf =

0.178 BOE). To model new projects,

however, five of the twenty projects

were dropped from the analysis as being

too old or as using construction

technologies unlikely to be used in the

future. The remaining 15 projects

generally had been producing less than

5 years in 1998.

Other information was obtained either

from industry contacts or was based on

data developed by EPA and used either

in analyzing the economic impacts of

the Offshore or Coastal Subcategory Oil

and Gas Effluent Guidelines. Section

III.G of the rulemaking record provides

data on projects used to model

deepwater projects as well as

assumptions and sources of data for the

oil and gas financial model.

6. Environmental Assessment Data

a. Water and Sediment Quality

Criteria. Subsequent to conducting

water quality analyses for the

Environmental Assessment (EA) for the

proposed rule, EPA published its

revised recommended water quality

criteria for arsenic (deletion of human

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21559

health criterion); copper (increased from

2.4 μg/l to 4.8 μg/l and 3.1 μg/l for acute

and chronic aquatic community criteria,

respectively); mercury (increased from

0.025 μg/l to 0.94 μg/l for chronic

aquatic community criterion), and

phenol (deletion of human health

criterion) in the Federal Register

(December 10, 1998; 63 FR 68354). In

addition Alaska promulgated new State

water quality standards for toxic

pollutants on May 27, 1999 (see Alaska

Administrative Code, Title 18, Chapter

70 or section III.F.(a).2 of the

rulemaking record). These deletions and

corrections are incorporated in revisions

to the analyses of water column, pore

water, and sediment guidelines quality

outlined in the February 1999

Environmental Assessment Document

(EPA–821–B–98–019).

b. Dilution Data. The same model

used in the February 1999 proposal,

Brandsma (1996), was used in this

notice to estimate the concentration of

synthetic fluids within the water

column for assessment of attainment

with recommended water quality

criteria. These revised dilution

calculations are used for the water

column water quality analyses and for

the calculations of exposure

concentrations for the health benefits

analyses.

c. Review of the Seabed Surveys. In

response to comments and new data

received, EPA revised the Seabed

Survey portion of the Environmental

Assessment. All of the studies presented

in the original EA were re-analyzed to

correct omissions and errors identified

by commenters. One additional study

was submitted by a commenter, BP

Amoco, entitled Deepwater Sampling at

a Synthetic Drilling Mud Discharge Site

on the Outer Continental Shelf,

Northern Gulf of Mexico (Fechhelm et

al., 1999). EPA reviewed this study

which investigated the deepwater

benthic effects of a SBF (90% linearalpha olefins and 10% esters) discharge

and added relevant data to the EPA EA

analyses.

EPA EA models use a mean of SBF

sediment concentrations from various

seabed surveys found in the literature.

EPA updated the mean SBF sediment

concentration (at 100m from the

modeled discharge) from 13,892 mg/kg

to 14,741 mg/kg to incorporate new data

identified in the BP Amoco benthic

study.

d. Receipt of the United Kingdom

Offshore Operators Association

(UKOOA) Research Reports. In June

1998, UKOOA, supported by the Oil

Industry International Exploration and

Production Forum (E & P Forum) and in

co-operation with the Norwegian oil

association (OLF), launched an

initiative to tackle the historical legacy

of accumulated drill cuttings beneath

offshore installations in the North Sea.

Many of these North Sea cuttings piles

were generated from the practice of

discharging cuttings from multiple wells

into a single deposition point. These

drilling operations also used OBFs

which contain a high PAH content. The

ultimate goal of the UKOOA research is

to identify the best environmental

practice and the best techniques

available for managing these

accumulations.

Immediately prior to publication of

this notice, EPA acquired several reports

related to the UKOOA industry research

activities in the North Sea. These

UKOOA reports are based on literature

review and field studies. Specifically,

EPA received UKOOA reports related to

cuttings pile toxicity, faunal

colonization of cuttings piles,

contaminant leaching from drill cuttings

piles, and natural degradation and

estimated recovery time-scale.

EPA plans to incorporate the relevant

major findings and conclusions into the

final EPA SBF Environmental

Assessment document and analyses.

Specifically, EPA plans on using

relevant North Sea data in assessing its

method alternatives for determining

sediment toxicity, biodegradation, and

bioaccumulation. Moreover, EPA plans

to incorporate relevant data from North

Sea field studies into assessing the

various discharge and zero discharge

options for SBF-wastes. Section III.B.(a)

of the rulemaking record gives summary

of the data collected to support the EPA

SBF Environmental Assessment.

III. Revised Models

A. Revised Engineering Models

1. Large Volume Discharges

Through discussions with

stakeholders and the October 1999 site

visits to offshore drilling operations,

EPA has obtained more information

about current and emerging solids

control practices. Regarding current

practices, EPA has re-evaluated its

model of the ‘‘standard’’ or ‘‘baseline’’

solids control system. The baseline

model presented in the February 1999

proposal consisted of a primary shale

shaker that discharges cuttings and a

secondary shale shaker that discharges

fine-particle cuttings (referred to as

‘‘fines’’).

Since proposal, EPA learned that

cuttings are discharged from both

primary and secondary shale shakers,

and that fines are generated from

additional equipment such as highspeed shale shakers (called ‘‘mud

cleaners’’) and centrifuges whose

purpose is to treat the drilling fluid by

removing undesirable fine solids. These

fines were reported by one industry

commenter on the February 1999

proposal to have SBF cuttings retention

values as high as 20 percent by weight.

Therefore, the revised baseline model

consists of primary and secondary shale

shakers, plus a ‘‘fines removal unit’’ that

may be either a mud cleaner or a

centrifuge. Discharges from the baseline

model system consist of cuttings from

the primary shale shaker, cuttings from

the secondary shale shaker, and fines

from the fines removal unit. Based on

data provided in the spreadsheets

submitted by industry representatives,

the baseline model volume fractions of

the three discharges, expressed as

percentages of the total volume of all

cuttings discharged from the baseline

model well, are 78.5% for the primary

shakers, 18.5% for the secondary

shakers, and 3% for the fines removal

unit.

EPA received sufficient additional

cuttings retention data from GOM

sources to re-evaluate the discharges of

these three units and to calculate a

revised baseline long-term average

retention value of 11.4% by weight of

SBF on cuttings. Despite the revision of

the retention data and the model

baseline system, the revised long-term

average retention value is only slightly

higher than the 11% originally

calculated for the proposal, providing

further confidence in the accuracy of the

baseline model and associated data.

Since the February 1999 proposal, the

GOM offshore drilling industry has

increased its use of ‘‘add-on’’ cuttings

drying equipment, ‘‘cuttings dryers,’’ to

reduce the amount of SBF adhering to

the cuttings prior to discharge.

Specifically, over twenty GOM SBF well

projects utilized these cuttings dryers in

the recent past to reduce the amount of

SBF discharged (Johnston, 2000a).

Current data available to EPA indicates

that these cuttings dryers can operate

consistently and efficiently when

properly installed and maintained.

Specifically, vendor supplied data

associated with these cuttings dryer

deployments suggest that the overall

cuttings dryer downtime (i.e., time

when cuttings dryer equipment is not

operable) is approximately one percent

of the overall operating time (Johnston,

2000a).

At the time of the February 1999

proposal, EPA had obtained retention

data from only one such add-on

technology, namely the Mud-10

vibrating centrifugal dryer. Since then,

EPA has observed the operation of

another drying technology, generally

21560 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

referred to as a vertical centrifuge dryer.

The vertical centrifuge dryer unit serves

the same purpose and occupies the

same location in the treatment train as

the Mud-10 unit. EPA generically refers

to the Mud-10 unit and the vertical

centrifuge dryer as the ‘‘cuttings dryer.’’

Immediately prior to publication of

this notice, EPA also received limited

cuttings retention data from a third type

of add-on equipment referred to as a

‘‘squeeze press’’ mud recovery unit.

When installed, the squeeze press mud

recovery unit occupies the same

location as the above-mentioned

cuttings dryers and serves to reduce the

amount of SBF adhering to the cuttings

prior to discharge. The specific data for

the squeeze press were received too late

to include in the statistical

determination of retention values for

today’s notice. However, these data are

included in the public record for the

rule and EPA solicits comments on

them (Johnston, 2000b). These data,

along with additional retention data

received from other industry sources,

will be evaluated and included in the

appropriate engineering and statistical

analyses used to support the cuttings

retention limitation in the final rule.

Most cuttings dryer applications

include a centrifuge or mud cleaner in

the treatment train, to serve the same

purpose as the fines removal unit in the

baseline system (i.e., to remove

undesirable fine solids from the drilling

fluid recovered by the cuttings dryer).

Therefore, EPA’s revised model of BAT/

NSPS-level solids control includes

primary and secondary shale shakers

that send all their cuttings to a cuttings

dryer, followed by a fines removal unit.

There are two discharges from the BAT/

NSPS-level model solids control system:

one from the cuttings dryer and one

from the fines removal unit. The BAT/

NSPS-model volume fractions of the

two discharges, expressed as

percentages of the total volume of all

cuttings discharged from the BAT/

NSPS-model well, are 97% for the

cuttings dryer and 3% from the fines

removal unit. EPA, however, solicits

more volume fraction data to further

refine its baseline and BAT/NSPS

discharge models.

For today’s notice, EPA evaluated two

different scenarios based on the above

BAT/NSPS-model solids control system.

The first scenario assumes that both the

cuttings from the cuttings dryer and the

fines from the fines removal unit are

discharged. This first BAT/NSPS-model

scenario is essentially unchanged from

the BAT/NSPS-model presented at the

February 1999 proposal. The long-term

average SBF cuttings retention value for

this first BAT/NSPS-model scenario is

2.68% by weight. This new long-term

average cuttings retention value is lower

than the February 1999 proposal BAT/

NSPS-model long-term average cuttings

retention value of 7% by weight. The

difference is attributable to the

replacement of the North Sea data with

data from recent GOM drilling projects.

The second BAT/NSPS-model scenario

assumes that only the cuttings are

discharged, and the fines, which

represent a comparably smaller volume

of waste, are retained for zero discharge

via hauling to shore for land-based

disposal. Therefore, the long-term

average cuttings retention value for this

second BAT/NSPS-model scenario is

equal to the retention value for the

cuttings dryer, 2.45% by weight.

At this time, EPA thinks that data

from the GOM are adequate to represent

field conditions throughout the United

States. These data include variations in

geological formations, drilling

conditions, and rates of penetration.

However, EPA is still requesting

cuttings retention data from offshore

and coastal drilling operations that use

SBFs. In particular, EPA is requesting

SBF cuttings retention data from United

States offshore or coastal oil and gas

exploration and production facilities

operating outside of the GOM. If EPA

does not receive additional non-GOM

data, EPA is comfortable with applying

the GOM data to other offshore and

coastal regions in the United States.

The analyses for compliance costs,

pollutant loadings, and numeric nonwater quality environmental impacts are

based on the volumes of waste solids

and adhering drilling fluid estimated to

be discharged from each of four model

wells. The model wells are defined in

terms of four categories: deep water (i.e.,

≥1000 ft) development, deep water

exploratory, shallow water (i.e., <1000

ft) development and shallow water

exploratory. While the model well sizes

are unchanged, the volumes of adhering

drilling fluid were revised based on the

revised retention values. Based on

further communication since the

February 1999 proposal with industry

about current and future drilling plans

in the GOM, California, Alaska, and

North Carolina, the numbers of each

type of model well drilled annually are

also unchanged. EPA is, however,

requesting more data detailing the

annual number of shallow water and

deep water SBF-wells. EPA is also

requesting data on the conditions and

frequency when SBFs are chosen over

water-based drilling fluids, when both

drilling fluids are technically acceptable

for drilling (i.e., some shallow water

wells).

EPA also re-evaluated the zerodischarge option using the updated

baseline retention data. The only

notable change in the approach to the

zero-discharge analysis is the

distribution of wells using land-based

disposal versus wells using onsite

injection. The original analysis assumed

that 80% of the affected wells would

use land-based disposal and 20% would

use onsite injection. While this

assumption remains applicable to

shallow water wells, EPA learned from

industry sources that onsite injection is

currently less applicable to deep water

wells, due to limitations of mechanical

equipment, geology, and well

placement. Therefore, the zero discharge

analysis now assumes that all deep

water wells will haul cuttings to shore

for land-based disposal. As zero

discharge remains a proposed

management option, EPA is requesting

additional data and information related

to what drilling fluids and waste

management practices operators will

likely use and the overall impact on the

annual number of drilling projects if

EPA selects the zero discharge

management option for SBFs.

The current engineering cost analysis

also assigns the installation and

downtime costs to every well. However,

EPA recognizes that it is likely that

multiple wells would be drilled from a

single installation, thereby reducing the

effect of the installation cost on each

well’s total compliance cost. It is also

likely that some drilling rigs will

purchase and permanently install

cuttings dryers and fines removal units,

further reducing the effect of installation

costs on any one well. The data EPA has

gathered to date are limited in this

regard. Therefore, EPA requests

additional information pertaining to the

average number of wells drilled

annually with SBF per platform, and the

number of platforms capable of

permanently installing cuttings dryers

and fines removal units.

Details of the revised engineering

models are provided in a technical

support document in section III.C.(b) of

the rulemaking record.

2. Small Volume Discharges

In its study of current solids control

practices, EPA learned that SBF is

controlled with zero discharge practices

at the drill floor, in the form of vacuums

and sumps to retrieve spilled fluid. EPA

also learned that approximately 75

barrels of solids coated with SBF can

accumulate in the dead spaces of the

mud pit, sand trap, and other equipment

in the drilling fluid circulation system.

Current practice is to either wash these

solids out with water for overboard

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21561

discharge, or to retain the waste solids

for disposal.

Since zero discharge practices at the

drill floor during drilling are the current

practice, no additional costs were

considered for controlling spills of SBF

at this location. However, EPA did

investigate options for controlling the

discharges of accumulated solids

generated by equipment cleaning

procedures at the end of a drilling

project. Assuming that every drilling

project generates approximately 75

barrels of these small-volume waste

accumulated solids, the costs vary only

by: (1) geographic region; and (2) the

numbers of wells in each regulatory

scenario. EPA used the line-item costs

developed for the zero discharge

compliance cost analysis to calculate

per-well and total costs for existing and

new sources to dispose of accumulated

solids via hauling to land based disposal

facilities. The industry-wide costs

resulting from this analysis are given

below in section IV, Table IV.A.2.1.

B. Revised Economic Models

EPA plans to use the same

methodologies in analyzing firm-level

impacts used at proposal, but will

update information to include at a

minimum 1998 financial data as well as

1997 financial data. The year 1998 was

not a good year for the oil and gas

industry, whereas 1997 was a good year,

so these two years should provide some

sense of the volatility of the industry.

EPA still expects that the impact on

firms will be minimal, even given the

difficult year the industry had in 1998.

Additionally, EPA will use the same

methodology for the small business

analysis that was used at proposal. EPA

does not expect the analysis to change

significantly from proposal because: (1)

Costs have not changed substantially;

(2) only a few small operators are

believed to be using SBFs; and (3) very

few wells are drilled by small operators

in a year.

Instead of relying on the Offshore Oil

and Gas Effluent Guidelines EIA to

provide a sense of financial impact at

the facility level, however, EPA is

changing the approach to allow

deepwater projects to be modeled

financially, as discussed in section II.

At the time of this notice, EPA

believes that economic impacts from

even the most stringent option (i.e., zero

discharge of SBFs) will have only

minimal influence on most deepwater

projects. However, as zero discharge

remains a proposed management option,

EPA is requesting additional data and

information related to whether or not

the selection of the zero discharge

management option for SBFs will affect

the overall annual number of drilling

projects in deep and shallow waters in

the United States. Further technical

details are presented in supporting

documentation in section III.G of the

rulemaking record, which discusses

potential impacts on typical, or average,

deepwater projects.

However, because averages can

obscure the effects at the most

vulnerable projects, EPA will be looking

closely at the potential for option costs

to cause any measurable impacts at

projects that do not conform to the

parameters of the average project using

the financial model. Although model

outputs will be reported in the aggregate

by project size, each individual project

will be represented in the model inputs

to allow EPA to identify impacts more

precisely.

The projects likeliest to show some

potential for impact are the smallest

projects (both existing and new, if the

existing projects continue to drill), the

oldest existing projects (such as Lena

and Cognac, which have produced over

80 percent of their original proved

reserves as of 1996), or very marginal

projects. Because any project could be

marginal when all the factors are

accounted for, even the relatively small

cost of the SBF rule could have an

impact on one or more projects,

although, at this time, EPA believes this

possibility is small.

C. Revised Environmental Assessment

(EA) Models

Revisions to the regulatory options

such as the revised retention on cuttings

values and the addition of another

controlled discharge option has resulted

in changes in the SBF environmental

assessment. The retention on cuttings

affects both the pollutant loadings and

the volume of waste discharged, thereby

affecting the water quality, sediment

quality and human health impacts. EPA

has therefore re-iterated the various EA

analyses and the results are presented in

section IV below. There are, however,

no changes in the EA models as

outlined in the February 1999 proposal

and the Environmental Assessment

Document (EPA–821–B–98–019).

The models developed to calculate

the NWQIs of air emissions, fuel usage,

and solid waste generation have been

revised parallel to the revisions in the

engineering models described in section

III.A. The revised waste volumes that

resulted from new retention data

required adjustments of such NWQI

model elements as numbers of boat

trips, cuttings boxes, and crane lifts. An

additional NWQI model was developed

for the BAT/NSPS discharge scenario

based on 2.45% retention on cuttings.

For both of the discharge scenarios, the

energy requirements for the cuttings

dryer and fines removal units were

revised to reflect the newer technologies

now accounted for in the engineering

models. Finally, the zero discharge

model was changed according to the

new finding that deep water wells

cannot readily utilize onsite injection

and, rather, haul cuttings to shore-based

disposal facilities.

Also subsequent to the February 1999

proposal, EPA monetized the human

health benefits for the two controlled

discharge options associated with

reducing volatile organic compound

(VOC), particulate matter (PM), and

sulfur dioxide (SO2) emissions. The

valuation methodology used to conduct

the monetized benefits analysis is

presented in Environmental Assessment

of the Final Effluent Limitations

Guidelines and Standards for the

Pharmaceutical Manufacturing Industry

(EPA–821–B–98–008). The results of

these revisions are presented in section

IV below.

D. Revised Models for the Performance

of Cuttings Treatment Technologies

As stated in the February 1999

proposal, EPA is considering setting

limitations and standards for the

percent retention of synthetic-based

drilling fluids on cuttings that may be

discharged from the cuttings dryer and

fines removal technologies. EPA

received cuttings retention data after the

February 1999 proposal (see section

II.A.4). This section of the notice

outlines the revisions made to the

statistical models for the performance of

cuttings treatment technologies. A

summary of the output of these revised

models with new data is given in

section IV.D.

EPA analyzed cuttings treatment data

presented at proposal using well

averages where each cuttings retention

value is weighted by an associated hole

volume. Since publication of the

proposed statistical support document

in February 1999, EPA incorporated

four changes into the statistical methods

used to estimate summary statistics

which support the development of

numeric limitations and standards for

the retention of synthetic-based drilling

fluids on cuttings. These changes are:

(1) Imputation of volume-weighted

factors for zero and negative drilling

intervals; (2) correction to the estimator

for volume-weighted variances; (3) the

addition of uniformly-weighted

summary statistics; and (4)

consideration of the 99th percentile

rather than the 95th percentile for the

development of numeric limitations and

standards for the maximum well

21562 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

averaged percent retention of SBF on

cuttings.

EPA generally estimated the volume

of cuttings using the drilling interval

and the pipe diameter immediately

preceding a retention measurement.

However, at times, the drilling intervals

are reported as zero or negative. A

negative drilling interval indicates that

the drill pipe has been pulled up to

facilitate drilling in a new direction.

EPA excluded negative interval data

from the proposal. In this report,

negative drilling intervals are treated in

the same fashion as zero drilling

intervals.

At proposal, EPA estimated weighted

variances as if the weights could only

take on a small number of possible

values. However, those weights are

based on the volume of cuttings

associated with a particular drilling

interval and that volume may take on

infinitely many values. In this report,

EPA estimated weighted variances as if

the weights could only take on infinitely

many values.

Under the assumption that the

retention on cuttings increased with the

depth drilled, EPA proposed numeric

guidelines and standards using

retention values weighted by the

volume drilled. However, the graphics

showing percent retention versus depth

drilled do not indicate that this is true

(EPA, 2000). Therefore, EPA has added

the use of uniformly-weighted summary

statistics as part of EPA’s statistical

models. With no apparent relationship

between depth drilled and percent

retention, the uniformly-weighted

summary statistics are more

appropriate. Basing numeric guidelines

and standards on a single type of

measurement, as opposed to a

combination of multiple types of

measurements, will reduce the

measurement variability associated with

the guidelines and standards.

Additional benefits of setting numeric

guidelines and standards based on

uniformly-weighted summary statistics

include eliminating the need to: (1)

Calculate the length of interval drilled;

(2) impute volumes where zero or

negative intervals exist; and (3) use

unusual variance estimation procedures.

EPA prefers to set numeric guidelines

and standards for percent retention

based on uniformly-weighted summary

statistics as opposed to volume

weighted summary statistics.

EPA proposed numeric limitations

and standards under the assumption

that, on a long-term average basis, good

engineering practice would allow

appropriately designed and well

operated solids control equipment

systems to perform at least as well as

approximately 95% of the systems

whose data were used to develop the

limitations and standards.

Operationally, cuttings retention values

are averaged over the course of drilling

an individual well and EPA’s candidate

BAT limitation or NSPS is the estimated

95th percentile for the available well

averages.

The CWA confers considerable

discretion in determining what

constitutes best available technology

and best available demonstrated

technology. In exercising this discretion,

the Agency has proposed and

promulgated limitations and standards

that provide for the variability observed

in application of these technologies.

This allowance provides for variation in

the performance of the recommended

treatment technologies and establishes a

standard that EPA expects well operated

treatment systems to be capable of

achieving at all times.

Given that there is less experience to

date with the application of the cuttings

dryer technology than many other

candidate BAT and NSPS technologies

generally, the Agency is also

considering setting numeric limitations

and standards based on the 99th

percentile. This would provide a larger

allowance for treatment variability than

is provided by the proposed limitations

and standards based on the 95th

percentile.

Detailed descriptions of the statistical

methods, summary statistics, overall

averages, and percentiles associated

with each technology can be found in

section III.C.(a) of the rulemaking

record.

IV. Revised Analyses

A. Revised Compliance Costs Results

1. Large Volume Discharges

Based on the revised engineering

models described in section III.A above,

EPA revised its calculations of baseline,

compliance option, and incremental

compliance costs. The industry profile

and the methodology for estimating

costs that were presented with the

proposed rule have not changed for

today’s notice. The results of the revised

compliance cost analyses are presented

in Table IV.A.1.1 for existing sources

and in Table IV.A.1.2 for new sources.

TABLE IV.A.1.1: SUMMARY ANNUAL COST/SAVINGS, EXISTING SOURCES (1998$/YEAR)

Technology basis

Costs (savings) in 1998$/year

[wells/year]

Gulf of

Mexico

[wells/yr]

Offshore

California

[wells/yr]

Cook Inlet,

Alaska

[wells/yr]

Total

[wells/yr]

Baseline/Current Practice Technology Costs:

Discharge with 11.4% retention of SBF on cuttings .......... 20,032,850 ..........

[94 wells/yr] .........

NAa ..................... NAa ..................... 20,032,850

[94 wells/yr]

Zero Discharge via land disposal or onsite injection (current OBF-drilled wells only).3,494,062 ............

[23 wells/yr] .........

2,287,281 ............

[12 wells/yr] .........

214,237 ...............

[1 well/yr] .............

5,995,580

[36 wells/yr]

Total Baseline Costs per Area ................................... 23,526,912 ..........

[117 wells/yr] .......

2,287,281 ............

[12 wells/yr] .........

214,237 ...............

[1 well/yr] .............

26,028,430

[130 wells/yr]

Technology Option Costs:

Discharge with 2.68% retention of SBF on cuttings .......... 20,257,350 ..........

[117 wells/yr] .......

2,463,440 ............

[12 wells/yr] .........

211,350 ...............

[1 well/yr] .............

22,932,140

[130 wells/yr]

Discharge with 2.45% retention of SBF on cuttings .......... 20,365,837 ..........

[117 wells/yr] .......

2,472,517 ............

[12 wells/yr] .........

214,672 ...............

[1 well/yr] .............

23,053,026

[130 wells/yr]

Zero Discharge of SBF-wastes via land disposal or onsite injection.31,666,153b .........

[94 wells/yr] .........

NAa ..................... NAa ..................... 31,666,153

[94 wells/yr]

Incremental Tech. Option Costs (Savings):

Discharge with 2.68% retention of SBF on cuttings .......... (3,269,562) ..........

[117 wells/yr] .......

176,159 ...............

[12 wells/yr] .........

(2,887) .................

[1 well/yr] .............

(3,096,290)

[130 wells/yr]

Discharge with 2.45% retention of SBF on cuttings .......... (3,161,075) ..........

[117 wells/yr] .......

185,236 ...............

[12 wells/yr] .........

435 ......................

[1 well/yr] .............

(2,975,404)

[130 wells/yr]

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21563

TABLE IV.A.1.1: SUMMARY ANNUAL COST/SAVINGS, EXISTING SOURCES (1998$/YEAR)—Continued

Technology basis

Costs (savings) in 1998$/year

[wells/year]

Gulf of

Mexico

[wells/yr]

Offshore

California

[wells/yr]

Cook Inlet,

Alaska

[wells/yr]

Total

[wells/yr]

Zero Discharge of SBF-wastes via land disposal or onsite injection.11,633,303c .........

[94 wells/yr] .........

NAa ..................... NAa ..................... 11,633,303

[94 wells/yr]

a NA: Not applicable since currently there are no discharges of SBF-cuttings in these waters.

bThis technology option cost estimates zero discharge costs associated with the 94 GOM wells that are currently allowed to discharge SBF. cThis incremental technology option cost only covers the 94 GOM wells that are currently allowed to discharge SBF and does not include

baseline compliance costs of zero discharge for the 23 GOM OBF wells (i.e., $3,494,062).

TABLE IV.A.1.2: SUMMARY ANNUAL COST/SAVINGS, NEW SOURCES (1998$/YEAR)

Technology basis Gulf of Mexico

Baseline/Current Practice Technology Costs:

Discharge with 11.4% retention of SBF on cuttings ................................................................................................................ 2,306,325

Technology Option Costs:

Discharge with 2.68% retention of SBF on cuttings ................................................................................................................ 1,388,250

Discharge with 2.45% retention of SBF on cuttings ................................................................................................................ 1,395,913

Zero Discharge of SBF-wastes via land disposal or onsite injection ...................................................................................... 4,581,838

Incremental Technology Option Costs (Savings):

Discharge with 2.68% retention of SBF on cuttings ................................................................................................................ (918,075)

Discharge with 2.45% retention of SBF on cuttings ................................................................................................................ (910,412)

Zero Discharge of SBF-wastes via land disposal or onsite injection ...................................................................................... 2,275,513

Note: All cost estimates in this table are based on an assumption of 19 new source wells per year.

Details of the revised compliance cost data and analyses are available in a technical support document in section

III.C.(b) of the rulemaking record.

2. Small Volume Discharges

As stated in section III.A.2 of this notice, EPA learned that SBF is controlled with zero discharge practices at

the drill floor, in the form of vacuums and sumps to retrieve spilled fluid. Industry estimated that essentially all

of the SBF that spills on the rig floor is recovered using the controls described above. The amount of SBF spilled

on the rig floor that is not captured by current practices is estimated at less than 1 gallon SBF per 100 feet drilled.

Industry representatives have stated that industry is split on the practice of discharging accumulated solids with

some discharging accumulated solids provided permit limitations and standards are met and others opting to haul

this material to shore for disposal (see section II.B.3). Approximately 75 barrels per well of fine solids and barite,

of which up to 25% is SBF, accumulate in the rig mud pits, sand traps, and other equipment. Several hundred barrels

(approximately 200 to 400 barrels) of water are used to wash out the mud pits. Industry representatives also indicated

to EPA that those oil and gas extraction operations that discharge wash water and accumulated solids first recover

free SBF.

EPA used the line-item costs developed for the zero discharge compliance cost analysis to calculate per-well and

total costs for existing and new sources to dispose of accumulated solids via hauling to land based disposal facilities.

Section III.A.2 outlines the assumptions used to calculate the annual zero discharge costs for small volume wastes

given below in Table IV.A.2.1. Overall, the estimated per-well costs (1998$) were $1,221 for GOM wells, $2,186 for

Offshore California wells, and $10,638 for Cook Inlet wells.

TABLE IV.A.2.1: ANNUAL ZERO DISCHARGE COSTS FOR SMALL-VOLUME SBF WASTES (1998$/YEAR)

Technology Basis Gulf of Mexico California Cook Inlet, AK Total

Existing Sources:

Baseline and BAT/NSPS Discharge Scenarios a ..................................... $142,857 $26,235 $10,638 $179,730

Zero Discharge b ....................................................................................... 114,774 d NA d NA 114,774

New Sources:

All Scenarios (Baseline, BAT/NSPS Discharge, and Zero Discharge) c .. 23,199 d NA d NA 23,199

a Costs are the same for baseline and two discharge scenarios because each analysis is based on 117 wells.

bZero discharge costs for existing sources are based on 94 wells.

c Costs are the same for all new-source scenarios because each analysis is based on 19 wells.

d NA: Not Applicable.

B. Revised Pollutant Loadings Results

EPA reviewed additional information regarding drilling fluid additives provided by the industry representatives in

response and subsequent to the February 1999 proposal, and found no information prompting changes to the concentrations

or list of pollutants presented at the time of proposal. EPA revised the pollutant loadings analysis according to the

changes in the engineering and statistical models described in section III.A and III.D of this notice.

21564 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

The loadings analysis depends on the estimated volumes of cuttings and SBF discharged per model well for each

discharge scenario. Other than adjusting the loadings to the revised waste volumes and revised discharge scenarios,

the analysis remains unchanged from the February 1999 analyses. Tables IV.B.1 and IV.B.2 present the revised loadings

for existing and new sources, respectively. EPA assumes that operators will switch from OBFs in the current baseline

model to SBFs under both SBF controlled discharge options. These tables present the loadings associated with discharges

of SBF and entrained fines [e.g., <5 microns (10¥6 meters)]. EPA also calculated the loadings associated with SBF

solids that can be removed by solids control equipment (e.g., >5 microns).

TABLE IV.B.1: SUMMARY ANNUAL SBF POLLUTANT LOADINGS FOR EXISTING SOURCES (LBS/YEAR) a

Technology basis

SBF pollutant loadings (reductions) in pounds/year a [wells/year]

Gulf of Mexico Offshore

California Cook Inlet, Alaska Total

Baseline/Current Practice Tech. Loadings:

Discharge with 11.4% retention of SBF on cuttings .......... 34,364,661 ..........

[94 wells/yr] .........

b NA ..................... b NA ..................... 34,364,661

[94 wells/yr]

Zero Discharge via land disposal or onsite injection (current OBF-drilled wells only).0 ..........................

[23 wells/yr] .........

0 ..........................

[12 wells/yr] .........

0 ..........................

[1 well/yr] .............

0

[36 wells/yr]

Total Baseline Loadings per Area .............................. 34,364,661 ..........

[117 wells/yr] .......

0 ..........................

[12 wells/yr] .........

0 ..........................

[1 well/yr] .............

34,364,661

[130 wells/yr]

Technology Option Loadings:

Discharge with 2.68% retention of base fluid on cuttings 7,328,175 ............

[117 wells/yr] .......

466,072 ...............

[12 wells/yr] .........

26,413 .................

[1 well/yr] .............

7,820,660

[130 wells/yr]

Discharge with 2.45% retention of base fluid on cuttings 6,464,827 ............

[117 wells/yr] .......

411,167 ...............

[12 wells/yr] .........

23,302 .................

[1 well/yr] .............

6,889,295

[130 wells/yr]

Zero Discharge of SBF-wastes via land disposal or onsite injection.0 ..........................

[94 wells/yr] .........

b NA ..................... b NA ..................... 0

[94 wells/yr]

Increm. Tech. Opt. Loadings (Reductions):

Discharge with 2.68% retention of base fluid on cuttings (27,036,486) ........

[117 wells/yr] .......

466,072 ...............

[12 wells/yr] .........

26,413 .................

[1 well/yr] .............

(26,544,001)

[130 wells/yr]

Discharge with 2.45% retention of base fluid on cuttings (27,899,834) ........

[117 wells/yr] .......

411,167 ...............

[12 wells/yr] .........

23,302 .................

[1 well/yr] .............

(27,465,365)

[130 wells/yr]

Zero Discharge of SBF-wastes via land disposal or onsite injection.(34,364,661) ........

[94 wells/yr] .........

b NA ..................... b NA ..................... (34,364,661)

[94 wells/yr]

aSBF pollutant loadings only includes loadings associated with discharges of SBF and entrained fines (e.g., < 5 microns)

b NA Not Applicable

TABLE IV.B.2: SUMMARY ANNUAL POLLUTANT LOADINGS FOR NEW SOURCES (LBS/YEAR) a

Technology basis Gulf of Mexico

Baseline/Current Practice Technology Loadings:

Discharge with 11.4% retention of SBF on cuttings ................................................................................................................ 3,949,786

Technology Option Loadings:

Discharge with 2.68% retention of SBF on cuttings ................................................................................................................ 745,855

Discharge with 2.45% retention of SBF on cuttings. ............................................................................................................... 657,981

Zero Discharge of SBF-wastes via land disposal or onsite injection ...................................................................................... 0

Incremental Technology Option Loadings (Reductions):

Discharge with 2.68% retention of SBF on cuttings ................................................................................................................ (3,203,931)

Discharge with 2.45% retention of SBF on cuttings. ............................................................................................................... (3,291,805)

Zero Discharge of SBF-wastes via land disposal or onsite injection ...................................................................................... (3,949,786)

Note: All loading (reduction) estimates in this table are based on an assumption of 19 new source wells/yr.

aOnly includes loadings associated with discharges of SBF and entrained fines (e.g., <5 microns)

The zero discharge option also

reduces the amount of SBF-solids [i.e.,

solids that can be removed by solids

control equipment (e.g., >5 microns)]

from the current baseline. The estimated

annual baseline discharges of SBFsolids from existing sources is

126,321,650 lbs./year. The estimated

annual loadings (in lbs./year) of SBFsolids for existing sources are:

152,240,270 (2.68% retention controlled

discharge option); 147,673,062 (2.45%

retention controlled discharge option);

and 0 (zero discharge option). The

estimated annual baseline discharge of

SBF-solids from new sources is

14,519,050 lbs./year. The estimated

annual loadings (in lbs./year) of SBFsolids for new sources are: 14,519,050

(2.68% retention controlled discharge

option); 14,083,488 (2.45% retention

controlled discharge option); and 0 (zero

discharge option). Complete details of

the loadings analysis are available in a

technical support document in the

rulemaking record for this notice.

C. Revised Non-Water Quality

Environmental Impacts (NWQI) Results

1. Air Emissions and Fuel Usage

EPA revised the analysis of the

numeric NWQIs of air emissions and

fuel usage pursuant to the changes in

the engineering models described in

section III.A of today’s notice. Changes

to the numeric NWQI analysis derive

from the revised waste volumes, as well

as changes in the BAT/NSPS discharge

scenarios.

In both the first and second BAT/

NSPS discharge scenarios, additional air

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21565

emissions and fuel usage result from the

addition of the fines removal unit. Both

scenarios also incorporate the average

energy and fuel requirements of the two

types of cuttings dryer that EPA

observed in October 1999 (see section

II.B.3). In the second BAT/NSPS

discharge scenario in which the fines

waste stream is retained for shipping to

land-based disposal, additional air

emissions and fuel usage are incurred

for a portion of the supply boat trip, and

for trucks and other equipment involved

in the land disposal zero discharge

scenario.

As described in section III.A, EPA

learned from industry representatives

that onsite injection is not generally

technologically practicable for deep

water drilling projects. Therefore,

NWQIs attributable to hauling and land

disposing drilling wastes were assigned

to all deep water wells in the zero

discharge analysis. Tables IV.C.1 and

IV.C.2 present the revised air emissions

(tons/yr) and fuel (BOE/yr) usage for

existing and new sources, respectively.

Other than the specific changes

described above, the methodology for

the numeric NWQI analysis is

unchanged since the February 1999

proposal. Details of this analysis are

available in a technical support

document located in the rulemaking

record for this notice.

TABLE IV.C.1: SUMMARY ANNUAL NON-WATER QUALITY ENVIRONMENTAL IMPACTS, EXISTING SOURCES

Technology basis

Non-water quality environmental impacts reductions (increases)

[wells/year—wpr]

Gulf of Mexico Offshore California Cook Inlet, AK Total

Air

emissions

(tons/yr)

Fuel

usage

(BOE/yr)

Air

emissions

(tons/yr)

Fuel

usage

(BOE/yr)

Air

emissions

(tons/yr)

Fuel

usage

(BOE/yr)

Air

emissions

(tons/yr)

Fuel

usage

(BOE/yr)

Baseline/Current Practice NWQIs:

Discharge with 11.4% retention

of base fluid on cuttings.

42 .............

[94 wpy] ...

4,512 .......

[94 wpy] ...

aNA .......... aNA .......... aNA .......... aNA .......... 42 ............

[94 wpy] ...

4,512

[94 wpy]

Zero Discharge (current OBFwells only).65 ............

[23 wpy] ...

4,811 .......

[23 wpy] ...

47 ............

[12 wpy] ...

2,940 ........

[12 wpy] ...

2.5 ...........

[1 wpy] .....

338 ...........

[1 wpy] .....

115 ...........

[36 wpy] ...

8,089

[36 wpy]

Total Baseline NWQIs per

Area.

107 ...........

[117 wpy]

9,323 .......

[117 wpy]

47 ............

[12 wpy] ...

2,940 .......

[12 wpy] ...

2.5 ...........

[1 wpy] .....

338 ...........

[1 wpy] .....

157 ..........

[130 wpy]

12,601

[36 wpy]

Technology Option NWQIs:

Discharge with 2.68% retention

of SBF on cuttings.

127 ...........

[117 wpy]

10,422 ......

[117 wpy]

7.6 ...........

[12 wpy] ...

673 ...........

[12 wpy] ...

0.06 .........

[1 wpy] .....

40 ............

[1 wpy] .....

135 ...........

[130 wpy]

11,135

[130 wpy]

Discharge with 2.45% retention

of SBF on cuttings.

191 ...........

[117 wpy]

15,685 ......

[117 wpy]

52 ............

[12 wpy] ...

853 ..........

[12 wpy] ...

0.20 .........

[1 wpy] .....

67 ............

[1 wpy] .....

243 ...........

[130 wpy]

16,605

[130 wpy]

Zero Discharge of SBF-wastes

via land disposal or onsite injection.

561 ..........

[94 wpy] ...

39,702 ......

[94 wpy] ...

aNA .......... aNA .......... aNA .......... aNA .......... 561 .......... 39,702

[94 wpy]

Incr. Tech. Opt. NWQI Red. (Incr.):

Discharge with 2.68% retention

of SBF on cuttings.

20 .............

[117 wpy]

(1,099) .....

[117 wpy]

40 .............

[12 wpy] ...

2,267 .......

[12 wpy] ...

2.45 .........

[1 wpy] .....

298 ...........

[1 wpy] .....

22 ............

[130 wpy]

1,466

[130 wpy]

Discharge with 2.45% retention

of SBF on cuttings.

(84) ..........

[117 wpy]

(6,362) .....

[117 wpy]

(4.8) .........

[12 wpy] ...

2,087 .......

[12 wpy] ...

2.31 .........

[1 wpy] .....

271 ...........

[1 wpy] .....

(87) ..........

[130 wpy]

(4,004)

[130 wpy]

Zero Discharge of SBF-wastes

via land disposal or onsite injection.

(519) ........

[94 wpy] ...

(35,191) ...

[94 wpy] ...

aNA .......... aNA .......... aNA .......... aNA .......... (519) ........

[94 wpy] ...

(35,191)

[94 wpy]

Note: 1 ton = 2000 lbs; BOE = barrels of oil equivalent

a NA: Not Applicable

TABLE IV.C.2: SUMMARY ANNUAL NON-WATER QUALITY ENVIRONMENTAL IMPACTS, NEW SOURCES

Technology basis

Gulf of Mexico

Air emissions

(tons/yr)

Fuel usage

(BOE/yr)

Baseline/Current Practice Technology NWQIs:

Discharge with 11.4% retention of SBF on cuttings .................................................................................... 4.8 515

Technology Option NWQIs:

Discharge with 2.68% retention of SBF on cuttings .................................................................................... 13 1,073

Discharge with 2.45% retention of SBF on cuttings. ................................................................................... 23 1,923

Zero Discharge of SBF-wastes via land disposal or onsite injection .......................................................... 68 4,784

Incremental Technology Option NWQIs Reductions (Increases):

Discharge with 2.68% retention of SBF on cuttings .................................................................................... (8.2) (558)

Discharge with 2.45% retention of SBF on cuttings. ................................................................................... (18) (1,408)

Zero Discharge of SBF-wastes via land disposal or onsite injection .......................................................... (63) (4,269)

Note: All NWQI reductions (increases) in this table are based on an assumption of 19 new source wells/yr

Note: 1 ton = 2000 lbs; BOE = barrels of oil equivalent

21566 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

2. Solid Waste Generation and

Management

EPA assumes that based on the

relative cheaper cost of OBF

(approximately 5 times less expensive

per barrel than SBFs), operators will use

OBFs rather than SBFs if EPA selects

the zero discharge option for all SBFwastes. Consequently, operators will be

land disposing or injecting OBFs if EPA

selects the zero discharge option for all

SBF-wastes.

As stated in the February 1999

proposal, the regulatory options

considered for this rule will not cause

generation of additional solids.

However, EPA calculated the amount of

waste cuttings that would be land

disposed and injected onsite in each

regulatory scenario, and determined that

there would be a considerable reduction

in the amount of mineral-oil or diesel

oil-contaminated cuttings land disposed

and injected with the implementation of

either of the controlled discharge

options.

Applying the revised waste volumes

and discharge scenarios described

above, the accounting of disposed waste

is revised as follows. In the baseline

analysis, wells that currently drill using

OBFs generate 27 million (MM) pounds

of waste cuttings that are land disposed,

and 6.8 MM pounds that are injected

onsite, for a total of 34 MM pounds of

waste cuttings disposed. This amount of

disposed waste would be reduced to

zero under the BAT/NSPS options

allowing discharge at 2.68% retention,

and would be reduced to 6.4 MM

pounds under the BAT/NSPS option

allowing discharge at 2.45%. The 6.4

MM pounds disposed in the second

discharge scenario is the fine particle

waste retained for hauling to land based

disposal. Under the zero discharge

option, the baseline amount of waste

disposed is increased to 152 MM

pounds.

3. Safety Issues

The impact of the effluent limitation

guidelines (ELG) on safety is one factor

considered in the non-water quality

environmental impact analysis. EPA has

identified two safety issues related to

drilling fluids: (1) deleterious vapors

generated by organic materials in

drilling fluids; and (2) waste hauling

activities that increase the risk of injury

to workers. EPA is requesting comments

and data related to these two safety

issues as well as other safety issues

related to drilling fluid selection and

waste management.

a. Vapors Generated by Organic

Materials in Drilling Fluids. One of the

key concerns in exploration and

production projects is the exposure of

wellsite personnel to vapors generated

by organic materials in drilling fluids

(Candler et al., 1995). Areas on the

drilling location with the highest

exposure potentials are sites near solids

control and open pits. These areas are

often enclosed in rooms and ventilated

to prevent unhealthy levels of vapors

from accumulating. If the total volume

of organic vapors can be reduced then

any potential health effects will also be

reduced regardless of the nature of the

vapors.

Generally speaking the aromatic

fraction of the vapors is the most toxic

to the mammalian system. The high

volatility and absorbability through the

lungs combined with their high lipid

solubility serve to increase their

toxicity. OBFs have a high aromatic

content and vapors generated from

using these drilling fluids include

aromatics (e.g., alkybenzenes,

naphthalenes, and alkyl-naphthalenes),

alkanes (e.g., C7–C18 straight chained

and branched), and alkenes. Some

minerals oils also generate vapors that

contain the same types of chemical

compounds, but generally at lower

concentrations, as those found in the

diesel vapors (e.g, aromatics, alkanes,

cyclic alkanes, and alkenes). Because

SBF are manufactured from compounds

with specifically defined compositions,

the subsequent compound can exclude

toxic aromatics. Consequently, toxic

aromatics can be excluded from the

vapors generated by using SBFs.

In general, SBFs (e.g., esters, LAOs,

PAOs, IOs) generate much lower

concentrations of vapors than do OBFs

(Candler et al., 1995). Moreover, the

vapors generated by these SBFs are less

toxic than traditional OBFs because they

do not contain aromatics.

b. Waste Hauling Activities. Industry

has commented in previous effluent

guidelines, such as the Coastal

Subcategory Oil and Gas Extraction and

Development ELG, that a zero discharge

requirement would increase the risk of

injury to workers due to increased waste

hauling activities. These activities

include vessel trips to and from the

drilling platform to haul waste, transfer

of waste from the platform onto a

service vessel, and transfer in port onto

a barge or dock.

EPA has identified and reviewed

additional data sources to determine the

likelihood that imposition of a zero

discharge limitation on cuttings

contaminated with SBF could increase

risk of injury due to additional waste

hauling demands. The sources of safety

data are the U.S. Coast Guard (USCG),

the Minerals Management Service

(MMS), the American Petroleum

Institute (API), and the Offshore Marine

Service Association (OMSA). The

following is a summary of the findings

from this review.

The data indicate that there are

reported incidents that are associated

with the collection, hauling, and

onshore disposal of wastes from

offshore. However, the data do not

distinguish whether any of these

incidents can be attributed to specific

waste management activities.

Most offshore incidents are due to

human error or equipment failure. The

rate at which these incidents occur will

not be changed significantly by

increased waste management activities.

However, if the number of man hours

and/or equipment hours are increased,

there will be more reportable incidents

given an unchanged incident rate. These

potential increases may be offset by

reduced incident rates through

increased training or equipment

maintenance and inspection; but these

changes cannot be predicted. One

indication that training and

maintenance can reduce incident rates

is a 1998 API report entitled ‘‘1997

Summary of U.S. Occupational Injuries,

Illnesses, and Fatalities in the Petroleum

Industry,’’ which established that injury

incident rates have been decreasing over

the last 14 years. If this decrease

continues, there should be no increase

in the number of safety incidents due to

a requirement to haul SBF-contaminated

cuttings to shore for disposal. The

details of this analysis are available in

a technical support document in the

rulemaking record for today’s notice.

4. Monetized Health Benefits

EPA estimated emissions associated

with each of the regulatory options as

part of the NWQI analyses. The

pollutants considered in the NWQI

analyses are nitrogen oxides (NOX),

volatile organic carbon (VOC),

particulate matter (PM), sulfur dioxide

(SO2), and carbon monoxide (CO). Of

these pollutants, EPA has monetized the

human health benefits or impacts

associated with VOC, PM, and SO2

emissions using the methodology

presented in the Environmental

Assessment of the Final Effluent

Limitations Guidelines and Standards

for the Pharmaceutical Manufacturing

Industry (EPA–821–B–98–008). Each of

these pollutants have human health

impacts and reducing these emissions

can reduce these impacts.

Several VOCs exhibit carcinogenic

and systemic effects and VOCs, in

general, are precursors to ground-level

ozone, which negatively affects human

health and the environment. PM

impacts include aggravation of

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21567

respiratory and cardiovascular disease

and altered respiratory tract defense

mechanisms. SO2 impacts include nasal

irritation and breathing difficulties in

humans and acid deposition in aquatic

and terrestrial ecosystems.

The unit values (in 1990 dollars) are

$489 to $2,212 per megagram (Mg) of

VOC; $10,823 per Mg of PM; and $3,516

to $4,194 per Mg of SO2. Using the

Engineering News Record Construction

Cost Index (see www.enr.com/cost/

costcci.asp) these conversion factors are

scaled up using the ratio of 5920:4732

(1998$:1990$). EPA currently does not

have unit values for CO and NOX and

is soliciting information regarding their

valuation. Following is a summary of

the monetized benefits for each of the

regulatory options for both existing and

new sources.

TABLE IV.C.3: SUMMARY OF MONETIZED HUMAN HEALTH BENEFITS OR IMPACTS ASSOCIATED WITH VOC, PM, AND SO2

EMISSIONS, EXISTING SOURCES (1998$/YR)

Criteria air pollutant

VOC PM SO2

Baseline/Current Practice Air Emissions, Mg/yr:

Discharge with 11.4% retention of SBF on cuttings ................................................................... 2.15 ............. 1.87 ............. 1.74

Zero Discharge (current OBF wells only) .................................................................................... 9.57 ............. 1.93 ............. 1.68

Total Baseline Air Emissions, Mg/yr ..................................................................................... 11.72 ........... 3.80 ............. 3.42

Compliance Air Emissions, Mg/yr:

(1) Discharge with 2.68% retention of SBF on cuttings .............................................................. 6.90 ............. 5.98 ............. 5.57

(2) Discharge with 2.45% retention of SBF on cuttings .............................................................. 25.68 ........... 9.65 ............. 8.45

(3) Zero Discharge a ..................................................................................................................... 113.84 ......... 20.96 ........... 18.42

Incremental Compliance Emission Reductions (Increases), Mg/yr:

(1) Discharge with 2.68% retention of SBF on cuttings .............................................................. 4.82 ............. (2.18) ........... (2.15)

(2) Discharge with 2.45% retention of SBF on cuttings .............................................................. (13.96) ......... (5.85) ........... (5.03)

(3) Zero Discharge a ..................................................................................................................... (11.69) ......... (19.09) ......... (16.68)

Unit Value of Poll. Reductions, 1990$/Mg: b ....................................................................................... 489 to 2,212 10,823 ......... 3,516 to

4,194

Unit Value of Poll. Reductions, 1998$/Mg: c ....................................................................................... 612 to 2,767 13, 540 ........ 4,399 to

5,247

Incremental Compliance Benefits (Costs), 1998$/yr:

(1) Discharge with 2.68% retention of SBF on cuttings .............................................................. 2,950 to

13,337.

(29,517) ....... (9,458) to

(11,281)

(2) Discharge with 2.45% retention of SBF on cuttings .............................................................. (8,544) to

(38,627).

(79,209) ....... (22,127) to

(26,392)

(3) Zero Discharge a ..................................................................................................................... (68,354) to

(309,046).

(258,479) ..... 73,375) to

(87,520)

aVia land disposal or on-site offshore injection

b Conversion factors from Environmental Assessment of the Final Effluent Limitations Guidelines and Standards for the Pharmaceutical Manufacturing Industry¢ (EPA–821–B–98–008). cScaled from 1990$ using the Engineering News Record Construction Cost Index.

TABLE IV.C.4: SUMMARY OF MONETIZED HUMAN HEALTH BENEFITS OR IMPACTS ASSOCIATED WITH VOC, PM, AND SO2

EMISSIONS, NEW SOURCES (1998$/YR)

Criteria air pollutant

VOC PM SO2

Baseline/Current Industry Practice Air Emissions, Mg/yr:

Discharge with 11.4% retention of SBF on cuttings. .................................................................. 0.25 ............. 0.21 ............. 0.20

Compliance Air Emissions, Mg/yr:

(1) Discharge with 2.68% retention of SBF on cuttings .............................................................. 0.66 ............. 0.57 ............. 0.53

(2) Discharge with 2.45% retention of SBF on cuttings .............................................................. 2.73 ............. 0.91 ............. 0.88

(3) Zero Discharge a ..................................................................................................................... 14.62 ........... 2.67 ............. 2.32

Incremental Compliance Emission Reductions (Increases), Mg/yr:

(1) Discharge with 2.68% retention of SBF on cuttings .............................................................. (0.41) ........... (0.36) ........... (0.33)

(2) Discharge with 2.45% retention of SBF on cuttings .............................................................. (2.48) ........... (0.70) ........... (0.68)

(3) Zero Discharge a ..................................................................................................................... (14.37) ......... (2.45) ........... (2.13)

Unit Value of Poll. Reductions, 1990$/Mg: b ....................................................................................... 489 to 2,212 10,823 ......... 3,516 to

4,194

Unit Value of Poll. Reductions, 1998$/Mg: c ....................................................................................... 612 to 2,767 13,540 ......... 4,399 to

5,247

Incremental Compliance Benefits (Costs), 1998$/yr:

(1) Discharge with 2.68% retention of SBF on cuttings .............................................................. (251) to

(1,134)

(4,874) ......... (1,452) to

(1,731)

(2) Discharge with 2.45% retention of SBF on cuttings .............................................................. (1,518) to

(6,862)

(9,478) ......... (2,991) to

(3,568)

(3) Zero Discharge a ..................................................................................................................... (8,794) to

(39,762)

(33,173) ....... (9,370) to

(11,176)

aVia land disposal or on-site offshore injection.

21568 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

b Conversion factors from Environmental Assessment of the Final Effluent Limitations Guidelines and Standards for the Pharmaceutical Manufacturing Industry (EPA–821–B–98–008). cScaled from 1990$ using the Engineering News Record Construction Cost Index.

D. Revised Cuttings Retention

Limitations and Standards

As stated in the February 1999

proposal, EPA is considering setting

limitations and standards for the

percent retention of synthetic-based

drilling fluids on cuttings that may be

discharged from the cuttings dryer and

fines removal technologies. EPA

received cuttings retention data after the

February 1999 proposal (see section

II.A.4) and revised its statistical models

(see section III.D).

As demonstrated by oil drilling

operations in various geologic

formations within the Gulf of Mexico

(see section II.A.4), the average of the

individual well averages for percent

SBF retention on cuttings from the

cuttings dryer is 2.45, the estimated

95th percentile is 3.11, and the

estimated 99th percentile is 3.38. The

observed individual well averaged SBF

cuttings retention values are all less

than the 95th percentile. For fines

removal equipment, the average of the

individual well averages for percent

SBF retention on cuttings is 10.0, the

estimated 95th percentile is 13.1, and

the estimated 99th percentile is 14.4.

Only one of the observed individual

well SBF cuttings retention values for

fines removal equipment exceeds the

95th percentile and none exceed the

99th percentile.

Based on these summary statistics,

EPA has revised the proposed

limitations and standards for percent

retention of drilling fluids on cuttings.

Assuming that: (a) 97% of the volume

of cuttings discharged come from the

cuttings dryer and 3% from fines

removal; and (b) the limit will be based

on a 95th percentile; the new discharge

limitation of base fluid retained on

cuttings is 3.41% [i.e., (0.97)(3.11%) +

(0.03)(13.1%) = 3.41%]. Assuming that:

(a) 97% of the volume of cuttings

discharged come from the cuttings dryer

and 3% from fines removal; and (b) the

limit will be based on a 99th percentile;

the new discharge limitation of base

fluid retained on cuttings is 3.71% [i.e.,

(0.97)(3.38%) + (0.03)(14.4%) = 3.71%].

EPA is also considering basing

percent retention limitations and

standards on the cuttings dryer alone, in

conjunction with zero discharge for all

other cuttings. In that case, the

discharge limitation of base fluid

retained on cuttings would be 3.11%

when using the 95th percentile or

3.38% when established using the 99th

percentile.

If EPA selects numeric maximum well

averaged cuttings retention discharge

limitations and standards as the only

method for controlling SBF discharges

associated with cuttings in the final

rule, then all operators would be

expected to either: (1) meet the numeric

maximum well averaged cuttings

retention limitations and standards; or

(2) dispose of their waste through onsite formation injection or ship their

cuttings to shore for land disposal. In

addition, EPA may elect in the final rule

to allow operators the flexibility of

choosing either numeric limitations and

standards or BMPs to control SBF

discharges associated with cuttings (see

section V). A detailed description of the

statistical analyses used to develop the

proposed limitations and standards for

percent retention of drilling fluids on

cuttings is given in section III.C.(a) of

the rulemaking record.

E. Revised Environmental Assessment

Results

The complete results of the revised

EA analyses are given in section III.F.(b)

of the rulemaking record.

1. Water Column Water Quality

Analyses

In the February 1999 proposal EA

analyses, there were no exceedances of

water quality criteria in the water

column. Based on the revised EA

analyses using updated dilution values

and Federal water quality criteria, there

are still no water quality criteria

exceedances in the water column for

any of the regulatory options being

considered.

2. Pore Water Quality Analyses

The revised EA analyses estimate that

baseline-model (or BPT) pore water

pollutant concentrations at 100 m from

the discharge exceed water-quality

criteria for: (1) three pollutants (Cr, Pb,

Ni) for the deep water exploratory well;

(2) one pollutant (Cr) for the shallow

exploratory well; and one pollutant (Cr)

for the deepwater development well.

Barite is used as a weighting agent in

the drilling fluid and is also the primary

source of heavy metals (e.g., Cr, Pb, Ni)

in SBF. Therefore, the baseline-model

pore water exceedances are not due to

the synthetic material in the SBF but

rather the SBF weighting agents.

The revised EA analyses estimate that

both BAT/NSPS-model controlled

discharge options result in no pore

water pollutant concentrations that

exceed water-quality criterion.

3. Sediment Guidelines Analyses

In the February 1999 proposal, the

BAT/NSPS-model controlled discharge

option resulted in sediment guidelines

exceedances for the deep water and

shallow water exploratory wells. EPA

proposed sediment guidelines can be

found in section I.D.(a).13 of the

rulemaking record. The revised EA

sediment guidelines analyses, based on

updated water quality criteria, loadings,

and dilution data, result in exceedances

under the baseline model (or BPT)

scenario only. There are no sediment

guidelines exceedances for any of the

BAT/NSPS-models.

V. Best Management Practices (BMPs)

Alternatives to Numeric Limitations

and Standards

A. General

EPA is considering three options for

the final rule for the BAT limitation and

NSPS controlling SBF retained on

discharged cuttings: (1) a single numeric

discharge limitation with an

accompanying compliance test method;

(2) allowing operators to choose either

a single numeric discharge limitation

with an accompanying compliance test

method, or as an alternative, a set of

BMPs that employs limited cuttings

monitoring; or (3) allowing operators to

choose either a single numeric discharge

limitation with an accompanying

compliance test method or an

alternative set of BMPs that employ no

cuttings monitoring. Additionally, EPA

is considering two options in the final

rule for BAT limitation and NSPS for

controlling SBFs not associated with

SBF drill cuttings: (1) zero discharge; or

(2) allowing operators to choose either

zero discharge or an alternative set of

BMPs with an accompanying

compliance method.

EPA has initial data on the

effectiveness of BMPs for controlling

SBF-discharges (Farmer, 2000; Hanni et

al, 1998). The initial data on BMP

effectiveness was generated from over

12 deepwater projects in the North Sea

and 11 deepwater projects in the GOM.

Data from Farmer (2000) was received

by EPA just before publication of this

notice and was unable to be fully

analyzed. This data set represented

North Sea and GOM wells that did not

employ a cuttings dryer, however,

certain drilling projects in the data set

did use an extra technician (‘‘mud cop’’)

to assist in improving the efficiency of

the existing solids control equipment

through use of BMPs.

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21569

EPA is requesting additional data on

the use of BMPs to reduce or prevent

SBF-discharges. In particular, EPA

would like to see BMP documentation

associated with cuttings retention

spreadsheets similar to those submitted

to support the development of the

numeric guidelines and standards for

the retention of SBF on cuttings. EPA

will be using these data sets to

determine the effectiveness of BMPs and

their use as alternatives to numeric

limitations and standards. EPA may

select any of these BMP alternative

options or any combination of these

BMP alternative options in the final

rule.

Sections 304(e), 308(a), 402(a), and

501(a) of the Clean Water Act authorize

the Administrator to prescribe BMPs as

part of effluent limitations guidelines

and standards or as part of a permit.

EPA’s BMP regulations are found at 40

CFR 122.44(k). Section 304(e) of the

CWA authorizes EPA to include BMPs

in effluent limitation guidelines for

certain toxic or hazardous pollutants for

the purpose of controlling ‘‘plant site

runoff, spillage or leaks, sludge or waste

disposal, and drainage from raw

material storage.’’ Section 402(a)(1) and

NPDES regulations [40 CFR 122.44(k)]

also provide for best management

practices to control or abate the

discharge of pollutants when numeric

limitations and standards are infeasible.

In addition, section 402(a)(2), read in

concert with section 501(a), authorizes

EPA to prescribe as wide a range of

permit conditions as the Administrator

deems appropriate in order to ensure

compliance with applicable effluent

limitations and standards and such

other requirements as the Administrator

deems appropriate.

SBFs adhered to discharged cuttings

may contain barite (used as a weighting

agent in the drilling fluid system), and

can also be contaminated with

formation crude oil. Barite is a mineral

principally composed of barium sulfate,

however, barite ore is generally known

to have trace contaminants of several

heavy metals such as mercury,

cadmium, arsenic, chromium, copper,

lead, nickel, and zinc. Formation oil is

an ‘‘indicator’’ pollutant for the many

toxic and hazardous pollutant

components present in the formation

(crude) oil, such as aromatic and

polynuclear aromatic hydrocarbons.

These formation oil pollutants include

benzene, toluene, ethylbenzene,

naphthalene, phenanthrene, and

phenol. For a complete listing of

pollutants associated with SBF readers

should turn to Table VII–1 in the EPA

February 1999 proposal SBF

Development Document (EPA–821–B–

98–021). Many of these SBF pollutants

are designated as hazardous pollutants

under CWA section 307(a)(1), see 40

CFR. 410.15, and oil is a hazardous

substance under section 311 of the

CWA.

It should also be noted that many of

these same pollutants can also be found

in SBF discharges not associated with

cuttings (e.g., incidental spills,

accumulated solids, deck drainage).

Also, the drilling fluid (SBF based) can

contain barite and trace contaminants of

several heavy metals. Incidental spills of

SBF can release these toxic and

hazardous pollutants into the

environment. In addition,

approximately 75 barrels per well of

solids, of which up to 25% is SBF,

accumulate in the rig mud pits, sand

traps, and other equipment. These

accumulated solids may be discharged

during equipment cleaning operations.

SBF discharges such as spills and

leaks and accumulated solids may also

be co-mingled with deck drainage

which may also contain other toxic and

hazardous pollutants. Deck drainage

includes all water resulting from spills,

platform washings, deck washings, tank

cleaning operations and run-off from

curbs, gutters, and drains including drip

pans and work areas. Lists of pollutants

and pollutant concentrations, including

toxic and hazardous pollutants, in

untreated deck drainage are contained

in Tables X–17, X–18, and X–19 of the

Final Offshore Development Document

(EPA–821–R–93–003).

Therefore, the BMP alternatives to

numeric limitations and standards in

this notice are directed, among other

things, at preventing or otherwise

controlling leaks, spills, and discharges

of toxic and hazardous pollutants in

SBF cuttings and non-cuttings wastes.

B. BMP Alternatives for SBF Discharges

Associated with Cuttings

As previously stated, EPA is

considering three options for the final

rule for the BAT limitation and NSPS

controlling SBF retained on discharged

cuttings: (1) A single numeric discharge

limitation with an accompanying

compliance test method; (2) allowing

operators to choose either a single

numeric discharge limitation with an

accompanying compliance test method,

or as an alternative, a set of BMPs that

employs limited cuttings monitoring; or

(3) allowing operators to choose either

a single numeric discharge limitation

with an accompanying compliance test

method or an alternative set of BMPs

that employ no cuttings monitoring. The

BMP alternatives were developed with

input from EPA Regional permit writers

and industry. Under the third

alternative cuttings discharge, BMPs

option (i.e., cuttings not monitored),

EPA is also considering whether to

require as a BMP the use of a cuttings

dryer discussed above as representative

of BAT/NSPS or to make the use of a

cuttings dryer optional.

Some industry representatives have

expressed an interest in using BMPs that

are not demonstrated through limited

cuttings monitoring as equivalent to a

numeric cuttings retention limit to

control discharges of SBF associated

with cuttings. Two issues were

identified by the industry

representatives as a basis for their

support of using BMPs as an alternative

discharge limitation: (1) Low gravity

solids (or ‘‘fines’’) build-up in an active

mud system; and (2) engineering

limitations in the installation of cuttings

dryers and supporting equipment on

certain rigs. If operators are correct in

their assertion that setting a numeric

cuttings retention limit is infeasible,

EPA may use BMPs to control SBFwastes.

As discussed in the Development

Document for the February 1999

Proposal (EPA–821–B–98–021), solids

control equipment generally increases

the mechanical degradation of drill

solids (i.e., larger particles are broken

into smaller particles). An undesirable

increase in drilling fluid weight and

viscosity can occur when drill solids

degrade into fines that cannot be

removed by solids control equipment

[i.e., generally classified as < 5 microns

(10¥6 meters) in length]. An

unacceptable high fines content (i.e.,

generally > 5% of total drilling fluid

weight) may consequently lead to

drilling problems (e.g., undesirable

rheological properties, stuck pipe).

Therefore, it is possible that the

increased recovery of SBF from cuttings

for re-use in the active mud system,

often achieved through use of the

cuttings dryer in solids control systems,

may lead to a build-up in fines for

certain formation characteristics (e.g.,

high reactivity of formation cuttings,

limited loss of drilling fluid into the

formation).

In order to meet EPA’s proposed

numeric cuttings retention value where

there are unfavorable formation

characteristics, operators may be limited

to: (1) Diluting the fines in the active

mud system through the addition of

‘‘fresh’’ SBF; and/or (2) capturing a

portion of the fines in a container and

sending the fines to shore for disposal.

One SBF manufacturer stated in a verbal

conversation with EPA that over the

course of the past year (1999), a

Canadian operator generated 12,000

barrels of SBF which had a fines content

21570 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

that rendered it unusable and

untreatable for future drilling

applications.

Currently, however, EPA does not

have documentation that the build-up of

fines in SBF drilling is a widespread

problem in the United States or one that

cannot be handled by operators in the

United States. The absence of

documented fines build-up problems in

the GOM may be due to a sufficient loss

of SBF drilling fluid with fines downhole. This loss of fluid into the

formation would require the addition of

fresh SBF drilling fluid and minimize

the build-up of fines. In addition,

drilling rigs are now being designed and

constructed to incorporate cuttings

dryer and fines removal equipment into

the solids control system. EPA is

requesting data and comments on the

expected frequency and conditions

where operators are not able to meet

EPA’s new proposed SBF numeric

cuttings retention numbers (see section

IV.C.5) based on fines build-up in the

active mud system.

Some industry representatives have

also suggested that some rigs are

incapable of installing the equipment

needed to meet EPA’s proposed numeric

cuttings retention limit (e.g., cuttings

dryers, fines removal equipment). EPA

staff visited two offshore GOM rigs

where cuttings dryer and fines removal

equipment was and was not able to be

installed successfully into the existing

solids control equipment system. The

cuttings dryer that was able to be

installed into the existing solids control

system was smaller than the other

cuttings dryer system on the other

visited rig. Moreover, the successful

installation also relied on an auger

transport system for moving cuttings

from the existing solids control system

to the new cuttings dryer and fines

removal equipment. The key cuttings

dryer and fines removal equipment

installation limitations appear to be

whether rigs can install cuttings dryers

and fines removal equipment near the

existing solids control units and

whether an auger cuttings transport

system can be used to move cuttings

from the existing solids control units to

the new equipment. EPA’s site visit and

statements by industry representatives

give differing viewpoints on how many

rigs cannot incorporate new equipment

to meet EPA’s proposed cuttings

retention number. Therefore, EPA

requests further information and data to

identify the name and number of rigs

that cannot incorporate new equipment

to meet EPA’s cuttings retention

number.

C. BMP Alternatives for SBF Discharges

Not Associated with Cuttings

As previously stated, EPA is

considering two options in the final rule

for BAT limitation and NSPS for

controlling SBFs not associated with

SBF drill cuttings: (1) zero discharge; or

(2) allowing operators to choose either

zero discharge or an alternative set of

BMPs with an accompanying

compliance method. The follow sections

describe several types of SBF discharges

not associated with cuttings that can be

controlled through either zero discharge

or a set of BMPs. At this time, EPA’s

preferred option for these SBF noncuttings wastes is to give operators the

choice of selecting either zero discharge

or using a set of BMPs to control these

discharges (Option 2 identified above).

This approach would give operators the

flexibility of selecting a single numeric

effluent limitation or a set of BMPs

designed for their respective facility.

1. Accumulated Solids

Accumulated solids is one example of

a non-cuttings SBF discharge. Industry

representatives have stated that industry

is split on the practice of discharging

accumulated solids with some

discharging accumulated solids

provided permit limitations and

standards are met and others opting to

haul this material to shore for disposal

(see section II.B.3). Approximately 75

barrels per well of fine solids and barite,

of which up to 25% is SBF, accumulate

in the rig mud pits, sand traps, and

other equipment. Several hundred

barrels (approximately 200 to 400

barrels) of water are used to wash out

the mud pits. Industry representatives

also indicated that those oil and gas

extraction operations that discharge

wash water and accumulated solids first

recover free SBF.

Industry has submitted to EPA Region

6 and EPA Headquarters a list of BMPs

that can minimize these discharges.

Accordingly, Industry may wish to

select BMPs as the method for

controlling these discharges instead of

zero discharge.

2. SBF Spills During Drilling Operations

Industry also noted that BMPs are

already in place on most rigs to prevent

spills during connections and

disconnections of the drill string.

Typical waste minimizing techniques

include slugging the pipe (a small

volume of heavy mud is pumped into

the drill pipe to create a hydrostatic

differential inside the drill pipe) with

heavy mud. Rubber wipers may also be

used on the inside and outside of the

drill pipe to remove any residual mud

before racking the pipe in the derrick

(i.e., storing the pipe on the rig). In some

cases, the mud is captured with mud

buckets and returned to the active mud

system. Any spills on the rig floor can

also be squeegeed back through the

rotary into the mud system. A mud

vacuum is also sometimes used. Pipe

racks and the rig floor may also be

designed with drip pans underneath to

capture any remaining spillage.

Captured fluid may go to the rig’s oil/

water sump for treatment and possible

recovery. Industry estimated that

essentially all of the SBF that spills on

the rig floor is recovered using the

controls described above. The amount of

SBF spilled on the rig floor that is not

captured by current practices is

estimated by industry to be less than 1

gallon SBF per 100 feet drilled.

Industry may wish to select BMPs as

the method for controlling these

discharges instead of zero discharge.

D. Implementation of BMP Alternative

(the BMP Plan)

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,

EPA solicits comments on a BMP Plan

requirement as a component of BMPs as

an alternative to a numeric limitation or

standard.

A BMP Plan would not be required if

operators did not use BMPs to control

SBF discharges. Moreover, EPA is

proposing that operators be allowed to

choose whether one or both of the two

SBF wastestream (i.e., SBF discharges

associated with cuttings, SBF discharges

not associated with cuttings) be

managed through the BMP alternatives.

Accordingly, EPA is also proposing

that operators only be required to

develop and implement a BMP Plan for

those SBF wastestreams it elects to

manage through the BMP alternatives.

Moreover, EPA is proposing that

operators only be required to develop

one BMP Plan if it elects to manage both

SBF wastestreams (e.g., discharges

associated with cuttings and SBF

discharges not associated with cuttings)

through use of the BMP alternatives. As

there are common elements in BMP

Plans that cover both SBF wastestreams,

EPA has grouped common elements

together and identified specific

elements for specific SBF wastestreams

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21571

in separate sections. Table V.D.1 is a

guide on what BMP Plan elements are

required for the different BMP

alternatives.

The SBF BMP common elements 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. EPA feels that

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.

TABLE V.D.1: BMP PLAN ELEMENTS REQUIRED FOR THE DIFFERENT BMP ALTERNATIVES TO SBF NUMERIC EFFLUENT

LIMITATIONS GUIDELINES AND STANDARDS

BMP plan alternatives a

SBF wastestreams operator elects to manage with BMP alternatives

BMP plan elements e (listed by section of this

notice) SBF discharges not

associated with

cuttings b

SBF discharges associated with cuttings

(no monitoring) c

SBF discharges associated with cuttings

(monitoring) d

1 ................................. X Sec. V.D.1 to 5,6.

2 ................................. X X Sec. V.D.1 to 5,6,7.

3 ................................. X X Sec. V.D.1 to 5,6,8.

4 ................................. X Sec. V.D.1 to 5,7.

5 ................................. X Sec. V.D.1 to 5,8.

aOperators that elect to meet numeric limitations and standards are not required to develop BMPs or a BMP Plan.

bThis includes incidental SBF spills, accumulated solids, and deck drainage (see section V.C). cThis includes SBF discharges associated with cuttings with no equivalency determination through monitoring (see section V.B). dThis includes SBF discharges associated with cuttings with an equivalency determination through monitoring (see section V.B). eOperators are only required to develop one BMP Plan if the operator elects to manage both SBF wastestreams (e.g., discharges associated

with cuttings and SBF discharges not associated with cuttings) through use of the BMP alternatives.

1. SBF BMP Plan Purpose and

Objectives

The BMP Plan must be designed to

prevent or minimize the generation and

the potential for the discharge of SBF

from the facility to the waters of the

United States through normal

operations and ancillary activities. The

Permittee must establish specific

objectives for the control of SBF by

conducting the following evaluations:

a. The Permittee should identify

which SBF wastestreams (i.e., cuttings

related or non-cuttings related) are to be

controlled through use of the BMP

alternatives and which SBF

wastestreams are to be controlled

through use of numeric effluent

limitation guidelines and standards.

b. Each facility component or system

controlled through use of BMP

alternatives must be examined for its

SBF-waste minimization opportunities

and its potential for causing a discharge

of SBF to waters of the United States

due to equipment failure, improper

operation, natural phenomena (e.g.,

rain, snowfall).

c. For each SBF wastestream

controlled through BMP alternatives

where experience indicates a reasonable

potential for equipment failure (e.g., a

tank overflow or leakage), natural

condition (e.g., precipitation), or other

circumstances to result in SBF reaching

surface waters, the BMP Plan should

include a prediction of the direction,

rate of flow and total quantity of SBF

which could be discharged from the

facility as a result of each condition or

circumstance.

2. Requirements

The BMP Plan must be consistent

with the objectives in section V.D.1. The

BMP Plan may reflect requirements

within spill response plans required by

the Minerals Management Service (see

30 CFR 254) or other Federal or State

requirements and incorporate any part

of such plans into the BMP Plan by

reference.

The Permittee must certify that its

BMP Plan is complete, on-site, and

available upon request to EPA or the

NPDES Permit controlling authority.

This certification should identify the

NPDES permit number and be signed by

an authorized representative of the

Permittee. For new exploratory

operations, the certification should be

submitted no later than the written

notice of intent to commence discharge.

For existing dischargers, the

certification should be submitted within

one year of permit issuance. The BMP

Plan must:

a. Be documented in narrative form,

and must include any necessary plot

plans, drawings or maps, and must be

developed in accordance with good

engineering practices. At a minimum,

the BMP Plan must 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).

b. Include the following provisions

concerning BMP Plan review:

(i) Be reviewed by plant engineering

staff and the plant manager as warranted

by changes in the operation or at the

facility which are covered by the BMP.

(ii) Be reviewed and endorsed by the

individuals responsible for development

and implementation of the BMP Plan.

Such review and endorsement may be

performed by the establishment of a

program of documented initial and

annual refresher training of drilling

equipment operators, maintenance

personnel, and other technical and

supervisory personnel who have

responsibility for operating,

maintaining, or supervising the

operation and maintenance of drilling

equipment.

(iii) Include a statement that the above

reviews have been completed and that

the BMP Plan fulfills the requirements

set forth in this section of the notice.

The statement must be certified by the

dated signatures of the individuals

responsible for development and

implementation of the BMP Plan.

c. Establish specific best management

practices to meet the objectives

identified in section V.D.1, addressing

each component or system capable of

generating or causing a release of

significant amounts of SBF, and

identifying specific preventative or

remedial measures to be implemented.

3. Documentation

The Permittee must maintain a copy

of the BMP Plan and related

documentation (e.g., training

certifications, summary of the

monitoring results, records of SBFequipment spills, repairs, and

maintenance) at the facility and must

make the BMP Plan and related

21572 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

documentation available to EPA or the

NPDES Permit controlling authority

upon request. Submission of the BMP

Plan and related documentation shall be

at the frequency established by the

NPDES permit control authority (i.e.,

Permit monitoring reports), but in no

case less than once per five years.

4. BMP Plan Modification

For those SBF wastestreams

controlled through BMP alternatives,

the Permittee must 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 SBF-wastes or their

release or potential release to the

receiving waters. At a minimum the

BMP Plan must be reviewed once every

five years and amended within three

months if warranted. Any such changes

to the BMP Plan must be consistent with

the objectives and specific requirements

listed above. All changes in the BMP

Plan must be reviewed by the plant

engineering staff and plant manager.

5. Modification for Ineffectiveness

At any time, if the BMP Plan proves

to be ineffective in achieving the general

objective of preventing and minimizing

the generation of SBF-wastes and their

release and potential release to the

receiving waters and/or the specific

requirements above, the permit and/or

the BMP Plan must be subject to

modification to incorporate revised

BMP requirements.

6. Specific Pollution Prevention

Activities for SBF Discharges Not

Associated With Cuttings

An approved BMP Plan may include

the following examples of specific

pollution prevention activities for

controlling SBF discharges not

associated with cuttings.

a. Establishing programs for

identifying, documenting, and repairing

leaking SBF equipment, tracking SBF

equipment repairs, and training

personnel to report and evaluate SBF

spills, as detailed in section V.E.2.c and

V.E.2.d below.

b. Establishing programs for

identifying, documenting, and repairing

malfunctioning SBF equipment,

tracking SBF equipment repairs, and

training personnel to report and

evaluate malfunctioning SBF

equipment.

c. Recovering and returning to the

process or an appropriate storage

container to the maximum extent

practicable spilled or leaked drilling

fluids to prevent their discharge.

d. Immediately recovering spills of

drilling fluid on the drill floor using a

vacuum, grated trough, or comparable

system.

e. Providing adequate containment for

SBF spills on the drill deck to minimize

potential spills.

f. Establishing mud pit and equipment

cleaning methods in such a way as to

minimize the potential for drilling

fluids discharges, including but not

limited to the following:

(i) Ensuring proper operation and

efficiency of mud pit agitation

equipment.

(ii) Using mud gun lines during

mixing to provide agitation in dead

spaces to minimize solids accumulation.

(iii) Pumping drilling fluids off for

use, recycle, or disposal before using

wash water to dislodge solids.

(iv) Limiting the volume of wash

water used to the minimum needed to

dislodge and slurry solids for overboard

discharge.

(v) Using water-minimizing

techniques (e.g., steam or compressed

air) where possible to clean the sides of

the mud pit.

g. The Permittee must also include the

number and dates of non-cuttings SBFdischarges managed by BMPs in their

NPDES permit reports. The description

of these discharges must also include

estimated volume of SBF discharged

and any corrective actions taken to

respond to such non-cuttings SBFdischarges.

7. Specific Pollution Prevention

Activities for SBF Discharges Associated

With Cuttings (No-Verification Cuttings

Monitoring)

The following specific pollution

prevention activities are required in a

BMP Plan when operators elect to

control SBF discharges associated with

cuttings by a set of BMPs where no

equivalency determination is made

through limited cuttings monitoring.

a. Establishing programs for

identifying, documenting, and repairing

malfunctioning SBF equipment,

tracking SBF equipment repairs, and

training personnel to report and

evaluate malfunctioning SBF

equipment.

b. Establishing operating and

maintenance procedures for each

component in the solids control system

in a manner consistent with the

manufacturer’s design criteria for flow,

fluid type, density, and rheological

properties, which may include, but are

not limited to, the following:

(i) Maintaining shale shakers such

that units have adequate capacity for

circulating the active drilling fluid

volume, have screens of such mesh size

that no more than 75% of screen area is

wet, and maintain the manufacturer’s

design screen tension, maximum ‘‘G’’

force, maximum positive screen deck

angle, and maximum vibrator assembly

angle to screen deck;

(ii) Maintaining centrifuges such that

units have sufficient capacity for active

drilling fluid volume (note: for most

situations where 8.5′′ or larger hole sizes

are drilled, multiple units may be

required), have bowl revolutions per

minute (RPM) adjusted as high as

practical to maximize ‘‘G’’ force, have

bowl/conveyor RPM differential

minimized to subject cuttings to ‘‘G’’

Force for the maximum time period

before leaving the unit, have feed tube

adjusted to introduce cuttings to the

maximum bowl diameter as they enter

the unit, and have processing rates

closely monitored to maximize cuttings

discharge with minimum SBF retention.

c. Using gel pills or other applicable

measures in order to minimize

contamination of drilling fluids when

changing from water-based to nonaqueous based drilling fluids and vice

versa.

d. Sending interface muds through the

mud recovery system prior to discharge

or disposal.

8. Specific Pollution Prevention

Activities for SBF Discharges Associated

With Cuttings (Verification Cuttings

Monitoring)

The following specific pollution

prevention activities are required in a

BMP Plan when operators elect to

control SBF discharges associated with

cuttings by a set of BMPs that are

demonstrated, through limited cuttings

monitoring, to meet the same level of

control as the BAT/NSPS cuttings

retention limit.

a. All the specific pollution

prevention activities in section V.D.7

b. A daily retort analysis must be

performed (in accordance with

Appendix 7 to Subpart A of Part 435)

during the first 0.33 X days where X is

the anticipated total time (in days) to

drill that particular well. The retorts

analyses will be documented in the well

retort log.

(i) When the arithmetic average of the

cuttings retort analyses is less than the

numeric cuttings retention limitation

and standard, monitoring of cuttings

may cease for that individual well.

(ii) When the arithmetic average of the

cuttings retort analyses is greater than

the numeric cuttings retention

limitation and standard, monitoring will

continue for the second 0.33X days

where X is the anticipated total time (in

days) to drill that particular well. If after

the second 0.33X, the arithmetic average

of the cuttings retort analyses is still

greater than numeric cuttings retention

Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules 21573

limitation and standard then monitoring

will continue for the remainder of the

well operation. Moreover, this incident

will be reported within one week to

EPA or the NPDES Permit controlling

authority for review and

recommendations.

c. The Permittee must also include the

cuttings monitoring data and dates of

monitored and non-monitored SBFcuttings discharges managed by BMPs

in their NPDES permit reports.

E. Paperwork Reduction Act

Requirements Related to BMPs

Alternatives

The information collection

requirements related to the BMP

alternatives in this notice have been

submitted for approval to the Office of

Management and Budget (OMB) under

the Paperwork Reduction Act, 44 U.S.C.

3501 et seq. An Information Collection

Request (ICR) document has been

prepared by EPA (ICR No. 1953.01) and

a copy may be obtained from Sandy

Farmer by mail at Collection Strategies

Division, U.S. Environmental Protection

Agency (2822), 1200 Pennsylvania Ave.,

NW, Washington, DC 20460; by e-mail

at farmer.sandy@epa.gov, or by calling

(202) 260–2740. A copy may be

downloaded from the Internet at http:/

/www.epa.gov/icr.

The BMP alternatives identified in

this notice include information

collection requirements that are

intended to control the discharges of

SBF in place of numeric effluent

limitations and standards. These

information collection requirements

include, for example: (1) Training

personnel; (2) analyzing spills that

occur; (3) identifying equipment items

that might need to be maintained,

upgraded, or repaired; (4) identifying

procedures for waste minimization; (4)

performing monitoring (including the

operation of monitoring systems) to

establish equivalence with a numeric

cuttings retention limitation and to

detect leaks, spills, and intentional

diversion; and (5) generally to

periodically evaluate the effectiveness

of the BMP alternatives.

The BMP alternatives also require

operators to develop and, when

appropriate, amend plans specifying

how operators will implement the

specified BMP alternatives, and to

certify to the permitting authority that

they have done so in accordance with

good engineering practices and the

requirements of the regulation. The

purpose of those provisions is,

respectively, to facilitate the

implementation of BMP alternatives on

a site-specific basis and to help the

regulating authorities to ensure

compliance without requiring the

submission of actual BMP Plans.

Finally, the recordkeeping provisions

are intended to facilitate training, to

signal the need for different or more

vigorously implemented BMP

alternatives, and to facilitate compliance

assessment.

EPA has structured the BMP

alternatives to provide maximum

flexibility to the regulated community

and to minimize administrative burdens

on National Pollutant Discharge

Elimination System (NPDES) permit

authorities that regulate oil and gas

extraction facilities. Although EPA does

not anticipate that operators will be

required to submit any confidential

business information or trade secrets as

part of this ICR, all data claimed as

confidential business information will

be handled by EPA pursuant to 40 CFR

Part 2.

For the five SBF BMP alternatives (see

Table V.D.1), the public reporting

burdens range from an estimated 515

hours per respondent per year [i.e.,

(12,500 initial hours/3 years + 21,604

annual hours/year)/50 SBF well

operators] to 1,363 hours per respondent

per year [i.e., (17,500 initial hours/3

years + 62,334 annual hours/year)/50

SBF well operators]. EPA also estimated

the annual burden for EPA Regions, the

NPDES permit controlling authorities, to

review BMPs and ensure compliance.

EPA estimates that essentially all of the

SBF discharges will occur in Federal

offshore waters or in Cook Inlet, Alaska,

where EPA Region X retains NPDES

permit controlling authority. The EPA

Regional burden for reviewing BMP

Plans is estimated at 5.7 hours per year

[i.e., (8 initial hours/3 years + 3 annual

hours/year)/50 SBF well operators].

For new exploratory operations, the

certification of BMP Plan completion

should be submitted to the permit

control authority no later than the

written notice of intent to commence

discharge. For existing dischargers, the

certification should be submitted within

one year of permit issuance. In addition,

a copy of the completed BMP Plan may

be requested by the NPDES permit

control authority at any time.

Submission of records to the permit

control authority demonstrating

periodic review of the BMP Plan are due

at a minimum once every five years.

Monitoring reports demonstrating

compliance with the BMP Plan are due

to the permit control authority at the

frequency set by the permit control

authority (e.g., monthly or annually)

and may be requested by the permit

control authority on demand. Re-fresher

training certifications demonstrating

compliance with the BMP Plan are due

to the permit control authority at the

frequency set by the permit control

authority (e.g., semi-annually) and may

be requested by the permit control

authority on demand.

For the five SBF BMP alternatives (see

Table V.D.1), the public reporting costs

range from approximately $18,600 per

respondent per year [i.e., ($921,875

initial costs/3 years + $623,625 annual

costs/year)/50 SBF well operators] to

$38,000 hours per respondent per year

[i.e., ($1,290,625 initial costs/3 years +

$1,465,100 annual costs/year)/50 SBF

well operators]. The EPA Regional costs

for reviewing BMP Plans is estimated at

approximately $180 per year [i.e.,

($12,800 initial costs/3 years + $4,800

annual costs/year) / 50 SBF well

operators].

21574 Federal Register / Vol. 65, No. 78 / Friday, April 21, 2000 / Proposed Rules

Burden means the total time, effort, or

financial resources expended by persons

to generate, maintain, retain, or disclose

or provide information to or for a

Federal agency. This includes time

needed to: review instructions; develop,

acquire, install, and utilize technology

and systems for the purposes of

collecting, validating, and verifying

information, processing and

maintaining information and disclosing

and providing information; adjust the

existing ways to comply with previously

applicable instructions and

requirements; train personnel to be able

to respond to the collection of

information; search data sources;

complete and review the collection of

information; and transmit or otherwise

disclose the information.

An agency may not conduct or

sponsor, and a person is not required to

respond to, a collection of information

unless it displays a currently valid OMB

control number. The OMB control

numbers for EPA’s regulations are listed

in 40 CFR Part 9 and 48 CFR Chapter

15.

Comments are requested on the

Agency’s need for this information, the

accuracy of the provided burden

estimates, and any suggested methods

for minimizing respondent burden,

including through the use of automated

collection techniques. Send comments

on the ICR to the Director, Collection

Strategies Division; U.S. Environmental

Protection Agency (2822); 1200

Pennsylvania Ave., NW, Washington,

DC 20460; and to the Office of

Information and Regulatory Affairs,

Office of Management and Budget, 725

17th St., NW, Washington, DC 20503,

marked ‘‘Attention: Desk Officer for

EPA.’’ Include the ICR number in any

correspondence. Since OMB is required

to make a decision concerning the ICR

between 30 and 60 days after April 21,

2000, a comment to OMB is best assured

of having its full effect if OMB receives

it by May 22, 2000. The final rule will

respond to any OMB or public

comments on the information collection

requirements contained in this notice.

Dated: April 12, 2000.

J. Charles Fox,

Assistant Administrator for Water.

[FR Doc. 00–9655 Filed 4–20–00; 8:45 am]

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