# Hazardous Waste Management System; Identification and Listing of Hazardous Waste: Petroleum Refining Process Wastes; Land Disposal Restrictions for Newly Identified Wastes; and CERCLA Hazardous Substance Designation and Reportable Quantities

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URL: https://www.frixlaw.com/law-library/documents/fr%3A95-27693

## Record

- **Collection:** Federal Register
- **Document type:** Proposed Rule
- **Published:** November 20, 1995
- **Citation:** 60 FR 57747

## Text

SUMMARY: The U.S. Environmental Protection Agency (EPA) is proposing to
amend the regulations for hazardous waste management under the Resource
Conservation and Recovery Act (RCRA) by listing, as hazardous wastes,
three residuals from petroleum refining processes because certain
disposal practices may present a risk to human health or the
environment. EPA is also proposing not to list as hazardous eleven
process residuals. This action proposes to add the toxic constituents
found in the wastes to the list of constituents that serves as the
bases for classifying wastes as hazardous.
This action is proposed pursuant to RCRA section 3001(b) and
section 3001(e)(2), which direct EPA to make a hazardous waste listing
determination for ``refining wastes.'' The effect of this proposed
regulation would be to subject these wastes to regulation as hazardous
wastes under Subtitle C of RCRA. Additionally, this action proposes to
designate the wastes proposed for listing as hazardous substances
subject to the Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA), and to adjust the one-pound statutory
reportable quantities (RQs) for these substances.
In support of the Agency's regulatory reinvention efforts, this
action also proposes changes to the RCRA regulations to promote the
environmentally sound recycling of oil-bearing residuals. Specifically,
the Agency is proposing to broaden the existing exemption for certain
wastes from the definition of solid waste. These include oil-bearing
residuals from specified petroleum refining sources inserted into the
petroleum refining process, and spent caustic from liquid treating
operations when used as a feedstock. Today's proposal also would exempt
from the definition of hazardous waste mixtures of clarified slurry oil
(CSO) storage tank sediment and/or in-line filter/separation solids
with tank wastewaters, provided that the waste is discharged to the oil
recovery sewer before primary oil/water/solids separation, and ceramic
support media separated from spent hydrotreating/hydrorefining
catalysts.
Finally, EPA is proposing to apply universal treatment standards
(UTS) under the Land Disposal Restrictions program to the Petroleum
Refining Wastes proposed for listing in this rulemaking.

DATES: EPA will accept public comments on this proposed rule until
February 20, 1996. Comments postmarked after this date will be marked
``late'' and may not be considered. Any person may request a public
hearing on this proposal by filing a request with Mr. David Bussard,
whose address appears below, by December 4, 1995.

ADDRESSES: The official record of this rulemaking is identified by
Docket Number F-95-PRLP-FFFFF. The public must send an original and two
copies (and a voluntary copy on a computer diskette) of their comments
to: EPA RCRA Docket Clerk (5305W), U.S. Environmental Protection
Agency, 401 M Street, SW., Washington, D.C. 20460. Place the docket
number F-95-PRLP-FFFFF on your comments. Through November 13, 1995,
copies of materials relevant to this proposed rulemaking are located in
the docket at the address listed above. The Agency plans to relocate
the docket on November 14, 1995, and the docket will be physically
closed from November 14, 1995 to November 26, 1995. Special
arrangements for reviewing docket materials during this time can be
made by calling (202) 260-9327. The Agency will be issuing a separate
Federal Register notice explaining this change.
Starting November 27, 1995, the EPA RCRA Docket will be located at
Crystal Gateway #1, 1st Floor, 1235 Jefferson Davis Highway, Arlington,
VA. Comments may be delivered to that location. The docket is open from
9:00 a.m. to 4:00 p.m., Monday through Friday, excluding Federal
holidays. The public can make an appointment to review docket materials
by calling (202) 260-9327. Starting November 27, 1995, the new
telephone number for the docket will be (703) 603-9230. The public may
copy 100 pages from the docket at no charge; additional copies are
$0.15 per page.
Requests for a hearing should be addressed to Mr. David Bussard at:
Hazardous Waste Identification Division, Office of Solid Waste (5304),
U.S. Environmental Protection Agency, 401 M Street, SW., Washington,
D.C. 20460.

FOR FURTHER INFORMATION CONTACT: The RCRA/Superfund Hotline, toll-free,
at (800) 424-9346 or at (703) 920-9810. The TDD Hotline number is (800)
553-7672 (toll-free) or (703) 486-3323 in the Washington, D.C.
metropolitan area. For technical information on the RCRA hazardous
waste listings, contact Maximo Diaz, Jr., Office of Solid Waste (5304),
U.S. Environmental Protection Agency, 401 M Street, SW, Washington,
D.C., 20460, (202) 260-4786.
For technical information on the CERCLA aspects of this rule,
contact: Mr. Jack Arthur, Response Standards and Criteria Branch,
Emergency Response Division (5202G), U.S. Environmental Protection
Agency, 401 M Street, SW, Washington, D.C. 20460, (703) 603-8760.

SUPPLEMENTARY INFORMATION: The contents of the preamble to this
proposed rule are listed in the following outline:

I. Legal Authority
II. Background
A. Schedule Suit
B. Existing Petroleum Refining Listings and Other Relevant
Agency Actions
1. Listings
2. Definition of Solid Waste Exemptions
C. EPA's Hazardous Waste Listing Determination Policy
III. Today's Action
A. Summary of Today's Action
1. Summary of Listing Determinations

[[Page 57748]]

2. Summary of Definition of Solid Waste and Other Exemptions
Proposed in Today's Notice
B. Description of the Industry
C. Overview of EPA's Information Collection Activities
1. Field Investigations and Sampling
2. RCRA Sec. 3007 Survey
D. Description of the Process Residuals in Comparison With the
Consent Decree Language
E. Hazardous Oil-bearing Residuals Returned to Refinery
Processes
1. Background
2. Proposed Amendments to Address Hazardous Residuals Returned
to the Refining Process
F. Description of Health and Risk Assessments
1. Human Health Criteria and Effects
2. Risk Analysis
3. Consideration of Uncertainty in Listing Determinations
4. Peer Review
G. Waste-specific Listing Determination Rationales
1. Crude Oil Storage Tank Sediment
2. Clarified Slurry Oil (CSO) Tank Sediment and/or In-line
Filter/Separation Solids
3. Catalyst from Hydrotreating
4. Catalyst from Hydrorefining
5. Catalyst from Sulfuric Acid Alkylation
6. Spent Caustic from Liquid Treating
7. Off-specification Product and Fines from Thermal Processes
8. Catalyst and Fines from Catalytic Cracking
9. Sludge from Hydrofluoric Acid Alkylation
10. Sludge from Sulfur Complex and H2S Removal Facilities
11. Catalyst from Sulfur Complex and H2S Removal Facilities
12. Unleaded Gasoline Storage Tank Sediment
13. Catalyst from Reforming
14. Sludge from Sulfuric Acid Alkylation
H. Request for Comments on Options for Conditional Exemptions
1. Legal Basis for Conditional Exemptions
2. Improvements in Risk Assessment Methodology
3. Options for Conditional Exemptions
I. Impacts on Idled Units
J. Third Party Regeneration/Reclamation of Spent Petroleum
Catalyst
1. Exemption under Sec. 266.100(b)
2. Catalyst Support Media
3. Residuals Generated from Petroleum Catalyst Regeneration/
Reclamation
K. Headworks Exemption
IV. Waste Minimization
A. Crude Oil Storage Tank Sediment
B. Clarified Slurry Oil (CSO) Tank Sediment and/or In-line
Filter/Separation Solids
C. Catalyst from Hydrotreating
D. Catalyst from Hydrorefining
V. Applicability of the Land Disposal Restrictions Determinations
A. Request for Comment on the Agency's Approach to the
Development of BDAT Treatment Standards
B. Treatment Standards for the Newly Proposed Listed Petroleum
Refining Wastes
1. Identification of Wastes
2. Proposed Treatment Standards
3. Determination of BDAT
C. Capacity Determination for the Newly Proposed Listed
Petroleum Refining Wastes
1. Introduction
2. Capacity Analysis Results Summary
VI. Environmental Justice and Population Risk
A. Applicability of Executive Order 12898
B. Potential Effects
C. Population Risk
1. Results
VII. Compliance Dates
A. Notification
B. Interim Status and Permitted Facilities
VIII. State Authority
A. Applicability of Rule in Authorized States
B. Effects on State Authorizations
IX. CERCLA Designation and Reportable Quantities
A. Reporting Requirements
B. Basis for RQs and Adjustments
C. Alternative Method
X. Regulatory Requirements and Economic Analysis
A. Regulatory Requirements
1. Executive Order 12866
2. The Regulatory Flexibility Act of 1980
3. Paperwork Reduction Act
4. Unfunded Mandates Reform Act
B. Economic Impact Analysis
1. Costs of Compliance
2. Economic Impact Analysis
3. Cost Effectiveness of Individual Risk Reduction
4. Cost Effectiveness of Population Risk Reduction
5. Other Benefits Considered
XI. Paperwork Reduction Act

I. Legal Authority

Today's regulations are being proposed under the authority of
sections 2002(a) and 3001(b)(1) and (e)(2) of the Solid Waste Disposal
Act, as amended, 42 U.S.C. 6912(a), and 6921(b) and (e)(1), (commonly
referred to as RCRA), and section 102(a) of the Comprehensive
Environmental Response, Compensation, and Liability Act of 1980
(CERCLA), 42 U.S.C. 9602(a).

II. Background

A. Schedule Suit

In 1989, the Environmental Defense Fund (EDF) sued the Agency, in
part, for failing to meet the statutory deadlines of section 3001(e)(2)
of RCRA (EDF v. Browner; Civ. No. 89-0598 D.D.C.). To resolve most of
the issues in the case, EDF and EPA entered into a consent decree which
was approved by the court on December 9, 1994. The consent decree sets
out an extensive series of deadlines for promulgating RCRA rules and
for completing certain studies and reports. Paragraph 1.k of the
consent decree obligates the EPA to promulgate a final listing
determination on or before October 31, 1996, for the following
petroleum refining process residuals: clarified slurry oil sludge
1 from catalytic cracking, crude storage tank sludge, catalyst
from catalytic hydrotreating, process sludge from sulfur complex and
H2S removal facilities, off-spec product and fines from thermal
processes, catalyst from catalytic reforming, unleaded storage tank
sludge, catalyst from catalytic hydrorefining, catalyst and fines from
catalytic cracking, catalyst from sulfur complex and H2S removal
facilities, spent caustic from liquid treating, catalyst from
H2SO4 alkylation, sludge from HF alkylation, and sludge from
H2SO4 alkylation. Today the EPA is proposing listing
determinations for these residuals in accordance with the consent
decree's deadline for this rulemaking proposal.

\1\ While the consent decree uses the term ``sludge'' to refer
to any solid, semi-solid, or liquid residual, the term is defined
more narrowly for RCRA Subtitle C (Sec. 260.10). Throughout today's
proposal the Agency has used the term ``sediment'' to denote solid,
semi-solid, or liquid residuals deposited from industrial process
liquids.
---------------------------------------------------------------------------

B. Existing Petroleum Refining Listings and Other Relevant Agency
Actions

1. Listings
A number of wastes from petroleum refineries have been previously
listed as hazardous. The Agency notes that today's proposal does not
affect the scope of the existing hazardous waste listings (described
below) or the applicability of CERCLA to these wastes. EPA is not
soliciting comments concerning these listings and does not intend to
respond to any such comments received.
In addition, EPA-classified listed hazardous wastes are hazardous
substances under the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 (CERCLA), as amended. CERCLA
hazardous substances are listed in Table 302.4 at 40 CFR 302.4 along
with their reportable quantities (RQs), and include the listed
hazardous wastes from petroleum refining in Table II-1.

[[Page 57749]]
Table II-1.--List of Currently Regulated RCRA Wastes and CERCLA
Hazardous Substances and Reportable Quantities
------------------------------------------------------------------------
Statutory
Hazardous substance RQ pounds Final RQ
(kg) pounds (kg)
------------------------------------------------------------------------
K048--Dissolved air flotation (DAF) float from
the petroleum refining industry.............. 1(.454) 10(4.54)
K049--Slop oil emulsion solids from the
petroleum refining industry.................. 1(.454) 10(4.54)
K050--Heat exchange bundle cleaning sludge
from the petroleum refining industry......... 1(.454) 10(4.54)
K051--API separator sludge from the petroleum
refining industry............................ 1(.454) 10(4.54)
F037--Petroleum refinery primary oil/water/
solids sludge................................ 1(.454) 1(.454)
F038--Petroleum refinery secondary
(emulsified) oil/water/solids separation
sludge....................................... 1(.454) 1(.454)
------------------------------------------------------------------------

2. Definition of Solid Waste Exemptions
The jurisdictional boundaries of RCRA are established primarily by
the definition of solid waste, i.e., materials are subject to
regulation under RCRA only if they meet the regulatory definition of
solid waste. Secondary materials, including those EPA today is
proposing to list as hazardous, may be excluded from the definition of
solid waste and therefore from regulation under RCRA if they are
recycled in certain ways. Today's notice describes how each material is
typically managed. The notice also discusses existing regulatory
exclusions that may apply to a particular refining residual, depending
on how that residual is managed.
It is important to note that EPA is currently evaluating the
existing RCRA regulatory program, with emphasis on the need to clarify
RCRA jurisdiction, particularly as it applies to secondary materials
destined for recycling. Additionally, the Agency plans to develop a
simpler, more streamlined approach to regulating hazardous waste
recycling. One of the Agency's goals in revising the RCRA regulations
is to address outstanding jurisdictional issues that specifically
affect the petroleum refining industry. The petroleum industry poses
unique regulatory issues largely because existing exclusions from the
definition of solid waste generally do not apply to secondary materials
used to produce fuels, the primary product of the refining industry.
The current definition of solid waste at 40 CFR 261.2 classifies
secondary materials destined for recycling as solid wastes if the
recycling is a form of waste management. Conversely, if the materials
are recycled as part of an ongoing manufacturing process, they are not
solid wastes. Accordingly, the existing rules specifically exclude
secondary materials from the definition of solid waste that are: used
directly (i.e., without reclamation) as ingredients in manufacturing
processes to make new products; used directly as effective substitutes
for commercial products; or returned directly to the original process
from which they are generated as a substitute for raw material feed
stock. These exclusions do not apply to materials that are either
contained in, or used to produce fuels, however, and therefore do not
generally apply to secondary materials recycled as part of the
petroleum refining process. Petroleum industry representatives have
long argued that oil-bearing secondary materials used as ingredients in
the petroleum refining process to make fuel should be excluded from
regulation under RCRA.
Today's proposal, which deals specifically with petroleum
residuals, gives EPA the opportunity to address some larger,
longstanding issues involving where the boundaries of RCRA should be
drawn regarding jurisdiction over the petroleum industry. Therefore, in
addition to addressing specific regulatory issues that may arise as a
result of a decision to list an individual petroleum wastestream, the
Agency is proposing more comprehensive revisions to the RCRA
regulations relating to materials that are generated by and recycled
within the petroleum industry. (See Section III.E.)

C. EPA's Hazardous Waste Listing Determination Policy

Today's listing determination proposal follows the elements of the
Agency's hazardous waste listing determination policy. That policy was
presented in the dyes and pigments listing determination proposal (59
FR 66072, December 22, 1994). Readers are referred to that notice for a
description of EPA's listing policy. Also, Section III.F.2., ``Risk
Analysis,'' contains a discussion of how elements of EPA's listing
policy were applied in today's listing determination.

III. Today's Action

A. Summary of Today's Action

1. Summary of Proposed Listing Determinations
In today's notice, EPA is proposing to add three wastes generated
during petroleum refining operations to the list of hazardous wastes in
40 CFR 261.32. A summary of the waste groupings proposed for listing
are provided below with their proposed corresponding EPA Hazardous
Waste Numbers.
K170--Clarified slurry oil storage tank sediment and/or in-line
filter/separation solids from petroleum refining operations.
K171--Spent hydrotreating catalysts from petroleum refining
operations (As discussed in III.A.2 below, this listing does not
include ceramic support media.)
K172--Spent hydrorefining catalysts from petroleum refining
operations (As discussed in III.A.2 below, this listing does not
include ceramic support media.)
EPA is proposing to list certain wastes in this rule because these
materials meet the criteria set out in 40 CFR 261.11(a)(3) for listing
a waste as hazardous. EPA assessed and considered the factors contained
in these criteria primarily by incorporating them as elements in a risk
assessment. Based on this assessment, EPA is proposing to list those
wastes that pose a substantial present or potential hazard to human
health or the environment when improperly managed.
Upon promulgation of these proposed listings, all wastes meeting
the listing descriptions would become hazardous wastes and would
require treatment, storage, or disposal at RCRA Subtitle C permitted
facilities. Residuals from the treatment, storage, or disposal of the
wastes included in this proposed listing also would be classified as
hazardous wastes pursuant to the ``derived-from'' rule (40 CFR
261.3(c)(2)(I)). For example, ash or other residuals from treatment of
the listed wastes would be subject to RCRA Subtitle C hazardous

[[Page 57750]]
waste regulations. Also, 40 CFR 261.3(a)(2)(iv) (the ``mixture'' rule)
provides that, with certain limited exceptions, any mixture of a listed
waste and a solid waste is itself a RCRA hazardous waste.
However, when these materials are recycled as described in 40 CFR
261.2(e)(1)(iii) or 261.4(a)(8), they are not solid wastes and are not
subject to hazardous waste regulations. For example, if a material is
collected and returned in a closed-loop fashion to the same process, it
is not regulated. As discussed further in Section III.E of this notice,
the Agency is proposing some modifications to these recycling
exemptions.
This action also proposes not to list as hazardous eleven residuals
generated from petroleum refining operations:
Crude oil storage tank sediment.
Unleaded gasoline storage tank sediment.
Off-specification product and fines from thermal
processes.
Catalyst from reforming.
Catalyst from H2SO4 alkylation.
Sludge from H2SO4 alkylation.
HF alkylation sludge.
Spent caustic from liquid treating.
Catalyst and fines from catalytic cracking.
Catalyst from sulfur complex and H2S removal
facilities.
Sludge from sulfur complex and H2S removal
facilities.
The Agency requests comments on the proposal not to list the above
wastes. While the agency is proposing not to list crude oil storage
tank sediment, the Agency specifically requests comment on the merits
of listing this waste. Crude oil storage tank sediment could be
finalized as a listing in response to comment. The Agency also requests
comment on the data used in this proposal, the methodology and
assumptions used in the risk assessment, the waste groupings chosen by
the Agency, and other information and analyses supporting the proposed
listings.
2. Summary of Definition of Solid Waste and Other Exemptions Proposed
in Today's Notice
While the primary purpose of today's proposal is to present the
Agency's findings with respect to the hazards posed by the 14 residuals
identified in the consent decree, the Agency also conducted a parallel
effort to analyze the applicability of the definition of solid waste to
these residuals, and to identify appropriate exemptions to the proposed
listings that reflect the Agency's investigation (i.e., the appropriate
scope of the proposed listings) and that encourage responsible
recycling activities. The proposed exemptions and scope limitations are
summarized below and discussed in detail in the following sections.
a. Hazardous Petroleum Refinery Residuals Returned to Refinery
Processes. The Agency is proposing to broaden the existing exemption in
40 CFR 261.4(a)(12) for oil-bearing residuals from specified petroleum
refining sources that are inserted into the petroleum refining process.
If finalized, the existing exemption would be expanded to allow for
reinsertion of a broader array of residuals into more parts of the
refinery, including the coking process. The exemption would continue to
be limited to situations where inappropriate storage or accumulation
does not occur, and to processes that do not result in coke products
that exhibit any of the characteristics of hazardous waste. A detailed
discussion of this proposal is provided in Section III.E.
b. Use of Spent Caustics as Feedstocks. Section III.G.6 describes
the Agency's findings with respect to spent caustic from liquid
treating operations and its status as a solid waste when used as a
feedstock. A significant management practice for this residual is off-
site use as a feedstock in the manufacture of naphthenic or cresylic
acids. The Agency proposes an exclusion from the definition of solid
waste in Section III.G.6, clarifying that spent liquid treating
caustics from petroleum refineries and used as feedstock in the
manufacture of naphthenic and cresylic acid products are not solid
wastes.
c. Third Party Recycling of Spent Petroleum Catalysts. Section
III.J describes the Agency's rationale for proposing an exclusion from
the 40 CFR 266 Subpart H boiler and industrial furnace standards for
spent hydrotreating and hydrorefining catalyst recovery furnaces. Spent
hydrotreating and hydrorefining catalysts, two of the petroleum
refining residuals proposed today for listing, are frequently
regenerated for reuse or reclaimed off-site to recover nonprecious
metals such as nickel, molybdenum, cobalt, and vanadium and other
compounds sold as products (i.e., aluminum sulfate derived from the
alumina substrate material).
d. Wastewaters. The turnaround of both crude oil storage tanks and
clarified slurry oil storage tanks may result in the generation of
process wastewaters. The scope of the Agency's listing determinations
for crude oil storage tank sediment and CSO storage tank sediment and/
or in-line filter/separation solids, as described in Section III.G.1
and 2, respectively, does not include these wastewaters. These sections
also describe the limitation of the scope of the listings to sediments
generated from tanks that are directly associated with petroleum
refining operations, reflecting the Agency's lack of data regarding the
nature of sediments generated from tankage at facilities that are not
petroleum refineries.
In section III.K., the Agency proposes to exclude from the
definition of hazardous waste mixtures of crude oil storage tank
sediment (if listed) or of CSO storage tank sediment with tank
wastewaters, provided the waste waters are discharged to the oil-
recovery sewer before primary oil/water/solids separation.
e. Catalyst Support Balls. Upon removal from catalyst beds and/or
during catalyst regeneration or reclamation, spent catalysts are
separated from the support media that is used in the catalytic reactors
to optimize mixing and flow within the reactor beds. The scope of the
Agency's listing determinations for hydrotreating and hydrorefining
catalysts, as described in Section III.J, does not include these
ceramic support media.
f. Application of Existing Exemptions to the Residuals of Concern.
Section III.G.5 describes EPA's findings with respect to spent sulfuric
acid used as a catalyst in refinery alkylation processes. The Agency
concluded that this residual is already managed in a way that is
virtually exempt from the definition of solid waste under 40 CFR
261.4(a)(7).

B. Description of the Industry

Petroleum refineries are defined as ``establishments primarily
engaged in the production of gasoline, distillate fuel oils, residual
fuel oils, naphtha, liquefied refinery gases, and lubricants through
the integration of fractionation and/or straight distillation of crude
oil, re-distillation of unfinished petroleum derivatives, cracking, or
other processes'' (Office of Management and Budget, 1987).
The refineries use a complex combination of interdependent
operations to produce these petroleum-derived products. Depending upon
the type of crude being processed, the type of product to be produced,
and the process units present at a refinery, various combinations of
processes may be employed to effect the separation of crude fractions.
Petroleum refining operations and processes include desalting of crude,
atmospheric and vacuum distillation, hydrotreating, catalytic cracking,
thermal processing and upgrading of residual fuel oil, light

[[Page 57751]]
hydrocarbon processing, hydrocracking, catalytic reforming, alkylation,
extraction, isomerization, processing of lubricating oil, removal of
sulfur, and blending of products. Additional processes may also be
employed to produce additives or other desired products.
Today's proposal is based on the Agency's analysis of data
characterizing the industry in 1992. In 1992, 185 operating refineries
were reported by the U.S. Department of Energy's Petroleum Supply
Annual, with a total distillation capacity of 15 million barrels of
crude oil per calendar day.

C. Overview of EPA's Information Collection Activities

OSW's listing determination for the petroleum refining industry has
been underway since 1992 and can be characterized in terms of two major
avenues for information collection: field work and survey evaluation.
1. Field Investigations and Sampling
As part of the Agency's field work, engineering site visits,
familiarization sampling, and record sampling were conducted. Twenty-
five refineries were randomly selected for evaluation in the field
program. The industry was stratified into large and small refineries
and the 25 refineries were selected randomly (and proportionately) from
the two strata so that any differences in waste generation and
management practices could be observed. Engineering site visits were
conducted at each of the targeted refineries, at which time the Agency
conducted extensive discussions with the facilities and representatives
of the American Petroleum Institute (API) to certify each of the
potential sampling locations would result in samples that were
representative of normal operating conditions and typical industry
practices.
Sixty three record samples of the listing residuals of concern were
collected and analyzed. All sample volumes were obtained in duplicate
for the purpose of providing API with sample splits. Of the 63 samples
collected, 46 were split directly with API; the remaining 17 were
either split with the refinery (12 samples) or only collected as single
EPA aliquot (5 samples). Of the 46 split samples, the analytical data
for 31 were compared directly to the API data. The results of the
comparison indicated good agreement. The sampling and analysis plans
and analytical data reports that are not Confidential Business
Information (CBI) are available in the docket for this rule (see
ADDRESSES section), and provide detailed discussions regarding the
identification and collection of samples. The Listing Background
Document available in the docket provides additional information on the
Agency's field program, including a more detailed discussion of EPA's
site selection process.
EPA's approach to sample analysis is described generally in its
Quality Assurance Project Plan (QAPjP), dated October 21, 1992
(describing the familiarization phase of this investigation) and
September 22, 1993 (describing the record sampling phase of this
investigation) available in the docket of today's rule. Target analytes
were identified by compiling lists of target constituents used in
previous OSW investigations, including the petroleum refining listing
investigation conducted in the 1980s, the 1984 ``Skinner List''
(guidance issued by OSW for the characterization of wastes derived from
petroleum refinery wastewater treatment sludge), and the Delisting
Program. Additional constituents were added to reflect waste-specific
concerns such as amines from sulfur-removal residuals, and fluorides
from HF alkylation residuals. The Agency's contracted laboratory
confirmed its ability to reliably and adequately quantify the target
analytes during the analysis of six familiarization samples collected
during the engineering site visits. Upon completion of the
familiarization sample analysis effort, EPA finalized the target
analyte list and QAPjP with a list of more than 180 target
constituents. In addition, during both familiarization and record
sampling and analysis, the Agency quantified the ten most abundant
nontarget volatile and the 20 most abundant nontarget semi-volatile
organics in each sample.
The Agency believes that the samples collected and analyzed under
its field investigations are generally representative of residuals
typically generated throughout the industry. This belief is based on
(1) the extensive discussions between the Agency, the targeted
facilities and API regarding the sampling protocol and sample
representativeness; (2) the Agency's broader understanding of the
residuals and the industry's array of management practices developed
during extensive review of the industry-wide survey (described below);
and (3) the fact that the toxicants that ultimately were found through
risk assessment modeling to show significant risk and serve as the
proposed basis for listing in today's notice are all common refinery
constituents of concern (e.g., benzene, arsenic, polynuclear aromatic
hydrocarbons (PAHs)) that are found in virtually all crudes and thus
reasonably are expected to be present in refinery residuals across the
Nation.
2. RCRA Section 3007 Survey
The survey effort included the development, distribution, and
assessment of an extensive industry-wide section 3007 survey. The
questionnaire covered topics such as crude oil and product information,
facility and unit process flow diagrams, process descriptions, residual
generation and management profiles, residual and contaminated soil and
debris characterization, residual management unit and media
characterization, general facility characterization (focussing on
exposure pathway characterization), source reduction efforts, and
certification.
The survey was distributed in September 1993 to all refineries
identified as active in 1992 in the DOE Petroleum Supply Annual. Of the
185 surveys distributed, completed responses were obtained for 172
refineries. The remaining refineries notified EPA that they had stopped
operations at some point in or after 1992 and thus were unable to
complete the survey.
The Agency entered the completed surveys into a relational database
known as the 1992 Petroleum Refining Database (PRDB). An exhaustive
engineering review of each facility's response was then conducted,
resulting in follow-up letters to most of the industry which sought
clarifications, corrections, and additional data where needed. The
responses to the follow-up letters were entered into the database. A
wide variety of additional quality assurance checks were run on the
data, with added emphasis on the listing residuals, to ensure that the
residuals of concern were characterized as completely and accurately as
possible. Follow-up telephone interviews were conducted as necessary to
address remaining data issues. After extensive review, the Agency
believes that the data are reliable and represent the industry's
current residual generation and management practices.

D. Description of the Process Residuals in Comparison With the Consent
Decree Language

The consent decree identifies fourteen residuals for which the
Agency must make proposed listing determinations in this rulemaking.
Upon investigation of the categories identified in the consent decree,
the Agency determined that several of the categories should be split
into distinct subcategories to allow the

[[Page 57752]]
Agency to differentiate between unique residuals. For example, the
consent decree identified as one residual catalysts from sulfur complex
and H2S removal facilities. There are two major subcategories of
catalysts used in refinery sulfur removal facilities: Claus catalysts
(an alumina bauxite catalyst) and tail gas treating catalysts
(typically a cobalt/molybdenum catalyst). These wastes are inherently
different in their composition, application, and management, and thus
were assessed separately in the Agency's risk assessment.
Table III-1 identifies the residuals in the consent decree,
describes their coverage in the listing determinations proposed in
today's rulemaking, and the action proposed.

Table III-1.--Consent Degree Residuals
----------------------------------------------------------------------------------------------------------------
Residuals identified in the consent decree Coverage in today's rulemaking
----------------------------------------------------------------------------------------------------------------
Crude oil storage tank sludge.......................... Crude oil storage tank sediment.
Unleaded storage tank sludge........................... Unleaded gasoline storage tank sediment.
Clarified slurry oil sludge from catalytic cracking.... Clarified slurry oil (CSO) storage tank sediment and/or
in-line filter/separation solids.
Catalyst from catalytic hydrotreating.................. Non-precious metal hydrotreating catalysts.
Catalyst and fines from catalytic cracking............. Equilibrium catalysts and catalyst fines were evaluated
as individual subcategories based on differences in
particle sizes and management practices.
Catalyst from catalytic hydrorefining.................. Non-precious metal hydrorefining catalysts.
Catalyst from catalytic reforming...................... Includes spent catalysts and fines.
Catalyst from H2SO4 alkylation......................... Spent sulfuric acid.
Sludge from H2SO4 alkylation........................... Same.
Sludge from HF alkylation.............................. Neutralization sludges.
Off-spec product and fines from thermal processes...... Same.
Spent caustic from liquid treating..................... Same.
Process sludge from sulfur complex and H2S removal Sludges from amine-based sulfur removal systems,
facilities. including turnaround sludges and filter cartridges.
Catalyst from sulfur complex and H2S removal facilities Claus catalyst, an alumina-based sulfur conversion
catalyst.
SCOT-like catalyst, a cobalt/molybdenum
tailgas treating catalyst.
----------------------------------------------------------------------------------------------------------------

E. Hazardous Oil-Bearing Residuals Returned to Refinery Processes

EPA is today proposing to exclude from the definition of solid
waste oil-bearing residuals from specified petroleum industry sources
that are inserted into the petroleum refining process (including the
petroleum coker) along with normal process streams, if these materials
are not stored in a manner involving placement on the land, or
accumulated speculatively before being so recycled, and if the
resulting coke product does not exhibit one or more of the
characteristics of hazardous waste.
1. Background
a. January 8, 1988 Proposal. On January 8, 1988, EPA proposed rules
to implement a decision by the District of Columbia Circuit Court
regarding EPA's statutory authority to regulate recycled materials. See
53 FR 519, January 8, 1988. In its decision in American Mining Congress
v. EPA, 824 F. 2d1177 (D.C. Cir. 1987) (AMC I), the D.C. Circuit Court
held that EPA's rules defining the statutory term ``solid waste'' (RCRA
Section 1004(27)) exceeded the Agency's statutory authority to the
extent that the rules asserted jurisdiction over ``materials that are
recycled and reused in an ongoing manufacturing or industrial
process.'' Id. at 1186 (emphasis original). The court held that
``Because these materials have not yet become part of the waste
disposal problem,'' Id., they are not yet ``discarded'' within the
meaning of Section 1004(27) and so cannot be considered to be ``solid
wastes.''
In its January 1988 proposal, EPA responded to the AMC I decision
specifically as it applied to petroleum refining industry operations.
The Agency proposed to exclude from the regulatory definition of solid
waste oil bearing petroleum residuals that are returned for further
refining ``as part of one continuous and ongoing process.'' (53 FR 525,
January 8, 1988.) More specifically, EPA proposed to exclude oil-
bearing residues from the refining process when those residues are
generated on-site and reinserted on-site into the petroleum refining
process (including the coker), provided that the residues were not
speculatively accumulated or stored in a manner involving land
placement.
Subsequent decisions have established that the decision in AMC I is
relatively narrow. In particular, courts have rejected the argument
that ``potential reuse of a material prevents the Agency from
classifying it as 'discarded'.'' American Mining Congress v. EPA, 907
F. 2d 1179, 1186 (D.C. Cir. 1990) (AMC II). The proper test as to when,
as a matter of law, the Agency is foreclosed from classifying a
material as a solid waste is when a material is ``destined for
immediate reuse in another phase of the industry's ongoing production
process'' and that ``have not yet become part of the waste disposal
problem.'' Id. at 1186. EPA retains considerable discretion in
ascertaining how to apply this standard. For example, secondary
materials generated by one industry and sent to another industry for
reclamation could be classified as solid wastes (although EPA retains
discretion as to whether to make that determination). (American
Petroleum Inst. v. EPA, 906 F. 2d 726, 740-41 (D.C. Cir. 1990); Ilco v.
EPA, 996 F. 2d 1126 (11th Cir. (1993); Owen Electric Steel v. Browner,
37 F. 3d 146 (4th Cir. 1994)). So can secondary materials generated on-
site, stored in wastewater treatment impoundments, and reclaimed within
the process which generated them. AMC II. EPA also must normally
justify determinations that a secondary material being recycled is not
a solid waste by showing how the determination is consistent with
RCRA's objective to ``establish a cradle-to-grave regulatory structure
for the safe handling of hazardous wastes.'' API, 906 F. 2d at 741.
b. July 28, 1994 Final Recovered Oil Rule. On July 28, 1994, EPA
finalized parts of the January 8, 1988 proposal pertaining to petroleum
refining industry operations. The proposal was based on the Court's
decision in AMC I. As noted, however, post-AMC I decisions make clear
that the statute

[[Page 57753]]
affords EPA great latitude to set the jurisdictional parameters of
RCRA. As a consequence, the final exclusion is more narrow than the one
proposed: it excludes a more limited set of materials, and imposes
greater restrictions on where the materials can be inserted within the
petroleum refining process.
In its January 1988 proposal, EPA did not distinguish between
recovered oil and oil-bearing hazardous sludges, nor did it distinguish
between the petroleum coker and other petroleum process units in
defining the scope of the proposed petroleum refining exclusion. In
contrast, in the July 28, 1994 rule, EPA limited the exclusion to
recovered oil from petroleum refining, exploration and production that
are inserted into the petroleum refining process prior to distillation
and catalytic cracking. Also, the final exclusion thus does not apply
to recovered oil reinserted into the petroleum coker.
(Sec. 261.4(a)(12)).
(1) Definition of Recovered Oil. Recovered oil, as defined in
Sec. 261.4(a)(12), includes materials that are primarily oil and that
are recovered from any phase of petroleum exploration, refining,
production, and transportation. As explained in the July 28, 1994 rule,
EPA limited the exclusion to recovered oil because recovered oil is
equivalent to the raw materials normally used in the petroleum refining
process in its composition and management.
The exclusion does not apply to hazardous oil-bearing sludges. EPA
reasoned that these materials are typically unlike raw materials
normally used in the petroleum refining process (i.e., crude oil).
First, oil-bearing sludges are not normally composed primarily of oil.
Additionally, the units in which they are managed (e.g., API
separators, DAF units, land treatment units and surface impoundments)
are not parts of the refining process, but instead function as waste
holding and treatment units. Finally, EPA cited damage incidents
associated with management of such materials as confirmation that these
materials can be part of the waste disposal problem.
(2) Limitation on Point of Insertion. The final recovered oil
exclusion does not apply to recovered oil or other hazardous oil-
bearing secondary materials that are inserted into the petroleum coker.
EPA decided not to exclude materials that are recycled in the petroleum
coker because of concerns about the fate of the hazardous constituents
that may be contained in the recovered oil. As stated in the preamble
to the recovered oil rule, the Agency was concerned that toxic
constituents could end up in the coke product in quantities that could
be harmful to human health and the environment when the coke is burned
as a fuel. See 59 FR 38542, July 28, 1994. EPA had limited data on the
composition of hazardous oil-bearing residuals compared to normal coker
feed and was concerned that additional toxic constituents (e.g., heavy
metals) that may be present in these secondary materials could be
discarded by simple incorporation into the coke product, in which case
the coke could be part of the waste disposal problem when burned.
The Agency therefore retained jurisdiction over recovered oil, and
other hazardous oil-bearing secondary materials that are inserted into
the petroleum coker. Cokers that receive hazardous oil-bearing waste as
a feedstock are currently not subject to regulation under RCRA,
however. (59 FR 38542, July 28, 1994.) (See also May 3, 1995 letter to
Ralph J. Colleli, API Counsel, from Michael Shapiro, Director, Office
of Solid Waste).
2. Proposed Amendments To Address Hazardous Residuals Returned to the
Refining Process
a. Summary of Proposed Amendments. In the preamble to the final
recovered oil rule, EPA indicated that the rulemaking was not
necessarily its final disposition of jurisdictional issues relating to
the petroleum industry, and that further exclusions might be warranted
after additional study (59 FR 38536, and 38541, July 28, 1994). Since
promulgation of the recovered oil rule, EPA has received numerous
comments from petroleum industry representatives objecting to the
Agency's decision to narrow the scope of the originally proposed
exclusion. Industry representatives continue to assert that cokers are
an integral part of the petroleum refining process and that the
practice of recycling oil-bearing secondary materials (including
recovered oil) as feed to petroleum cokers, or elsewhere to the
refining process, falls outside of RCRA jurisdiction. In light of these
comments, and as part of its continued efforts to define more clearly
the scope of RCRA jurisdiction within the petroleum industry, EPA has
reviewed its position regarding whether exclusions should apply only to
recovered oil and whether reinsertion into petroleum cokers as well as
earlier parts of the refining process should be excluded.
Accordingly, the Agency has reevaluated existing information on
oil-bearing residuals and their use in the petroleum refining process.
In particular, EPA has reviewed existing information on the composition
of oil-bearing refinery residuals and the fate of toxic constituents
contained in secondary materials that are reinserted into the coker. In
addition, the Agency has obtained more detailed information from the
petroleum refining industry on the coking process itself. The Agency's
analysis, which is discussed in detail below, supports broadening the
existing recovered oil exclusion. Therefore, EPA is today proposing to
expand the recovered oil exclusion to cover all oil-bearing secondary
materials that are generated within the petroleum refining industry and
are reinserted into the petroleum refining process (including
distillation, catalytic cracking, fractionation, or thermal cracking
(i.e., coking)).
Under today's proposal, Sec. 261.4(a)(12) would be revised to
provide that oil-bearing residuals from specified petroleum industry
sources that are inserted into the petroleum refining process
(including the coker) along with normal process streams would be
excluded from the definition of solid waste, if the material is not
stored in a manner involving placement on the land, or accumulated
speculatively before being recycled and (if insertion is into the
coker) if the coke product does not exceed characteristically hazardous
levels. More specifically, today's proposed exclusion would cover oil-
bearing secondary materials that are generated on-site at refineries,
transported intracompany from off-site, or received from any off-site
facilities (intercompany transfers) in the following SIC codes: 1311,
1321, 1381, 1382, 1389 (oil and gas extraction), 2911 (petroleum
refining), 4612 and 4613 (crude oil and refined petroleum pipelines),
4922 and 4923 (natural gas transmission and distribution), 4789
(independent pipeline operators), and 5171 and 5172 (petroleum product
bulk stations and terminals). It should be noted that certain existing
exclusions provided under Sec. 261.6 that pertain specifically to
petroleum refining wastes would become unnecessary as a result of
today's proposal. The Agency will amend these provisions as necessary
in its final rulemaking.
Today's proposal would not effect the current regulatory status of
petroleum refinery wastewaters. EPA considers refinery wastewaters to
be discarded materials and therefore solid wastes potentially subject
to regulation under RCRA (59 FR 38539, July 28, 1994). Likewise,
wastewater treatment systems in which RCRA hazardous wastes are managed
would continue to be subject to regulation as hazardous waste
management units or exempt under 40 CFR 264.1 under today's proposal.

[[Page 57754]]

Today's proposed exclusion would also be expanded to include
recovered oil that is generated from certain organic chemical industry
operations and inserted into a petroleum refining process along with
normal process streams.
b. Rationale for Proposed Amendments. (1) Exclusion for Oil-Bearing
Residuals Returned to Refining Process. Today's proposed exclusion
applies to any oil-bearing residual material from any phase of
petroleum exploration, refining, transport or marketing that is
inserted directly into any part of the refining process. These
materials are most likely to be inserted into the petroleum coker, and
the basis for this proposed exclusion is discussed at length below.
Materials inserted elsewhere into the refining process are likely to
already be recovered oil, and hence to be excluded, or to so closely
resemble recovered oil as to fit the rationale of the existing rule, if
not its exact literal language. Thus, with respect to insertion into
parts of the refining process other than coking, extending the
exclusion to all oil-bearing materials largely avoids unproductive
disputes about what is and is not recovered oil, and leaves refineries
with maximum flexibility as to the best part of the process to reinsert
oil-rich residuals.
(2) Proposed Exclusion for Oil-Bearing Materials Inserted into
Petroleum Coking. Role of the Petroleum Coker in the Petroleum Refining
Process. EPA decided in the July 1994 rule not to exclude hazardous
oil-bearing secondary materials that are inserted into the coking
process until the Agency studied further whether the coker may be
functioning, at least in part, as a waste management unit in these
cases (59 FR 38542, July 28, 1994). A more detailed review of the
coking process has since convinced EPA that the coker is in fact an
integral part of the petroleum refining process and is similar to other
refining processes such as distillation and catalytic cracking. The
coker is normally located on-site and typically processes oil-bearing
materials that are generated on-site. The petroleum coker contributes
significant revenue to the refinery primarily through upgrading of
lower value hydrocarbons into light ends that are used to produce more
valuable product fuels. While coke is a co-product of the coking
process, the primary purpose of the coker is, in fact, to thermally
convert longer-chain hydrocarbons to recover the more valuable middle
and light end hydrocarbons that are used to produce high grade fuels
(e.g., gasoline, kerosene, jet fuel, etc.). The typical coker yield is
about 25%-30% petroleum coke and 70% light hydrocarbons that are
returned to the refining process to produce high grade fuels. The
importance of the coker to the refining process is illustrated by the
fact that the coking operation may determine the economic viability of
the refinery. Given that the coker is a crucial unit in the refining
process, industry representatives assert and the Agency believes that
it is highly unlikely that refinery owners or operators would allow any
incompatible materials to be inserted into the coker for fear of
interfering with proper operation of the coker. It is also significant
that, consistent with EPA's finding that cokers are considered process
units for purposes of today's proposed exclusion, cokers are also
viewed as process units under recently issued Clean Air Act (CAA)
regulations and that emissions from cokers are subject to regulations
under the National Emission Standards for Hazardous Air Pollutants from
Petroleum Refineries (40 CFR 63 Subpart CC; 60 FR 43244, August 18,
1995).
Hazardous Oil-bearing Residuals Compared to Normal Coker Feed. EPA
also initially decided not to exclude recovered oil and other oil-
bearing hazardous materials used to produce petroleum coke because of
concerns that toxic metals contained in these materials are being
disposed of by incorporation into a coke product. At the time the
recovered oil rule was published, the Agency had only limited data
indicating that oil-bearing hazardous residuals do not contain
significantly different amounts of toxic constituents from the heavy
petroleum residuals that are normally fed to the petroleum coker, but
was uncertain of the representativeness of the information. The Agency
has since received some additional data on the composition of oil-
bearing hazardous sludges relative to crude oil residuals that are
typically fed to the coker which supports industry's claim that oil-
bearing sludges generated during the refining process are substantially
similar to normal coker feedstock material.2 At this time, all of
the data in EPA's possession indicates that the recycling of oil-
bearing residuals can be accomplished without raising hazardous
constituent (e.g., heavy metal) concentrations to levels of concern in
the final coke product. To guard against this possibility, the Agency
is limiting this exclusion to the production of coke which does not
exhibit the characteristics of a hazardous waste. This is consistent
with the thrust of RCRA Sec. 3004(q)(2)(A) which subjects certain
petroleum refinery wastes converted into petroleum coke to regulation
if the resulting coke exhibits a characteristic.

\2\ See October 8, 1993 and October 13, 1993 letters from Mark
A. Smith (Unocal) to James R. Berlow.
---------------------------------------------------------------------------

Another significant consideration bearing on today's proposal is
the fact that hazardous oil-bearing sludges constitute only a very
small fraction of the total residual materials that are generated by
the petroleum refining process and inserted back into the refinery for
further processing. Due to process limitations, hazardous oil-bearing
materials comprise only about 1-3% of the total amount of refining
residuals that are routinely fed to the coker according to industry
representatives.
Additionally, EPA has found that hazardous oil-bearing refinery
sludges are managed in much the same way as are non-regulated crude oil
residuals prior to insertion into the petroleum coker. In a typical
petroleum refinery operation, refinery residuals (e.g., K048-52) that
are inserted into petroleum cokers are transferred from wastewater
treatment tanks to the coker via a closed system. The wastewater
treatment tanks in which the residuals are initially stored are exempt
from Subtitle C regulation. (See 40 CFR 264.1(g)(6).) The residuals are
typically transferred from exempt wastewater treatment tanks via hard
pipe or tank trucks to stationary tanks or containers where oil is
recovered and/or the secondary materials are prepared for insertion
into the coker. Since the residuals are not ordinarily stored in stand
alone storage tanks but are instead transferred directly to process
tanks and containers (i.e., centrifuge systems, desorption units, etc.)
EPA does not believe that storage of the residuals prior to reinsertion
into the refining process poses hazards to human health or environment.
In addition, American National Standard Institute (ANSI) standards
governing design, construction, operation, maintenance and inspection
of petroleum terminal and tank facilities help to ensure
environmentally protective management storage of the in-process
residuals prior to reinsertion into the coker or other parts of the
refinery.
Furthermore, data on the composition of the coke product indicate
that use of oil-bearing secondary materials has little, if any, impact
on the quality and/or properties of the resulting coke. In particular,
EPA has information which indicates that levels of toxic metals in coke
produced from oil-bearing sludges are comparable to those found in coke

[[Page 57755]]
produced strictly from crude oil residuum.3

\3\ See February 2, 1993 data submission from Mobil Oil
Corporation.
---------------------------------------------------------------------------

Finally, coke product is subject both to regulatory requirements
and certain limited industry product specifications, a fact that serves
to ensure the quality of the coke product. The statute and existing
regulations provide that coke product derived from a hazardous waste
which exhibits a hazardous characteristic (as determined by application
of the Toxicity Characteristic Leaching Procedure) is subject to
regulation as hazardous waste under RCRA. See RCRA Sec. 3004(q)(2)(A)
and 40 CFR 261.6(a)(3)(vii). EPA would retain this provision under
today's proposal as a means of ensuring that reinsertion of these
materials is not part of the waste disposal problem. See generally AMC
II, supra. Coke is also subject to product standards established by the
American Society for Testing of Materials' (ASTM) for volatile matter
and ash content. Taken together, these controls help to ensure that
coke product does not contain unsafe levels of toxic contaminants.
Restrictions on Land Placement and Speculative Accumulation.
Today's proposed exclusions do not apply to oil-bearing hazardous
secondary materials that are placed in land-based hazardous waste
management units such as surface impoundments or land treatment units.
The Agency considers materials placed in such units to be discarded,
and hence solid wastes. Land-based units that contain hazardous oil-
bearing residuals would remain subject to Subtitle C requirements under
today's proposal. AMC II, 907 F. 2d at 1186-87. In addition, any
material that spills from tanks and containers and is not expeditiously
retrieved for reinsertion is a solid waste and, if listed or
characteristic, a hazardous waste. See Sec. 261.33(d) and 55 FR 22671,
June 1, 1990.
Today's proposed exclusion also does not apply to oil-bearing
secondary materials that are accumulated speculatively (as defined in
Sec. 261.1(c)(8)) before being recycled into a petroleum refining
process. Under RCRA, secondary materials that are accumulated
speculatively are considered to be discarded and hence solid waste. EPA
applies this standard condition to otherwise excluded secondary
materials to prevent risks from prolonged storage of the material
before recycling. See 50 FR 634-635, 658-661, Jan. 4, 1985.
Restrictions on Petroleum Coke Produced From Hazardous Oil-Bearing
Secondary Materials. Under the current regulations, petroleum coke
produced from hazardous oil-bearing refinery wastes is excluded from
regulation under RCRA provided that the resulting coke product does not
exceed one or more of the characteristics of hazardous waste in part
261, Subpart C (Sec. 261.6(a)(3)(vii)). Under today's proposal, EPA
would continue to regulate coke that exhibits a characteristic as
hazardous if the coke is produced from oil-bearing residuals that are
excluded from regulation because they are reinserted into the refining
process, but are otherwise regulated as hazardous waste. In addition,
EPA is proposing to condition the exclusion for oil-bearing residuals
that are inserted into the coker on the requirement that coke produced
from these materials not exceed characteristic levels. In other words,
the exclusion would not apply to secondary materials that, if recycled,
would result in coke that exhibits a characteristic. To do otherwise,
as noted, would lead to situations where management of oil-bearing
residues becomes part of the waste management problem by tainting the
coke. EPA thus is proposing these conditions to ensure that coke
produced from otherwise excluded oil-bearing secondary materials will
not contain toxic constituents in quantities that could be harmful to
human health and the environment when the coke is burned so as to
assure that the proposed exclusion does not undermine RCRA's cradle-to-
grave purpose. API, 906 F.2d at 741; RCRA Sec. 3004(q)(2)(A). EPA
requests comment on the adequacy of the TCLP for this purpose.
Materials That Are Deemed To Be Inherently Waste-Like. The existing
regulations provide EPA with authority to designate as solid wastes
materials that are inherently waste-like regardless of the mode of
recycling. (See Sec. 261.2(d).) Under current regulations, the Agency
may designate materials as inherently waste-like either because they
are typically disposed of or incinerated on an industry-wide basis or
they contain toxic constituents not normally found in the raw materials
or products for which they are being substituted (50 FR 637, January 4,
1985). Therefore, while EPA is proposing to generally exclude hazardous
oil-bearing refinery residuals that are returned to the petroleum
refining process, the Agency retains the authority to regulate specific
waste-streams as ``inherently waste-like'' if it finds that particular
petroleum refining residuals contain high levels of toxic constituents
that are not ordinarily found in the normal coker feed and do not
contribute to the product.
Regulatory Status of Petroleum Refinery Wastewater and Wastewater
Treatment Operations. Under today's proposal petroleum refining
wastewaters would continue to be subject to regulation as solid wastes
under RCRA. Petroleum industry representatives have argued in public
comments submitted in response to both the January 8, 1988 proposal and
the July 28, 1994 final recovered oil rule, that plant wastewaters
containing oil are not solid wastes. Industry representatives contend
that primary wastewater treatment operations in which oil is skimmed
and oil-bearing sludges are separated from plant waters are part of the
ongoing refining process.
EPA has considered this argument but does not agree for the
following reasons. First, petroleum refining wastewaters differ from
both recovered oil and oily sludges that are separated from the
wastewaters in that, unlike these secondary materials, the wastewaters
themselves are not analogous in composition to normal petroleum
refining feedstock material and consequently are not reinserted into
the petroleum refining process to produce petroleum products. Instead,
petroleum refining wastewaters from which oily materials have been
removed are discharged, and are thus not eligible for exclusion as a
petroleum refining process feed.
Second, as explained in the preamble to the recovered oil rule,
primary wastewater treatment operations exist to treat plant
wastewater. The main purpose of wastewater treatment is to purify
discarded wastewaters from the refining process so that they can
ultimately be discharged pursuant to Clean Water Act requirements, not
to recover secondary materials for recycling back into an ongoing
manufacturing or industrial process. See 59 FR 38539, July 28, 1994.
A final and equally important consideration in EPA's decision not
to exclude refinery wastewaters from regulation is that regulation of
these wastewaters ensures treatment of hazardous constituents in
characteristic wastestreams that are managed in wastewater treatment
impoundments (e.g., impoundments in which biological treatment occurs)
in accordance with the land disposal restriction (LDR) requirements of
Part 268. See 59 FR 38540.
Recovered Oil From Co-Located Petroleum Refineries and
Petrochemical Facilities. EPA is also today proposing to add an
exclusion at Sec. 261.12(a)(13) for recovered oil that is generated by
certain

[[Page 57756]]
organic chemical industry operations and inserted into petroleum
refining processes provided that the conditions discussed above are met
(i.e., provided that the recovered oil is not stored in a manner
involving placement on the land, or accumulated speculatively before
being recycled and that (if insertion is into the coker) coke product
does not exceed characteristically hazardous levels).
The final recovered oil exclusion does not currently apply to
recovered oil from organic chemical industry operations except in cases
where petrochemical and petroleum refining operations share a common
wastewater treatment system (where wastewater from petrochemical
processing units typically comprises only small percentage of the total
refinery wastewater volume). In these cases, given the predominance of
petroleum refining wastewater, the Agency believes that the recovered
oil exclusion appropriately applies to oil recovered from shared
petrochemical/petroleum refining wastewater treatment systems.4
The Agency did not more broadly exclude recovered oil from organic
chemical operations in its final recovered oil rule because of concerns
about additional toxic constituents that may be present in oil
recovered from petrochemical processing residuals (i.e., the exclusion
is provided on the premise that the oil-rich materials in question
contain the same constituents as normal refining process streams).

\4\ May 3, 1995 letter from Michael Shapiro (EPA) to Ralph J.
Colleli, Jr. (API).
---------------------------------------------------------------------------

EPA is aware, however, that some petrochemical facilities recover
oil separately from their process streams and send it to petroleum
refineries for insertion into the refining process. This practice
typically occurs between petroleum refineries and chemical operations
that are either co-located or owned by the same company. The oil
recovered from petrochemical operations typically comes from ``dry''
process streams, i.e., hydrocarbon streams with little or no water
content that are recovered outside of wastewater treatment systems. It
is generally composed of hydrocarbons that originate from, or are
derived from, feedstocks supplied by the petroleum industry.
Since promulgation of the final recovered oil rule in July 1994,
the Agency has received compelling information from the chemical
manufacturing industry indicating that the recovered oil from these
organic chemical industry operations is comparable to oil recovered
from petroleum refining operations.5 Based on this information,
which is described in detail below, the Agency is proposing to exclude
oil that is recovered from petrochemical operations and inserted into
co-located or commonly owned petroleum refining operations.

\5\ September 13, 1995 letter to Becky Daiss (Office of Solid
Waste) from Michael W. Steinberg (Morgan, Lewis & Bockius and July
31, 1995 letter to Steven E. Silverman (U.S. EPA, Office of General
Counsel) from Michael W. Steinberg (Morgan, Lewis & Bockius).
---------------------------------------------------------------------------

The specific reasons for the proposed petrochemical exclusion are
as follows. First, chemical industry representatives have argued and
EPA agrees that the need to closely control petroleum product quality
makes it unlikely that the recovered oil from the dry organic chemical
plant streams covered by the proposed exclusion would contain toxic
contaminants not otherwise found in petroleum feedstock. The presence
of non-hydrocarbon contaminants in the recovered oil can jeopardize the
integrity of the refined product. Product quality problems (e.g.,
solids or potential gum-forming problems in automobile fuel injection
or carburetor systems) can, in turn, have a widespread impact both on
customers and the refiners because of the extensive distribution
network in the industry. In addition, quality of the recovered oil
feedstock is important to the integrity of the refining process itself
(e.g., some chemicals and metals can cause equipment fouling and costly
downtime at refineries).
Precautions are therefore taken to ensure that recovered oil from
petrochemical plants does not contain contaminants that may adversely
affect the quality of refinery products or cause equipment and catalyst
fouling process unit downtime within refineries. Recovered oil from
organic chemical operations is segregated from other by-product or
waste streams generated by petrochemical plants. In addition, the
petrochemical recovered oil streams, which are generally aggregated on-
site, are routinely analyzed before being sent to the petroleum
refinery for use as a feedstock to ensure that the recovered oil does
not include toxic contaminants beyond those found in normal petroleum
refining process streams. Recovered oil quality parameters include bulk
solids and water content, bromine number (an indicator of olefin
content and potential fouling due to polymerization) and specific
gravity.
Second, the Agency has received sampling and analytical data that
supports industry's premise that recovered oil from petrochemical and
petroleum refining operations is similar in composition and that,
consequently, petrochemical recovered oil is suitable for insertion
into the petroleum refining process. The data provides a comparison
between recovered oil samples from co-owned petrochemical and petroleum
refining operations on key parameters including specific gravity,
distillation temperature ranges, flash point, hydrocarbon type, and
sulfur, ash, and total chlorine content. The analysis indicates that
the petrochemical recovered oil is comprised essentially of
hydrocarbons that are within a refinery's distillation range and
hydrocarbon type. The refinery and chemical plant recovered oil samples
were also compared against the Agency's used oil fuel specification.
The used oil specification includes levels for arsenic, cadmium,
chromium, lead, and flash point. Used oil that is within the specified
limits is considered by EPA to be comparable to crude oil for
regulatory purposes. The analysis of all recovered oil samples
indicates that arsenic, cadmium, chromium, lead and total halogen
levels are well below the used oil fuel specification. The
petrochemical recovered oil samples were below detection limits for the
specified contaminants. Flash points of both types of recovered oil
were also well below the used oil specification minimum.
EPA requests comment on today's proposed exclusion for recovered
oil that is generated by organic chemical plants and inserted into co-
located or commonly owned petroleum refining processes along with
normal refining process streams. Today's proposal is based on a very
limited set of data. To ensure that the data are representative of the
industry, the Agency is soliciting additional data on the composition
of recovered oil from petrochemical operations that is typically sent
to petroleum refineries. Additionally, EPA may consider broadening the
proposed exclusion to include recovered oil from plastic materials and
resins manufacturers (SIC Code 2821), synthetic rubber manufacturers
(SIC Code 2822), and cyclic crude and intermediate producers (SIC Code
2865) if the Agency receives sufficient analytical data to support such
an extension. Finally, EPA also solicits additional information on
refinery limitations that serve to preclude introduction of toxic
constituents from recovered oil from chemical manufacturing operations.

F. Description of Health and Risk Assessments

In determining whether wastes generated from petroleum refining

[[Page 57757]]
operations meet the criteria for listing a waste as hazardous as set
out at 40 CFR 261.11, the Agency evaluated the potential toxicity and
intrinsic hazard of constituents present in the wastes, the fate and
mobility of these chemicals, the likely exposure routes, and the
current waste management practices. A quantitative risk assessment was
conducted for those wastes where the available information made such an
assessment possible.
1. Human Health Criteria and Effects
The Agency uses health-based levels, or HBLs, as a means for
evaluating the level of concern of toxic constituents in various media.
In the development of HBLs, EPA first must determine exposure levels
that are protective of human health and the environment, then apply
standard exposure assumptions to develop media-specific levels. EPA
uses the following hierarchy for evaluating human health effects data
and health-based standards in establishing chemical specific HBLs:
The Maximum Contaminant Level (MCL) is used as the HBL for
the ingestion of the constituent in water, when it exists. MCLs are
promulgated under the Safe Drinking Water Act (SDWA) of 1974, as
amended in 1986, and consider technology and economic feasibility as
well as health effects.
Agency-verified Reference Doses (RfDs) or Reference
Concentrations (RfCs) are used in calculating HBLs for noncarcinogens
and verified carcinogenic slope factors (CSFs) in calculating HBLs for
carcinogens. Agency-verified RfDs, RfCs, and CSFs and the bases for
these values are presented in the EPA's Integrated Risk Information
System (IRIS).
RfDs, RfCs, or CSFs are used which are calculated by
standard methods but not verified by the Agency. These values can be
found in a number of different types of Agency documents and EPA used
the following hierarchy when reviewing these documents: Health Effects
Assessment Tables (HEAST); Human Health Assessment Group for
Carcinogens; Health Assessment Summaries (HEAs) and Health and
Environmental Effects Profiles (HEEPs); and Health and Environmental
Effects Documents (HEEDs).
Use RfDs or CSFs that are calculated by alternative
methods, such as surrogate analyses, including structure activity
analysis, and toxicity equivalency.
a. 1,3,5-Trimethylbenzene. 1,3,5-Trimethylbenzene was identified in
the record samples. EPA has adequate toxicological information to
develop a provisional health benchmark (i.e., RfD). The Agency has
developed a provisional RfD of 0.05 mg/kg/day for 1,3,5-
trimethylbenzene using a subchronic oral rat study, along with other
toxicological studies. In addition, the Agency has determined that the
provisional RfD developed for 1,3,5-trimethylbenzene is an appropriate
benchmark for 1,2,4-trimethylbenzene. These studies and the Agency's
supporting analysis for the provisional RfD can be found in the docket
supporting this rule. The Agency has conducted limited external peer
review of the provisional RfD and it is therefore subject to change.
A number of assumptions and extrapolations are used to derive the
provisional RfD, including extrapolating from short-term animal studies
to a chronic human exposure, and the selection of the critical study on
which to develop a health benchmark. The Agency requests comments on
the appropriateness of the provisional RfD and requests any additional
data on the toxicity of 1,3,5-trimethylbenzene.
b. Use of Structure-Activity Relationships. There are 15
constituents identified in the record samples for which EPA has found
no reliable health effects data to calculate health benchmarks for
carcinogenic and noncarcinogenic chemicals. Because of the lack of
health effects data on these constituents, the Agency used a structure-
activity analysis to identify surrogate chemicals, where possible, that
have reliable health benchmarks for use in the risk assessment. The
approach involves identifying a surrogate chemical that has similar
chemical structure, physical properties, and health effects information
as that of the constituent for which human health data and animal data
are either lacking or inadequate. The Agency used the surrogate health
benchmarks in the risk analysis to assess the potential impacts of the
constituents without benchmarks found in the wastestreams for the
following five constituents: 1-methylnaphthalene; t-butylbenzene;
butylbenzene; sec-butylbenzene; and 2-hexanone. The risk analysis did
not include an evaluation of potential impacts from the following
constituents because no appropriate surrogates with health benchmarks
could be found: indene; 2-methylnaphthalene; n-propylbenzene;
bromobenzene; dibenzofuran; aluminum (+3); cobalt; magnesium hydroxide;
magnesium oxide; and iron oxide. Based on this assessment none of these
constituents were of concern in any of the listing decisions in today's
proposal. Further discussion of this approach can be found in the
docket supporting this rule. The Agency is planning to conduct a peer
review of the surrogate analysis and, therefore, the health benchmark
is subject to change. See ADDRESSES section. The Agency requests
comment on this approach, and any additional toxicity information on
these compounds.
c. Use of Relative Potencies for Polynuclear Aromatic Hydrocarbons
(PAHs). The Agency has a verified cancer slope factor available for
only one PAH, benzo(a)pyrene. For the remaining PAHs evaluated in the
risk assessment supporting this rule, the Agency used two methods to
quantitatively estimate the relative potencies of other PAHs. The first
method, developed by EPA's Office of Health and Environmental
Assessment, is interim guidance for the quantitative risk assessment of
six PAHs. This guidance uses data from mouse studies to develop
relative carcinogenic potency estimates relative to benzo(a)pyrene. A
detailed description of the methodology and resulting rankings can be
found in ``Provisional Guidance for Quantitative Risk Assessment of
Polycyclic Aromatic Hydrocarbons,'' included in the docket supporting
today's rule. The second method the Agency used for the risk assessment
is a semi-quantitative scoring exercise organized by the Office of
Pesticides, Pollution Prevention and Toxic Substances. In this method,
experts independently reviewed available data and reached consensus
scoring on an additional 101 PAHs in terms of the compound's relative
potency using benzo(a)pyrene as the reference compound. The Agency
seeks comments on the uncertainties and limitations of both methods. A
more detailed discussion of the two methods can be found in the docket
supporting today's rule.
All HBLs and their bases for this listing determination are
provided in a document entitled ``Assessments of Risks from the
Management of Petroleum Refining Waste: Background Document,'' which
can be found in the RCRA docket for this rule at EPA Headquarters (see
ADDRESSES section).
2. Risk Analysis
a. Risk Characterization Approach. The risk characterization
approach follows the EPA Guidance on Risk Characterization (Habicht,
1992), and Guidance for Risk Assessment (EPA Risk Assessment Council,
1991), and Guidance for Risk Characterization (EPA Science Policy
Council, 1995). These guidance documents specify that EPA risk
assessments will be expected to include (1) the central tendency and
high-end portions of the risk

[[Page 57758]]
distribution, and (2) important subgroups of the populations such as
highly susceptible groups or individuals, if known, and (3) population
risk. In addition to the presentation of results, these guidance
documents also specifies that the results portray a reasonable picture
of the actual or projected exposures with a discussion of
uncertainties. These documents are available in the public docket for
this action (see ADDRESSES section).
b. Individual Risk. Individual risk descriptors are intended to
convey information about the risk borne by individuals within a
specified population and subpopulations. These risk descriptors are
used to answer questions concerning the affected population, and the
risk for individuals within a population of interest. The approach used
in this analysis for characterizing baseline individual risk included:
(1) identifying and describing the population of concern for an
exposure route; (2) determining the sensitivity of the model parameters
used in the risk estimation; (3) estimating central tendency and high-
end values for the most sensitive parameters in the risk estimation
procedures; and (4) calculating individual risk for likely exposure
pathways that provides a characterization of the central tendency and
high-end risk descriptor.
Descriptors of population risk are intended to convey information
about the risk borne by the population or population segment being
studied. These risk descriptors are used to answer questions concerning
the number of cases of a particular health effect that could occur
within the population during a given time period, the number of persons
or percent of the population above a certain risk level or health
benchmark (e.g., RfD or RfC), and risk for a particular population
segment.
The Agency performed a population risk analysis for impacts to the
affected community surrounding the refineries across the country. The
results of the analysis are discussed in Section VI.C.
c. Risk Assessment. The results of the risk assessment are
presented in waste-specific risk tables in each of the basis for
listing sections (Section III.G). The risk tables include the following
information: constituents of concern; estimated human health central
tendency and high-end risk for each constituent of concern associated
with the management scenarios; high, low, and average concentrations of
constituents found in this waste; the number of samples in which the
constituent was detected; and notes regarding potential sources of
uncertainty. In addition to assessing the risks associated with the
individual constituents found in the waste, the Agency presents the
combined potential risk of constituents that coexist in the waste, as
described in ``The Risk Assessment Guidelines of 1986,'' found in the
docket supporting today's rule. However, where sampling data or the
exposure analysis show compelling evidence that the constituents cannot
or do not occur together in the waste stream or at the receptor, the
Agency considered only the risk associated with the individual
constituent.
In addition to those compounds presented in the waste-specific risk
tables, the Agency's characterization data include other constituents
found in these wastes. The risk tables presented in this preamble
contain only those constituents which had adequate data for
quantitative risk assessment and which were found to present a risk of
concern. The complete list of constituents found in each of the wastes
generated from petroleum refining operations, an explanation of the
risk analysis process, and an explanation of EPA's development of the
target analyte list are presented in the background documents for this
rule, which are located in the RCRA Docket for this rulemaking (see
ADDRESSES section).
(1) Selection of Waste Management Scenarios. EPA's regulations at
261.11(a)(3)(vii) require the Agency to consider the risk associated
with ``the plausible types of improper management to which the waste
could be subjected'' because exposures to wastes (and therefore the
risks involved) will vary by waste management practice. The choice of
which ``plausible management scenario'' (or scenarios) to use in a
listing determination depends on a combination of factors which are
discussed in general terms in EPA's general policy statement on
hazardous waste listing determinations (59 FR 24530, December 22,
1994). EPA generally employed the elements of the policy in this
listing determination.
The following discussion explains the selection of plausible
management scenarios for the petroleum listing determination. The
Agency requests comment on its choice of plausible management scenarios
and on the possibility of using alternative plausible management
scenarios.
EPA's basic approach to selecting which waste management scenarios
to model for risk analysis in listing determinations is to examine
current management practices and assess whether or not other practices
are available and are reasonably expected to be used. Where a practice
is actually reported used, that practice is generally considered
``plausible'' and may be considered for potential risk. EPA then
evaluates which of these current or projected management practices for
each wastestream are likely to pose significant risk based on an
assessment of exposure pathways of concern associated with those
practices. There are common waste management practices, such as
landfilling, which the Agency generally presumes are universally
plausible for solid wastes and will assess it for risk. There are other
practices which are less common, such as land treatment, where EPA will
consider them plausible only where the disposal methods have been
reported to be practiced. In some situations, potential trends in waste
management for a specific industry suggest the Agency will need to
project ``plausible'' mismanagement even if it is not currently in use
in order to be protective of potential changes in management and
therefore in potential risk. Finally, there may be situations where
analysis shows no need to model any scenarios because, although
considered plausible management, no exposure potential exists.
In its study of the petroleum refining industry, EPA was able to
develop a comprehensive database of existing waste management
practices. All U.S. refineries that EPA was aware of were sent a RCRA
section 3007 questionnaire and all the active ones responded. This
allowed the Agency to conduct a careful analysis of how wastestreams
were managed in 1992. Based on discussions with industry, the Agency
also was able to project potential changes in these practices and thus
determine whether or not to include unused or little used practices in
the risk assessment.
Overall, the Agency found the reported waste management practices
for the industry to be numerous and varied. This required an assessment
of the existing (and potential) management of each wastestream to
determine which of those practices should be modeled for that
particular residual. Some wastestreams had special considerations
(e.g., rarity of practice, volumes managed, existing regulatory
coverage) associated with their management that had to be included in
the decision-making process. The description of such considerations is
included in the listing determination section for that wastestream.
Given the extensive amount of data collected for this industry, EPA
did not find it necessary to quantitatively model all currently used
waste management practices. Furthermore, for the reported management
practices that were

[[Page 57759]]
assessed for risk, EPA conducted risk analysis based on the volumes of
wastes reported to be managed by those practices in 1992. This is a
modification of EPA's general policy to consider plausible (and model)
all reported waste management practices. The reasons for the
modification, discussed in more detail later in this section, are:
1. Some practices involve very small volumes or very few generators
with a correspondingly low potential to cause unacceptable risk.
2. Some practices have proved in past listing determinations to
pose less risk than those more common practices (e.g., landfilling)
that were modeled. Therefore the modeled practices act as surrogates to
the less common, less risky alternatives.
3. Most of the reported management practices selected for modeling
are less expensive than other plausible alternatives (industry will
usually select and continue to use the less costly option) and
therefore there was no need to assess practices not currently used or
only rarely used.
4. The Agency was unable to model every reported management
practice for every metric ton of waste due to time and resource
constraints. However, EPA believes it has evaluated the practices
likely to be of most concern.
EPA's data show that the overwhelming volume of the wastestreams
that were actually disposed of (as opposed to being recycled or
reclaimed) involved three specific waste management practices:
discharge to a wastewater treatment plant, landfilling, and land
treatment. Each of these was reported to be currently in use by a
number of refineries.
(2) Disposal in Wastewater Treatment Plants. Exposure pathways and
potential risks associated with disposal of wastes to wastewater
treatment plants, which in this industry generally represents combined
wastestream treatment in tanks, are largely covered by regulation under
the NPDES or air permit programs. Furthermore, sludges generated by
refinery wastewater treatment systems, which could be affected by the
discharge of the wastestreams of concern in this listing, are already
listed hazardous wastes F037, F038, K048, and K051. The exception is
activated biological treatment (ABT) sludge and sludges generated
downstream of ABT units. These sludges can be disposed of in various
ways, including surface impoundments. However, activated biological
treatment sludge is not one of the residuals under consideration in
this listing. In addition, the volumes managed in the wastewater
treatment system of the residuals under consideration in this listing
are relatively small in comparison to the volumes typically handled in
refinery wastewater treatment systems. In addition, unlike most
refinery process wastewaters, these volumes are generated on an
intermittent (e.g., once a year) basis. The wastestreams of concern for
this listing would be considerably diluted by the other wastestreams
sent to the plant. Further, EPA has proposed that the risk associated
with disposal of these ABT and downstream sludges be covered by the
Phase IV Land Disposal Restrictions treatment requirements (60 FR
43654, August 22, 1995). For these reasons, discharge of wastes covered
by the consent decree to wastewater treatment systems, although a
practiced management scenario, was not modeled for risk.
(3) Disposal in Landfills and Land Treatment Units. The principal
waste management practices chosen for modeling the residuals in this
listing determination were off-site and on-site Subtitle D landfilling
and treatment in off-site and on-site land treatment units (LTUs).
These disposal practices were reported in the Section 3007
questionnaire survey to be in use by a large percentage of refineries
and for a large proportion of the total volume discarded. Therefore,
EPA modeled both direct and indirect exposure pathways associated with
these two waste management practices.
For on-site landfills and LTUs, the Agency used the data submitted
by industry in the Section 3007 questionnaire to characterize the units
in terms of the waste quantities disposed, surface area of disposal
units, and distances to receptors. For off-site landfills and LTUs, the
Agency used characteristics based on a statistical analysis of existing
Subtitle D land treatment facilities, from the Agency's ``Industrial
Subtitle D Facility Study'' (October 20, 1986).
The Agency modeled the releases from the disposal of wastes in on-
site and off-site land treatment units by partitioning the constituents
of concern between several fate and transport processes. These releases
include the following: volatilization to the air, leaching to ground
water, erosion of soil and runoff of dissolved constituents to nearby
land and surface water bodies, and biodegradation. For the screening or
bounding estimates, the Agency assumed that no partitioning or
biodegradation occurred, thus maximizing releases to all media; for
example, for the groundwater pathway's bounding analysis, TCLP results
were used as model inputs. For the central and high-end estimates of
risk, the Agency modeled the partitioning of these releases from the
land treatment units to derive annual concentrations in the media.
Biodegradation losses were calculated using data on constituent half-
life in the environment. The Agency's groundwater risk analysis used
the estimated leaching concentrations from this analysis, instead of
TCLP data, as the starting concentration in which to estimate
groundwater concentrations at a receptor well. The TCLP data that the
Agency collected estimate the concentration of the constituents
leaching from the waste samples in a landfill management scenario. The
Agency evaluated the land treatment scenario on a soil/waste mixture
for which the Agency did not have TCLP data and, therefore, relied on
the results of the partitioning analysis. A more detailed discussion of
the release processes for land treatment units is presented in the
``Assessment of Risks From the Management of Petroleum Refining Wastes:
Background Document'' in the docket supporting today's proposal.
(4) Other Disposal Practices Reported. There were other, less
commonly employed waste management practices reported in the petroleum
refining industry. Several residuals had ten or more different
management practices reported as ``in use.'' For most of them, EPA has
concluded that although they are used in the petroleum refining
industry, they are not management scenarios that need to be assessed
for risk. For example, there were ten reported management practices for
HF alkylation sludge. Four of these (representing 75% of the reported
waste volume) involved land treatment or disposal in a landfill and
were modeled for risk. One practice was on-site recovery in the coking
unit (12% of reported waste volume), two others involved practices
since terminated (10% of reported waste volume), and the remainder of
management practices involved discharge to the wastewater treatment
plant. These latter practices were not modeled. The factors the Agency
considered in deciding whether or not the less common disposal
practices should be modeled are:
i. Coverage of the characterization program. The comprehensive
nature of EPA's petroleum refining database allowed the Agency to
develop an in depth knowledge of the amounts of waste generated and the
final management practices employed by the petroleum refining industry.
In

[[Page 57760]]
particular, a very high percentage (more than 80 percent of the total
volume) of these wastestreams either were reused, reclaimed, or
recycled or were disposed of using landfilling or land treatment (more
than 50 percent of the remaining volume), suggesting that there are
financial and practical incentives to handle wastes using the methods
reported. These incentives were assumed to be constraints.
Moreover, the information indicated that aside from recycling,
landfilling, and land treatment, most reported management practices
involved low volumes of waste that would be of significantly less
concern in terms of risk. If possible given the potential risks
involved, EPA tries not to base listing determinations on disposal
practices employed by a very small segment of an industry producing low
volumes of waste as this can penalize unnecessarily, without a
concomitant benefit in actual risk reduction, the vast majority of
generators who dispose of the bulk of the wastes generated in less
risky ways. For example, if one plant reported one metric ton of a
wastestream as used as dust suppressant, but thousands of tons of that
wastestream were reported as landfilled by a number of other plants,
EPA would likely conclude that dust suppression, although nominally in
use, is not a practice that should be assessed for risk. In fact, EPA
was unable, due to resource and time constraints, to cover all waste
volumes reported with the plausible management scenarios selected for
modeling. Therefore, there are some reported management practices that
were not formally evaluated using predictive risk assessment models
after EPA judged them unlikely to be significant. Less formal
projections of potential risk were made for some management scenarios.
Also, experience in previous listings has indicated some waste
management practices show more risk than others. Therefore, if EPA
calculates risk for the usually more risky management scenario, the
risk from other scenarios will probably be lower.
ii. Effect of other regulatory programs. For some wastestreams and
their reported waste management practices, EPA concluded that existing
regulatory programs provided a level of regulatory coverage that
rendered further assessment of risk unnecessary. Many of these
wastestreams are often characteristically hazardous. In fact, the
Agency concluded that many of the wastestreams that were disposed of in
Subtitle C management facilities were sent there specifically because
they were characteristically hazardous wastes. Therefore, EPA believes
that the volumes sent to Subtitle C facilities would continue to be
handled in that way.
iii. Management costs. Where one management practice is generally
more expensive than another, cost becomes a factor in EPA's assessment
of whether or not that practice should be considered plausible. In this
industry, the Agency generally found that the lower cost management
option was currently the one employed and that factor further suggested
existing management practices would not change. The principal example
is incineration, which is a higher cost option than landfilling or land
treating. Little direct incineration of wastestreams was reported by
the industry. EPA concluded there was a negative cost incentive for the
industry to switch to incineration of these wastestreams. Additionally,
the petroleum refining industry reported little disposal of these
wastestreams in surface impoundments. Due to the industry's heavy
investment in wastewater treatment tanks, there appears to be little
incentive to switch to surface impoundments to treat and dispose of
wastestreams. Therefore, EPA only modeled surface impoundments in its
risk assessment for one wastestream.
Because of all of these factors, EPA determined it was unnecessary
either to project unreported management scenarios or to model many of
the infrequently reported management practices for this listing
determination. Instead, EPA determined it more appropriate to estimate
risk based on the most plausible, highest risk management practices and
therefore focused risk assessment modeling on landfilling and land
treatment.
During EPA's information collection process, it was pointed out to
the Agency that leaking tanks and refinery piping have been problems
for the petroleum industry and that exposures from such sources should
be modeled. Although such unintentional spills are not management per
se, exposures from such sources could be a concern. For the major
liquid wastestreams evaluated in today's proposal (e.g., spent sulfuric
acid and spent caustic), spills and leaks already fall under the
hazardous waste management system because these wastes are typically
characteristically hazardous. This obviates the need for conducting a
risk assessment for such pathways. For other wastestreams, EPA
concluded that the selection of unlined landfilling as a plausible
management scenario could serve as a surrogate for such sources because
the exposure scenario would be roughly similar. Leaks and spills of
wastestreams would cause exposures similar to those caused by landfills
(for potential groundwater contamination) or land treatment units (for
runoff or windblown dust). Because EPA modeled those management
scenarios, the Agency concluded additional modeling of leaks and spills
is unnecessary. Furthermore, such leaks and spills are typically
intermittent and should not present the long-term exposure potential
presented by land disposal.
The Agency evaluated each of the residuals of concern to determine
whether it was appropriate to model interim storage methods (e.g.,
tanks, containers, etc.) that are typically employed prior to final
management (e.g., landfilling). In most cases, the Agency determined
that the predominant exposure risks were expected to be associated with
long-term final management methods and that it was unnecessary to model
short-term interim storage. For example, many of the residuals of
concern are generated infrequently: the typical generation frequency
for tank sludges is once every ten years per tank and the catalyst
residuals are only generated every 2 to 5 years. For these types of
infrequently generated residuals, the residuals are typically stored
on-site for a period of time comparable to the tank or unit turnaround.
The Agency observed that these turnaround periods are often only 4 to 6
weeks in duration. Several factors contribute to the refineries'
motivation to move the residuals out of short-term storage: (1) the
residuals are often staged in the immediate vicinity of the process
area, impeding movement for continued operations; (2) the containers
used to transport the residuals (e.g., flo-bins, dumpsters, roll-off
bins) are often rented and incur substantial cost during usage; and (3)
turnarounds are often contracted out and the refineries are financially
motivated to minimize the length of time that they must pay for
contractor services and equipment, including storage units.
Because the on-site storage period is so short for many of the
infrequently generated residuals of concern, the Agency felt that it
was more appropriate to focus on assessing risk from long-term
management of these types of residuals. For those residuals, however,
that are generated on a more frequent basis, the Agency did model
certain storage practices. For example, spent caustic is generated on a
continual or frequent basis and is generally stored in tanks prior to
further management. These tanks are in continual usage. The Agency
modeled potential air releases from these spent caustic storage tanks
because of the potential for continual

[[Page 57761]]
toxicant releases. Similarly, sludge from sulfur complex operations can
be generated on a regular basis (e.g., weekly) and the Agency observed
facilities that maintain storage areas in the process units for
dumpsters used to accumulate filter cartridges. This practice also
poses the potential for ongoing air emissions and was modeled in EPA's
risk assessment.
Finally, the Agency notes that residuals from refining are, due to
their very nature, often reusable. They can be recycled, sold, or
transferred to other facilities. The disposition of these reusable
wastes is described in Section III.E. of this preamble. Because these
residuals are currently exempt or are proposed to be excluded from the
hazardous waste management system, exposures associated with their
management were not modeled in this listing determination. However, for
the wastestreams managed in an exempt manner that were assessed in this
listing determination, EPA has done qualitative risk analysis. Those
qualitative risk evaluations are described in the listing decision
rationales for the appropriate individual wastestream. Additionally,
the Agency did model air pathways for certain wastestreams when on-site
storage tanks were projected to be a potential source of air risk.
(5) Exposure Scenarios. The scenarios (i.e., receptors) included in
the risk assessment include adult resident, child resident, subsistence
fisher, recreational fisher, subsistence farmer, home gardener, and
consumers of ground water.
Adult Resident Applicable exposure pathways for the adult resident
include incidental ingestion of contaminated soil and direct inhalation
of vapors and particulates.
Child Resident Exposure pathways for the child resident are
identical to those for the adult resident. The rate of incidental soil
ingestion for the child, however, is twice that for an adult.
Recreational Fisher Applicable exposure pathways for the
recreational fisher include ingestion of contaminated fish, in addition
to exposure pathways of an adult resident (i.e., incidental ingestion
of contaminated soil, and direct inhalation of vapors and
particulates). Risks calculated for the recreational fisher were found
to be predominantly driven by the incidental ingestion of contaminated
soil; risks estimated through the ingestion of contaminated fish were
negligible by comparison. While the results for the recreational fisher
are presented in the risk assessment background document, they are not
presented in the preamble. The Agency is not using the subsistence
fisher scenario to support the listing determination proposed today.
Subsistence Fisher Applicable exposure pathways for the subsistence
fisher include ingestion of contaminated fish, in addition to exposure
pathways of an adult resident (i.e., incidental ingestion of
contaminated soil, and direct inhalation of vapors and particulates).
The rate of ingestion of fish for the subsistence fisher is twice that
for the recreational fisher. Risks calculated for the subsistence
fisher were also found to be predominantly driven by the incidental
ingestion of contaminated soil. The subsistence fisher risk assessment
results are available in the risk assessment background document in the
docket for this rule and are not presented in this preamble. The Agency
is not using the subsistence fisher scenario to support the listing
determination proposed today.
Subsistence Farmer Applicable exposure pathways for the subsistence
farmer include ingestion of home-grown beef and milk, ingestion of
home-grown fruits and vegetables, incidental ingestion of soil, and
direct inhalation of vapors and particulates. The total amount of beef,
milk, fruit, and vegetables that the subsistence farmer consumes is
assumed to be contaminated.
In conducting the subsistence farmer risk assessment, the Agency
determined that there is high uncertainty in the calculated plant-to-
animal (primarily beef and dairy cattle) bioconcentration factors for
the key constituents of concern, polynuclear aromatic hydrocarbons
(PAHs). No empirical data were found for bioaccumulation of PAHs in
mammals by this route; the model uses physical properties of
constituents (Kow) to predict transfer factors. For fish,
empirical data show that using Kow to predict bioconcentration
overestimates fish tissue concentrations by several orders of
magnitude. Based on these very high predicted bioconcentration factors,
the beef and dairy product ingestion pathways are major contributors to
cancer risk estimates for subsistence farmers. Because of the high
uncertainty associated with these bioconcentration factors, the Agency
is not using the subsistence farmer scenario to support the listing
determinations proposed today. The subsistence farmer scenario risk
assessment results are presented in the risk assessment background
document in the docket for this proposal but are not presented in the
preamble; the Agency requests comment and data regarding the
uncertainty associated with the bioconcentration factors of concern.
Home Gardener Applicable exposure pathways for the home gardener
include incidental ingestion of soil, direct inhalation of vapors and
particulates, and ingestion of fruits and vegetables. Forty percent of
the total amount of fruits and vegetables that the home gardener
consumes is assumed to come from their home garden which is assumed to
be contaminated.
Consumers of Ground Water These receptors are exposed only from
ingestion of untreated ground water contaminated by the leaching of
toxic constituents in the wastes being managed in land disposal units.
The Agency used a ground water fate and transport model, the EPACMTP
(EPA's Composite Model for Leachate Migration with Transformation
Products), to project the concentrations reaching the receptor well.
The EPACMTP is described in the background documents available in the
docket for today's proposal. See ADDRESSES section.
Chemicals in the subsurface may be subject to a variety of
biochemical transformation processes. EPACMTP accounts for
transformations due to hydrolysis, however, none of the organic
constituents considered in the present analysis are subject to
breakdown by hydrolysis. Biodegradation may be a significant removal
process for some of the constituents considered in the analysis.
However, the data and parameters associated with biodegradation are
subject to much greater uncertainty, vary over a wide range, and may be
highly site-specific. For these reasons, the Agency developed a
protocol for the determination of nationwide biodegradation rates,
which was published on June 15, 1988 (53 FR 22300). The protocol
requires biodegradation data from six sites that represent different
regions of the country. To date, the Agency has not received a complete
set of biodegradation rates for the constituents of concern
(particularly benzene). Therefore, biodegradation is not considered
directly in the groundwater pathway analysis. However, EPA evaluated
the potential effect of biodegradation using the available information
and best estimates.
Using the limited data available, EPA estimates that the benzene
concentration in well water is reduced by less than a factor of two
(reduction varies from 2 to 44 percent). Details of effects of benzene
biodegradation rates on modeling results for the different waste
streams are presented in

[[Page 57762]]
``Background Document for Groundwater Pathway Analysis'' available in
the docket. The Agency is soliciting comments on these rates and
requesting any biodegradation data, consistent with our protocol, which
can be used for nationwide modeling analyses.
3. Consideration of Uncertainty in Listing Determinations
One of the potential exposures of significant concern for this
rulemaking is erosion of soil from a land treatment unit onto adjacent
areas, including possible vegetable gardens. This type of exposure is
what the Agency refers to as ``indirect'' exposure, meaning that the
receptor (in this case a home gardener) is exposed to contaminants in
the waste after these contaminants have been transported from the waste
management area and have entered another environmental media (in this
case soil and vegetables) at the receptor site.
The Agency has used indirect exposure assessments in a number of
programs over the last several years. Some examples include the
development of the sewage sludge regulations, the development of
proposed standards for land application of paper mill sludge, and the
development of pesticide standards. In the hazardous waste listing
program, the Agency has considered indirect exposures for several
proposed regulations (wood surface protection, carbamate pesticides,
dyes and pigments) but has not based any final listing determinations
on risks from indirect exposures. These examples apply to national
regulations; in addition, the Agency has used indirect exposure
analyses on a site-specific basis in the Superfund program and to
develop hazardous waste combustion permit limits.
Despite its considerable experience with indirect exposure
assessments, the Agency recognizes that there are still significant
uncertainties associated with estimating the risks associated with some
exposure routes. Therefore, the Agency requests comment on how it
should factor in uncertainty in its listing determinations.
For example, if a risk estimate has a high degree of uncertainty
associated with it, should the Agency consider listing the waste in
question only if the calculated risk is near the high end of the risk
range of 10-6 to 10-4? Should the calculated risk estimate be even
higher? These questions imply that greater uncertainty generally
results in making a risk assessment more conservative. Is that
implication accurate? The Agency solicits comment on these questions
and this issue in general.
4. Peer Review
A peer review of the risk assessment for non-ground water pathways
has been performed. (The groundwater model was previously reviewed by
the Agency's Science Advisory Board.) Particular emphasis was placed on
the components that follow:

(1) Confidence in data on biotransfer factors for PAHs;
(2) Assumptions regarding design and operation of land treatment
units, including methods used to prevent excess build-up of
constituents in land treatment units;
(3) Methods used to predict soil concentrations at receptor
locations, with particular emphasis on the contribution of soil run-
off from land treatment units in which residuals are disposed and
the maintenance of a mass balance of constituents at the receptor
location; and
(4) Overall maintenance of mass balance of constituents among
multiple exposure pathways.

Three academic experts on risk assessment issues such as these were
selected to review the risk assessment for non-ground water pathways.
Comments have been received from these peer reviewers and will be
addressed concurrently with public comments on this proposed rule.

G. Waste-specific Listing Determination Rationales

1. Crude Oil Storage Tank Sediment
a. Summary. EPA is proposing to not list as hazardous tank sediment
from the storage of crude oil at petroleum refineries. This wastestream
does not meet the criteria set out at 40 CFR 261.11(a)(3) for listing a
waste as hazardous, because it does not pose a substantial or potential
hazard to human health and the environment. The Agency identified
limited risks to consumers of groundwater associated with releases from
off-site Subtitle D landfilling due solely to a single constituent,
benzene, which is already regulated under the Toxicity Characteristic
(TC). Home gardeners and adult residents show low risks from
polynuclear aromatic hydrocarbons (PAHs) potentially released from land
treatment operations. The risk assessment results are summarized in
Table III-2.

Table III-2.--Waste Characterization and Risk Estimates--Crude Oil Storage Tank Sediment
--------------------------------------------------------------------------------------------------------------------------------------------------------
On-site land treatment * Off-site land treatment * Waste characterization
--------------------------------------------------------------------------------------------------------------------------
Constituents of concern Central Central
tendency High end tendency High end Avg. conc. High conc. Low conc. # of pts. Notes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Home Gardener

--------------------------------------------------------------------------------------------------------------------------------------------------------
Benzo (a) pyrene............. 2E-9 9E-7 2E-9 1E-7 12.3 26.0 6.6 3 of 6...... J(2), 1
Dibenz (a,h), anthracene..... 9E-10 3E-7 7E-10 3E-8 2.1 3.7 .......... 1 of 6...... J(1), 1
Benzo (a) anthracene......... 4E-10 7E-8 3E-10 9E-9 11.5 31.0 .......... 1 of 6...... 1
Indeno (1, 2, 3-cd) pyrene... 2E-10 7E-8 1E-10 8E-9 15.0 15.0 3.0 2 of 6...... J(1)
Benzo (b) fluoranthene....... 3E-10 1E-7 3E-10 1E-8 11.4 29.0 5.9 2 of 6...... J(1), 1, 2
Total Carcinogen Risk***..... 4E-9 1E-6 3E-9 2E-7 .......... .......... ..........

--------------------------------------------------------------------------------------------------------------------------------------------------------
Adult Resident

--------------------------------------------------------------------------------------------------------------------------------------------------------
Benzo (a) pyrene............. 4E-9 7E-7 3E-9 9E-8 12.3 26.0 6.6 3 of 6...... J(2), 1
Dibenz (a, h) anthracene..... 2E-9 5E-7 2E-9 6E-8 2.1 3.7 .......... 1 of 6...... J(1), 1
Total Carcinogen Risk***..... 8E-9 1E-6 6E-9 2E-7 .......... .......... ..........
--------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
1. Detection limits greater than the highest detected concentration are excluded from the average concentration calculations.
2. Concentration for combined benzo(b)fluoranthene and benzo(k)fluoranthene. J(#) Samples were estimated concentrations below quantitation limits, ``#''
indicates number of samples that are ``J'' values.

[[Page 57763]]

Only the combination of high-end factors resulting in the greatest overall carcinogen risk are presented:
* Scenario: high-end factors of quantity, duration of exposure for all scenarios.
** Scenario: high-end factors of small area, duration of exposure for all scenarios.
*** Total carcinogen risk includes risks from other PAHs not tabulated. The risks for the PAHs not presented in this table are lower than those that are
presented.
All concentrations are in mg/kg.

Waste Characterization and Risk Estimates, Crude Oil Storage Tank Sediment
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
On-site land treatment Off-site land treatment Off-site landfill Waste characterization
---------------------------------------------------------------------------------------------------------------------------------------------------------------
Constituents of concern Central Central Central
tendency High end tendency High end tendency High end Avg. conc. High conc. Low conc. # of pts Notes
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Groundwater

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Benzene......................... -5) due to benzene for an adult consuming groundwater
contaminated from an off-site landfill. The high-end carcinogenic risks
from PAHs in the home gardener and adult resident pathways were 1E-6
for the on-site land treatment scenario. The central tendency estimates
did not show significant risk for any exposure scenario.
The Agency conducted another level of analysis of its risk results
to further evaluate the PAH risks that were identified for land
treatment. One of the major assumptions in the Agency's run-off models
for releases from land treatment units (LTUs) is that the unit does not
have controls for run-on and run-off waters from precipitation. A
significant portion of the predicted risk for the PAHs is associated
with contaminated soils washing off of the LTU into residential areas.
PAH risks are reduced below listing levels of concern if no run-on/run-
off is assumed (i.e., the refinery diverts all run-on and collects all
run-off). EPA's data collection effort showed most LTUs reported run-
on/run-off controls to be in place. A survey of some state programs,
however, showed that non-hazardous waste LTUs run-on/run-off controls
were voluntary.\6\ Permits were not required, nor were management
standards (where developed) mandatory. The Agency believes that an
assumption of complete run-on/run-off control would overstate reality
in that existing controls for Subtitle D land treatment units may be
inadequate to control all releases, including dike failures during
severe storm events, and, more routinely, tracking wastes from the unit
on trucks and earthmoving equipment. While the Agency does not have
information on the actual effectiveness of land treatment units at
controlling releases associated with run-on/run-off, the Agency
believes the risks may lie somewhere between those posed by scenarios
with and without controls. For crude oil storage tank sediment, LTU
controls that reduced off-site run-off to nearby residential areas
(e.g., by about 50%) would reduce the high-end risk from land treatment
to below the 10-6 level.

\6\ See ``Communications with State Authorities on Requirements
for Land Treatment Units,'' U.S. EPA 1995.
---------------------------------------------------------------------------

The Agency believes the management practices of most concern (land
treatment and landfills) were assessed, and that the other management
practices would not serve as a basis for listing. The wastes being
disposed of in Subtitle C landfills are already handled as hazardous
and should not present significant risk. As described in Section II.F.2
(``Risk Analysis''), EPA believes that potential risks associated with
disposal of wastes to wastewater treatment plants are largely covered
by existing regulations. In addition to the existing NPDES or air
programs: (1) Refinery sludges generated by wastewater treatment
systems are already listed hazardous wastes (K048, K051, F037, F038);
(2) the volumes of the crude oil storage tank residuals are relatively
small compared to volumes in refinery wastewater treatment systems; and
(3) residual risk associated with treatment would be covered by the
proposed Phase IV Land Disposal Restrictions treatment requirements.
Concerning on-site recovery for this waste, nearly all of this material
is currently excluded from the definition of solid waste because it is
reinserted into the refining process prior to distillation and
catalytic cracking. See Sec. 262.4(a)(12). A proposed expansion of this
exclusion and its rationale are discussed in Section III.E. of this
notice.
Today's listing determination is limited in scope to crude oil
storage tank sediment that is generated from storage tanks associated
with petroleum refineries, either on-site or at affiliated tank farms
(e.g., tank storage areas owned or under contract to the refinery). The
Agency is not attempting to evaluate sediments generated from the
storage of crude oil at exploration

[[Page 57764]]
and production sites or associated with pipelines or other crude oil
transportation conveyances. The Agency has not collected data necessary
to support a risk characterization of these non-refinery sediments and
is not, at this time, making a determination whether to

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A95-27693. Public record. Not legal advice.