Wednesday
 August 25, 1999
Part II



Environmental

Protection  Agency

40 CFR Parts 148, 261, 264, 265, 268,
271, and 302
Hazardous Waste Management System;
Identification and Listing of Hazardous
Waste; Chlorinated Aliphatics Production
Wastes; Land Disposal Restrictions for
Newly Identified Wastes; and CERCLA
Hazardous Substance  Designation and
Reportable Quantities; Proposed Rule

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         46476
Federal  Register/Vol. 64, No. 164/Wednesday, August 25,  1999/Proposed Rules
         ENVIRONMENTAL PROTECTION
         AGENCY

  !       40 CFR Parts 148, 261, 264,265,268,
         271, and 302
         [SWH-FRL-6413-4]
         R1N2050-AD85

         Hazardous Waste Management
         System; Identification and Listing of
         Hazardous Waste; Chlorinated
         Aliphatics Production Wastes; Land
  I       Disposal Restrictions for Newly
  I       Identified Wastes; and CERCLA
         Hazardous Substance Designation and
 I        Reportable Quantities
ill, '" i,  AGENCY: Environmental Protection
:;rj:	   Agency (EPA).
        ACTION: Proposed rule.

        SUMMARY: The EPA is proposing to list
  I      three of six wastes from the chlorinated
        aliphatics industry as hazardous wastes
        urider the, Resource Conservation and
        Recovery Act (RCRA), which directs
        EPA to determine whether certain
        wastes from the chlorinated aliphatics
        industry present a hazard to human
        nealth or the environment. The effect of
        listing these three wastes will be to
        subject them to stringent management
        arid treatment standards under RCRA
        and to subject them to emergency
        notification requirements for releases of
        hazardous substances to the
        environment. EPA is proposing a
        contingent-management listing
        approach for one of these wastes, and as
        one of two options for another of these
        wastes, such that waste generators will
        have the pption of their waste not being
        listed if it is sent to a specific type of
    | : \,,, management facility.
        DAJES: EpA will accept public
        comments on this proposed rule until
    	I	IJgyernber 23, 1999. Comments	
   •'.' £  pSi'tmarkecl 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 by September 8. 1999.
    ^ sn"" AM}RKSE§:ilf you wish to comment on
       tfjls proposed rule,  you must send an
     ,::!: original and two copies of the comments
       referencing docket number F-1999-
       CALP-FFFFF to: RCRA Docket
       Mprmation Center, Office of Solid
       Waste (5305G), U.S. Environmental
       Protection Agency Headquarters (EPA,
       .H.Q). 401 M Street, SW, Washington,
       D.C.  20460,. Hand deliveries of
       comments; should be made to the
       Arlington, VA, address listed in the
       fourth paragraph of SUPPLEMENTARY
       INFORMATION. You also may submit
       cbrnments electronically by sending
      electronic mail through the Internet to:
                       rcradocket@epamail.epa.gov. See the
                       beginning of SUPPLEMENTARY
                       INFpRMATION for instructions on
                       electronic submission.
                         You should not submit electronically
                       any confidential business information
                       (CBI). You must submit an original and
                       two copies of CBI under separate cover
                       to: RCRA CBI Document Control Officer,
                       Office of Solid Waste (5305 W), U.S.
                       EPA, 401 M Street, SW, Washington,
                       D.C. 20460. See the beginning of
                       SUPPLEMENTARY INFORMATION  for
                       information on viewing public
                       comments and supporting materials.
                         Address requests for a hearing to Mr.
                       David Bussard at: Office of Solid Waste,
                       Hazardous Waste Identification Division
                       (5304W), U.S. Environmental Protection
                       Agency, 401 M Street, SW, Washington,
                       D.C. 20460, (703)  308-8880.
                       FOR FURTHER INFORMATION CONTACT: For
                       general information, contact the RCRA
                       Hotline at (800) 424-9346 or TDD (800)
                       553-7672 (hearing impaired). In the
                       Washington, D.C., metropolitan area,
                       call (703) 412-9810 or TDD (703) 412-
                       3323. For information on specific
                       aspects of the rule, contact Ross Elliott
                       of the Office of Solid Waste (5304 W),
                       U.S. Environmental Protection Agency,
                       401 M Street, SW, Washington, D.C.
                       20460. [E-mail addresses and telephone
                       numbers: elliott.ross@epamail.epa.gov,
                       (703) 308-8748.]
                       SUPPLEMENTARY INFORMATION : You
                       should identify comments in electronic
                       format with the docket number F-1999-
                       CALP-FFFFF. You must submit all
                       electronic comments as an ASCII (text)
                       file, avoiding the use of special
                       characters and any form of encryption.
                       If you do not submit comments
                       electronically, EPA is asking
                       prospective commenters to voluntarily
                       submit one additional copy of their
                       comments on labeled personal computer
                       diskettes in ASCII  (text) format or a
                      word processing format that can be
                      converted to ASCII (text). It is essential
                      to  specify on the disk label the word
                      processing software and version/edition
                      as  well as the commenter's name. This
                      will allow EPA to convert the comments
                      into one of the word processing formats
                      utilized by the Agency. Please use
                      mailing envelopes  designed to
                      physically protect the submitted
                      diskettes. EPA emphasizes that
                      submission of comments on diskettes is
                      not mandatory, nor will it result in any
                      advantage or disadvantage to any
                      commenter. Supporting documents in
                      the docket for this Notice are also
                      available in electronic format on the
                      Internet. Follow these instructions to
                      access these documents.
  WWW: http://www.epa.gov/epaoswer/
    hazwaste/id
  FTP: ftp.epa/gov
  Login: anonymous
  Password: your Internet address
  Files are located in /pub/gopher/
    OSWRCRA.
    EPA will keep the official record for
  this action in paper form. Accordingly,
  we will transfer all comments received
  electronically into paper form and place
  them in the official record, 'which will
  also include all comments submitted
  directly in writing. The official record is
  the paper record maintained at the
  address in ADDRESSES at the beginning
  of this document.
   EPA responses to comments, whether
  the comments are written or electronic,
  will be in a notice in the Federal
  Register or in a response to comments
  document placed in the official record
  for this rulemaking. We will not
  immediately reply to commenters
  electronically other than to seek
  clarification of electronic comments that
  may be garbled in transmission or
  during conversion to paper form, as
  discussed above.
   You may view public comments and
 supporting materials in the RCRA
 Information Center (RIC), located at
 Crystal Gateway I, First Floor, 1235
 Jefferson Davis Highway, Arlington, VA.
 The RIC is open from 9 a.m. to 4 p.m.,
 Monday through Friday, excluding
 federal holidays. To review docket
 materials,  we recommend that you make
 an appointment by calling (703) 603-
 9230. You may copy a maximum of 100
 pages from any regulatory docket at no
 charge. Additional copies cost S0.15/
 page. For information on accessing
 paper and/or electronic copies of the
 document, see the first paragraph of the
 SUPPLEMENTARY INFORMATION section.
 Customer Service

 How Can I Influence EPA's Thinking on
 This Proposed Rule?
  In developing this proposal, we tried
 to address the concerns of all our
 stakeholders. Your comments will help
 us improve this rule. We invite you to
 provide different views on options we
 propose, new approaches we haven't
 considered, new data, how this rule may
 affect you, or other relevant information.
 We welcome your views on all aspects
 of this proposed rule, but we request
 comments in particular on the items
 indicated at the end of each section.
Your comments will be most effective if
you follow the suggestions below:
  • Explain your views as clearly as
possible and provide a summary of the
reasoning you used to arrive at your

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                Federal  Register/Vol. 64, No. 1647 Wednesday, August  25,  1999/ Proposed  Rules         46477
 conclusions, as well as examples to
 illustrate your views, where possible.
   • Provide solid technical and cost
 data to support your views.
   • If you estimate potential costs,
 explain how you arrived at your
 estimate.
   • Tell us which parts you support, as
 well as those with which you disagree.
   • Offer specific alternatives.
   • Reference your comments to
 specific sections of the proposal, such as
 the sections or page numbers of the
 preamble, or the regulatory citations.
   • Remember that your comments
 must be submitted by the deadline in
 this notice.
   • Include the name, date, and docket
 number with your comments.

 Contents of This Proposed Rule
   The contents of the preamble to  this
 proposed rule are listed in the following
 outline:
 I. Overview
 A. Who Potentially Will Be Affected by This
    Proposed Rule?
 B. Why Does This Rule Read Differently
    From Other Listing Rules?
 C. What Are the Statutory Authorities for
    This Rule?
 II. Background
 A. Schedule Suit
 B. Existing Chlorinated Aliphatics Listings
 HI. Today's Action
 A. Summary of Today's Action
  1. Scope of the Listing Determination
  2. Summary of the Proposed Listing
    Determinations
  3. Summary of the Remainder of This
    Preamble
 B. Description of the Industry
 C. Overview of EPA's Information Collection
    Activities
  1. Field Investigations and Sampling
  2. RCRA Section 3007 Survey
 D. What Are the Risks Associated With
    Management of Wastewaters and
    Wastewater Treatment Sludges From the
    Production of Chlorinated Aliphatic
    Chemicals?
  1. What Are the Risks for Potential Human
    Receptors?
  2. What Are the Potential Risks  for
    Ecological Receptors?
  3. Did EPA Conduct a Peer Review of the
    Risk Assessment?
E. Waste-Specific Listing Determination
    Rationales
  1. Chlorinated Aliphatics Wastewaters
   2. EDC/VCM Wastewater Treatment
     Sludges
   3. VCM-A Wastewater Treatment Sludges
   4. Methyl Chloride Wastewater Treatment
     Sludges
   5. Allyl Chloride Wastewater Treatment
     Sludges
 F. Constituents Proposed for Addition to
     Appendix VIII to 40 CFR Part 261
 IV. Economic Analysis
 A. What Is the Purpose of the Economic
     Analysis?
 B. How May the Public Participate in  the
     Economic Analysis?
 C. How Are Chlorinated Aliphatic Chemicals
     Used in the Economy?
 D. Where Are CAHCs Manufactured in the
     United States?
 E. Have CAHCs Been Produced Historically
     in Other Locations in the United States?
 F. What Are the Estimated Potential Industry
     Costs of This Listing?
 V. Proposed Treatment Standards Under
 RCRA's Land Disposal Restrictions
 A. What Are EPA's Land Disposal
     Restrictions (LDRs)?
 B. How Does EPA Develop LDR Treatment
     Standards?
 C. What Kind of Treatment Standards  Are
     Proposed?
 D. Other LDR-Related Provisions
 E. What Standards Are Proposed for K173?
 F. What Standards Are Proposed for K174?
 G. What Standards Are Proposed for K175?
 H. What Other Land Disposal Restrictions
    Aspects Are There to the Proposal?
 I.  Is There Treatment Capacity for the
    Proposed Wastes?
 VI. Compliance Dates
 A. Notification
 B. Interim Status and Permitted Facilities
 VII. State Authority
 A. Applicability of Rule in Authorized  States
 B. Effect on State Authorizations
 VIII.  Designation of Chlorinated Aliphatic
 Wastes (K173, K174 and K175) Under the
 Comprehensive Environmental Response,
 Compensation, and Liability Act (CERCLA)
 A. What Is the Relationship Between RCRA
   and CERCLA?
 B.  Is  EPA Proposing To Add Chlorinated
   Aliphatic Wastes to CERCLA?
 C.  How Does EPA Determine Reportable
   Quantities?
D.  When Do I Need to Report a Release  of
   K173, K174 or K175 Under CERCLA?
E.  What if I Know the Concentration of  the
   Constituents in My Waste?
  F. How Did EPA Determine the RQs for K173,
     K174 and K175 and Their Hazardous
     Constituents?
  G. How Do I Report a Release?
  H. What Is the Statutory Authority for This
     Program?
  I. How Can I Influence EPA's Thinking on
     Regulating K173, K174 and K175 Under
     CERCLA?
  IX. Administrative Assessments
  A. Executive Order 12866
  B. Regulatory Flexibility Act
  C. Paperwork Reduction Act
  D. Unfunded Mandates Reform Act
  E. Executive Order 12875: Enhancing the
     Intergovernmental Partnership
 F. Executive Order 13084: Consultation and
     Coordination With Indian Tribal
     Governments
 G. Executive Order 13045: Protection of
     Children From Environmental Risks and
     Safety Risks
 H. National Technology Transfer and
     Advancement Act of 1995
 I. Executive Order 12898: Environmental
    Justice

 I. Overview

 A. Who Potentially Will Be Affected by
 This Proposed Rule?

   Beginning January 1, 1999 all
 documents related to USEPA's
 regulatory, compliance and enforcement
 activities including rules, policies,
 interpretive guidance, and site-specific
 determinations with broad application,
 should properly identify the regulated
 entities, including descriptions that
 correspond to the applicable SIC codes
 or NAICS codes (source: 09 October
 1998 USEPA memo from Peter D.
 Robertson, Acting Deputy Administrator
 of USEPA). Today's action, if finalized,
 could potentially affect those who
 handle the wastes that EPA is proposing
 to add to the Agency's list of hazardous
 wastes under the RCRA program. This
 action also may affect entities that may
 need to respond to releases of these
wastes as CERCLA hazardous
substances. These potentially-affected
entities are described in the Economics
Background Document placed in the
docket in support of today's proposed
rule; a summary is shown in the table
below.
  SUMMARY OF FACILITIES POTENTIALLY AFFECTED BY THE USEPA's 1999 CHLORINATED ALIPHATICS MANUFACTURING
                    WASTE  LISTING PROPOSAL ACCORDING TO APPLICABLE SIC AND NAICS CODES


Item
1 	
2 	

Parent
company
SIC code
1311
1400


Industry sector name
Mining: Crude petroleum and natural gas 	
Mining: Nonmetallic minerals, except fuels 	 _ 	
Number of
U.S.
relevant
CAHC mfg.
facilities*
3
2

Parent
company
NAICS code
equivalent**
911111
212300

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        46478
               Federal Register/Vol. 64, No.  164/Wednesday, August 25, 1999/Proposed Rules
          SUMMARY OF FACILITIES POTENTIALLY AFFECTED BY THE USEPA's 1999 CHLORINATED ALIPHATICS MANUFACTURING
                     WASTE LISTING PROPOSAL ACCORDING TO APPLICABLE SIC AND NAICS CODES—Continued
Item
3 	 , 	
4 	
§ 	
6 	
7 	
8 	 	
8 	
10 	 	
1! 	 	


Parent
company
SIC code
2295
2800
2810
2812
2821
2851
2869
2911
3600


Industry sector name
Manufacturing: Coated fabrics, not rubberized 	
Manufacturing: Chemicals & allied products 	
Manufacturing: Chemicals & allied products
Manufacturing: Alkalies & chlorine manufacture
Manufacturing: Plastics materials & resins ....
Manufacturing: Paints & allied products . .
Manufacturing: Industrial organic chemicals, nee 	
Manufacturing: Petroleum refining 	
Manufacturing: Electronic & other electric equipment .

Total Applicable Facilities 	
Number of
U.S.
relevant
CAHC-rnfg.
facilities*
•)

1
•j
0
•]
•)
•)
•)

23
Parent
company
NAICS code
equivalent**
0-1 OOO
*aocnnn
oocnnn
OOC-iO-1
OOCO1 1

OOC-1 4
0041 1
oocnnrj


	I	;
  •The number of relevant facilities is based on the (a) type of CAHC products manufactured, (b) types of wastes generated, and (c) baselin
waste management practices, in relation to the terms and conditions of the proposed listing options. However, all CAHC manufacturing facilitie
in each industrial sector code may not be affected by the proposed listing options.
  "OSW-EMRAD derived the  NAICS code equivalents above from the SIC-to-NAICS conversion tables provided by the US Department of
Commerce, Bureau of the Census, at the following website: http://www.census.gov/epcd/www/naicstab.htm. There is no direct match in the SIC-
NAICS conversion tables for SIC codes 1400, 2800, 2810, and 3600, so a generalized six-digit NAICS code is provid
       cases.
                                                                                                 provided above for these four
         The list of potentially affected entities
       in the above table may not be
       exhaustive.  Our aim is to provide a
       guide for readers regarding entities
       likely to* be regulated by this action.
       This table lists those entities that EPA
       is aware potentially could be affected by
       this action. However, this action may
       affect other entities not listed in the
       table. To determine whether your
       facility is regulated by this action, you
       should examine 40 CFR 260 and 261
       carefully in concert with the proposed
       rules amending RCRA that are found at
       the end of this Federal Register notice.
       If you have questions regarding the
       applicability of this action to a
       particular entity, consult the person
       listed in the  preceding section entitled
       FOR FURTHER INFORMATION
       CONTACT.
       B. Why Does This Rule Read Differently
       From Other Listing Rules?

         Today's proposed listing
       determination preamble and regulations
       are written in "readable regulations"
       format. The authors tried to use active
       rather than passive voice, plain
       language, a question-and-answer format,
       the pronouns "we" for EPA and "you"
       for the owner/generator, and other
       techniques to make the information in
       today's rule easier to read and
       understand. This new format is part of
       the Agency's efforts at regulatory
       reinvention, and it makes today's rule
       read differently from other listing rules.
       The Agency believes that this new
       format will increase readers' abilities to
       understand the regulations, which
      should then increase compliance, make
                                       enforcement easier, and foster better
                                       relationships between EPA and the
                                       regulated community.

                                       C. What Are the Statutory Authorities
                                       for This Rule?
                                        These regulations are being proposed
                                       under the authority of Sections 2002(a),
                                       3001 (b), 3001 (e) (2) and 3007(a) of the
                                       Solid Waste Disposal Act, 42 U.S.C.
                                       6912(a), 692l(b) and (e)(2), and 6927(a)
                                       as amended several times, most
                                       importantly by the Hazardous and Solid
                                       Waste Amendments of 1984 (HSWA).
                                       These statutes commonly are referred to
                                       as the Resource Conservation and
                                       Recovery Act (RCRA), and are codified
                                       at Volume 42 of the United States Code
                                       (U.S.C.), Sections 6901 to 6992(k) (42
                                       U.S.C. 6901-6992(k)).
                                        Section 102 (a) of the Comprehensive
                                      Environmental Response,
                                      Compensation, and Liability Act of 1980
                                       (CERCLA), 42 U.S.C. 9602(a) is the
                                      authority under which the CERCLA
                                      aspects of this rule are being proposed.

                                      II. Background

                                      A. Schedule Suit
                                        In 1989, the Environmental Defense
                                      Fund (EDF) sued the Environmental
                                      Protection Agency (EPA), in part for
                                      failing to meet the statutory deadlines of
                                      Section 3001 (e) (2) of RCRA (EDF vs.
                                      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 has been amended
                                      several times to revise dates. The
                                      consent decree sets put deadlines for
                                      promulgating certain RCRA rules and
                                      for completing certain studies and
 reports. Paragraph 1. m. of the consent
 decree obliges EPA to propose a
 hazardous waste listing determination
 for wastewaters and wastewater
 treatment sludges generated from the
 production of specified chlorinated
 aliphatic chemicals. The wastewater
 and wastewater treatment sludges
 subject to the consent decree are those
 from the production of chlorinated
 aliphatics for which other process
 wastes already have been designated as
 hazardous waste F024 in 40 CFR 261.31.
 According to the consent decree, EPA
 must propose listing determinations by
 July 30,  1999 and promulgate final
 listing determinations on or before
 September 30, 2000. Today EPA is
 proposing listing determinations for
 these wastes in accordance with the
 consent decree.

 B. Existing Chlorinated Aliphatics
 Listings

  Today's proposal does not affect the
 scope of the chlorinated aliphatics
 process wastes that already have been
 listed as hazardous in prior EPA
 rulemakings. These wastes include
 wastes designated as hazardous waste
 code F024 as well as a number of other
 chlorinated aliphatic wastes listed
 below in Table II-1. EPA is not
 soliciting comment on these existing
 hazardous waste listings and does not
 intend to respond to such comments, if
received.
  Likewise, EPA is not soliciting
comments in today's rule on the
applicability of the existing chlorinated
aliphatics listings to the provisions of
CERCLA. Wastes listed as hazardous

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                 Federal Register/Vol. 64, No. 164/Wednesday, August 25,  1999/Proposed Rules
                                                                         46479
  under RCRA are by definition hazardous
  substances under CERCLA, and are
  included in the list of hazardous
  substances in 40 CFR 302.4, along with
  their corresponding reportable
  quantities ("RQs"). Hazardous
  substance RQs are those quantities of
  the designated chemical or waste that
  trigger certain reporting requirements if
  released to the environment. The
  previously listed hazardous wastes from
  chlorinated aliphatics production and
  their corresponding RQs are listed
  below in Table II-1.
     TABLE 11-1.—LIST OF CURRENTLY-REGULATED CHLORINATED ALIPHATIC PROCESS WASTES AND CORRESPONDING
                             REPORTABLE QUANTITIES AS CERCLA HAZARDOUS SUBSTANCES
                                            Hazardous substance
                                                                     RQ pounds
                                                                       (KG)
  F024—Process wastes, including but not limited to, distillation residues, heavy ends, tars, and reactor cleanout wastes from the
   production of certain chlorinated aliphatic hydrocarbons, by free radical catalyzed processes. These chlorinated aliphatic hy-
   drocarbons are those having carbon chain lengths ranging from one to and including five, with varying amounts and positions
   of chlorine substitution. [This listing does not include wastewaters, wastewater treatment sludges, spent catalysts and wastes
   listed in 40 CFR 261.31 or 261.32.]  	'.	
  F025—Condensed light ends, spent filters and filter aids, and spent dessicant wastes from the production of certain chlorinated
   aliphatic hydrocarbons, by free radical catalyzed processes. These chlorinated aliphatic hydrocarbons are those having car-
   bon chain lengths ranging from one to and including five, with varying amounts and positions of chlorine substitution	
  K016—Heavy ends or distillation residues from the production of carbon tetrachloride.	..'.......	
  K018—Heavy ends from the fractionation column in ethyl chloride production	
  K019—Heavy ends from the distillation of ethylene dichloride in ethylene dichloride production	
  K020—Heavy ends from the distillation of vinyl chloride in vinyl chloride monomer production	".".".'.'.'.'".".
  K028—Spent catalyst from the hydrochlorinator reactor in the production of 1,1,1-trichloroethane	
  K029—Waste from the product steam stripper in the production of 1,1,1-trichloroethane	
  K030—Column bottoms or heavy ends from the combined production of trichloroethylene and perchloroethylene	!..!"."!.".""."
  K095—Distillation bottoms from the production of 1,1,1-trichloroethane	
  K096—Heavy ends from the heavy ends column from the production of 1,1,1-trichloroethane	'.".'.
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
                                                                        1 (0.454)
 III. Today's Action
 A. Summary of Today's Action

 1. Scope of the Listing Determination
   Aliphatic hydrocarbons are
 compounds composed of the atoms of
 hydrogen and carbon, where the carbon
 atoms are linked by covalent bonds in
 an open-chain (straight and branched)
 structure, and those cyclic compounds
 that resemble the open-chain
 compounds. Aliphatics are
 distinguished from aromatic
 hydrocarbons, which are defined as
 benzene and compounds that resemble
 benzene in chemical behavior.  For an
 aliphatic to be chlorinated, one or more
 hydrogen atoms have been chemically
 replaced with chlorine atoms. The
 chlorinated aliphatic chemicals, the
 wastes of which are described in the
 (existing) F024 listing description, and
 identified in the consent decree, are
 those produced by free-radical catalyzed
 processes with  carbon chain lengths
 ranging from one to five.
  EPA performed an initial review and
 investigation of the waste categories
 identified in the consent decree, as well
 as a review of chlorinated aliphatics
 production processes and the
 wastewaters and wastewater treatment
 sludges generated by these processes.
 The Agency decided, for the purpose of
 studying chlorinated aliphatic wastes, to
 divide the wastestreams into several
 distinct waste groupings. Waste
groupings were defined to differentiate
between unique residuals, as well as to
 differentiate between unique
 management practices (e.g., on-site land
 treatment) and/or particular
 constituents (e.g., mercury). The Agency
 segregated chlorinated aliphatics
 wastewaters into two groupings, with
 one group being wastewaters generated
 from the production of vinyl chloride
 monomer using mercuric chloride
 catalyst in an acetylene-based process.
 These wastewaters were evaluated as
 one group due to the unique nature of
 this production process, the fact that
 these wastewaters are treated in a
 dedicated wastewater treatment system,
 and the presence of mercury in the
 wastestream. All other chlorinated
 aliphatic wastewaters were included in
 a second group and evaluated
 collectively. The Agency found that
 many producers of chlorinated
 aliphatics  manufacture several different
 chlorinated aliphatic products at a
 single facility and commingle the
 wastewaters generated by all processes
 prior to treatment in a single wastewater
 treatment system.
  The Agency identified four waste
 groupings for wastewater treatment
 sludges generated by the chlorinated
 aliphatics industry. These waste
 groupings were defined based primarily
 upon the particular management
 practices used to manage the wastes, but
 also based  on particular production
 processes. The Agency identified four
waste groups for chlorinated aliphatics
wastewater treatment sludges. These
waste groups include sludges generated
 from the treatment of wastewaters from
 the production of:
   • Ethylene dichloride and/or vinyl
 chloride monomer (EDC/VCM);
   • Vinyl chloride monomer using
 mercuric chloride catalyst in an
 acetylene-based process (VCM-A);
   • Methyl chloride; and
   • allyl chloride.
   The scope of today's notice does not
 include any other process residuals
 generated by  the chlorinated aliphatics
 industry. In particular, the Agency is
 not re-evaluating previous listing •
 determinations concerning wastes
 generated by  chlorinated aliphatics
 production processes.
   The Agency also points out that the
 consent decree specifies that this listing
 determination "shall include
 wastewaters and wastewater treatment
 sludges generated from the production
 of chlorinated aliphatics specified in the
 F024 listing"  (a listing which is limited
 to wastes from chlorinated aliphatic
 production using the "free radical
 catalyzed process" but does not include
 wastewaters or wastewater treatment
 sludges). However, for today's proposed
 rule the Agency did not restrict its
 evaluation of wastewaters and
 wastewater treatment sludges to only
 those generated from chlorinated
 aliphatics manufacturers using the free
 radical catalyzed process. In the
rulema'king for the F024 listing (which
 includes process wastes such as
distillation residues, heavy ends, and
tars, but not wastewaters and

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 46480
Federal Register/Vol. 64, No.  164/Wednesday, August 25, 1999/Proposed Rules
 wastewater treatment sludges) we found
 that there were distinct differences in
 the amount and type of chemical
 constituents present in these production
 wastes as a direct result of the
 production process used. For example,
 the free radical catalyzed reactions
 tended to produce unwanted organic
 compounds, as well as the desired
 chemical product, because this type  of
 reaction is less specific (in terms of
 desired product) than other types of
 processes used. As a result, the
 chemical constituents  that were the
 basis for listing F024 includes many
 organic compounds that are more
 prevalent in process wastes (again, tars,
 heavy ends, etc.) generated from the  free
 radical catalyzed process.
   However, in developing the
 information for today's proposed listing,
 EPA was concerned that limiting the
 scope of the investigation to free radical
 catalyzed processes might not be
 appropriate because of the different
 nature of wastewaters and wastewater
 treatment sludges as compared with the
 F024 process wastes. Wastewaters may
 be generated in different ways,
 including from scrubber waters,  cooling
 waters, as well as reaction media, etc.
 Ultimately, our primary reason for not
 restricting our evaluation of wastewaters
 and wastewater treatment sludges to
 those generated by free radical catalyzed
 processes is that our preliminary
 analysis of these wastes indicated that
 the constituents of concern (i.e.,
 dioxins, chloroform, arsenic) were not
 the same as the constituents of concern
 associated with the previously-listed
 F024 and F025 wastes.  In those previous
 listing determinations (which did not
 include wastewaters or wastewater
 treatment sludges) the Agency was able
 to distinguish risk levels of concern
 based upon particular production
 processes,
  In the case of today's proposed listing
 determination, we were not able to
 make such a distinction. The primary
 constituents of concern in the wastes  we
 are proposing to list as hazardous in
 today's notice are dioxins, whereas
 dioxins were not a basis for listing the
 F024 and F025 wastes. Data currently
 available to the Agency does not
 support a conclusion that wastewaters
 and wastewater treatment sludges
 generated by free radical catalyzed
 processes have significantly different
 concentrations of dioxins than other
 types of production processes used to
 manufacture chlorinated aliphatics.
 However, EPA requests  comment and
 data addressing the issue of whether one
 type of manufacturing process (e.g., free
radical catalyzation) versus all other
potential processes (e.g., ionic catalyzed
                        processes) would result in different
                        levels of dioxins in the resulting
                        wastestream. The Agency will consider
                        modifying the listing description
                        proposed in today's rulemaking as
                        appropriate to account for distinctions
                        identified in information available to
                        EPA at the time of the final rule.

                        2. Summary of the Proposed Listing
                        Determinations

                          In today's notice, EPA is proposing to
                        add three wastes generated by the
                        chlorinated aliphatics industry to the
                        list of hazardous wastes in 40 CFR
                        261.32. Below are the wastestreams EPA
                        is proposing to list as hazardous with
                        their corresponding proposed EPA
                        Hazardous Waste Numbers.
                        K173  Wastewaters from the production of
                           chlorinated aliphatic hydrocarbons,
                           except for wastewaters generated from
                           the production of vinyl chloride
                           monomer using mercuric chloride
                           catalyst in an acetylene-based process.
                           This listing includes wastewaters from
                           the production of chlorinated aliphatic
                           hydrocarbons that have carbon chain
                           lengths ranging from one to, and
                           including five, with varying amounts
                           and positions of chlorine substitution.
                        K174  Wastewater treatment sludges from
                           the production of ethylene dichloride or
                           vinyl chloride monomer (EDC/VCM).
                        K175  Wastewater treatment sludges from
                           the production of vinyl chloride
                           monomer using mercuric chloride
                           catalyst in an acetylene-based process.

                          EPA is proposing to list these wastes
                        because these residuals meet the criteria
                        set out in 40 CFR 261.11 (a) (3) for listing
                        a waste as hazardous. EPA assessed and
                        considered these criteria for all six
                        wastestreams through the use of risk
                        assessments and risk modeling, as well
                        as a consideration of other pertinent
                        factors. Today's proposed listing
                        determination follows the elements of
                        the Agency's listing decision policy that
                        was presented in the proposed listing
                        for wastes generated by the dye and
                        pigment industries published in the
                        Federal Register on December 22, 1994
                        (see 59 FR 66073). This policy uses a
                        "weight-of-evidence" approach in
                       which calculated risk information is a
                       key factor considered in making a listing
                       determination.
                         Upon promulgation of these proposed
                       listings, wastes meeting the listing
                       descriptions will become hazardous
                       wastes and need to be managed in
                       accordance with RCRA subtitle C
                       requirements. Residuals from the
                       treatment, storage, or disposal of the
                       wastewater treatment sludges proposed
                       to be listed as hazardous also will be
                       classified as hazardous wastes pursuant
                       to the "derived-from" rule (40 CFR
  261.3(c)(2)(i)).'Also, with certain
  limited exceptions, any mixture of a
  listed hazardous waste and a solid waste
  is itself a RCRA hazardous waste (40
  CFR 261.3(a)(2)(iv), "the mixture rule").
    In today's notice, the Agency is
  proposing an alternatfve approach to
  listing two of the wastes from
  chlorinated aliphatics processes as
  hazardous, rather than proposing to list
  these wastes in accordance v/ith the
  Agency's traditional listing approach.
  The Agency is proposing a conditional
  listing approach for one waste, and as
  one of two alternative approaches for a
  second waste, because the Agency has
  evaluated the ways in which the wastes
  are likely to be managed and has
  determined that certain waste
  management activities would present
  significant risks but that others would
  be protective of human health and the
  environment. Under a contingent
  management approach, EPA is
 proposing to list particular wastes as
 hazardous only if the wastes are
 managed in a way other than the
 manner in which the Agency has
 determined is protective of human
 health and the environment. In
 implementing a conditional-listing
 approach, the Agency is proposing that
 wastes that fall outside the scope of the
 listing description (e.g., are destined for
 the appropriate type of disposal) are
 non-hazardous when generated.
 However, if it turns out that the waste
 actually is not handled in accordance
 with the conditions of the listing at any
 point in its management, the generators
 or other handlers of the waste would be
 subject to various enforcement actions
 or, depending on the violations, the
 waste could become a hazardous waste
 and may even be considered hazardous
 from the point of generation. The
 Agency's proposed conditional-listing
 approach for wastes generated from
 chlorinated aliphatics processes is
 further discussed in section III.E of
 today's notice.
   Today's action also proposes not to
 list as hazardous the following three
 wastes:
   •  Process wastewaters from the
 production of vinyl chloride monomer
 using mercuric chloride catalyst in an
 acetylene-based process,
   •  Wastewater treatment sludges from
 the production of methyl chloride, and
  1 As explained later in this notice, residuals
generated from the management of wastewaters
proposed to be listed as hazardous (i.e., wastewater
treatment sludges) will not be subject to the
derived-from rule due to the fact that EPA
conducted separate investigations of these residuals
and they are the subject of independent listing
determinations.

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                                                                       46481
    • Wastewater treatment sludges from
  the production of allyl chloride.

  3. Summary of the Remainder of this
  Preamble
    Section III.B. describes the
  chlorinated aliphatics industry. Section
  III.C. describes how the information was
  gathered in support of today's proposed
  rule. Section III.D. is a description of the
  risk assessment performed for three of
  the wastes evaluated in today's rule,
  including chlorinated  aliphatic
  wastewaters, EDC/VCM sludges, and
  methyl chloride sludges, and the results
  of these assessments. Section III.E
  provides the rationale  for the proposed
  listing decisions for all six wastes
  analyzed in today's rule. Because full
  risk analyses were not  necessary for
  VCM-A wastewaters, VCM-A
  wastewater treatment sludges, or allyl
  chloride sludges, we discuss our
  assessment of risks attributable to each
  of these wastes in the same sections
  where we describe our listing decisions
  for the wastes. Section IV contains the
  economic assessment of the industry
  and the estimated impact of today's
  proposed listing determinations. Section
  V describes the proposed land disposal
 restriction requirements for those wastes
 we propose to list as hazardous, along
 with determinations of whether there is
 adequate treatment and disposal
 capacity for these wastes. Sections VI
  (compliance dates), VII (state authority),
 VIII (designating CERCLA hazardous
 substances) and IX (administrative
 assessments) discuss other analyses
 required by statute and various
 executive orders.
 B. Description of the Industry
   In 1992, when EPA began gathering
 information about the U.S. chlorinated
 aliphatics industry, it consisted of 27
 facilities owned by 20 corporations.
 However, as a result of  information
 updates in 1997, we determined that
 two chlorinated aliphatics facilities had
 closed and two additional facilities
 manufacture de minimis quantities of
 chlorinated aliphatics, lowering the
 number of facilities affected by today's
 proposed rulemaking to 23 and
 corporations to 19.
   Chlorinated aliphatics production
 facilities are located primarily in and
 around the petroleum/petrochemical
 industry which generally is located
 along the Gulf Coast. The majority of
 facility locations are fully integrated
 petrochemical processing facilities. A
 few facilities are co-located with other
 chemical manufacturing and/or
 petroleum refining facilities. These
 integrated facilities often manage wastes
generated across different production
  processes within the same waste
  management systems. For example,
  these facilities often combine
  chlorinated aliphatic wastewaters with
  non-chlorinated aliphatics wastewaters
  prior to treatment. The combined
  wastewater treatment system generates a
  commingled sludge. In addition, there
  are facilities that manage chlorinated
  aliphatics wastewaters in separate or
  dedicated wastewater treatment
  systems. For the purpose of this listing
  determination, the Agency refers to
  these treatment systems, and resulting
  sludges, as "dedicated" systems and
  "dedicated" sludges.
    Nearly  10 million metric tons of
  chlorinated aliphatics were produced in
  1996. More than 85 percent of the
  chlorinated aliphatic products
  manufactured in 1996 was ethylene
  dichloride and vinyl chloride monomer
  (EDC/VCM) manufactured via the
  "balanced process." This process
  involves the production of EDC as an
  intermediate product using direct
  chlorination and oxyhydrochlorination
  of ethylene, followed by cracking to
  produce VCM. Other chlorinated
  aliphatics production includes
  chlorinated methanes, methyl chloride,
  and a variety of other products.
 C. Overview of EPA's Information
 Collection Activities
   EPA's investigation of the wastes
 generated by the chlorinated aliphatics
 industry can be characterized in terms
 of two major information collection
 efforts: field investigations and survey
 evaluation. The Agency's field
 investigations included engineering site
 visits, "familiarization sampling"
 (sample collection and analysis to gain
 a preliminary understanding of the
 nature and concentration of potential
 constituents of concern), and "record
 sampling" (sample collection and
 analysis to provide data to use in
 assessing the potential risks posed by
 the wastes). The survey effort included
 the development, distribution, and
 assessment of an extensive industry-
 wide RCRA Section 3007 survey. Each
 of these efforts is summarized below.
 1. Field Investigations and Sampling
  EPA initiated its work activities with
 a series of engineering site visits. The
 primary purpose of the site visits was to
 gather information on chlorinated
 aliphatic manufacturing processes and
 the generation, management, and
 characterization of the consent decree
 wastes. In addition, the field teams
 identified potential record sampling
locations. The Agency conducted site
visits at 16 facilities prior to record
sampling; site visit facilities were"
  selected based on a goal of obtaining
  first hand information from a
  representative sampling of all
  chlorinated aliphatic manufacturers as
  well as all relevant manufacturing and
  waste management processes, including
  an investigation of dedicated
  wastewater treatment units.
    Concurrently, the Agency initiated the
  analytical phase of this listing
  determination with the development of
  a Quality Assurance Project Plan
  (QAPjP) for sampling and analysis,
  followed by collection of 15
  familiarization samples from three
  different manufacturing facilities
  (collected during the engineering site
  visits). The purpose of collecting
  familiarization samples is to assess the
  effectiveness of the analytical methods
  identified  in the QAPjP for the analysis
  of the residuals of concern.
   Upon successful completion of the
  familiarization sampling and analysis
  effort, the Agency initiated record
  sampling and analysis of the consent
  decree wastes. The Agency sampled
  wastewaters and wastewater treatment
  sludges from twelve facilities. During a
  four-month period beginning in April of
  1997, the Agency collected 52 samples,
  excluding additional blanks and matrix
  spike/matrix spike duplicates(MS/MSD)
  collected for quality assurance
  purposes. Of these 52 samples, 41 were
 wastewater samples, and 11 were
 wastewater treatment sludge samples.
 2. RCRA Section 3007 Survey
   EPA developed an extensive
 questionnaire under the authority of
 Section 3007 of RCRA for distribution to
 the chlorinated aliphatics
 manufacturing industry. The purpose of
 the survey was to gather information
 about solid and hazardous waste
 generation and management practices in
 the U.S. chlorinated aliphatics
 manufacturing industry necessary to
 support the listing determination. The
 questionnaire covered topics such as
 chlorinated aliphatic product
 information, facility and unit process
 flow diagrams, process descriptions,
 residual generation and residual
 management profiles.
   The Agency distributed the survey in
 November of 1992 to 57 facilities and/
 or corporations identified as potential
 chlorinated aliphatics manufacturers
 from the most recent information
 available at the time. Of the 57 surveys
 distributed, completed surveys were
 received from 27 facilities. These
 facilities represent 20 companies that
 reported that they had manufactured
chlorinated aliphatics in 1991. The
remaining facilities notified EPA that
they had either stopped operations or

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 did not manufacture chlorinated
 aliphatic products.
   We also conducted an exhaustive
 engineering review of the submitted
 surveys for accuracy and completeness.
 Data from the survey responses was
 then entered into a data base known as
 the Chlorinated Aliphatics Industry
 Studies Data Base (ISDB). We conducted
 quality assurance reviews of the ISDB to
 identify any inappropriate entries and
 missing data links. The exhaustive
 engineering review of each facility's
 response resulted in follow-up letters
 and/or telephone calls to facility
 representatives seeking clarifications,
 corrections, and additional data where
 needed. The responses to these requests
 for clarification, along with additional
 information gathered during engineering
 site visits and familiarization and record
 sampling activities were entered into
 the data base.
   In 1996 we conducted a review of
 data collected previously, and re-
 contacted facility representatives to
 verify the status of chlorinated
 aliphatics manufacturing operations. In
 June of 1997, the Agency sent requests
 for updated data  (for calendar year
 1996J regarding consent decree wastes
 generated to each facility. We processed
 the data received from this request in
 the same manner as the original RCRA
 surveys, and entered the new
 information into the ISDB. Between
 1993 and 1996, two chlorinated
 aliphatics manufacturers ceased
 operations, resulting in a universe of 23
 chlorinated aliphatics manufacturing
 facilities owned and operated by 19
 different companies. Each of the 23
 current manufacturers of chlorinated
 aliphatics generate at least one
 wastestream identified in the consent
 decree. All 23 facilities generate at least
 one wastewater residual, while 14
 facilities reported that they generate
 wastewater treatment sludges.
 D. What Are the RJsks Associated With
 Management of Wastewaters and
 Wastewater Treatment Sludges From the
 Production of Chlorinated Aliphatic
 Chemicals?
  As discussed in Section III.A.2. of this
 preamble, EPA considers the Listing
 criteria set out in 40 CFR 261.11, as well
 as any other information relevant to the
 criteria, in making listing
 determinations. The criteria provided in
 40 CFR 261.11 include eleven factors for
 determining "substantial present or
 potential hazard to human health and
 the environment." Nine of these factors,
 as described generally below, are
 directly incorporated into EPA's
completion of a risk assessment for the
wastestreams of concern:
                          • Toxicity (§ 261.11 (a) (3) (i)) is
                        considered in developing the health
                        benchmarks used in the risk assessment
                        modeling.                    '
                          • Constituent concentrations and
                        waste quantities (§ § 261.11 (a) (3) (ii) and
                        261.11 (a) (3) (viii)) are used to define the
                        initial conditions for the risk evaluation.
                          • Potential to migrate, persistence,
                        degradation, and bioaccumulation of the
                        hazardous constituents and any
                        degradation products (261.11 (a) (3) (iii),
                        261.11(a)(3)(iv), 261.11(a)(3)(v), and
                        261.11 (a) (3) (vi)) are all considered in
                        the design of the fate and transport
                        models used to determine the
                        concentrations of the contaminants to
                        which individuals are exposed.
                          We consider two of the remaining
                        factors, plausible mismanagement and
                        other regulatory actions
                        (§ § 261.11 (a) (3) (vii) and 261.11 (a) (3) (x))
                        in establishing the waste management
                        scenario (s) modeled in the risk
                        assessment.
                          EPA conducted analyses of the risks
                        posed by wastewaters and wastewater
                        treatment sludges from the production
                        of chlorinated aliphatic chemicals to
                        assist in the determination of whether
                        the wastes meet the criteria for listing
                       set forth in 40 CFR 261.11 (a) (3). This
                       section (III.D.) discusses the human
                       health risk analyses and ecological risk
                       screening analyses EPA conducted to
                       support our proposed listing
                       determinations for chlorinated
                       aliphatics wastewaters (other than VCM-
                       A wastewaters), EDC/VCM wastewater
                       treatment sludges, and methyl chloride
                       wastewater treatment sludges. We
                       consider the risk analyses in developing
                       our listing decisions for each of the
                       wastestreams (described in Sections
                       III.E.l.a. for chlorinated aliphatics
                       wastewaters, III.E.2. for EDC/VCM
                       sludges, and III.E.4. for methyl chloride
                       sludges). The risk analyses we describe
                       in this section (III.D.) are presented in
                       detail in the Risk Assessment Technical
                       Background Document for the
                       Chlorinated Aliphatics Listing
                       Determination which is located in the
                       docket for today's proposed rule.
                        Because full risk analyses were not
                       necessary for VCM-A wastewaters,
                       VCM-A sludges, or allyl chloride
                       sludges, we discuss our assessment of
                       risks attributable to each of these wastes
                       in the same sections where we describe
                       our listing decisions for each of the
                       wastes, that is, Sections III.E.l.b., III.E.3,
                       III.E.5, respectively.
  1. What are the Risks for Potential
  Human'Receptors?
  a. What was EPA's Approach to
  Conducting the Human Health Risk
  Assessment?
    EPA's human health risk analyses for
  chlorinated aliphatics wastewaters and
  EDC/VCM and methyl chloride sludges
  provide estimates of the incremental
  human health risks resulting from
  exposure to contaminants detected in
  these wastes. The incremental human
  health risks are expressed as estimates
  of excess lifetime cancer risk for
  individuals ("receptors") who may be
  exposed to carcinogenic (cancer-
  causing) contaminants and hazard
  quotients (HQs) for those contaminants
  that produce noncancer health effects.
  Excess lifetime cancer risk is the
  incremental probability (chance) of an
  individual developing cancer over a
  lifetime as a result  of exposure to a
  carcinogen. A hazard quotient is the
  ratio of an individual's chronic daily
  dose of a noncarcinogen to an
  acceptable daily dose for chronic
 exposures to the noncarcinogen.
   EPA used two different methods of
 analysis to estimate risks. These
 methods are called "deterministic risk
 analysis" and "probabilistic risk
 analysis." A deterministic risk analysis
 produces a point estimate of risk or
 hazard for each receptor based on using
 a single value for each parameter in the
 analysis. A probabilistic analysis
 calculates risk or hazard by allowing
 some of the parameters to have more
 than one value, consequently producing
 a distribution of risk or hazard for each
 receptor. A parameter is any one of a
 number of inputs or variables (such as
 waste volume or distance between the
 waste management  unit and the
 receptor) required for the fate and .
 transport and exposure models and
 equations that EPA  uses to assess risk.
 (In some cases EPA treats multiple
 parameters as a single parameter for the
 purpose of conducting our analyses. We
 do this to prevent inadvertently
 combining parameters in our analyses in
 ways that are unrealistic. For example,
 EPA treats environmental setting
 [location] parameters such as climate,
 depth to groundwater, aquifer type as a
 single set of parameters. We believe
 that, for example, allowing the climate
 from one location to be paired with the
 depth to groundwater for another
 location could result in a scenario that
 would not occur in nature.)
  EPA conducts both "central
 tendency" and "high end" deterministic
risk assessments to attempt to quantify
the cancer risk or non-cancer hazard for
the "average" receptor in the population

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                                                                        46483
  (the central tendency risk) and the risk
  or hazard for individuals in small, but
  definable "high end" segments of the
  population (the high end risk). For
  central tendency deterministic risk
  analyses, we set all parameters at their
  central tendency values. For the
  chlorinated aliphatics risk assessments,
  the central  tendency values generally
  are either mean (average) or 50th
  percentile (median)  values.
    We use high end deterministic risk
  analysis to predict the risks and hazards
  for those individuals exposed at the
  upper range of the distribution of
  exposures. EPA's Guidance For Risk
  Characterization (EPA 1995)2 advises
  that "conceptually, high end exposure
  means exposure above about the 90th
  percentile of the population
  distribution, but not higher than the
  individual in the population who has
  the highest  exposure," and recommends
  that "* * * the assessor should
  approach estimating high end by
  identifying the most sensitive variables
  and using high end values for a subset
  of these variables,  leaving others at their
  central values." For the  chlorinated
  aliphatics high end deterministic risk
  analyses, EPA set two parameters at
  their high end. values (generally 90th
  percentile values), and set all other
  parameters at their central tendency
 values. We used a  "sensitivity analysis"
 to identify the two parameters that we
 set at high end. A sensitivity analysis is
 an iterative procedure in which an
 analysis is performed by alternately
 setting different parameters at high end
 to identify the parameters that most
 influence the analysis' outcome. EPA
 compares the different results generated
 by the sensitivity analysis and selects
 the two high end parameters to which
 the analysis was "most sensitive," that
 is, the two parameters that are expected
 to generate the greatest estimate of risk
 or hazard.
   EPA used probabilistic risk
 assessment to support the results of the
 deterministic risk analyses and to allow
 EPA to quantify individual risk at
 selected percentiles of the risk
 distribution (for example, 50th
 percentile, 90th percentile. 95th
 percentile). EPA conducted probabilistic
 risk analyses for those combinations of
 receptor, contaminant, and pathway for
 which risk or hazard estimated using a
 deterministic analysis exceeded the
 following criteria: a cancer risk of 1x10
 ~6or a hazard quotient of 1. In a
 probabilistic  analysis, each parameter
 may have more than one value. EPA
  2 EPA. 1995. Guidance for Risk Characterization.
U.S. Environmental Protection Agency Science
Policy Council. February.
  develops "probability density
  functions" (PDFs), distributions that
  describe the full range of values that the
  various input parameters may have.
  Some of the parameters in the
  probabilistic analysis are set as constant
  values because (1) there are insufficient
  data to develop a PDF; (2) EPA made
  assumptions to simplify the analysis in
  cases where such simplifications would
  improve the efficiency of the analysis
  without significantly affecting the
  results; (3) site-specific constants are
  available; or (4) the analysis has not
  been shown to be sensitive to the value
  of the parameter, that is, even if the
  parameter varies, the resulting risk
  estimate does not vary significantly. The
  Risk Assessment Technical Background
  Document for the Chlorinated
  Aliphatics Listing Determination
  describes the input parameters used in
  the probabilistic analysis. In the
  probabilistic analysis, risk is
  approximated through repetitive
  calculation of the fate and transport and
  exposure equations and models using
  input parameters randomly selected
  from the PDFs.  The result of the
  probabilistic analysis is a distribution of
  the risks or hazards for each of the
  receptors.
   The human health risk assessments
  that EPA conducted to support the
  chlorinated aliphatics listing
  determination included four primary
  tasks: (1) establishing that there are
  constituents in the wastes that are of
  concern to the Agency and that warrant
 analysis to determine their risk to
 human health; (2) establishing a
 scenario under which contaminants are
 released from a  waste management unit
 and subsequently are transported in the
 environment to  a human receptor; (3)
 estimating the concentrations of
 contaminants to which the receptor
 might be exposed; (4) quantifying the
 receptor's exposure to contaminants and
 the contaminants' toxicity to the
 receptor; and (5) describing the
 receptor's predicted risk. The following
 sections discuss how EPA completed
 each of these tasks for the risk
 assessments conducted to support the
 chlorinated aliphatics listing
 determination.

 b. How Did EPA Determine Which
 Waste Constituents and Waste Volumes
 Would Be Evaluated in the Risk
 Assessments?
  To support the chlorinated aliphatics
 listing determination, EPA collected and
 analyzed samples of wastewaters from
 the production of chlorinated aliphatic
chemicals, wastewater treatment
sludges from the production of EDC/
VCM, and wastewater treatment sludges
   from, the production of methyl chloride
   (see Section III.E of today's preamble, as
   well as the Background Document for
   Identification and Listing of Chlorinated
   Aliphatics Production Wastes, for
   further discussion of EPA's waste
   characterization efforts). We used the
   results of these waste analyses to
   establish the  "constituents of potential
   concern" (COPCs) in the wastes. We
   derived waste volume information from
   data provided by facilities in their
   RCRA Section 3007 questionnaire
  responses.
    EPA collected and analyzed 41
  samples of wastewaters generated from
  the production of chlorinated aliphatic
  chemicals. EPA collected six of these
  samples at the influent (or
  "headworks") of wastewater treatment
  systems that manage only wastewaters
  derived from the production of
  chlorinated aliphatic chemicals. We call
  these samples "dedicated" chlorinated
  aliphatics wastewater samples,3 and we
  chose to use these samples in our
  assessment of the risks and hazards
  attributable to the management of
  chlorinated aliphatic wastewaters. (The
  assessment of dedicated sample data
  allows us to evaluate without question
  what risks are attributable to the wastes
  of concern to the Agency.) Because we
  used  analytical data for dedicated
  chlorinated aliphatics wastewater
  samples in our analysis, we also used
  dedicated chlorinated aliphatic
  wastewater volumes in our analysis. We
  identified eight wastewater volumes
  that represent  the volumes of dedicated
 chlorinated aliphatics wastewaters
 discharged to the headworks of
 chlorinated aliphatics facility
 wastewater treatment systems.
   EPA collected and analyzed seven
 samples of nonhazardous EDC/VCM
 sludge. (Some sludges generated by this
 industry already are designated as
 hazardous because they include
 material derived from wastes that EPA
 previously listed as hazardous waste.)
 Four were samples of sludges that were
 derived from wastewater treatment
 systems that manage only EDC/VCM
 process wastewaters. These samples are
 "dedicated" EDC/VCM sludge samples.
 Three were samples of sludges that
 result  from the  treatment of EDC/VCM
 process wastewaters combined with
 wastewaters from non-EDC/VCM
 processes and sources. EPA chose to use
 only the dedicated EDC/VCM sample
 data in our analysis. Because we used
  3 "Dedicated" chlorinated aliphatic wastewaters
are those that are comprised only of chlorinated
aliphatics process wastewaters, that is, wastewaters
generated from the production of the chlorinated
aliphatic chemicals of concern to this listing
determination.

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  analytical data for dedicated EDC/VCM
  sludge samples in our analysis, we also
  used "dedicated" EDC/VCM sludge
  volumes. EPA divided the volume of
  wastewater attributable to EDC/VCM
  processes by the total volume of
  wastewater influent, and applied the
  resultant ratio to the total sludge
  volumes to obtain the volume of
  wastewater treatment sludge attributable
  to EDC/VCM processes (that is, the
  "dedicated " EDC/VCM sludge volume).
   The methyl chloride sludge, generated
  by only one facility, results from
  treatment of the combined wastewaters
  from the facility's methyl chloride
  production process and other facility
  processes and sources. The facility
  reports that approximately 18 percent of
  the wastewater that generates the sludge
  is from the methyl chloride process. The
  remainder of the wastewater is from
.  pther processes. Because the sludge, as
  generated, is not dedicated, and there is
  no means to obtain a dedicated sample
  of the methyl chloride sludge, we
  conducted our risk assessment using the
  sample data for the nondedicated
  methyl chloride sludge sample, and,
  comparably, the nondedicated (total)
  methyl chloride sludge volume.
   Using the results ofthe analysis of the
  waste samples, EPA developed a list of
  "chemicals of potential concern"
  (COPCs) for the chlorinated aliphatics
  wastewaters, EDC/VCM sludges, and
  methyl chloride sludges. The COPCs are
  the constituents which were the subject
  of EPA's risk assessment. EPA
  developed the COPC lists by taking the
  complete list of detected constituents in
  the wastes and eliminating constituents
  from the list that occurred at
  concentrations clearly below levels of
  concern, based on screening analyses
 developed to maximize risk estimates.
 For chlorinated aliphatics wastewaters
 and EDC/VCM sludges, EPA also
 eliminated constituents when a
 constituent was detected in only one of
 the samples and the concentration of the
 constituent in the one sample was
 qualified  with the "J" qualifier.
 indicating that the constituent was
 detected below the quantitation limit
 and the reported value was estimated.
 Specifically, the laboratory detected 69
 constituents in chlorinated aliphatics
 wastewater samples of which we
 eliminated 28; 53 constituents in EDC/
 VCM sludges of which we eliminated
 16; and 19 constituents in methyl
 chloride sludges of which we
 eliminated 11.
   Six polychlorinated dibenzodioxin
 ("dioxin") congeners and ten
 polychlorinated dibenzofuran ("furan")
 congeners were among the constituents
 detected in samples ofthe chlorinated
                        aliphatics wastewaters, EDC/VCM
                        sludges, and methyl chloride sludges
                        and evaluated in the risk assessment.
                        EPA classifies the furan congeners and
                        certain polychlorinated biphenyl (PCS)
                        congeners as "dioxin-like compounds"
                        because of their structural similarity to
                        the dioxins (EPA 1994a4). In today's
                        preamble we use the term "dioxins" to
                        represent both the dioxin and furan
                        congeners. Our use of the term
                        "dioxins" does not refer to dioxin-like
                        PCBs because we did not analyze for
                        PCBs in our waste samples from the
                        chlorinated aliphatics industry since we
                        do not expect PCBs to be constituents of
                        the chlorinated aliphatics wastes that
                        are the subject of today's listing
                        determination.

                        c. What Exposure Scenarios Did EPA
                       Evaluate?
                         Prior to conducting the risk
                       assessments, EPA had to establish that
                       there is a plausible scenario under
                       which a receptor might  be exposed to
                       contaminants in the wastewaters and
                       sludges. Establishing this scenario
                       required that EPA determine:
                         • How the waste is managed or is
                       likely to be managed;
                         • How contaminants could be
                       released from the waste  management
                       unit;
                         • How contaminants could be
                       transported in the environment  to a
                       point of contact with a receptor; and
                         • How a receptor could be exposed to
                       the contaminants.
                         One respondent to EPA's §3007
                       questionnaire reported that they
                       discharge a portion of their
                       nonhazardous chlorinated aliphatics
                       wastewaters to nonhazardous
                       underground injection wells. Section
                       III.E.l.a.i. discusses EPA's evaluation of
                       the underground injection waste
                       management scenario. Twenty-three
                       respondents reported that they manage
                       their nonhazardous or exempt
                       chlorinated aliphatics wastewaters in
                       tanks. Because management of
                       wastewaters in tanks is the dominant
                       wastewater management practice in the
                       chlorinated aliphatics industry, EPA
                       chose to evaluate tanks in our risk
                       assessment for chlorinated aliphatics
                       wastewaters. For reasons discussed in
                       III.E.l.a.i., EPA chose to evaluate risks
                       attributable to management of
                       chlorinated aliphatics wastewaters in
                      uncovered aerated biological treatment
                      tanks.
                        One respondent to EPA's §3007
                      questionnaire reported that they  manage
                       "EPA. 1994a. Estimating Exposure to Dioxin-Like
                      Compounds. Volume I: Executive Summary.
                      Review Draft. EPA/600/6-88/005Ca. Office of
                      Research and Development. June.
  their EDC/VCM wastewater treatment
  sludges in an onsite land treatment unit.
  All other respondents reported that
  nonhazardous EDC/VCM sludges are
  managed in landfills. Eight facilities
  send EDC/VCM sludges to offsite
  nonhazardous waste-landfills, two
  facilities manage EDC/VCM sludge in
  onsite nonhazardous industrial waste
  landfills, and one facility manages their
  nonhazardous EDC/VCM sludge in an
  onsite hazardous waste landfill (see
  section III.E.2.a. in today's preamble for
  a description of current methods for
  managing EDC/VCM sludges). For this
  assessment, EPA evaluated the risks
  associated with management of EDC/
  VCM sludges in unlined municipal
  landfills and in a land treatment unit.
  Because the only facility that generates
  methyl chloride sludges manages them
  in an onsite nonhazardous industrial
 waste landfill,  EPA evaluated this
 management scenario in our risk
 assessment for methyl  chloride sludges.
 The Risk Assessment Technical
 Background Document for the
 Chlorinated Aliphatics Listing
 Determination  provides a complete
 discussion of the parameters that define
 the characteristics of the waste
 management units.
   EPA determined that releases from all
 of the waste management units (tank,
 land treatment unit, and landfill) could
 occur through release of vapor
 emissions to the air. In addition, for the
 land treatment unit and the landfill,
 EPA  determined that releases could
 occur through leaching ofthe waste into
 the subsurface. We assumed that the
 chlorinated aliphatics industry's tanks
 retain sufficient structural integrity to
 prevent wastewater releases to the
 subsurface (and therefore to
 groundwater), and that overflow and
 spill controls prevent wastewater
 releases to the ground surface. For the
 land treatment unit, releases also could
 occur through release of particulate
 emissions to the air and runoff and
 erosion of waste from the unit. EPA
 assumed that wastewater would entrain
 any particulate  matter such that
 particulates would not be released from
 the tanks. EPA did not evaluate
 particulate emissions from the landfills
 because the moisture content of the
 sludges (41 to 74 percent moisture)
 would prevent generation and release of
 particulates to the air in the time
 between placement of the waste in the
 landfill and application of daily cover or
 a new day's waste addition. EPA also
 assumed that runon/runoff controls
would prevent releases  from the
landfills due to erosion  and  runoff.
  EPA also evaluated the mechanisms
and pathways by which contaminants   .

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                 Federal Register/Vol. 64, No. 164/Wednesday, August  25,  1999/Proposed Rules
                                                                        46485
  might be transported to the points
  where receptors are exposed. The
  mechanisms and pathways we
  evaluated are as follows:
    •  Eroded waste can be transported by
  runoff and deposited onto the soil and
  into surface water bodies.
    •  Leachate can migrate through the
  unsaturated5 zone to the saturated6
  zone, where contaminants are
  transported in groundwater to drinking
  water wells and to points of discharge
  to surface water bodies.
    •  Vapor emissions can remain
  dispersed in the air, or can  be deposited
  through wet and dry deposition.
  Specifically, EPA models:
    •  The concentration of vapor phase
  contaminants in air,
    •  The diffusion of vapor  phase
  contaminants into plants,
    • The diffusion of vapor  phase
  contaminants into surface water,
   • Wet deposition of vapors onto soils
  and surface water (for example, due to
  wash-out [scavenging] by precipitation).
   • Dry deposition of vapors onto soils
  (for example, due to density).
   • Although we  do not evaluate wet
 and dry deposition of vapors onto
 plants, we do assume that wet and dry
 deposition of vapors onto soils increase
 the contaminant concentrations in the
 soil and result in additional uptake of
 contaminants into plants via soil-to-
 plant uptake.
   • Particulate emissions can remain
 dispersed in the air or be deposited
 through wet deposition (in
 precipitation) or dry deposition (particle
 settling). We assume that particulates
 may be deposited  onto soil and surface
 water through both wet and  dry
 deposition, and onto plants  through dry
 deposition.
   Human receptors indirectly may come
 into contact with vapors that diffuse
 into vegetation, particulates  that are
 deposited on vegetation, or
 contaminants that are taken  up by
 vegetation from the soil through
 exposure to contaminated home-grown
 fruits and vegetables, as well as
 exposure to contaminated beef and
 dairy products derived from  cattle
 which have ingested contaminated
 forage, silage, grain, and surface soil.
 Receptors that ingest fish also indirectly
 may come into contact with
 contaminants in air-borne vapors and
 particulates (through vapor diffusion
 into surface water, vapor deposition
 onto surface water, and particulate
  deposition onto surface water),
  contaminated groundwater (through
  groundwater discharge into surface
  water), and runoff and eroded soil that
  enter surface water.
    EPA determined that the following
  receptors reasonably represent the types
  of individuals that could be exposed to
  contaminants in chlorinated aliphatics
  wastes, and were the receptors
  evaluated in our risk analyses:
  • an adult resident
 , • the child of a resident
  • a home gardener
  • a farmer
  • the child of a farmer
  • a fisher
  The following sections describe briefly
  EPA's primary assumptions regarding
  the characteristics and activities of each
  of the receptor types, and the routes by
  which each receptor is exposed.
    Adult Resident and Child of
  Resident—We assume that an adult and
  child reside near the waste management
  unit. The residential receptors inhale
 vapors and particulate matter that are
 dispersed in the ambient air. EPA
 assumes that household water is
 supplied to the  residential receptors by
 a domestic groundwater well that is
 located near their home. The adult
 resident and_child of the resident drink
 water that comes from the well. We
 assume that the adult resident inhales
 vapors that are emitted from the water
 that they use in their house (for
 example, during showering), and that
 the adult resident's skin also is exposed
 to groundwater when he/she bathes.
 The residential receptors do not ingest
 foods that are grown in the vicinity of
 their home, however they do
 incidentally ingest surface soil from
 their yard.
   Home Gardener—We assume that the
 residential receptor may have a home
 garden. The home gardener grows fruit,
 exposed vegetables (vegetables with
 edible parts that are exposed at land
 surface), and root vegetables.
 Approximately 23 percent of the
 exposed vegetables, 11 percent of the
 root vegetables, and  12 percent of the
 fruits eaten by the gardener are grown
 in his/her garden (EPA 1997a, Table 13-
 71)7.  The gardener's other
 characteristics and activities are the
 same  as those of the adult resident.
  Fisher—We assume that the
 residential receptor may be a
recreational angler. Approximately 32
percent of the fish eaten by the fisher
  5 The unsaturated (vadose) zone is a subsurface
zone in which the pore spaces contain both water
and air.
  6 The saturated zone is a subsurface zone in
which all pore spaces are full of water.
  7 EPA. 1997a. Exposure Factors Handbook.
Volumes I. II, and III. Office of Research and
Development, Washington, D.C., EPA/600/P-95/
002Fa, b, c. August 1997; www.epa.gov/ordntrnt/
ord/webpubs/exposure/index.html.
  are from a stream located near the waste
  management unit (EPA 1997a, Table 13-
  71). The fisher's other characteristics
  and activities are the same as those of
  the adult resident.
    Adult Farmer and Child of Farmer—
  We assume that a farmer raises fruits,
  exposed vegetables, root vegetables, beef
  cattle, and dairy cattle in an agricultural
  field located near the waste
  management unit. Approximately 42
  percent of the exposed vegetables, 17
 .percent of the root vegetables, 33
  percent of the fruits, 49 percent of the
  beef, and 25 percent of the dairy
  products eaten by the farmer and the
  child of the farmer are grown/raised on
  the farmer's agricultural field (EPA
  1997a, Table 13-71), We assume that
  the farmer incidentally ingests soil from
  the agricultural field, and that the child
  of the farmer incidentally ingests soil
  from his/her yard. The farmer's and
  child's exposure to groundwater via
 ingestion, inhalation, and dermal
 contact are the same as that for the adult
 resident and child of the resident.
   EPA establishes the locations of
 receptors relative to waste management
 units based on information obtained
 from national surveys. Exposure to
 groundwater occurs through the use of
 water from drinking water wells,  and
 exposure via nongroundwater pathways
 occurs through runoff/erosion and
 releases to air. Therefore, "distance to
 receptor" for groundwater exposure
 pathways actually is the distance to the
 drinking water well that the receptor is
 using (the "receptor well"). "Distance to
 receptor" for nongroundwater pathways
 is the distance to the residence where
 the receptor is inhaling air or contacting
 soil, the distance to the garden where
 the receptor is growing fruits and
 vegetables, or the distance to the field
 where the receptor is growing crops or
 raising livestock. Consequently, EPA
 uses different databases to establish
 "distance to receptor," depending on
 whether we are evaluating a
 groundwater or a nongroundwater
 pathway.
  For analysis of the nongroundwater
 pathway (air pathways and erosion/
 runoff) risks in the deterministic
 analysis we assume that the receptors
 live either 75 meters (m) (high end) or
 300 m (central tendency) from the waste
 management unit. The distance of 250
 feet (ft) (approximately 75 m) is based
 on the actual measured distance to the
 nearest resident for the worst-case
 facility evaluated in the risk assessment
 conducted to support the "Hazardous
 Waste Treatment, Storage, and Disposal
 Facilities—Organic Air Emissions
Standards for Process Vents and
Equipment Leaks Final Rule" (55 FR

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  46486
Federal Register/Vol. 64. No.  164/Wednesday,  August 25, 1999/Proposed Rules
  25454), and was used as distance to the
  nearest resident for that rulemaking. In
  the same risk assessment, EPA
  identified the receptor distance of 1000
  ft (approximately 300 m) as the median
  distance in a random sample of
  distances to the nearest residence. For
  the probabilistic analysis, we assume
  the receptors live either 50, 75, 100, 200,
  300, 500, or 1000 rn from the waste
  management unit. For air pathway
  analyses, we always assume that the
  receptors (including cattle) are located
  along the centerline of the area most
  greatly impacted by air releases from the
  waste management units. However, at
  distances of a few hundred meters from
  the waste management unit, the air
  concentrations within about a 100 meter
  lateral distance do not vary appreciably.
   For deterministic analyses we assume
  that a receptor well is located 102 m
  (high end) or 430 m (central tendency)
• from the waste management unit,, and
  that the receptor well  is located on
  centerline of the contaminant plume
  (high end) or halfway  between the
  centerline and the edge of the
  contaminant plume (central tendency).
 The 102 m distances is the 10th
  percentile value in the distribution of
 distances derived from EPA's 1988
 survey of Solid Waste  (Municipal)
 Landfill Facilities (DPRA 19938). The
 430 m value is the 50th percentile value
 in that same distribution. For the Monte
 Carlo analysis, the distance from the
 waste management unit to the receptor
 well is based on the complete
 distribution of distances to receptor well
 reported by the survey respondents, and
 ranges from 0.02 m (the location of the
 closest reported well was 0 m) to 1604
 m (the maximum distance for which
 EPA requested receptor well
 Information was 1 mile). For the Monte
 Carlo analysis we assume that the
 receptor well is located anywhere
 within the contaminant plume.
   The Risk Assessment Technical
 Background Document for the
 Chlorinated Aliphatics Listing
 Determination provides a complete
 discussion of the values of additional
 parameters that define  the
 characteristics of each receptor, such as
 the amounts of contaminated food and
 water they ingest, their inhalation rates,
 and how long they live near the waste
 management unit.
                        d. How Did EPA Predict What
                        Contaminant Concentrations Are at the
                        Points Where Receptors Are Exposed?
                          EPA conducts contaminant fate and
                        transport modeling and indirect
                        exposure modeling to determine what
                        the concentrations of contaminants will
                        be in the media (for example,
                        groundwater, air, soil, food items) that
                        the receptor comes into contact with.
                        These concentrations are called
                        "exposure point concentrations"  (that
                        is, they are the contaminant
                        concentrations at the point where the
                        receptor is exposed to the
                        contaminants). There are a number of
                        computer-based models and sets of
                        equations that EPA uses to predict
                        exposure point concentrations. In the
                        following sections we briefly discuss
                        these models and equations and their
                        application in the risk analyses.
                        i. Partitioning Model
                         For the landfill and the land treatment
                        unit, EPA uses a series of "partitioning"
                        equations to determine how much
                        contaminant mass is retained in the
                        waste management unit and how much
                        is released into the environment. These
                        equations are based upon equations
                        presented in a series of articles by Jury
                        et al. (Jury et al. 1983, 1984, and 19909).
                        EPA used the partitioning equations to
                        estimate the mass of a contaminant that
                       will be lost from the land treatment unit
                       due to volatilization into the air,
                       contaminant leaching into the
                       subsurface, runoff from the land
                       treatment unit, and degradation. For the
                       landfill scenarios, EPA used the
                       partitioning equations to determine how
                       much of the contaminant mass would be
                       lost due to volatilization into the air;
                       EPA assumed that the remainder of the
                       mass would be available to leach into
                       the subsurface. We assumed that
                       volatilization losses could occur prior to
                       the landfill being covered with daily
                       cover or daily waste addition, through
                       the daily cover or daily waste addition,
                       and through the cap that is placed on
                       the landfill after closure. For the
                       landfill, we used toxicity characteristic
                       leaching procedure (TCLP) analytical
                       results (rather than the partitioning
                       equations) as the predictor of leachate
  • DPRA, 1993. Parameter Values for Developing
NiUonwlde Regulations with the EPA's Composite
Model for Landfills (EPACML). EPA Contract
Number 68-WO-0029. July.
                        "Jury. W.A., W.F. Spencer, and W. J. Farmer.
                       1983. Behavior assessment model for trace organics
                       in soil: i. model description. J. Environ. Qual.
                       12(4):558-564.
                        Jury, W.A.. W. J. Farmer, and W.F. Spencer. 1984.
                       Behavior assessment model for trace organics in
                       soil: ii. chemical classification and parameter
                       sensitivity. J. Environ. Qual. 13(4):567-572.
                        Jury, W.A., D. Russo, G. Streile, and H.E. Abd.
                       1990. Evaluation of volatilization by organic
                      chemicals residing below the soil surface. Water
                      Resources Research. 26(1):13-20.
  concentration. The TCLP is an
  analytical procedure that "leaches" a
  waste sample in a way that mimics the
  leaching of waste in a municipal
  landfill. Thus, TCLP results are a proxy
  for the concentrations of contaminants
  that would be generafed in leachate if
  the waste were placed in a municipal
  landfill.

  ii. Tank Emissions Model

    EPA modeled emissions from aerated
  biological wastewater treatment tanks
  using the CHEMDAT8 model (EPA
  1994b ]°). We used the emissions
  estimates in conjunction with the air
  dispersion modeling results (see Section
  D.l.d.iii) to estimate constituent-specific
  air concentrations and deposition rates.
  CHEMDAT8 accounts for most of the
  competing removal pathways that might
  limit air emissions, including
  adsorption, biodegradation, and
  hydrolysis.  Chemicals that sorb to solids
  or decompose due to either
  biodegradation or hydrolysis have lower
  potential for emission to the air.
  CHEMDAT8 is considered to provide
  reasonable to slightly high estimates of
  air emissions.
    CHEMDAT8 requires that the user
  specify parameters relating to tank
  characteristics, waste characteristics,
  contaminant physical and chemical
  properties, and location-specific
  meteorological conditions (for example,
  windspeed and temperature). The tank
  characterization data required by the
 model include both tank physical
 parameters (for example, tank
 dimensions) and tank operating
 parameters (for example, the number of
 aerators in the tank). In the absence of
 site-specific data, we developed tank
 dimensions based on facility-reported
 wastewater generation rates, an assumed
 wastewater depth in the tank of 15 feet,
 and a retention time in the tank of two
 days. We selected operating parameters
 that we believe represent typical
 operating conditions of an aerated tank.
 The Risk Assessment Technical
 Background Document for the
 Chlorinated Aliphatics Listing
 Determination provides a complete list
 of the parameters used in the
 CHEMDAT8 model.

 iii. Air Dispersion and Deposition
 Model

  We used EPA's Industrial Source
 Complex Short Term model  (version 3;
  '°EPA. 1994b. CHEMDAT8 User's Guide, EPA-
453/C-94-080B. Office of Air Quality Planning and
Standards, US Environmental Protection Agency,
Research Triangle Park, NC, November. This model
is publicly available from EPA's Web page at http:/
/www.epa.gov/ttn/chief/software.html.

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                 Federal  Register/Vol. 64, No. 16,4/Wednesday, August 25,  1999/Proposed Rules
                                                                         46487
  ISCST3 '') to estimate the dispersion
  and deposition of vapors emitted from
  the wastewater treatment tank, the
  municipal landfill, the onsite industrial
  landfill, and the land treatment unit.
  EPA also used ISCST3 to estimate the"
  dispersion and deposition of particulate
  emissions from the land treatment unit.
  For the land treatment unit, EPA used
  equations documented in EPA's
  "Compilation of Air Pollutant Emission
  Factors (AP-42)" (EPA 1985) ™ to
  estimate particulate emissions resulting
  from wind erosion and tilling activities.
  Vapor emissions from the landfill and
  the land treatment unit were estimated
  using the partitioning models discussed
  in Section III.D.l.d.i. Vapor emissions
  from the wastewater treatment tank
  were estimated using the CHEMDAT8
  model discussed in Section III.D. 1 .d.ii.
  ISCST3 was used to estimate the air
  concentration of vapors,  wet deposition
  of vapors, the air concentration of
  particulates, wet deposition of
 particulates, and dry deposition of
 particulates. We calculate dry
 deposition of vapors using the air
 concentration of vapors and a
 contaminant deposition velocity.
 iv. Overland Transport Model
   The Universal Soil Loss Equation
 (USLE) is an erosion model originally
 designed to estimate long-term average
 soil erosion losses to a nearby surface
 water body from an agricultural field
 having uniform slope, soil type,
 vegetative cover, and erosion-control
 practices. We used a modified form of
 the USLE to estimate the  mass of soil
 lost per year per unit area from the land
 treatment unit and deposited directly
 onto the adjacent receptor site
 (agricultural field, residential lot, home
 garden) and into a nearby stream.
   Because the basic USLE equation
 estimates only soil erosion to surface
 water bodies, EPA assumes the receptor
 location is located between the land
 treatment unit and the surface water
  " EPA. 1995. User's Guide for the Industrial
Source Complex (ISC3) Dispersion Models (Draft)
(Revised). Volume I. EPA-454/B-95-003a. Office of
Air Quality Planning and Standards, Emissions,
Monitoring and Analysis Division. Research
Triangle Park, NC. The ISCST3 model and
meteorological preprocessor. PCRAMMET. and
related user's guides can be accessed and
downloaded through the Internet from the Support
Center for Regulatory Air Models (SCRAM) web
page (http://www.epa.gov/scram001). The SCRAM
is part of EPA's Office of Air Quality Planning and
Standards (OAQPS) Technology Transfer Network
OTN).
  12EPA. 1985. Compilation of Air Pollutant
Emission Factors. AP-42, Fifth Edition. Volume I:
Stationary Point and Area Sources. Office of Air
Quality Planning and Standards, Emissions
Inventory Group, Research Triangle Park. NC. AP-
42 can be downloaded through the Internet at http:/
/www.epa.gov/ttn/chief/ap42.html.
  body. The area including the land
  treatment unit, the receptor site, and the
  intervening area is considered for the
  purposes of the analysis to be an
  independent, discrete drainage subbasin
  that is at steady-state. We estimate the
  soil erosion load from the subbasin to
  the surface water body using a distance-
  based sediment delivery ratio, and
  consider that the sediment not reaching
  the surface water body is deposited
  evenly over the area of the subbasin.
  Using mass balance equations, EPA
  estimates contaminant contributions to
  the surface water body and the receptor
  soil. "Mass balance equations" are
  equations that honor the law of
  conservation of mass, that is, the mass
  of a contaminant that is present at the
  beginning of the analysis (for example,
  the mass of a contaminant in a waste
  placed in a waste management unit) is
  equal to  the mass of the contaminant
  present at the end of the analysis. Even
  though at the end of the analysis the
  contaminant mass may be partitioned
  into a number of environmental
  "compartments" (for example, the waste
  management unit, the soil, and the
 surface water body), there is in total no
 more or no less mass than was present
 at the start of the analysis.
   Contaminated particles are
 transported from the land treatment unit
 to receptor sites via air deposition as
 well as runoff/erosion. We applied mass
 balance for each area of interest (for
 example, buffer area between source
 and receptor site, receptor site, or
 surrounding area). Consequently, the
 respective air deposition value for each
 area of interest is included in the
 evaluation of the mass balance. We
 considered that the air deposition over
 the entire subbasin area is uniform and
 equal to the air deposition modeled for
 the receptor site.
 v. Groundwater Model
   We used EPA's Composite Model for
 Leachate  Migration with Transformation
 Products  (EPACMTP; EPA 1996a,
 1996b,  1996c, 1997 o) to model the
 subsurface fate and transport of
  13 EPA. 1996a. EPA's Composite Model for
Leachate Migration with Transformation Products
(EPACMTP) Background Document. Office of Solid
Waste. Washington, DC.
  EPA. 1996b. EPA's Composite Model for Leachate
Migration with Transformation Products
(EPACMTP) Background Document for the Finite
Source Methodology. Office of Solid Waste,
Washington, DC.
  EPA. 1996c. EPA's Composite Model for Leachate
Migration with Transformation Products
(EPACMTP) Background Document for Metals.
Office of Solid Waste, Washington, DC.
  EPA. 1997. EPA's Composite Model for Leachate
Migration with Transformation Products
(EPACMTP) .User's Guide. Office of Solid Waste,
Washington, DC.
  contaminants that leach from the waste
  management units (the land treatment
  unit or the landfill) and migrate to a
  residential drinking water well or
  discharge from groundwater to surface
  water.
    Precipitation that migrates through
  the waste management unit generates
  leachate, which infiltrates the bottom of
  the waste management unit and
  migrates into the unsaturated zone. The
  contaminants dissolved in the leachate
  subsequently are transported in the
  aqueous phase through the unsaturated
  zone to the underlying saturated zone
  and then downgradient to a receptor
  (drinking water) well or surface water
  body located at a specified distance
  from the boundary of the waste
  management unit. EPACMTP accounts
  for the following processes affecting
  contaminant fate and transport:
  advection, hydrodynamic dispersion,
  equilibrium linear or nonlinear sorption
  by the soil and aquifer solids (both in
  the unsaturated and saturated zones),
  and contaminant hydrolysis. In the
  event that the hydrolysis daughter
  products are toxic and their  chemical
 properties are known, the model also
 accounts for the formation and
 subsequent fate and transport of the
 daughter products.
   The landfill analysis employed two
 simplifying assumptions. First, we
 assumed that contaminant leaching
 from the landfill does not occur until
 after the landfill closes (that  is, after 30
 years). EPA made this assumption
 because of complexities associated with
 linking the output of the landfill
 partitioning equations (discussed in
 Section III.D.l.d.i.) and the groundwater
 model, EPACMTP. Second, we assumed
 that there are no contaminant losses due
 to mechanisms other than leaching after
 the landfill has been closed (that is, after
 30 years). This effectively over-estimates
 the total mass of volatile contaminants
 that would leach to groundwater
 because it does not allow contaminant
 loss due to volatilization from the
 landfill to deplete the total contaminant
 mass available for leaching from the
 landfill in the years after closure. EPA
 determined that if volatile constituents
 caused significant risk via the
 groundwater pathway, we would have
 to re-evaluate our methodology for
 conducting the landfill analysis. This
 situation did not occur.
 vi. Surface Water Model
  EPA assumed that fish are exposed to
waste constituents in surface  water.
Specifically, we assumed that fish are
exposed to contaminants dissolved in
the water column, contaminants sorbed
to suspended solids in the water

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  46488
Federal Register/Vol. 64, No.  164/Wednesday, August 25,  1999/Proposed  Rules
  column, and contaminants associated
  with the bed sediment in the surface
  water body. The method used to
  estimate how management of
  chlorinated aliphatics wastewaters and
  wastewater treatment sludges impacts
  surface water is based on the
  methodology presented in Addendum to
  Methodology for Assessing Health Risks
  Associated with Indirect Exposure to
  Combustor Emissions (EPA 1993) '4. The
  model accounts for six ways in which
  contaminants may enter the surface
  water body: (1) contaminants may be
  sorbed to eroded soils that enter the
  surface water body, (2)  contaminants
  may be dissolved in runoff that enters
  the surface water body, (3) contaminants
  may be bound to airborne particles that
  are deposited on the surface water body,
  (4) vapor phase contaminants in air may
  be deposited on the surface water body
  in precipitation (that is, wet deposition
  of vapor phase contaminants), (5)  vapor
  phase contaminants in air may enter the
  surface water body through direct
  diffusion from the air, and (6)
  contaminants in groundwater may
  discharge into the surface water body.
  The model also accounts for processes
  that remove contaminants from the
  surface water body. These include: (1)
  volatilization of contaminants that are
  dissolved in surface water and (2)  burial
  of contaminants in the sediment at the
  bottom of the surface water body. The
  model assumes that the impact to the
  water body is uniform, which is more
 realistic for smaller surface water bodies
  than for larger ones. The model
 estimates the concentrations of
 contaminants in the water column and
 bed sediment. We used the water
 column or bed sediment concentrations
 and bioconcentration factors (BCFs),
 bioaccumulation factors (BAFs), or
 biota-sediment accumulation factors
 (BSAFs) to estimate contaminant
 concentrations in fish tissue.
 vli, Indirect Exposure Equations
   EPA uses a series of "indirect
 exposure equations" to quantify the
 concentrations of contaminants that
 pass indirectly from contaminated
 environmental media to the receptor.
 For example, contaminants that are
 transported in air may be deposited on
 plants or onto the soil where they may
 accumulate in forage, grain, silage or
 soil that is consumed by beef cattle and
 dairy cattle. Individuals may then ingest
 contaminated beef and dairy products.
 Similarly, contaminants may be
                         transported in groundwater to domestic
                         groundwater wells where the
                         groundwater is extracted and used for
                         showering. The water vapor generated
                         in the shower may be inhaled by the
                         receptor. The indirect exposure
                         equations allow EPA to calculate
                         exposure point concentrations for these
                         pathways and routes of exposure. The
                         indirect exposure equations used by
                         EPA to conduct the chlorinated
                         aliphatic wastewater, EDC/VCM sludge,
                         and methyl chloride sludge risk
                         assessments are presented in the Risk
                        Assessment Technical Background
                        Document for the Chlorinated
                        Aliphatics Listing Determination.
                        e. How Did EPA Quantify Contaminant
                        Exposure and Toxicity?
                          Exposure is the condition that occurs
                        when a contaminant comes into contact
                        with the outer boundary of the body,
                        such as the skin, mouth and nostrils.
                        Once EPA establishes the
                        concentrations of contaminants at the
                        points of exposure, EPA can estimate
                        the magnitude of each receptor's
                        exposure, or the contaminant dose.  Dose
                        is the amount of the contaminant that
                        crosses the outer boundary of the body
                        and is available for absorption at
                        internal exchange boundaries  (lungs,
                        gut. skin; EPA 1992IS). For example, for
                        exposure to a carcinogen through
                        ingestion of contaminated drinking
                        water, dose is a function of the
                        concentration of the contaminant in
                        drinking water (the exposure point
                        concentration), as well as certain
                        "exposure factors," such as how much
                        drinking water the receptor consumes
                        each day (the intake rate), the number
                        of years the receptor is exposed to
                        contaminated drinking water (the
                        exposure duration), how often  the
                       receptor is exposed to contaminated
                       drinking water (the exposure
                       frequency), the body weight of the
                       receptor, and the period of time over
                       which the dose is averaged.
                         EPA's primary source of exposure
                       factors is the "Exposure Factors
                       Handbook"published by EPA in August
                       1997 (EPA 1997a>6). For probabilistic
                       risk analyses,  EPA used the
                       distributions of exposure factor values
                       provided in the Exposure Factors
                       Handbook to develop PDFs for exposure
                       factors. The one situation where EPA
                       does not develop an expression of dose
  is the case where we use Reference
  Concentrations (RfCs) " to estimate
  noncancer hazard for the inhalation
  exposure route. In this situation, EPA
  calculates noncancer hazard from
  concentration of the contaminant in air
  and the RfC, without considering
  exposure factors (inhalation rate, body
  weight) other than those inherent in the
  RfC.
    We express the toxicity of
  contaminants as health benchmarks.
  Health benchmarks  include cancer slope
  factors (CSFs, EPA's measure of cancer
  potency)'8 for oral exposure
  carcinogenic contaminants; reference
  doses (RfDs, EPA's acceptable
  contaminant dose via ingestion) >» for
  oral exposure to noncarcinogenic
  contaminants; inhalation CSFs for
  inhalation exposure to carcinogenic
  contaminants; and RfCs for inhalation
  exposure to noncarcinogenic
  contaminants. EPA derived inhalation
  CSFs from Unit Risk Factors  (URFs) for
  inhalation exposure  to carcinogens. EPA
  uses Toxicity Equivalency Factors
  (TEFs) to express the toxicity of specific
  dioxin congeners in  terms of the toxicity
  of 2,3,7,8-tetrachlorodibenzo-p-dioxin
  (2,3,7,8-TCDD) (see  Section III. D.l.g.ii.
  for an explanation of TEFs). Health
  benchmark values are available from a
  number of sources. For the chlorinated
  aliphatics wastewater, EDC/VCM
 sludge,  and methyl chloride sludge risk
 assessments, EPA established an order
 of preference for the  sources of health
 benchmarks. The order of preference is
 as follows (from most preferred to least
 preferred):  (1) the Integrated Risk
 Information System (IRIS) online
 database of verified health benchmarks
 (http://www.epa.gov/iris/subst/
 index.html) 2°; (2) the Health Effects
 Assessment Summary Tables  (HEAST;
  14 EPA, 1993, Addendum to Methodology for
Assessing Health Risks Associated with Indirect
Exposure to Combustor Emissions. EPA/600/AP-
93003. Office of Health and Environmental
Assessment. Washington. DC.
                        is 57 FR 22888. Final Guidelines for Exposure
                      Assessment. U.S. Environmental Protection Agency,
                      May 29. 1992.
                        16EPA. 1997a. Exposure Factors Handbook,
                      Volumes I. n, and III. Office of Research and
                      Development, Washington. D.C.. EPA/600/P-95/
                      002Fa. b, c. August 1997, www.epa.gov/ordntrnt/
                      ord/webpubs/exposure/index.html.
  "Very simply, an RfC is EPA's acceptable
 concentration in air for a contaminant that causes
 non-cancer health effects. An RfC is an estimate
 (with uncertainty spanning perhaps an order of
 magnitude) of a continuous inhalation exposure to
 the human population (including sensitive
 subgroups) that is likely to be without an
 appreciable risk of deleterious noncancer effects
 during a lifetime.
  18 A cancer slope factor is the slope of the dose-
 response curve in the low-dose region. When low-
 dose linearity cannot be assumed, the slope factor
 is the slope of the straight line from 0 dose (and
 0 excess risk) to the dose at 1% excess risk. An
 upper bound on this slope is usually used instead
 of the slope itself. The units of the slope factor
 usually are expressed as l/(mg/kg-day).
  19 An RfD is an estimate (with uncertainty
 spanning perhaps an order of magnitude) of a daily
 exposure to the human population (including
 sensitive subgroups) that is likely to be without an
 appreciable risk of deleterious effects during a
 lifetime.
  20 EPA. 1998. Integrated Risk Information System.
Online database. (IRIS) Office of Research and
Development (ORD). Cincinnati, OH.

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                Federal Register/Vol.  64,  No. 16i/Wednesday, August 25,  1999/Proposed Rules
                                                                       46489
 EPA 1997b)2'; (3) EPA's National Center
 for Environmental Assessment (NCEA)
 provisional values, and (3) benchmarks
 developed by the California
 Environmental Protection Agency
 (CALEPA)22. The specific health
 benchmarks used in the analysis are
 presented in Appendix C of the
 Background Document for the
 Chlorinated Aliphatics Risk
 Assessment.

 f. What Are the Risks From Exposure to
 Chlorinated Aliphatics Wastewaters,
 and EDC/VCM and Methyl Chloride
 Sludges?
  The following sections discuss EPA's
 estimates of individual and population
 risk for chlorinated aliphatics
 wastewaters, EDC/VCM sludges, and
 methyl chloride sludges.

 i. What Are the Individual Risks?
  EPA combined estimates of dose and
 estimates of toxicity  (the health
 benchmarks) to calculate individual
 incremental lifetime carcinogenic risk
 estimates and hazard quotients for the
  21 EPA. 1997b. Health Effects Assessment
Summary Tables: Annual Update. (HEAST) Office
of Emergency and Remedial Response. Washington,
D.CJuly.
  22 California Environmental Protection Agency
(CalEPA). 1997. Air Toxics Hot Spots Program Risk
Assessment Guidelines: Technical Support
Document for Determining Cancer Potency Factors.
Draft for Public Comment. Office of Environmental
Health Hazard Assessment, Berkeley, CA,
www.oehha.org/ra	guidance/.
 potential contaminants of concern in
 chlorinated aliphatic wastewaters, EDC/
 VCM sludge, and methyl chloride
 sludge. Complete results of these
 calculations are provided in the Risk
 Assessment Technical Background
 Document for the Chlorinated
 Aliphatics Listing Determination. EPA
 typically considers a decision to list a
 waste when carcinogenic risks are
 1x10~5 or greater or when the
 noncancer HQ is 1 or greater. None of
 the contaminants generated noncancer
 hazards with an HQ greater than 1, nor
 did the sum of the contaminant HQs
 exceed 1. In summing carcinogenic risk
 estimates and noncancer hazard
 quotients, EPA does not sum those risks
 or hazards that could not occur within
 the lifetime of an individual. For
 example, if estimated risks  due to
 nongroundwater pathways  occur during
 the operating or  post-closure life of the
 unit (that is, due to releases to air and
 runoff/erosion) and risk via the
 groundwater pathways are not projected
 to occur for hundreds, or even
 thousands, of years due to long times
 required for contaminant migration,
 then these two pathway risks would not
 be added together.
  The following  sections present
separately our deterministic and
probabilistic estimates of individual risk
for:
  • Wastewaters from the production of
chlorinated aliphatic chemicals,
   • Wastewater treatment sludges from
 the production of EDC/VCM, and
   • Wastewater treatment sludges from
• the production of methyl chloride.

 Chlorinated Aliphatic Wastewaters

   Table III-l summarizes the significant
 (greater than lxlO~5 risk estimates for
 chlorinated aliphatic wastewaters
 managed in onsite aerated biological
 wastewater treatment tanks.. The highest
 deterministic risk estimate, 2xlO~5,
 occurs for the farmer. The risk is
 attributable to the farmer's ingestion of
 dioxins, which in Table III-l are
 expressed as the 2,3,7,8-
 tetrachlorodibenzo-p-dioxin (TCDD)
 toxicity "equivalent (TEQ). The farmer's
 high end deterministic risk falls slightly
 below the 90th percentile probabilistic
risk estimate (the 80th percentile risk
estimate is IxlO"5). Table IH-2
summarizes our deterministic estimates
of risk due to the direct inhalation of
chloroform. The high end chloroform
risks are 3xlO~6 for the farmer and
2xlO~6 for all other receptors. The
chloroform deterministic risk estimates
for the adult receptors are roughly equal
to the 97.5th percentile probabilistic
risk estimates. Although the chloroform
risks are not greater than lxlO~5, they
are additive to the risks that EPA
estimated for dioxins because they
would occur within the same timeframe.
BILLING CODE 6560-50-P

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46490
Federal Register/Vol. 64, No.  164/Wednesday, August 25, 1999/Proposed Rules
     Table III-l. Summary of Excess Lifetime Dioxin Cancer Risk (expressed as 2,3,7,8-TCDD
            TEQ) Attributable to Management of Chlorinated Aliphatic Wastewaters
                            in an Aerated Biological Treatment Tank
                            Table III-l A. Deterministic Risk Results
Receptor
Farmer
Child of Fanner
Home Gardener
Adult Resident/Fisher
Child of Resident
HE
2E-05
7E-06
2E-08
2E-09
7E-09
CT
4E-07
3E-07
1E-09
1E-11
4E-11
High End Parameters
Exposure Duration and Contaminant Concentration
Contaminant Concentration and Waste Quantity
Exposure Duration and Contaminant Concentration
Contaminant Concentration and
Meteorological Location
                                HE = High End; CT = Central Tendency

                            Table Ill-IB. Probabilistic Risk Results
Receptor
Farmer
Child of Farmer
Age 1-5
Age 6-11
Age 12-18
Percentile
50th
2E-07
90th
5E-05
95th
1E-04
97.5th
3E-04
100th
2E-02

2E-07
2E-07
2E-07
4E-05
4E-05
4E-05
1E-04
1E-04
1E-04
2E-04
2E-04
2E-04
8E-03
9E-03
1E-02

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Federal Register/Vol. 64. No.  164/Wednesday, August 25, 1999/Proposed Rules
46491
    Table III-2. Summary of Excess Lifetime Chloroform Cancer Risk
    Attributable to Management of Chlorinated Aliphatic Wastewaters
                in an Aerated Biological Treatment Tank
                  Table III-2-A: Deterministic Results
Receptor
Farmer
Child of Farmer / Child Resident
Home Gardener/Fisher/Adult Resident
HE
3E-06
2E-06
2E-06
CT
8E-08
8E-08
8E-08
High End Parameters
Exposure Duration and
Distance To Receptor
Contaminant concentration and
Distance to Receptor
                   Table III-2B. Probabilistic Results
' < * "•
Receptor I " '
Farmer
Adult Resident/Home Gardener/Fisher
Child Resident
Age 1-5
Age 6-11
Age 12-18
Child of Farmer
Age 1-5
Age 6-11 . |
Age 12-18 |
! ,
t
50th
3E-08
2E-08
•

3E-08
3E-08 i
;
2E-08

6E-08 I
4E-08 j
3E-08 i
-
90th
6E-07
5E-07

6E-07
6E-07
4E-07

1E-06 !
i
8E-07 !
6E-07
Percent!!*
95th
1E-06
1E-06

1E-06
1E-06
8E-07

2E-06
2E-06
1E-06
i
97.5th
2E-06
2E-06

2E-06
2E-06
1E-06

4E-06
3E-06
2E-06
s
f 100th
| 6E-05
I 5E-05

6E-05
5E-05
4E-05

6E-05
5E-05
4E-05

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46492
Federal  Register/Vol. 64, No.  164/Wednesday,  August 25,  1999/Proposed Rules
EDC/VCMSludges

  Tables III-3 and III-4 summarize the
significant (greater than lxlO-s) risk
estimates for EDC/VCM wastewater
treatment sludges managed in an onsite
land treatment unit. In all cases, we
estimated that the highest risk occurs for
the fanner. Table III-3 presents dioxin
(expressed as 2,3,7,8-TCDD TEQ) risk
estimates for the land treatment unit
nongroundwater pathways. The high
end deterministic risk estimate for the
farmer is 2xlO~4, which also
corresponds to the 95th percentile
                        probabilistic risk estimate. Table III-4
                        presents arsenic risk estimates for the
                        land treatment unit groundwater
                        pathways. The high end deterministic
                        risk estimate for the farmer is lxlO~5,
                        which falls between the 97.5th percentile
                        probabilistic risk estimate (6xlO~6) and
                        the 100th percentile probabilistic risk
                        estimate (5x10"5). EPA estimates that
                        the groundwater pathway risks in Table
                        III-4 would occur approximately 1500
                       years in the future, whereas the dioxin
                       nongroundwater pathway risks in Table
                       III-3 would occur during the assumed
                       operating life of land treatment unit.
Table III-5 summarizes the significant
risk estimates for EDC/VCM sludges
managed in an offsite municipal
landfill. The risk estimates presented in
Table HI-5 are arsenic groundwater
pathway risks. The high end
deterministic-risk estimate for the
farmer is 3xlO~5, which falls between
the 97.5th percentile (IxlQ-s) and 100th
percentile (3x10 ~4) probabilistic risk
estimates.  We estimate that the arsenic
risks attributable to the landfill
(presented in Table III-5) would occur
thousands of years in the future.

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   Federal Register/Vol. 64, No. 164/Wednesday, August 25,  1999/Proposed Rules
46493
Table IH-3.  Summary of Excess Lifetime Dioxin (expressed as 23,7,8-TCDD TEQ)
         Cancer Risk Attributable to Management of EDC/VCM Sludge
                     in An Onsite Land Treatment Unit
                   Table III-3A. Deterministic Risk Results
Receptor
Farmer
Child of Farmer
Home Gardener
Fisher
Adult Resident
Child of Resident
HE
2E-04
8E-OS
2E-06
2E-05
2E-06
5E-06
CT
4E-06
3E-06
6E-08
6E-07
5E-08
1E-07
High End Parameters
Exposure Duration and Contaminant Concentration
Contaminant Concentration and Beef Intake
Exposure Duration and Contaminant Concentration
Contaminant Concentration and Soil Intake
                      HE = High End; CT = Central Tendency

                  Table IH-3B. Probabilistic Risk Results
Receptor
Fanner
Home Gardener
Resident
Fisher
Child of Resident
Age 1-5
Age 6-11
Age 12-18
Child of Farmer
Age 1-5
Age 6-11
Age 12-18
Percentile
50tb
7E-06
5E-08
3E-08
2E-07
90th
1E-04
2E-06
1E-06
3E-06
95th
2E-04
2E-06
2E-06
8E-06
97.5th
4E-04
4E-06
2E-06
2E-05
100th
2E-03
2E-05
7E-06
4E-04

1E-07
5E-08
3E-08
2E-06
1E-06
8E-07
4E-06
2E-06
1E-06
6E-06
2E-06
1E-06
1E-04
6E-06
4E-06

9E-06
7E-06
5E-06
1E-04
9E-05
7E-05
2E-04
2E-04
1E-04
3E-04
2E-04
2E-04
1E-03
1E-03
1E-03

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46494      Federal Register/Vol. 64, No. 164/Wednesday. August 25, 1999/Proposed Rules

           Table ITE-4. Summary of Excess Lifetime Arsenic Cancer Risk Attributable to
                               Management of EDC/VCM Sludge
                               in An Onsite Land Treatment Unit
                             Table 1H-4A. Deterministic Risk Results
Receptor
Fanner
Child of Fanner/Child of Resident
Adult Resident/Gardener/Fisher
HE
IE-OS
3E-06
6E-06
CT
8E-07
6E-07
7E-07
High End Parameters
Leachate concentration and Exposure
Duration
                                 HE = High End; CT = Central Tendency
                    Time for Peak concentration to reach receptor is approximately 1500 years
                            Table III-4B. Probabilistic Risk Results
Receptor
Farmer
Adult Resident/Gardener/Fisher
Child Resident
Age 1-5
Age 6-11
Age 12-18
Farm Child
Age 1-5
Age 6-11
Age 12-18
Percentile
50th
9E-08
7E-08
90th
2E-06
1E-06
95th
4E-06
3E-06
97.5th
6E-06
5E-06
100th
5E-05
3E-05

6E-08
5E-08
4E-08
1E-06
1E-06
9E-07
2E-06
2E-06
2E-06
4E-06
3E-06
3E-06
5E-05
4E-05
4E-05

1E-07
8E-08
6E-08
2E-06
2E-06
1E-06
4E-06
3E-06
2E-06
6E-06
4E-06
4E-06
4E-05
2E-05
2E-05

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              Federal  Regisfer/VoI.  64, No. 164/Wednesday.  August 25, 1999/Proposed Rules
46495
              Table III-4. Summary of Excess Lifetime Arsenic Cancer Risk Attributable to
                                  Management of EDC/VCM Sludge
                                  in An Onsite Land Treatment Unit
                                Table III-4A. Deterministic Risk Results
Receptor
Farmer
Child of Farmer/Child of Resident
Adult Resident/Gardener/Fisher
HE
1E-05
3E-06
6E-06
CT
8E-07
6E-07
7E-07
High End Parameters
Leachate concentration and Exposure
Duration
                                   HE = High End; CT = Central Tendency

                       Time^for Peak concentration to reach receptor is approximately ] 500 years
                               Table III-4B. Probabilistic Risk Results
Receptor
Farmer
Adult Resident/Gardener/Fisher
Child Resident
Age 1-5
Age6-ll
Age 12-18
Farm Child
Age 1-5
Age 6-1 1
Age 12-18
Percentile
50th
9E-08
7E-08
90th
2E-06
1E-06
95th
4E-06
3E-06
97.5th
6E-06
5E-06
100th
5E-05
3E-05

6E-08
5E-08
4E-08
1E-06
1E-06
9E-07
2E-06
2E-06
2E-06
4E-06
3E-06
3E-06
5E-05
4E-05
4E-05

1E-07
8E-08
6E-08
2E-06
2E-06
1E-06
4E-06
3E-06
2E-06
6E-06
4E-06
4E-06
4E-05
2E-05
2E-05
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  46496
Federal Register/Vol. 64, No. 164/Wednesday,  August 25,  1999/Proposed Rules
 Methyl Chloride Sludges
   EPA conducted a deterministic
 analysis to estimate nongroundwater
 (air) pathway risks associated with
 management of methyl chloride sludges
 in an onsite landfill. All
 nongroundwater pathway carcinogenic
 risks were less than 1 x lO"8, and all
 noncancer HQs were less than 0.0001.
   For groundwater pathways, EPA
 performed a screening analysis that
 maximizes estimates of risk or hazard to
 human receptors. EPA calculated the
 carcinogenic risk for an adult who
 ingests (drinks) 1.4 liters of leachate
 from the landfill for 350 days per year
 for 58 years. EPA also calculated the
 noncancer hazard for a child who
 ingests 1.4 liters of leachate from the
 landfill for 350 days per year for 9  years.
 None of the noncancer HQs was greater
 than 1, Arsenic was the only carcinogen
 with risk in excess of 1 x 10~s.
 Specifically, an adult's risk due to
 ingesting leachate from methyl chloride
 sludges for 58 years was 5x10~5 due to
 arsenic. EPA discusses our evaluation of
 this risk in Section III.EAb.
 ii. What are the Population Risks?
   EPA expects that the population  risks
 resulting from management of
 chlorinated aliphatics wastewaters in
 tanks and EDC/VCM sludges in onsite
 land treatment units and landfills are
 not significant. With regard to
 groundwater pathway risks. EPA
 believes that the number of domestic
 drinking water wells (thus the
 population) potentially affected by
 groundwater contaminated with arsenic
 originating from the landfill and the
 land treatment unit would be very
 small. Furthermore, we estimate that the
 arsenic concentrations predicted in
 receptor (drinking water) wells will
 result in risks only slightly above
 1X 10~5 for that very small number of
 people.
   For nongroundwater pathways, EPA
 performed a screening evaluation of
 population risk for the waste
 management scenario and pathway that
 resulted in the greatest individual risk
 estimate of any pathway evaluated in
 the chlorinated aliphatics risk
 assessment. Specifically, EPA evaluated
 risk associated with ingestion of beef
 and dairy products contaminated with
 dioxins derived from the onsite EDC/
 VCM land treatment unit. As presented
 previously, under the land treatment
 unit scenario the farmer's total
 individual excess lifetime cancer risk
 from ingestion of beef and dairy was
 2 x 10 - * for high end exposures and
3x 10~6 for central tendency exposures.
Although the individual risk estimates
                        for the farmer exposed to dioxins from
                        EDC/VCM sludge managed in a land
                        treatment unit are an order of magnitude
                        greater than those for the farmer
                        exposed to dioxins from chlorinated
                        aliphatics wastewaters managed in
                        tanks, is possible that population risks
                        resulting from releases from chlorinated
                        aliphatics wastewaters would exceed
                        those resulting from releases from EDC/
                        VCM sludges. This might occur because
                        there is only one land treatment unit
                        that is used to manage EDC/VCM
                        sludge, and we expect that there may be
                        many aerated biological wastewater
                        treatment tanks used to manage
                        chlorinated aliphatics wastewaters.
                        Nevertheless, EPA believes that it is
                        reasonable to assume that the
                        population risks for the land  treatment
                        unit likely would be greater than those
                        for the wastewater tanks because there
                        would need to be at least 10 wastewater
                        treatment tanks with surrounding cattle
                        populations similar to that of the land
                        treatment unit to produce a population
                        risk estimate equivalent to that of the
                        land treatment unit.
                         Results of the population risk analysis
                       for the land treatment unit indicate that
                       2 x10~4 excess cancer cases would be
                       expected annually in a population of
                        1,410 individuals ingesting beef
                       produced from cattle raised within 2
                       kilometers of the land treatment unit
                       over a 40-year operational life for the
                       land treatment unit (dairy cattle are not
                       raised in the county where the land
                       treatment unit is located, thus we did
                       not evaluate ingestion of dairy products
                       in the population risk analysis). The
                       average individual risk to the
                       population consuming beef from within
                       the 2-kilometer radius is 2x 10 ~7. We
                       calculated the population potentially
                       affected by a release from the  land
                       treatment unit (1,410 individuals) from
                       the total estimated quantity of
                       contaminated beef and average beef
                       ingestion rates (that is, we calculated
                       how many people would be required to
                       consume all of the contaminated beef
                       assuming typical rates of beef ingestion).
                       It is possible that the contaminated beef
                       would be distributed more widely
                       throughout the population, such that the
                       total number of people ingesting the
                       contaminated beef would be greater
                       than 1,410. However, the population
                       risk estimate would not change because
                       population risk is a function of the
                       number of people who are exposed  (that
                       is, consume contaminated beef) and
                       each person's individual risk (which is
                       a function of the amount of
                       contaminated beef a person consumes).
                       Consequently, as the number of people
                      who are exposed increases, the
  individual risk must decrease
  proportionally because there is only a
  finite amount of contaminated beef, and
  the overall population risk remains the
  same. The Risk Assessment Technical
  Background Document for the
  Chlorinated Aliphatics Listing
  Determination provides a description of
  the procedure used to estimate
  population risks.
   EPA did not estimate population risks
  for the other receptors for whom we
  calculated individual risk estimates
  (residents, children, gardeners, and
  fishers). Because the high end risk for
  the land treatment unit scenario was
  driven by the ingestion of beef and dairy
  products, the population risks for non-
  farmer receptors are expected to be
  considerably lower than 2x  1Q~4.
   Although the population risks
  attributable to the management of
  chlorinated aliphatics wastes are
  expected to be very small, EPA does not
  believe it is appropriate to allow
  contamination from waste management
 activities to cause substantial risk to
 nearby residents simply because there
 are few individuals in the immediate
 vicinity of the waste management units.
 40 CFR 261.11 clearly states that wastes
 are to be listed if they are "capable of
 posing a substantial present  or potential
 hazard." It does not state that a large
 number of people  must be affected.
 However, population  risk may be a
 factor that the Agency could consider
 under 40 CFR 261.11 (a) (3) (xi) ("other
 factors as may be appropriate").
   EPA's Guidance for Risk
 Characterization (EPA 1995) states that
 when small populations are exposed,
 population risk estimates may be very
 small, however, "in such situations,
 individual risk estimates will usually be
 a more meaningful parameter for
 decision-makers."  Consequently, EPA's
 decision to list wastes has been based
 primarily on the concern over risks to
 those individual's  who are significantly
 exposed, even if there are relatively few
 such individuals. EPA, however,
 requests comment  on whether it would
 be appropriate to give weight to
 population risk in deciding whether to
 list these chlorinated aliphatic wastes as
 hazardous. EPA further invites comment
 on the effect of this approach on the
 Agency's goals with respect to
 environmental justice  in rural areas.

 g. What Is the Toxicity of COCs
 Identified by EPA?
  The two contaminants for which EPA
 calculated significant risks are dioxins
 (expressed as the 2,3,7,8-TCDD TEQ)
and arsenic. The following sections
discuss the ways that these
contaminants affect human health.

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                 Federal Register /Vol. 64. No.  164 /Wednesday, August  25,  1999/Proposed Rules
                                                                        46497
  i. Arsenic
    Arsenic is a naturally occurring
  element in the earth's crust that usually
  exists as an inorganic or organic
  compound, rather than in a free state.
  Arsenic that exists in compounds with
  elements such as oxygen, chlorine, and
  sulfur is referred to as inorganic arsenic;
  arsenic combined with carbon is
  referred to as organic arsenic. Organic
  forms of arsenic are less toxic than
  inorganic forms.
    There is clear evidence that chronic
  exposure to inorganic arsenic in humans
  increases the risk of cancer, and EPA
  classifies inorganic arsenic as a Group
  A—Known Human Carcinogen. Studies
  report that inhalation of arsenic results
  in an increased risk of lung cancer. In
  addition, ingestion of arsenic has been
  associated with an increased risk of
  nonmelanoma skin cancer and bladder,
  liver, kidney, and lung cancer. No
  information is available on the risk of
  cancer in humans from dermal exposure
  to arsenic (EPA 1998).
  ii. Dioxins
   2,3,7,8-Tetrachlorodibenzo-p-dioxin
  (2,3,7,8-TCDD) belongs to the class of
  compounds, chlorinated dibenzo-p-
  dioxins and chlorinated dibenzofurans,
  that are referred to as dioxins. EPA
  issued a draft Health Assessment
  Document for 2,3,7,8-TCDD and Related
  Compounds in 1994. This document is
 a three-volume series consisting of a
 complete reassessment of the toxic
 effects of 2,3,7,8-TCDD (EPA 1994a,
 b 23). The document was reviewed by
 EPA's Science Advisory Board (SAB)
 but has not yet been issued in final
 form.
   EPA has classified 2,3,7,8-TCDD as a
 Group B2—Probable Human Carcinogen
 (EPA 1997b). An increase in lung cancer
 risks was observed among Japanese
 males exposed to 2,3,7,8-TCDD as a
 result of an oil poisoning accident.
 Human studies have also found an
 association between 2,3,7,8-TCDD and
 soft-tissue sarcomas, lymphomas, and
 stomach carcinomas, although for
 malignant lymphomas,  the increase in
 risk is not consistent. The increase in
 risk is of borderline significance for
 highly exposed groups and is less
 among groups exposed to lower levels of
 2,3,7,8-TCDD (EPA 1994b). In animal
  23EPA. 1994a. Health Assessment Document for
2.3,7,8-Tetrachlorodibenzo-p-Dtaxin (TCDD) and
Related Compounds. Volume K praft). Office of
Research and Development, Washington, D.C.,
www.epa.gov/ord/health.
  EPA. 1994b. Health Assessment Document for
2,3,7.8-Tetrachlorodibenzo-p-Dloxin (TCDD) and
Related Compounds. Volume III. (Draft).  Office of
Research and Development, Washington, D.C..
www.epa.gov/ord/health.
  tests, TCDD is one of the most potent
  carcinogens ever evaluated.
    Although EPA has not developed an
  RfD or an RfC for 2,3,7,8-TCDD,
  noncarcinogenic health effects have
  been reported for 2,3,7,8-TCDD. The
  major noncarcinogenic effect from
  exposure to 2,3,7,8-TCDD is chloracne,
  a severe acne-like condition that
  develops within months of first
  exposure to high levels of 2,3,7,8-TCDD.
  For many individuals, the condition
  disappears  after discontinuation of
  exposure, for others it may remain for
  years. There are limited human data to
  suggest the  doses at which chloracne is
  likely to occur (EPA 1994a, b).
  Epidemiological studies report
  conflicting evidence on the
  immunotoxicity of 2,3,7,8-TCDD in,
  humans. Some studies suggest evidence
  of immunotoxicity, such as alterations
  in lymphocyte populations, cell surface
  markers, or  lymphocyte proliferative
  response (ATSDR 1997c24). However,
  studies have not reported changes in the
  immune system directly related to
  2,3,7,8-TCDD exposure (EPA 1994a, b).
  An association has been  reported
  between levels of male reproductive
  hormones and 2,3,7,8-TCDD exposure.
  Decreased testosterone levels were
  detected in several human studies, and
  animal data  are available to support
  these findings. Other effects noted in
  human studies include an association
  between 2,3,7,8-TCDD exposure and the
  following:
   • An  increased risk of diabetes and an
 elevated prevalence of abnormal fasting
 serum glucose levels
   • The induction of cytochrome P-450
  1A1, an enzyme involved in
 biotransformation reactions
   • Elevation of gamma glutamyl
 transferase, a liver enzyme
   • A possible increased risk of
 endbmetriosis, a disease of the female
 reproductive system (EPA 1994a, b).
   Animal studies report reproductive
 and developmental effects from
 exposure to 2,3,7,8-TCDD. These studies
 suggest that altered development may be
 among the most sensitive endpoints of
 2,3,7,8-TCDD exposure. Developmental
 toxicity has been reported to occur in
 several animal species at lower levels
 than male and female reproductive
 toxicity effects. 2,3,7,8-TCDD appears to
 affect a large  number of critical
 developmental effects at specific
 developmental stages. These changes
 can lead  to increases in fetal mortality,
 disruption of organ system structure,
  and irreversible impairment of organ
  function. Developmental toxicity from
  2,3,7,8-TCDD has been seen in fish,
  birds, and mammals (EPA 1994a, b).
    EPA assigned 17 dioxin and furan
  congeners individual toxicity
  equivalency factors (TEFs). TEFs are
  estimates of the toxicity of dioxin-like
  compounds relative to the toxicity of
  TCDD, which is assigned a TEF of 1.0.
  We used the TEFs identified as the I-
  TEFs (International-TEFs) to conduct
  the chlorinated aliphatics risk
  assessment because, until very recently,
  this is the TEF scheme EPA scientists
  have recommended and used for the last
  10 years (EPA 1989) 25 as.
  Documentation supporting the use of
  the  TEEs has been placed in the
  rulemaking record.
    The I-TEFs are presented in Table III-
  6. The I-TEFs are based on a limited
  data base of in w'voand in vitro toxicity
  testing (EPA 1989). The World Health
  Organization (WHO) recently reviewed
  the I-TEFs (Van den Berg et al.  1998)27,
  and determined that three of the I-TEFs
  those for 1,2,3,7,8-PeCDD
  (pentachlorodibenzo-p-dioxin), OCDD
  (octachlorodibenzo-p-dioxin), and
  OCDF (octachlorodibenzofuran),
  required modification  (Table III-6).  EPA
  is in the process of adopting these
  modifications, and consequently
  reviewed the impact that the revised
  (WHO-) TEFs would have on the results
  of the chlorinated aliphatics risk
  assessment. 1,2,3,7,8-PeCDD was not
  detected in dedicated chlorinated
  aliphatic wastewaters,  dedicated EDC/
 VCM sludges, or methyl chloride
 sludges. Consequently, the difference in
 the I-TEF and the WHO-TEF for
  1,2,3,7,8-PeCDD has no impact on the
 results of the risk analyses presented in
 this section. Because of the TEF
 differences for OCDD and OCDF,
 however, the decision to use either the
 I-TEFs or the WHO-TEFs potentially
 may result in large differences in the
 calculated TCDD TEQ concentrations
 for a  given chlorinated aliphatics waste
 sample. Nevertheless, because OCDD
 and OCDF contribute very little to the
 actual risk attributable to dioxin
 compounds, the decision to use either
  24 ATSDR (Agency for Toxic Substances and
Disease Registry). 1997c. Toxicological Profile for
2.3.7,8-Tetrachlorodibenzo-p-dioxin. U.S. Public
Health Service, U.S. Department of Health and
Human Services, Atlanta. GA.
  25 EPA. 1989. Interim Procedures for Estimating
Risks Associated with Exposure to Mixtures of
Chlorinated Dibenzo-p-Dioxins and Furans (CDDs
and CDFs) and 1989 Update. EPA/625/3-89/016.
Risk Assessment Forum. March.
  26 Proposed Rule, "Addition of Dioxin and
Dioxin-Like Compounds; Modification of
Polychlorinated Biphenyls (PCBs) Listing; Toxic
Chemical Release Reporting; Community Right-to-
Know," 62 FR 24887, (May 7. 1997).
  27 Van den Berg, et al. 1998. Toxic Equivalency
Factors (TEFs) for PCBs, PCDDs, PCDFs for Humans
and Wildlife. Environmental Health Perspectives
v.106. n.12. pp. 775-792. December.

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  46498
Federal Register/Vol.  64, No.  164/Wednesday, August 25,  1999/Proposed  Rules
  the 1-TEFs or the WHO-TEFs has
  negligible impact to the overall risk
  results. The Risk Assessment Technical
  Background Document for the
  Chlorinated Aliphatics Listing
  Determination provides separate risk
  results for each of the dioxin congeners
  detected in the wastewaters and sludges
  evaluated.

  TABLE  III-6.  TOXICITY  EQUIVALENCY
    FACTORS (TEFs) FOR DIOXIN  COM-
    POUNDS
Compound
2,3,7,8-TCDD 	
1,2,3,4,5,7,8,9-OCDD ....
1,2,3,7,8,9-HxCDD 	
1,2,3,4,6.7,8-HpCDD 	
1,2,3,4,6,7,8.9-OCDF ....
1,2,3,4,7,8-HxCDD, 	
1,2,3,7,8-PeCDD 	
2,3,7,8-TCOF 	 	
1,2,3.4,7,8,9-HpCDF 	
2,3,4,7,8-PeCDF 	
1,2,3,7,8-PeCDF 	
1,2,3,6,7,8-HxCDF 	
1,2,3.6.7,8-HxCOD 	
2,3,4,6.7,8-HxCDF 	
1,2,3,4.6,7.8-HpCDF 	
1,2,3,4,7,8-HxCDF 	
1,2,3,7,8,9-HxCDF 	

I-TEF
1
0.001
0.1
0.01
0.001
0.1
05
0.1
0.01
0.5
0.05
0.1
0.1
0.1
0.01
0.1
0.1

WHO-
TEF
same
0.0001
same
same
0.0001
same
1
same
same
same
same
same
same
same
same
same
same

 h. What Is the Uncertainty in the
 Human Health Risk Results?
   EPA typically classifies the major
 areas of uncertainty in risk assessments
 as parameter uncertainty, scenario
 uncertainty, and model uncertainty.
 This section identifies the primary
 sources of each of these types of
 uncertainty in the chlorinated aliphatics
 risk assessment, and qualitatively
 describes how each may influence the
 results of the risk assessment.
   Many of the parameters that we used
 to quantify contaminant fate and
 transport and contaminant exposure and
 dose either were not measured or could
 not be measured precisely and/or
 accurately. Some of the most important
 and sensitive parameters in our analyses
 include those that describe waste
 composition; waste management
 practices; site characteristics (for
 example, hydrogeological,
 topographical, meteorological, and soils
 data); the physiologic and behavioral
 exposure characteristics of the
 receptors; the physical, chemical, and
 biochemical properties of the
 contaminants; and toxicological effects.
 We believe that the primary sources of
 parameter uncertainty include the
 following:
  • The risk analyses were based on a
limited set of waste sample data. It is
possible that these data do not represent the
                         true distribution of contaminant
                         concentrations in the waste categories
                         evaluated, resulting in either an
                         overestimation or underestimation of the
                         actual risk to receptors.
                           • EPA obtained little site-specific
                         information regarding waste management
                         units for the chlorinated aliphatics industry,
                         necessitating that we make a number of
                         assumptions regarding waste management in
                         off-site landfills, the land treatment unit, and
                         wastewater tanks. Many of the facilities
                         reported using offsite nonhazardous landfills
                         to dispose of EDC/VCM sludges. We assumed
                         that these landfills are municipal landfills,
                         and modeled typical municipal landfills
                         based on available data. Our major
                         assumptions about the municipal landfills
                         that have the effect of decreasing our risk
                         estimates are that the landfills have daily
                         covers and run-on/run-off controls. Our
                         major assumptions about the municipal
                         landfills that have the effect of increasing our
                         risk estimates are that the landfills are not
                         lined and have no leachate collection
                         systems. For the land treatment unit,  we
                         assumed that no run-on/run-off controls were
                         present to mitigate risk. We assumed  that the
                         industry's wastewater treatment tanks are
                         uncovered (which increases our risk
                         estimates), are aerated (which increases our
                         risk estimates), employ biological treatment
                         techniques (which decreases our risk
                         estimates), have structural integrity (which
                         decreases our risk estimates), and have spill
                         and overflow controls (which decreases our
                         risk estimates).
                          • We typically used regional databases to
                         obtain the parameter values necessary to
                         model contaminant fate and transport.
                         Because the data that we used are not
                         specific to the facilities at which the actual
                         wastes are managed,  the data represent our
                         best estimates of actual site conditions. Use
                         of these databases in  lieu of site-specific data
                        may result in either overestimates or
                        underestimates of risk.
                          •  Sources of uncertainty in toxicological
                        benchmarks include one or more of the
                        following: extrapolation from laboratory
                        animal data to humans, variability of
                        response within the human population,
                        extrapolation of responses at high
                        experimental doses under controlled
                        conditions  to low doses under highly
                        variable environmental conditions, and
                        adequacy of the database (number of studies
                        available, toxic endpoints evaluated,
                        exposure routes evaluated, sample sizes,
                        length of study, etc.).  Toxicological
                        benchmarks are designed to be conservative
                        (that is, overestimate risk) because of the
                        uncertainties and challenges associated with
                        condensing toxicity data into a single
                        quantitative expression. Therefore, use of the
                        current toxicological benchmarks most likely
                        overestimated risk for the pathways
                        evaluated.
                         • EPA estimated the risk of developing
                        cancer from the estimated lifetime average
                        daily dose and the slope of the dose-response
                        curve. A cancer slope  factor is derived from
                        either human or animal data and is taken as
                        the upper bound on the slope of the dose-
                        response curve in the low-dose region,
                        generally assumed to be linear, expressed as
  a lifetime excess cancer risk per unit
  exposure. However, individuals exposed to
  carcinogens in the first few years of life may
  be at increased risk of developing cancer. For
  this reason, EPA recognizes that significant
  uncertainties and unknowns exist regarding
  the estimation of lifetime, cancer risks in
  children. We also note that the analysis of
  cancer risks in children has not been
  externally peer reviewed.
  We expect that the various sources of
  parameter uncertainty in our risk
  assessment counterbalance'each other,
  such that parameter uncertainty will not
  result in a significant overall increase or
  decrease in risk.
   Scenario uncertainty results from the
  assumptions we make regarding how
  receptors become exposed to
  contaminants. This uncertainty occurs
  because of the difficulty and general
  impracticality of making actual
  measurements of a receptor's exposure.
  Exposure modeling relies heavily on
  default assumptions regarding
  population activity patterns, mobility,
  dietary habits, body weights, and other
  factors. Because the risk estimates
  presented in today's notice  are for
  hypothetical chronic exposures and are
  designed to provide a realistic range of
 potential receptor exposure scenarios,
 we develop predictions of long-term
 average exposures for each receptor.
 Although it is possible to study various
 populations to determine their exposure
 parameters (for example, age-specific
 soil ingestion rates or intake rates for
 food) or to assess past exposures
 (epidemiological studies) or current
 exposures, risk assessment is about
 prediction. Therefore, long-term
 exposure monitoring in this context is
 infeasible. The double-high  end
 deterministic approach coupled with
 the probabilistic approach is designed to
 provide reasonable estimates of
 potential long-term exposures for
 various receptors. The Exposure Factors
 Handbook provides the current state-of-
 the-science regarding exposure
 modeling and assumptions and was
 used in the risk assessment.  To the
 extent that actual exposure scenarios
 vary from the assumptions we used,
 risks could be underestimated or
 overestimated. Although there could be
 individuals living near a waste disposal
 site who have higher exposures than
 those presented, it is more likely that
 actual exposures for most of these
 individuals would fall within the
 predicted range, and, moreover, would
 be similar to those predicted for the
 central tendency or 50th percentile.
  Models and their mathematical
expressions are simplifications of reality
that are used to approximate real-world
conditions and processes, and their

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                                                                       46499
  relationships. Models do not include all
  parameters or equations necessary to
  express reality because of the inherent
  complexity of the natural environment,
  and the lack of sufficient data to
  describe the natural environment.
  Consequently, models are based on
  numerous assumptions and
  simplifications, and reflect an
  incomplete understanding of natural
  processes. We selected the models used
  in this risk assessment, described in
  Section III.D.l.d,  based on science,
  policy, and professional judgment. We
  selected the wastewater emissions
  model, the air dispersion and deposition
  models, the indirect exposure equations,
  and the groundwater model because
  they provide the information needed for
  this analysis and because we generally
  consider them to be state-of-the-science.
  Even though the models used in the risk
  analysis are used widely and have been
  accepted for numerous applications,
  they each retain significant sources of
  uncertainty that as a whole could result
  in either an overestimation or
 underestimation of risk.
   One of the sources of uncertainty is
 our assumption that vapor emissions of
 dioxins from chlorinated aliphatics
 wastewaters and wastewater  treatment
 sludges do not appreciably sorb to
 particulate matter in the ambient air in
 approximately 1.2 minutes, the average
 the time required for emissions from the
 waste management units to reach a
 receptor located 300 meters away (our
 central tendency distance to receptor).
 Sorption of dioxins onto particles in air
 would remove dioxins from the vapor
 phase, thereby reducing the vapor-phase
 diffusion of dioxins into plants. As a
 result, our calculated dioxin
 concentrations in plants, and in animals
 consuming plants  (particularly grasses),
 are higher  than they would be if we
 assumed that some fraction of the vapor
 phase dioxin irreversibly partitions onto
 particles in the ambient air. However,
 given the uncertainties regarding rates
 of dioxin partitioning, magnitude of
 partitioning, and other factors
 potentially influencing dioxin sorption
 onto particles (such as temperature,
 humidity, and particle size, type and
 density), we believe our assumption that
 dioxins remain as vapors during their
 transport from the waste management
 unit source to the receptor location is
 appropriate. Because we understand
that our assumption results in increased
risk estimates, we are soliciting public
comment on this issue. We also charged
peer reviewers with providing comment
on the issue during the peer review
process, discussed in Section III.D.3.,
below.
  2. What Are the Potential Risks to
  Ecological Receptors?
    EPA conducted an ecological risk
  screening analysis for the tank scenario
  for chlorinated aliphatics wastewaters,
  the land treatment unit and landfill
  waste management scenarios for EDC/
  VCM sludges, and for the landfill waste
  management scenario for methyl
  chloride sludges. The purpose of this
  analysis was to identify whether there is
  potential for adverse ecological effects
  resulting from the management of
  chlorinated aliphatics wastewaters,
  EDC/VCM sludges, and methyl chloride
  sludges. The screening analysis
  compares the modeled media
  concentrations to protective media
  concentrations in the form of a hazard
  quotient. When the hazard quotient
  exceeds 1, there is potential for adverse
  effects. If the hazard quotient is less
  than 1, we do not expect adverse effects
  for a particular ecological receptor. The
  amount by which the hazard quotient
  exceeds 1 suggests the potential for
  adverse ecological effects; however, the
  screening results do not demonstrate
  actual ecological effects, nor do they
  indicate whether those effects will have
  significant implications for ecosystems
  and their components.
   For the screening analysis, EPA
  applied a methodology designed to
 evaluate the potential for adverse
 ecological effects for selected receptors
 in generalized terrestrial and freshwater
 aquatic systems. The ecological risk
 screening analysis focused on a limited
 set of constituents of concern that were
 modeled for the human health risk
 analysis. For the selected ecological
 receptors, we developed protective
 contaminant concentrations in soil,
 sediment, and surface water that are
 based on conservative assumptions
 regarding exposure pathways and
 dietary preferences. The analysis
 included the following steps: (1) we
 developed chemical stressor
 concentration limits (CSCLs)2S; (2) we
 compared the CSCLs to exposure point
 concentrations and calculated hazard
 quotients; and (3) we  characterized key
 uncertainties and their impact on
 hazard quotients. We  describe the
 results of this process in detail in the
 Risk Assessment Technical Background
 Document for the Chlorinated
 Aliphatics Listing Determination.
  Based on the results of the analysis,
 we do not anticipate significant risk for
 the ecological receptors evaluated under
 either the high end or central tendency
  28 Chemical stressor concentration limits are the
containment concentrations in environmental
media that are presumed to cause de minimis
effects to ecological receptors.
  chlorinated aliphatic wastewater tank,
  EDC/VCM landfill, or methyl chloride
  landfill scenarios. However, there is
  indication of potential significant risk to
  ecological receptors under both the high
  end and central tendency EDC/VCM
  land treatment unit scenarios. These
  results support our conclusions for the
  human health risk analyses for EDC/
  VCM and methyl chloride sludges, that
  is, that there are risks posed by the
  management of EDC/VCM sludges in
  land treatment units, but not by the
  management of EDC/VCM sludges or
  methyl chloride sludges in landfills.
  Although we did not explicitly consider
  risks to threatened or endangered
  species, the CSCLs are protective media
  concentrations based on Agency-wide
  standards (e.g., Ambient Water Quality
  Criteria) and  no observed adverse effects
  levels. The protective nature of the
  CSCLs implies some degree of
  protection for species already
  considered to be under stress. The
  ecological risk screening results are
  described in detail in the Risk
  Assessment Technical Background
  Document for the Chlorinated
  Aliphatics Listing Determination.
  3. Did EPA'Conduct a Peer Review of
 the Risk Assessment?
   The Agency has submitted the risk
 assessment to three independent experts
 for peer review. Their comments have
 been received and are in the docket for
 today's proposed rule. Due to the time
 constraints for proposal of this rule, the
 Agency has not yet reviewed and
 addressed those comments. Both the
 peer review comments and the public
 comments will be addressed in the final
 rulemaking.

 E. Waste-Specific Listing Determination
 Rationales
   This section presents the rationale for
 today's proposed listing determinations
 for each of the identified categories of
 wastewaters and wastewater treatment
 sludges from the chlorinated aliphatic
 industry. EPA considered the listing
 criteria set put in 40  CFR 261.11, as
 incorporated into the risk assessments
 presented in Section III.D. above, as
 well as any other information relevant
 to the criteria, in making each of the
 listing determinations presented in this
 section. The criteria provided in 40 CFR
 261.11 include eleven factors for
 determining "substantial present or
 potential hazard to human health and
 the environment." As previously
 discussed at the beginning of Section
 III.D., nine of these factors relate to the
risk assessments (constituent toxicity,
concentration, waste quantity, migration
potential, persistence, degradation

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Federal  Register/Vol. 64,  No. 164/Wednesday, August 25,  1999/Proposed Rules
       potential, bioaccumulation potential.
       plausible mismanagement, and other
       regulatory actions). Damage incidents
       (261.11 (a) (3) (ix)) are investigated, and
       those that can be attributed to the
       wastes being evaluated are identified
       and considered in our evaluation.
        The following sections presents the
       rationale for each of the proposed listing
       determinations for wastes generated by
       the chlorinated aliphatics industry. Our
       rationale includes the results of our
       consideration of each of the factors
       listed above, the results of our risk
       assessment and other factors as may be
       appropriate.
       1. Chlorinated Aliphatics Wastewaters
       a. Wastewaters From the Production of
       Chlorinated Aliphatics
        As explained previously in Section
I       III.A, 1., the Agency segregated
       wastewaters from the chlorinated
       aliphatics industry into two waste
       groupings. Based upon current waste
       management practices, we grouped all
       chlorinated aliphatic wastewaters,
       except for those wastewaters generated
       from the production of vinyl chloride
       monomer using mercuric chloride
       catalyst in an acetylene-based process,
       into a single waste category for the
       listing determination investigation. We
      decided to study these wastewaters
      collectively because most chlorinated
      aliphatic manufacturers commingle
      wastewaters generated by individual
      processes prior to treating the
      wastewaters in a common wastewater
      treatment system.29 In addition, many
      process wastewaters generated from the
      production of chlorinated aliphatic
      hydrocarbons contain similar
      constituents of concern.
        EPA is  proposing to list as hazardous
      process wastewaters generated from the
      production of chlorinated aliphatic
      hydrocarbons (other than those
      wastewaters generated from the
      production of vinyl chloride monomer
      using mercuric chloride catalyst in an
      acetylene-based process, discussed later
      in Section m.E. 1 .b of this preamble).
      The wastewaters meet the criteria set
      out at 40 CFR 261.11 (a) (3) for listing a
      waste as hazardous and are capable of
      posing a substantial present or potential
      hazard to human health or the
      environment when mismanaged. As
      already described in the risk assessment
      results in  Section III.D. 1 .f. of this
      preamble, we identified risks of concern
      associated with air releases of dioxins
      from wastewater treatment systems. The
      results of our risk analysis, which
       **See Appendix D to Listing Background
     Document for the Chlorinated Aliphatic Listing
     Determination.
                        explicitly considers the factors listed in
                        40 CFR 261.11 (a) (3)(i)-(x). shows
                        potential risks of concern for the farmer
                        and child of farmer receptors, where the
                        contaminants of concern are dioxins.
                        The risk assessment results were
                        presented previously in Table III-l of
                        Section III. D.I.f.

                        i. What Information Led EPA To
                        Propose To List as Hazardous Process
                        Wastewaters From the Production of
                        Chlorinated Aliphatic Hydrocarbons?
                         Responses to the 1996 RCRA Section
                        3007 chlorinated aliphatic industry
                        survey indicated that approximately
                        11.5 million metric tons of chlorinated
                        aliphatic wastewaters are generated
                        annually. Survey responses and other
                        publicly-available information also
                        indicate that virtually all chlorinated
                        aliphatic manufacturers treat these
                        wastewaters in on-site, tank-based
                        wasteWater treatment systems prior to
                        direct discharge of these wastewaters in
                        accordance with facility-specific NPDES
                        permits. Other wastewater management
                        practices identified include discharge
                        off-site to either publicly-or privately-
                        owned treatment works (POTW,
                        PrOTW), and storage and treatment in
                       tanks prior to disposal in on-site
                       underground injection wells. None of
                       the facilities that responded to the
                       questionnaire indicated that chlorinated
                       aliphatic wastewaters currently are
                       managed in surface impoundments.
                         The Agency evaluated air pathway
                        (vapor emissions) risks associated with
                       the management of chlorinated
                       aliphatics in wastewater treatment
                       tanks. Our analysis of air emissions
                       from the treatment of wastewaters was
                       limited to an evaluation of air emissions
                       from tank-based systems because the
                       results of the RCRA Section 3007 survey
                       showed that the chlorinated aliphatics
                       industry manages wastewaters
                       exclusively in tanks. Surface
                       impoundments currently are not being
                       used by this industry for the treatment
                       of wastewaters, and based upon a
                       review of industry trends, we anticipate
                       that this industry will not use surface
                       impoundments in the future. First, all of
                       our data indicate that surface
                       impoundments are no longer used by
                       the chlorinated aliphatics
                       manufacturers. In the 1992 RCRA 3007
                       survey responses, 5 facilities indicated
                       they were using surface impoundments
                       in the treatment of wastewater. In the
                       1997 RCRA 3007 survey update, only
                       two facilities indicated they were using
                       surface impoundments. We contacted
                       the five facilities to confirm whether or
                       not surface impoundments were being
                       used, and learned that all of the
                       impoundments had closed. Second, we
  do not believe it is likely that
  established tank-based wastewater
  treatment systems would be abandoned
  for surface impoundments-based
  systems, given that chlorinated aliphatic
  manufacturers have made the decision  ,
  to convert to tank-based systems outside
  of regulations and after having
  considered other variables (e.g.,  liability
  concerns) and weighing all risks and
  benefits of tank-based systems. Further,
  impoundment-based systems are land
  intensive and land is valuable,
  particularly in industrial areas. Once a
  facility has reclaimed land previously
  used for surface impoundments, the
  facility is likely to then use that  land for
  higher value operations. Therefore, we
  did not-view surface impoundments as
  a plausible management for wastewaters
  within this industry.
   Given that wastewaters are managed
  in aerated biological treatment tanks,
  the emissions pathway of most concern
  is air emissions. Although such tanks
  often are open and may facilitate air
 releases, wastewater treatment tanks do
 restrict or eliminate the possibility of
 releases to groundwater via leaching.
 Tanks used to store and treat
 wastewaters generally are equipped
 with overflow and spill controls  and are
 managed in compliance with structural
 integrity requirements that restrict the
 physical migration of wastes from the
 unit into the surrounding soil. However,
 given that a majority of the tanks used
 to treat chlorinated aliphatic
 wastewaters are designed to allow for
 aeration of the wastewater, these units
 may not completely control releases due
 to vapor emissions. Therefore, EPA
 determined that contaminant transport
 via air releases from tank-based systems
 was the most logical source of potential
 risk from managing these wastewaters.
   EPA collected 41 samples of
 chlorinated aliphatic wastewaters
 generated at 15 facilities. From the
 samples and analytical results we
 selected data for our risk analysis that
 represent wastewaters at the point
 where they are commingled prior to
 treatment. Since it is common for
 wastewaters to be combined prior to
 treatment in on-site wastewater
 treatment facilities, these commingled
 wastewaters are most representative of
 the wastewaters that actually are
 managed in tanks. Further, because  the
 RCRA Section 3007 survey responses
 indicated that some facilities may
 commingle chlorinated aliphatic
 process wastewater with non-
 chlorinated aliphatic (e.g., petroleum
 refinery) process wastewater prior to
treatment, we conducted our risk
assessment using only waste
characterization and volume data

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                 Federal  Register/Vol. 64, No. 164/Wednesday, August 25,  1999 / Proposed Rules
                                                                       46501
  representing "dedicated" wastewaters.
  We used data from these facilities to
  ensure that the results of our risk
  assessment would reflect only risks
  associated with the management of
  chlorinated aliphatic wastewaters.
    We also centered our analysis on an
  evaluation of chlorinated aliphatic
  wastewaters not currently defined as
  hazardous waste, and that are managed
  in aerated, uncovered biological
  treatment tanks. While not every facility
  currently uses biological treatment, this
  was the predominant practice observed
  during facility site visits and indicated
  in the  RCRA Section 3007 survey. The
  risk analysis assumed that biological
  treatment occurs in aerated, uncovered
  tanks,  because these conditions are
  typical for biological treatment in tanks
  and were confirmed to be occurring at
  some chlorinated aliphatic facilities
  treating non-hazardous, dedicated
  chlorinated aliphatic wastewaters. Also,
  because aeration increases air
  emissions, this scenario is expected to
  result in the highest risk estimates
  (compared with non-aerated and/or
  covered tanks). Based upon survey
 response information and follow up
  inquiries with facility personnel,
 biological treatment in uncovered,
 aerated tanks was considered to be a
 plausible management scenario for
 wastewaters in the chlorinated
 aliphatics industry.
   The risks associated with vapor
 emissions of dioxin, as presented
 previously in Table III-l in Section
 III.D. l.f., are significant for two
 receptors, the farmer and the farmer's
 child, and for one exposure route, the
 consumption of beef and dairy products.
 The high-end cancer risk for the farmer
 is 2E-05 and the central tendency risk
 is 4E-07. As explained previously, this
 risk is attributed to a local farmer's
 ingestion of dioxin due to his
 consumption of fruits, vegetables, beef
 and dairy products, all of which are  .
 grown or raised in an agricultural field
 located near a wastewater treatment unit
 used to treat chlorinated aliphatic
 wastewaters, as well as the farmer's
 incidental ingestion of soil from the
 agricultural field (see Section III.D.l.c).
 The high-end cancer risk for the
 farmer's child is 7E-06 and the central
 tendency risk is 3E-07. EPA also ran a
 Monte Carlo risk assessment on the air
 releases from these tanks. Probabilistic
 risk assessment results showed a risk of
 1E-4 at the 95th percentile for the
 farmer, and for the child of farmer. This
 confirms the reasonableness of the
 deterministic analysis and the fact that
regulation would be necessary to reduce
the risk  from the tank emissions to
protect the farmers. At the 50th
  percentile, the probabilistic risk was
  2E-7 for the farmer and the child of
  farmer.
    As described in Section III.D.l.f. of
  this preamble, the high-end parameters
  used in the risk assessment for dioxin
  emissions from wastewater treatment
  tanks were waste concentration and
  exposure duration. These results are
  based upon a concentration of dioxin in
  wastewaters associated with the highest
  concentration of dioxin we found for the
  wastewater samples used in the
  analysis. Further discussion of the
  assumptions and parameters used in the
  risk assessment is provided in Section
  III.D. of this preamble and in the Risk
  Assessment Technical Background
  Document for the Chlorinated
  Aliphatics Listing Determination that is
  in the docket for today's proposed rule.
   Our analyses also snowed marginal
  risks of concern for the farmer, child of
  farmer, home gardener, adult and child
  resident, and fisher, from direct
  inhalation of chloroform. The high-end
  cancer risk for the farmer from direct
  inhalation of chloroform is 3E-06. In
  addition, the high end cancer risk to the
  child of farmer, child resident, adult
  resident, home gardener, and the fisher
 from direct inhalation of chloroform is
  2E-06. The central tendency risk from
 chloroform inhalation for the farmer,
 child of farmer, child resident, home
 gardener, fisher and adult resident is
 8E-08.
   EPA is confident that the constituents
 of most concern, dioxins and
 chloroform, were identified. In addition,
 we are confident that the assumptions
 and parameter values used in our risk
 modeling reflect "high-end" or
 "reasonable worse case" circumstances.
 Risks are  unlikely to be significantly
 higher than shown by our modeling
 results. In Section III.D.l.h. of today's
 preamble, we  describe in more detail
 sources of potential uncertainty in the
 risk results that may result in under- or
 over-estimations of risk.
   Based on an analysis of the risks
 associated with current management
 practices, EPA is proposing to list
 wastewaters from the production of
 chlorinated aliphatic hydrocarbons as
 hazardous waste (EPA Hazardous Waste
 Number K173.) EPA's proposal to list
 this waste is consistent with the
 guidance the Agency has used for
 determining that a waste is hazardous
 (see 59 FR 66077), i.e., the risks
associated with management of
wastewaters in aerated biological
treatment  tanks due to vapor emissions
of dioxins are above the 1E-5 listing
benchmark. This guidance also provides
that EPA can consider additional factors
in cases where risk assessment results
  indicate a risk level of between 1E-4
  and 1E-6, as is the case here. These
  additional factors include: certainty of
  waste characterization; certainty in risk
  assessment methodology; coverage by
  other regulatory programs; waste
  volume; evidence of co-occurrence of
  hazardous constituents; damage cases
  showing actual impact to human health
  or the environment; and presence of
  toxicants of unknown or unquantifiable
  risk.
    With regard to certainty of waste
  characterization, as explained in Section
  III.D., the Agency collected and
  analyzed 41 samples of wastewaters
  generated from the production of
  chlorinated aliphatic chemicals, six of
  which were collected at the influent
  ("headworks") of the wastewater
  treatment system. Given that we used
  these six "dedicated" samples in our
  risk assessment, we are certain that our
  analysis evaluated without question the
  risks attributable to the wastewaters of
  concern.
   With respect to certainty in risk
  assessment methodology, we note that
  there is discussion of uncertainty in the
  risk assessment methodology in section
  III.D. l.h. of today's preamble. As
  mentioned in that section, we selected
  the models we used because we
  generally consider them to be state-of-
  the-science, and because they are used
 widely and have been accepted for
  numerous applications. However, as
 mentioned, they each retain significant
 sources of uncertainty that as a whole
 could result in either an overestimation
 or underestimation of risk. Should the
 Agency determine, based upon public
 comment or as a result of the peer
 review of the risk assessment
 methodology, that the wastewater risk
 assessment has overestimated the risks
 such that a decision to list this residual
 is not warranted, the Agency may
 ultimately decide against listing this
 waste.
   We considered coverage by other
 regulatory programs in making our
 proposed listing determination for
 chlorinated aliphatic wastewaters. In
 fact, as discussed further below, our
 decision to propose to list these
 wastewaters and to propose technical
 standards to address air emissions from
 treatment tanks managing these
 wastewaters, is directly related to the
 fact that current regulatory programs do
 not appear to adequately address the
 type of air releases from these units that
 showed risk in our analysis.
  Waste volume is part of our risk level
 calculations. As explained in section
III.D., risk is projected based on the
volume of waste managed under each
modeled waste management scenario.

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Federal Register/Vol.  64, No.  164/Wednesday,  August  25,  1999/Proposed Rules
 We note that there is a significant
 volume of chlorinated aliphatic
 wastewater generated annually (11.5
 million metric tons). Our risk
 assessment methodology also accounts
 for the co-occurrence of hazardous
 constituents in any particular waste.
 Section IlI.D.l.b. discusses the number
 of potential constituents of potential
 concern identified in each wastestream.
 A more detailed discussion of the
 constituents of potential concern
 detected in each wastestream analyzed
 is provided in the Risk Assessment
 Technical Background Document for the
 Chlorinated Aliphatics Listing
 Determination for this rule, which is
 available in the docket for today's rule.
   With regard to the remaining factor in
 § 261.11 (a) (3), no actual damage
 incidents have been observed
 (§ 261.11 (a) (3) (ix)). However, the risk
 levels indicated, large waste volumes,
 certainty of waste characterization and
 risk assessment, coverage by other
 regulatory programs, and accounting for
 co-occurrence of constituents in the
 waste, outweigh the lack of observed
 damages. This is because the potential
 risks associated with this wastestream
 would be long term. Such risks are very
 difficult to directly attribute to any
 particular cause and can result even  in
 the absence of observable releases. Our
 failure to observe damages incidents
 does not mean they have not occurred
 or that risks are not being'imposed upon
 surrounding populations. RCRA is
 designed to be a prospectively-
 protective statute and the Agency need
 not wait for actual damages to be
 observed.
   As discussed previously, the risk
 assessment addresses nine of the listing
 criteria in 40 CFR 261.11. EPA believes
 th? risks resulting from our analysis
 represent plausible management of
 these wastes (§ 261.11 (a) (3) (vii)) using
 reasonable assumptions for treatment of
 wastewaters in tanks. In addition, the
 risk analysis was developed using actual
 analytical data. However, the Agency
 still recognizes that sources of
 uncertainty could be contributing to an
 overestimation of risk. The Agency
 points out that risk modeling results
 show risks at significant levels only in
 cases where sensitive input parameters
 are assumed to represent high-end
 circumstances.
  Finally, the Agency did not model
 wastewaters that are already defined as
 hazardous wastes (i.e., wastes mixed
 with or derived-frpm other existing
 listed wastes, or exhibiting a
 characteristic of hazardous waste),
 because we assume these wastes are
already, and will continue to be.
properly handled as hazardous. On-site
                        injection of wastewaters to a permitted
                        UIC well also was not modeled.
                        Although information obtained from the
                        RCRA Section 3007 questionnaire and
                        other publicly available information
                        indicate that some chlorinated aliphatic
                        manufacturing facilities manage
                        wastewaters via underground injection,
                        the majority of these wastewaters
                        currently are managed as hazardous
                        wastes and injected into Class I
                        permitted hazardous waste UIC wells in
                        accordance with approved no-migration
                        petitions. Only one facility manages
                        chlorinated aliphatic wastewaters as
                        non-hazardous waste and injects the
                        wastewaters in a permitted UIC well.
                          Although we have proposed to list
                        this wastestream, we recognize that our
                        estimates of the risks associated with
                        this wastestream are within the range in
                        which the Agency has stated it may
                        consider other factors in deciding
                        whether to list a waste. EPA invites
                        comment as to whether there are other
                        factors EPA should consider that would
                        further support a final decision to list
                        this waste or that would support a
                        conclusion that EPA should not list  this
                        waste. EPA has, for example, asked for
                        comment earlier in section D.l.f.ii.
                        regarding whether to consider
                        population risk.

                        ii. What is the Scope of Today's
                        Proposed Listing Determination for
                        Chlorinated Aliphatic Wastewaters?
                         The scope of today's proposed listing
                        includes all wastewaters generated by
                        chlorinated aliphatic production
                        processes, except for wastewaters
                        generated from the production of vinyl
                        chloride monomer using mercuric
                        chloride catalyst in an acetylene-based
                        process (VCM-A process). These
                       wastewaters were evaluated separately
                        (see section III.E.l.b.). The listing
                       description for chlorinated aliphatic
                       wastewaters is as follows:
                       K173  Wastewaters from the production of
                           chlorinated aliphatic hydrocarbons,
                           except wastewaters generated from the
                           production of vinyl chloride monomer
                           using mercuric chloride catalyst in an
                           acetylene-based process. This listing
                           includes wastewaters from the
                           production of chlorinated aliphatic
                           hydrocarbons having carbon chain
                           lengths ranging from one to and
                           including five, with varying amounts
                           and positions of chlorine substitution.

                       iii. What Is the Proposed Regulatory
                       Status of Sludges Derived From the
                       Treatment of Wastewaters Covered by
                       the Proposed Listing Determination?
                        The Agency is proposing to amend
                       the current RCRA regulations so that
                       wastewater treatment sludges generated
                       from the treatment of wastewaters
  proposed to be listed as hazardous
  waste K173 will not be classified as
  hazardous waste as a result of the
  "derived-from" rule (40 CFR
  261.3(c)(2)(i)). The proposed
  amendment to the derived from rule
  will exempt sludges'derived from the
  processing or management of proposed
  K173, as long as the wastes would not
  otherwise be defined as hazardous
  waste, absent the proposed  K173 listing.
  As presented elsewhere in today's
  proposed rule, EPA has studied
  wastewater treatment sludges from the
  chlorinated aliphatics industry and
  made independent hazardous waste
  listing determinations for several
  categories of sludges. These
  independent  evaluations of the potential
  risks associated with wastewater
  treatment sludges derived from today's
  proposed K173 wastewaters supercede
  any presumed risk imparted by
  application of the derived-from rule  in
  this instance. These risk evaluations
  logically should take precedent over the
 application of the derived-from rule,
 which presumes risk absent any
 information on toxicity of the treatment
 residual. The Agency points out,
 however, that sludges and other
 residuals generated as a result of
 managing chlorinated aliphatic
 wastewaters that carry waste codes
 other than K173, and residuals that
 otherwise are listed hazardous wastes
 (or exhibit a characteristic of hazardous
 waste) remain hazardous wastes.
   EPA is today proposing to add a new
 paragraph (E)  to the derived-from
 regulations at 40 CFR 261.3(c)(2)(ii) to
 make clear that wastewater treatment
 sludges derived-from treating K173
 wastewaters will not be hazardous
 waste via the derived-from rule.

 iv. What Comments Is EPA Specifically
 Requesting on the Proposed Listing of
 Chlorinated Aliphatic Wastewaters?
  The Agency requests comments on
 the proposed listing of wastewaters from
 the production of chlorinated aliphatic
 hydrocarbons, specifically, how would
 specific areas of potential uncertainty
justify a decision to list or not list these
 wastewaters as hazardous.

 v. How Does the Agency Propose To
 Address the Risks Associated With
 Chlorinated Aliphatic Wastewaters
 Affected by the Proposed Listing?
  Owners and operators of wastewater
treatment units, as defined in 40 CFR
260.10, are not required to obtain a
RCRA permit or comply with the
management standards of 40  CFR Parts
264 (permitted facilities) and 265
(interim status facilities) when
managing hazardous wastes in such

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                 Federal Register/Vol. 64, No.  164/Wednesday,  August 25, 1999/Proposed Rules
                                                                       46503
  units (40 CFR 264.1(g)(6) and
  265.1(c)(10)). Section 260.10 defines a
  wastewater treatment unit as a device
  which (1) is a part of a wastewater
  treatment facility that is subject to
  regulation under §402 or §307 (b) of the
  Clean Water Act; (2) receives and treats
  or stores an influent wastewater that is
  a hazardous waste, generates and
  accumulates a wastewater treatment
  sludge that is a hazardous waste, or
  treats or stores a wastewater treatment
  sludge that is a hazardous waste; and (3)
  meets the definition of a tank or tank
  system.
    The results of the Agency's risk
  assessment for chlorinated aliphatic
  wastewaters shows significant risks due
  to air emissions of dioxins from
  uncovered and aerated biological
  treatment tanks. The Agency's proposed
  listing determination for these
  wastewaters alone will not address the
  risk pathway of concern, due to the
  regulatory exemption for wastewater
  treatment units. To address the risks
  associated with the management of
  proposed  K173 chlorinated aliphatic
  wastewaters, the Agency is proposing to
  require that wastewater treatment units
  used to treat chlorinated aliphatic
  wastewaters comply with specific
  requirements in 40 CFR Parts 264 and
  265, subpart CC (Air Emission
  Standards for Tanks,  Surface
 Impoundments, and Containers). The
 Agency's objective is to require air
 emission controls for wastewater
 treatment tanks managing these
 wastewaters to prevent the release of
 dioxin vapor emissions to the
 environment. These proposed
 requirements would be enforceable
 requirements of RCRA subtitle C.
   By this limited proposal to change the
 exemption for wastewater treatment
 tanks that are used to treat chlorinated
 aliphatic wastewaters, which  is based
 only on a risk assessment of certain
 kinds of tanks used to treat these
 specific wastewaters, EPA is not
 reopening any other aspect of the
 wastewater treatment unit exemption.
 What Type of Requirements is EPA
 Proposing To Prevent Air Releases From
 These  Tanks?
  EPA considered simply requiring that
 the tanks be "covered" to prevent air
 releases of dioxins from K173
 wastewaters. However, it became
 apparent that such a simplified
 approach might not provide adequate
guidance to the regulated community on
how to ensure they are complying with
this type of performance standard. The
Agency determined that the existing
requirements for controlling air
emissions from hazardous waste tanks,
  in subpart CC of 40 CFR Parts 264 and
  265, could be used with some
  modifications to meet the goal of
  controlling air emissions from tanks
  managing proposed K173 wastewaters.
    Currently, the 40 CFR 264/265
  subpart CC requirements address
  volatile organic (VO) emissions from
  hazardous waste managed in tanks,
  surface impoundments, and containers.
  Therefore, many of the provisions in
  subpart CC (e.g., the VO concentration
  threshold of 500 parts per million by
  weight for determining applicability of
  the Subpart CC requirements) are not
  appropriate for dioxin emissions.
  However, other provisions (namely, the
  technical standards for covering tanks
  and controlling emissions in Sections
  264.1084 and 265.1085) are appropriate
  for controlling air emissions from
  wastewater treatment tanks managing
  K173 wastewaters. Therefore, EPA is
  proposing to amend the subpart CC
  requirements (described in more detail
  below) so that specific technical
  standards already in subpart CC for tank
  emissions apply to tanks managing
  K173 wastewaters. (The Agency notes
  that the standards being proposed today,
  if finalized, will  apply irrespective of
  the VOC content of the wastewater.) We
  also recognize that dioxin levels vary
  among generators, and thus are
  proposing a trigger level for dioxins
  below which compliance with subpart
  CC is not required. This is because our
 analytical data indicate that there is a
 range of dioxin levels in the chlorinated
 aliphatic wastewaters.30 In  particular,
 two samples contained TCDD TEQ
 levels that were four orders of
 magnitude lower than both the
 maximum and average TCDD TEQ
 concentrations.
 How Did EPA Develop the 2,3,7,8-TCDD
 TEQ Limit for Wastewaters?
   EPA's first step in establishing a
 concentration limit for dioxins was to
 determine whether we should set the
 limit as a 2,3,7,8-TCDD TEQ (TCDD
 TEQ) concentration, or as a set of
 individual limits for each of the specific
 dioxin congeners. We decided to set the
 limit as a 2,3,7,8 TCDD TEQ
 concentration. In  making this decision,
 we considered the analytical results
 from the six dedicated chlorinated
 aliphatics headworks wastewater
 samples collected during the record
 sampling effort (see Section III.D.l.b.).
We determined that wastewaters from
the production of chlorinated aliphatic
chemicals do not carry a distinct
  30 See Appendix B of "Listing Background
Document for the Chlorinated Aliphatics Listing
Determination."
  congener "fingerprint," that is, certain
  congeners are not consistently more
  prevalent in samples of chlorinated
  aliphatics wastewaters than other
  congeners. Because the congener
  composition of chlorinated aliphatic
  wastewaters is not consistent or distinct,
  setting limits on a congener-specific
  basis likely would be overly-restrictive
  for some facilities. Specifically, the limit
  set for a given congener would need to
  be protective in cases where a number
  of different congeners contribute to the
  wastewater's dioxin toxicity or risk
  (thereby requiring that lower limits be
  set for each congener to ensure that the
  combined emissions of each congener
  would not generate unacceptable risk).
  Such limits might be overly restrictive
  for those wastewaters with a dioxin
  composition that is dominated by a
  much smaller number of congeners.
  Moreover, setting the dioxin limit as a
  TCDD TEQ is consistent with the
  approach we have taken with other
  regulations, such as the Water Quality
  Guidance for the Great Lakes System, 40
  CFR Part 132, Appendix F.
   After considering options for setting
  the TCDD TEQ limit, we chose to base
  the TCDD TEQ limit on the lowest
  TCDD TEQ concentration measured in a
  dedicated wastewater sample for which
  a high end deterministic risk estimate is
  1 x 10~5. This concentration is 0.6 ng/
  L, calculated using the TEFs developed
  by the World Health Organization, and
 corresponding to the TCDD TEQ
 concentration for EPA's sample no. PL-
 02.  (The TCDD TEQ concentration based
 on the I-TEFs is 0.7 ng/L. See section
 III.D.l.g.ii. for an explanation of the
 TEFs). The high end deterministic risk
 estimate was based on the evaluation of
 a farmer scenario (see section III.D. 1 .f.)
 in which the exposure duration of the
 farmer was set at its high end value,
 48.3 years. For the purpose of
 establishing the TCDD TEQ limit, we
 did  not set any additional values at high
 end. We used the "single high end"
 approach to account for sources of
 uncertainty in the risk analysis and our
 understanding that not all of the
 underlying assumptions of the analysis
 may be relevant to any one chlorinated
 aliphatics facility. For example, not all
 facilities may operate the type of aerated
 biological treatment tank that was
 modeled, grazing of cattle may not occur
 in the vicinity of all facilities on the
 centerline of the contaminant plume
 (the  farmer's risk primarily is due to the
 ingestion of contaminated beef and
 dairy products). For reference, the adult
resident's "single high end" risk is 1 x
 10-9 when the wastewater concentration

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Federal Register/Vol. 64,  No.  164/Wednesday, August 25,  1999/Proposed Rules
 is 0.6 ng/L (based on meteorological
 location as a high end parameter).
   "The 1 x ld~5 risk result for the farmer
 Is based on predicted long-term average
 exposures assuming a  wastewater TCDD
 TEQ concentration of 0.6 ng/L. as well
 as certain other environmental and
 exposure factors. This means that over
 tjje long term, the receptor is protected
 at the 1 x 10~5 level when, on average,
 t£e TCDP TEQ concentration in the
 wastewater is 0.6 ng/L. That is, it is
 implicit in the analysis that even if there
 are excursions of the wastewater TCDD
 TEQ concentration above 0.6 ng/L, an
 individual is still protected at the 1 x
 10 ~* risk level if on average the
 wistewater TCDD TEQ concentration is
 0.6 ng/L. Today EPA is proposing to set
 the TCDD TEQ limit for wastewaters at
 1 ng/L. Setting the limit at 1 ng/L
 accounts for the fact that we believe
 facilities who comply with the
 requirement that the TCDD TEQ
 concentrations of their wastewaters not
 exceed 1 ng/L will on average maintain
 wastewater TCDD TEQ concentrations
 of approximately 0.6 ng/L or below.
 EPA is proposing that wastewater
 treatment tanks managing proposed
 K173 wastewaters, where the TCDD
 TEQ concentration  in the wastewater is
 greater than or equal to 1 ng/L, comply
 with specific air emission control
 regulations, as described in more detail
 below.
   It is important to  note that the 1 ng/
 L trigger level described here for
 implementing the proposed tank cover
 requirement is not a concentration
 below which the wastewater does not
 meet the K173 listing. This proposed
 listing follows what can be described as
 the traditional approach EPA has taken
 for hazardous waste listings (i.e., if a
 particular facility's waste meets the
 listing description, it is listed regardless
 of the concentration of constituents or
 waste management practice employed).
 While we are proposing to list
 wastewaters following this traditional
 approach, today's rule does establish a
 concentration level  for  wastewaters that
 reflect the Agency's concern for dioxin
 managed in tanks  within this industry.
 We seek comment on the alternative of
 using this level as criteria for the listing
 itself. The Agency could finalize a
 concentration based listing based on the
 1 ng/L trigger level instead of the
 traditional listing proposed today. The
 Agency also seeks comment on whether
 this concentration-based listing
approach should be  implemented in the
same manner as is described in this
notice (i.e., where  the I ng/L
concentration is a  trigger for requiring
tank covers), or alternatively, whether it
would be more appropriate to apply the
                         implementation approaches described
                         in the July 23, 1999 rulemaking for the
                         dyes and pigments industry (placed in
                         the docket for today's rulemaking for
                         convenience).

                         How Will These Air Emission Controls
                         Be Implemented?

                           As described below, we are proposing
                         that generators of K173 who manage
                         these wastes in tanks comply with
                         certain air emission control
                         requirements, including covering their
                         tanks, unless the results of testing the
                         wastewater influent to the tank indicate
                         that the dioxin concentrations are below
                         the 1 ng/L trigger level. Our proposed
                         approach consists of the following
                         elements:

                          • Each wastewater treatment tank
                         managing K173 that is not compliant with 40
                         CFR sections 264.1084/265.1085 of subpart
                         CC must be assessed to determine  whether
                         dioxin levels in the influent to the tank
                         exceed the trigger level.
                          • For the purposes of this listing, the
                         headworks of the wastewater treatment
                         system is assumed to be at a location directly
                         after steam stripping. If a facility does not
                         utilize steam stripping, the wastewater
                         treatment system headworks is assumed to be
                         the first tank in which wastewaters are
                         combined, accumulated or treated after
                         leaving the chlorinated aliphatics production
                         process.
                          • Tanks that are fully compliant with
                        sections 264.1084/265.1085 of 40 CFR
                        subpart CC would not be subject to waste
                        analysis, record keeping and notification
                        requirements proposed in today's rule to be
                        added to 40 CFR 265.1080(f)(l)-(5),
                        described below.
                          • Once the facility has established that
                        TCDD TEQ levels do not exceed the trigger
                        level for a specific tank, the facility can
                        assume that the TCDD TEQ levels for all
                        downstream tanks also are below the trigger
                        level.
                          • The facility must develop a waste
                        analysis plan prior to sampling and analysis
                        to ensure that the measurements are
                        sufficiently sensitive, accurate and precise to
                        demonstrate compliance, as described further
                        below. We suggest that the waste analysis
                        plan be developed in accordance with
                        Agency guidance.31
                          • The initial assessment must be
                        conducted by the effective date of the rule.
                         31 Chapter Nine of "Test Methods for Evaluating
                        Solid Waste, Physical/Chemical Methods" (SW-
                        846) addresses the development and
                        implementation of a scientifically credible sampling
                        plan. Chapter One of SW-846 describes the basic
                        elements to be included in a Quality Assurance
                        Project Plan (QAPP). as well as information
                        describing basic quality assurance (QA) and quality
                        control (QC) procedures. Chapter Two of SW-846
                        aids the analyst in choosing the appropriate
                        methods for samples, based upon sample matrix
                        and the analytes to be determined. Other
                        appropriate sources may also be used, including
                        those issued by recognized national voluntary
                        standards setting organizations, e.g., ASTM, etc.,
                        http://www.epa.gov/ncepihom/Catalog/EPASW-
                        846.3.4A.html
 If the trigger level is exceeded, compliance
 with the applicable sections of 40 CFR 264/
 265 subpart CC must be accomplished within
 one year of the effective date. Alternatively,
 the facility may implement process changes
 to reduce the TCDD TEQ level below the
 trigger level, and repeat the initial assessment
 to demonstrate that levels are now below the
 trigger level, within the same one year time
 frame.
   • If it is determined that the TCDD TEQ
 concentration measured during the initial
 assessment is below the trigger level, re-
 assessment would be required '(1) as a result
 of any process changes that would impact
 dioxin wastewater levels, and  (2) annually.
   • If the trigger level is not exceeded, the
 facility must submit a one-time notification
 and certification.
   • The facility must maintain records on
 site.

 Sampling and Analysis
   In designing the sampling program,
 the facility must consider any expected
 fluctuations in concentrations over time.
 The sample design should be described
 in the waste analysis plan, which must
 be retained in the facility's files. The
 sample design must be adequate to
 determine that the level of TCDD TEQ
 in the wastewater is above or below the
 1  ng/L at a 95 percent upper confidence
 limit around the mean. This approach is
 being used in the comparable fuels final
 rule (June 19, 1998; 63 FR 33782). See
 also Guidance for Data Quality
 Assessment—Practical Methods for Data
 Analysis, EPA QA/G-9, January 1998,
 EPA/600/R-96/084. Under this
 approach, EPA is not specifying a
 specific number of samples, because the
 number of samples required to
 demonstrate that the wastewater dioxin
 concentration is below 1 ng/L at the 95
 percent upper confidence limit depends
 on how close the actual concentration is
 to the regulatory limit and on the
 variability of the waste. EPA is
 proposing that the samples used to
 demonstrate compliance be grab
 samples collected within a time period
 that will accurately account for
 potential variability in the wastestream,
 including potential variabilities
 associated with batch and continuous
 processes. If properly stored, the
 holding time for unprocessed aqueous
 samples of dioxins/furans (which can be
 found in the Sample Collection,
 Handling and Preservation section of
 Method 8290) allows for multiple
 samples to be collected and be available
 should additional analysis be required
 to achieve the data quality objective of
 determining compliance with the 1 ng/
 L limit at a 95% upper confidence limit
around the mean.
  EPA also is proposing an alternative
sample design criteria. The alternative
approach is to set a maximum

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                 Federal Register/Vol.  64.  No. 164/Wednesday, August 25,  1999/Proposed Rules
                                                                       46505
  quantitation value as an alternative to
  the use of the 95% upper confidence
  limit around the mean. Under this
  approach, the Agency is proposing that
  the analytical quantitation limits should
  be sufficient to calculate a meaningful
  TCDD TEQ for comparison to the 1
  ng/L trigger level. Our experience with
  this matrix is that quantitation at or
  below 0.05 ng/L should be routinely
  achievable, therefore we are proposing
  that the selected analytical method
  achieve a precision of at least 30 percent
  relative standard deviation at a
  calibration level of 0.05 ng/L and a
  recovery of greater than or equal to 70
  percent32 (we note that if isotope-
  dilution methods are used, recovery is
  not an issue,  since this method is self-
  correcting for recovery.) Under this
  approach, EPA is specifying  that a
  minimum of four grab samples be
  collected within a 24-hour time period.
  The Agency notes that although we are
  considering setting a lower calibration
  standard for the measurement method
  as an alternative to the 95 percent upper
  confidence limit around the mean
  standard, the regulatory language
  included with today's proposal reflects
  only the preferred option.
   Generators may not use process
 knowledge to determine whether or not
 the 1 ng/L TCDD TEQ trigger level has
 been exceeded for the first tanks in the
 wastewater treatment system where
 constituent concentrations are likely to
 be highest. However,  once the facility
 has established that the trigger level is
 not exceeded in the influent to a given
 tank, the facility may use process
 knowledge to determine that  dioxin
 levels in wastewaters managed in
 subsequent downstream tanks also will
 not exceed the trigger level.
   We are proposing that the generator
 maintain documentation of the: (1)
 detailed standard operating procedures
 (SOPs) for the sampling and analysis
 protocols that were employed; (2)
 sensitivity and bias of the measurement
 process; (3) precision  of the analytical
 results for each batch  of waste tested;
 and (4) analytical results.
  It is the responsibility of the generator
 to ensure that the sampling and analysis
 is unbiased, precise, and representative
 of the tank influent. To show that a tank
 is not subject to the specific Subpart CC
 requirements applicable to K173
  32 Recent recovery is from an EPA Memorandum
from Barnes Johnson, Director of the Economics,
Methods, and Risk Assessment Division, to James
Berlow, Director of the Hazardous Waste
Minimization and Management Division, regarding
the Office of Solid Waste's (OSW) standing policy
on the Appropriate Selection and Performance of
Analytical Methods for Waste Matrices Considered
to be "DifFicult-to-Analyze." January 31.1996.
  wastewaters, a generator must
  demonstrate that: (1) the maximum
  TCDD TEQ in the tank influent does not
  exceed the 1 ng/L trigger level; and (2)
  the analysis could have detected the
  presence of the CDD/CDF congeners at
  or below the trigger level.
    We are not requiring the use of SW-
  846 methods to comply with these
  requirements. We are proposing .to allow
  the use of alternative methods to those
  included in SW-846, so long as the
  selected methods meet the following
  performance based criteria.
    The Agency will consider the analysis
  adequate to demonstrate that the trigger
  level of 1 ng/L is not exceeded if an
  analysis in which TCDD (as a surrogate
  for all of the CDD/CDF congeners)
  spiked at the trigger level indicates that
  the analyte is present at that level
  within analytical method performance
  limits (e.g., sensitivity, bias and
  precision).  To determine the
  performance limits for a method, EPA
  recommends following the quality
  control (QC) guidance provided in
  Chapters One and Two of SW-846, and
  the additional QC guidance provided in
  Method 8290.
  respond to any comments submitted
  regarding the exemption.

  b. How Is EPA Proposing to Regulate
  VCM-A Wastewaters?
    EPA is proposing not to list as
  hazardous wastewaters generated from
  the production of VCM using mercuric
  chloride catalyst in an acetylene-based
  process. This wastestream already is
  defined as hazardous waste due to the
  fact that it exhibits the toxicity
  characteristic.
 vi. What Comments Is EPA Specifically
 Requesting on the Proposed Approach
 for Controlling Dioxin Air Emissions?
   The Agency requests comment on the
 proposal to add air emission control
 requirements for tanks used to manage
 chlorinated aliphatic wastewaters. In
 addition, the Agency requests comment
 on whether the technical standards in
 264.1084/265.1085 will address the
 risks associated with vapor emissions
 from these units. EPA requests comment
 on the proposed 1 ng/L TCDD TEQ
 concentration limit in wastewater that
 triggers application of the air emission
 control requirements, and on the testing
 and recordkeeping requirements for
 implementing this standard.
 Specifically, EPA is requesting comment
 on comparing the regulatory limit to a
 sample mean at the 95% upper
 confidence limit, versus a maximum
 sample value with the sensitivity (as
 demonstrated by the lower calibration
 standard), precision, and recovery
 (unless using the isotope-dilution
 method) described in today's proposal.
  In addition, we request comment on
 whether or not there are other types of
 standards and/or other factors the
 Agency should consider in setting
 standards for wastewater treatment
 units used to manage chlorinated
aliphatic wastewaters. The Agency is
not reconsidering or requesting
comment on the wastewater treatment
unit exemption and does not intend to
  i. What Information Led EPA To
  Propose Not to List as Hazardous
  Wastewaters From the VCM-A Process?
    EPA knows of only one facility in the
  United States that operates an acetylene-
  based VCM production process, which
  uses mercuric chloride catalysts in the
  production of VCM. The management of
  spent mercuric chloride catalyst used in
  the VCM-A production process results
  in the generation of a wastewater
  containing mercuric chloride, as well as
  vinyl chloride. The wastewater
  treatment system is operated in a batch
  process fashion in tanks, and is
  designed to convert the mercuric
  chloride  present in the process
  wastewaters to an much less soluble
  mercuric sulfide. The mercuric sulfide
  is precipitated during the treatment
  process, dewatered, and collected for
  off-site disposal. The remaining
 wastewaters are discharged directly
 under an NPDES permit. Due to the fact
 that this wastewater is managed in a
 single, dedicated wastewater treatment
 system associated with a unique
 production process, and the presence of
 mercury in relatively high
 concentrations (which is not found in
 other chlorinated aliphatic
 wastewaters), the Agency decided to
 consider this wastestream separately in
 our investigation of the wastes
 generated by the chlorinated aliphatic
 hydrocarbons manufacturing industry.
   According to the RCRA Section 3007
 survey response, the facility generates
 and discharges approximately 22,200
 metric tons (5.86 million gallons) of
 wastewater from the VCM-A process
 each year. The identified constituents of
 concern in this wastestream include
 mercury and vinyl chloride. In addition,
 dioxins are present in these
 wastewaters. EPA analyzed one sample
 of this wastewater in 1996 in support of
 this listing determination. The
 analytical results showed the
 wastewaters contained 8.60 mg/L
 mercury, and 0.680 mg/L vinyl chloride.
The analytical results for the split
sample taken by the facility were 6.78
mg/L mercury, and 1.38 mg/L vinyl
chloride. The results exceed the toxicity.

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Federal  Register/Vol. 64, No.  164/Wednesday, August 25, 1999/Proposed Rules
 characteristic regulatory levels of 0.2
 mg/L for mercury and 0.2 mg/L for vinyl
 chloride, Dioxins also were detected in
 trje VCM-A wastewaters, however, the
 concentration was several orders of
 magnitude lower than levels found in
 other wastewaters generated from other
 chlorinated aliphatic manufacturing
 processes (i.e., 0.0022 ng/LTEQ/TCDD).
   Based upon EPA's one record sample,
 this wastestream already is identified as
 a hazardous waste due to the fact that
 the waste exhibits the toxicity
 characteristic (TC). The constituents of
 significant concern in the VCM-A
 wastewaters (i.e., mercury and vinyl
 chloride) already are regulated under
 the TC, therefore, the TC adequately
 defines this wastestream as hazardous.
 Further, the facility's dedicated
 wastewater treatment system was
 designed and optimized expressly for
 the removal of mercury from mercuric
 chloride catalysts to comply with the
 Clean Water Act. In addition, given the
 fact that EPA's record sample was over
 40 times above the TC limit for mercury,
 it is highly probable that these
 wasetwaters routinely contain levels of
 mercury which cause this wastestream
 to be defined as characteristically
 hazardous waste. As mentioned
 previously, the criteria in 40 CFR 261.11
 (a) (3) for evaluating whether or not a
 solid waste Is a hazardous waste
 provide that EPA should consider how
 the waste (and potential risk) is affected
 by other regulatory programs (i.e.,
 261.11 (a) (3) (x)). In the case of the VCM-
 A wastewaters, EPA notes that our
 decision to propose not to list this
 wastewater as hazardous is based in
 large part on the fact that the waste
 already is defined as a hazardous waste
 because it exhibits the toxicity
 characteristic. We have, accordingly,
 determined that there is no regulatory
 benefit in listing this wastewater as
 hazardous, particularly when
 considering that the volume of
 Wastewater generated by the single
 facility using the acetylene-based VCM
 production process is relatively small
 (22,200 metric tons annually) compared
 to the volumes of wastewaters generated
 in other chlorinated aliphatic
 wastewater treatment systems (11.5
 million metric tons annually).
  In addition, any risks associated with
 the management and disposal (i.e.,
 direct discharge) of the wastewaters are
 addressed by other environmental
 regulations. With  respect to the
 discharge of the wastewater, the facility
 treats and discharges die wastewater in
 compliance with the conditions of a
 NPDES permit. Regarding any air
emissions of vinyl chloride from these
wastewaters, vinyl chloride is a
                        hazardous air pollutant, therefore the
                        facility is subject to the National
                        Emissions Standards for Hazardous Air
                        Pollutants (NESHAP) requirements
                        specific to vinyl chloride emissions (40
                        CFR Section 61.65), as well as the
                        Hazardous Organic NESHAP for the
                        synthetic and organic chemical
                        manufacturing industry sector (40 CFR
                        Part 63, subpart G) (59 FR 19468, April
                        22, 1994). For these reasons, the Agency
                        is proposing not to list VCM-A
                        wastewaters as hazardous waste.
                         Sludges generated by the wastewater
                        treatment process are disposed of in an
                        off-site hazardous waste (subtitle C)
                        landfill. EPA conducted a separate
                        investigation of these sludges. The
                        results of this investigation and our
                        listing determination for the  VCM-A
                        wastewater treatment sludges are
                        summarized in section III.E.3. further
                        below.

                        2. EDC/VCM Wastewater Treatment
                        Sludges
                       a. How Is EPA Proposing To  Regulate
                       EDC/VCM Wastewater Treatment
                       Sludges?

                         EPA is proposing to list as  hazardous
                       sludges generated from treating
                       wastewaters associated with  the
                       manufacture of ethylene dichloride
                        (EDC) and vinyl chloride monomer
                       (VCM). This wastestream meets the
                       criteria set out at 40 CFR 261.11 (a) (3) for
                       listing a waste as hazardous and is
                       capable of posing a substantial present
                       or potential hazard to human health or
                       the environment when managed in land
                       treatment units. The Agency  identified
                       risks of concern associated with one
                       management practice, on-site land
                       treatment. In our risk assessment of
                       these wastes, the exposed individuals of
                       concern were the farmer, child of
                       farmer, and the fisher receptors. The
                       contaminants of concern are dioxin and
                       arsenic.
                         As discussed in section III.D. 1 above,
                       our analyses identified health risks from
                       the land treatment of the EDC/VCM
                       wastewater treatment sludges due to
                       airborne releases and subsequent
                       deposition and food chain
                       contamination from dioxin. Surface
                       erosion due to runoff also contributes to
                       risk from dioxin. Marginal risks from
                       arsenic were identified for the land
                       treatment unit groundwater ingestion
                       exposure pathway. We also modeled a
                       landfill management scenario; our risk
                       assessment showed no significant risk
                       from dioxin. and only marginal risk
                       from arsenic associated with the
                       groundwater pathway.
 b. What Information Led EPA To
 Propose To List as Hazardous EDC/VCM
 Wastewater Treatment Sludges?
   The results of the RCRA Section 3007
 chlorinated aliphatic industry survey
 show that approximately 104,606 metric
 tons of wastewater treatment sludge is
 generated from the treatment of
 wastewaters at chlorinated aliphatic
 plants that manufacture VCM and/or
 EDC. One facility accounts for 74
 percent of the total volume -of
 wastewater treatment sludge
 generated.33 Of the total volume of
 wastewater treatment sludges generated
 at plants manufacturing EDC/VCM and
 identified through the survey, 6,757
 metric tons (6 percent) currently are
 already'defined as hazardous waste.
   EDC/VCM wastewater treatment
 sludges are generated at 12 facilities.
 The Agency notes that these sludges are
 not always generated from treating
 wastewaters produced exclusively from
 EDC  and/or VCM manufacturing
 processes. Rather, sludges are
 sometimes generated in wastewater
 treatment systems that treat wastewaters
 from manufacturing processes
 producing a variety of chlorinated
 aliphatic and non-chlorinated aliphatic
 products. Wastewaters from multiple
 processes are combined prior to
 wastewater treatment. The Agency
 points out that the listing determination
 proposed today for EDC/VCM
 wastewater treatment sludges affects the
 total quantity of the sludges generated
 by a wastewater treatment system that
 accepts influent from any process
 manufacturing EDC and/or VCM. EPA
 has made this clear by including sludges
 from  commingled EDC/VCM wastewater
 and other wastewater within the scope
 of the listing, although EPA believes this
 would have been the correct
 interpretation of the  listing even absent
 the clarifying language.
   The management scenarios selected
 for risk assessment were chosen based
 upon the waste management practices
 known to be practiced by the
 chlorinated aliphatic industry for non-
 hazardous sludges. Based on survey
 results, these practices are:
   • On-site land treatment (one
 facility),
   • On-site disposal  in a non-hazardous
 landfill (two facilities),
   • On-site co-disposal in a hazardous
 waste landfill (one facility), and
   • Off-site disposal  in a subtitle D
 landfill (7 facilities).
  As explained earlier,  EPA modeled
 risks from two management scenarios,
  33 Only one (1) percent of the wastewaters at this
facility are generated from the manufacturing of
EDC/VCM.

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                 Federal Register/Vol. 64, No.  164/Wednesday, August 25.  1999/Proposed Rules
                                                                         46507
  an off-site non-hazardous municipal
  landfill, and a land treatment unit. The
  management practices of most concern
  (landfills and land treatment) were
  assessed for this waste. Other non-
  hazardous waste management practices
  currently are not used by industry and
  would not serve as an appropriate basis
  for listing the waste as hazardous, In the
  case of the management practices
  employed by this industry, we are
  confident that the risk estimates from
  modeling an off-site non-hazardous
  waste landfill scenario also are
  representative of the potential risks
  associated with the management of
  EDC/VCM wastewater treatment sludges
  in on-site landfills. This is because
  information provided in facility
  responses to the RCRA Section 3007
  questionnaire indicate that EDC/VCM
  wastewater treatment sludges are co-
 • disposed with other industrial non-
  hazardous wastes in on-site landfills,
  therefore these units can be treated as
  off-site landfills (that receive a variety of
  wastestreams) rather than as monofills
  (that receive only one type of waste)
  with regard to the risk modeling
  approach employed.
   Land treatment The Agency's risk
  assessment of EDC/VCM wastewater
  treatment sludge showed risks of
  concern for the land treatment
  management scenario. The contaminant
  of greatest concern is dioxin. The
  exposure routes of concern are airborne
 releases and surface erosion from runoff
 which result in contamination of food
 products from nearby agricultural
 operations. The sludges present a
 hazard due to the fact that land
 treatment units are not covered and due
 to the potential absence of runoff
 controls. Land treatment results in a
 high-end  cancer risk for the farmer of
 2E-4 and a central tendency risk of 4E-
 6. EPA also performed a Monte Carlo
 analysis, and the results showed a risk
 for the farmer of 1E-4 at the 90th
 percentile, and 7E-6 at the 50th
 percentile. The high-end  deterministic
 risk falls within the risk range for which
 there is a presumption  for listing the
 waste as hazardous, consistent with
 guidance the Agency has used for
 determining that a waste  is hazardous
 (see 59 FR at 66077), i.e.,  the risks
 associated with management of EDC/
 VCM sludge in a land treatment unit are
 1E-4  or higher, and well above the 1E-
 5 listing benchmark. The  probabilistic
 results confirm that the high-end
 deterministic risk (2E-4) is above the
 90th percentile result (1E-4). The 1992
guidance (memorandum from the then
Deputy Administrator F. Henry Habicht
 "Guidance on Risk Characterization for
   Risk Managers and Risk Assessors")
   states that "[t]he 'high end' of the risk
   distribution, [generally the, area of
   concern for risk managers] is
   conceptually above the 90th percentile
   of the. actual (either measured or
   estimated) distribution. This conceptual
   range is not meant to precisely define
   the limits of this descriptor, but should
   be used by the assessor as a target range
   for characterizing 'high-end risk'."
   Therefore, a high-end estimate that falls
   Within the range (above the 90th
   percentile but still realistically on the
   distribution) is a reasonable basis for a
   decision. Therefore, EDC/VCM sludges
  managed in a land treatment unit pose
  risks that support a proposed listing
  determination for these wastes.
    As discussed previously, the risk
  assessment addresses nine of the listing
  criteria in 40 CFR 261.11. EPA believes
  the risks resulting from our analysis
  represent plausible management of
  EDC/VCM sludges (261.11 (a) (3) (vii))
  using reasonable assumptions for
  management in land treatment units. In
  addition, the risk analysis was
  developed using actual analytical data.
    Of lesser concern, but still within our
  discretionary risk range, are the
  potential health effects associated with
  arsenic in EDC/VCM wastewater
  treatment sludges that are managed in
  land treatment units. We found that
  arsenic presents some risk from
  potential releases to groundwater from
  the land treatment Unit. For the arsenic
  groundwater pathway, land treatment
  results in a high-end cancer risk of 1E-
  05 and a central tendency risk of 8E-07.
  However, the predicted time period for
  the peak arsenic concentration to reach
 a receptor well  is 1,500 years. In
 addition, our modeled leachate
 concentrations for arsenic result in
 predicted receptor well concentrations
 of 0.5 ppb (high end) and 0.2 ppb
 (central tendency). By comparison, the
 average background concentration of
 arsenic in rain derived from terrestrial
 air masses is 0.46 ppb.34 Therefore, EPA
 does not believe that the risk from
 arsenic in this waste is significant, as
 discussed below.
   Even though the high-end cancer risk
 from arsenic is within the general action
 level risk range (i.e., 1E-04 to 1E-06),
 the central tendency risk falls outside
 this range. Another factor that the
 Agency considered when evaluating the
 potential risks from arsenic in this
 wastestream is the significant period of
  MAndreae, M.O. 1980. Arsenic in Rain and the
Atmospheric Mass Balance of Arsenic. Journal of
Geophysical Research, v.85, pp. 4512-4518, as cited
in Welch, A.H., M.S. Lico. and J.L. Hughes. 1988.
Arsenic in Ground Water of the Western United
States. Ground Water, v.26, n.3, pp. 333-347.
   time it is predicted to take for the
   concentration of arsenic in a receptor
   well to reach the peak concentration
   level (i.e., 1,500 years). Given these
   factors, the Agency concludes that the
   risk posed from potential releases of
   arsenic in this wastestream when
   managed in land treatment units is
   marginal, and in itself does not warrant
   listing the waste as hazardous. The
   Agency therefore is proposing to list
   EDC/VCM wastewater treatment sludges
   based solely on the presence of dioxin
   and the potential risk associated with
   dioxin when this waste is managed in
   land treatment units. As outlined in the
  preamble to the Agency's proposed
  listing determination for wastes
  generated by the Dyes and Pigments
  Industry, listing determinations for
  wastestreams for which risks are
  calculated to be 1E-04 or higher are
  considered to pose a substantial present
  or potential hazard to human health and
  the environment and are listed as
  hazardous.
    Landfill. The Agency's risk
  assessment showed no significant risks
  associated with dioxin, and only
  marginal risk associated with potential
  groundwater releases of arsenic in the
  off-site landfill scenario. The risk
  assessment showed a high-end cancer
  risk from arsenic of 3E-05 and a central
  tendency risk of 9E-07. However, these
  risks levels are associated with a peak
  arsenic concentration  in a receptor well
  that is predicted to occur only after a
  period of 8,800 years. Predicted high
  end arsenic concentration at a receptor
  well is 1.4 ppb and the central tendency
 arsenic concentration in a receptor well
  is 0.2 ppb. This level of arsenic
 contamination is very close to average
 background exposure levels for arsenic.
 As mentioned above, the current
 average background concentration of
 arsenic in rain derived from terrestrial
 air masses is 0.46 ppb. Average
 background exposure to inorganic
 arsenic is 14 ug/day from food, and 5 to
 7 ug/L from water. EPA's modeling
 results indicate that the disposal of
 EDC/VCM sludge in an unlined landfill
 could (over a period of 8,800 years)
 increase the concentration of arsenic in
 groundwater in a downgradient well
 (102 meters from the landfill) by only
 1.4 ug/L and would add approximately
 2 ug/day of arsenic to the average daily
 exposure level (about 20 ug/day) for the
 highly exposed individual. Actual
 potential level of risk would be lower
 than those predicted by our modeling
 efforts, if the sludges are disposed in
 lined landfills.
   Given that the Agency's risk
assessment indicates potential risk
within our discretionary range

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 associated with a peak arsenic
 concentration in a receptor well that is
 predicted to occur only after a period of
 8,800 years, and given the absence of
 significant risk from any other
 constituents of concern, EPA concludes
 that EDC/VCM wastewater treatment
 sludges So not pose a significant risk
 when managed in landfills.
   Based upon the Agency's findings that
 EDC/VCM wastewater treatment sludges
 pose significant risks when managed in
 land treatment units but pose no
 significant risks when managed in
 landfills, the Agency is proposing a
 "contingent management listing" for
 this waste. EPA is proposing to list EDC/
 VCM wastewater treatment sludges as
 hazardous, unless the sludges are
 managed in landfills. Again,  the Agency
 is proposing this listing determination
 based upon the fact that our risk
 assessment results for the land
 treatment unit scenario indicate a level
 of risk of 2E-04, well above the 1E-5
 risk level the Agency uses as guidance
 in making listing determinations.
 c. Why Is EPA Proposing a Contingent
 Management Approach as Most
 Appropriate for EDC/VCM Wastewater
 Treatment Sludges?
   The Agency's analysis of the risks
 associated with EDC/VCM wastewater
 treatment sludges shows that one of the
 current waste management practices
 (land treatment) results in significant
 risk while the other primary
 management practice (disposal in
 subtitle D landfill) shows  little risk.
 Therefore, the Agency is proposing to
 list EDC/VCM wastewater treatment
 sludges as EPA Hazardous Waste
 Number K174, unless the  sludges are
 managed In a subtitle C or subtitle D
 landfill. The Agency believes that
 allowing the waste to continue to be
 managed under a low risk management
 scenario (i.e., subtitle D landfilling)
 outside of the subtitle C system achieves
 protection of human health and the
 environment, and that little additional
 benefit would be gained by requiring
 that all EDC/VCM wastewater treatment
 sludges be managed in accordance with
 RCRA subtitle C management standards.
 Given the Agency's finding that no
 significant risks are posed from
 managing EDC/VCM wastewater
 treatment sludges in a landfill, the
 Agency sees no reason to include
 sludges managed in this manner in the
scope of the hazardous waste listing.
 Additionally (and after consideration of
 the predicted risk differential between
land treatment and landfilling), because
 only one facility identified in the RCRA
Section 3007 Survey employs land
treatment for these wastes, this practice
                        is somewhat anomalous compared with
                        land disposal. It does not make sense to
                        apply a traditional listing approach (i.e.,
                        list all wastes regardless of management.
                        practice) based upon a practice
                        occurring at one facility, especially if a
                        more tailored listing can prevent this
                        risk.
                          A contingent management listing
                        approach is within EPA's statutory
                        authority. See Military Toxics Projects.
                        EPA, 146 F.3d 948 (D.C. Cir. 1998). The
                        Agency believes that making a listing
                        determination that is tailored to specific
                        waste management practices is
                        particularly appropriate under these
                        circumstances, where the management
                        practices identified are  clear and very
                        easily distinguished (such as the
                        difference between land treatment and
                        land disposal), and the differences in
                        risk presented by these practices are
                        clearly defined. In the case of EDC/VCM
                        wastewater treatment sludges, EPA
                        believes that an opportunity exists to
                        establish a conditional management
                        listing for these sludges that will reduce
                        the risks associated with unsafe waste
                        management practices, while not
                        imposing significant incremental costs
                        upon generators managing the wastes in
                        a manner that does not pose significant
                        risk. While disposal of EDC/VCM
                        wastewater treatment sludges in land
                        treatment units is projected  to pose
                        significant risks, the disposal of these
                        sludges in landfills does not result in
                        significant risks. This arises because the
                        constituent of most concern, dioxin/
                        TCDD, is relatively immobile in
                        groundwater. However,  risks from this
                        constituent can be significant if the
                        waste is managed in a manner that does
                        not control for airborne releases or
                        surface erosion from runoff,  both of
                        which are better controlled at landfills.
                        Therefore, EPA believes a contingent
                        management listing for this waste is a
                        preferable and permissible alternative to
                        simply listing all EDC/VCM  wastewater
                        treatment sludges as hazardous wastes.
                          The Agency's proposed listing
                        description for EDC/VCM wastewater
                        treatment sludges that will define this
 waste as hazardous unless the waste is
 managed in a landfill is as follows:
 K174  Wastewater treatment sludges from
    the production of ethylene clichloride or
    vinyl chloride monomer, unless the
    sludges meet the following conditions:
    (i) they are disposed~of in a subtitle C or
    D landfill licensed or permitted by the
    state or federal government;  (ii) they are
    not otherwise placed on the  land prior to
    final disposal; and (iii) the generator
    maintains documentation demonstrating
    that the waste was either disposed of in
    an on-site landfill or consigned to a
    transporter or disposal facility that
    provided a written commitment to
    dispose of the waste in an off-site
    landfill. Respondents in any action
    brought to enforce the requirements of
    subtitle C must, upon a showing by the
    government that the respondent
    managed wastewater treatment sludges
    from the production of vinyl chloride
    monomer or ethylene dichloride,
    demonstrate that they meet the terms of
    the exclusion set forth above. In doing
    so, they must provide appropriate
    documentation (e.g., contracts between
    the generator  and the landfill owner/
    operator, invoices documenting delivery
    of waste to landfill, etc.)  that the terms
    of the exclusion were met.

 d. How Will This Contingent
 Management Listing Be Implemented?
  Under this proposed listing, EDC/
 VCM wastewater treatment sludges will
 be hazardous wastes if managed by any
 method except disposal in a landfill.
 EPA has a clear  interest in ensuring that
 these sludges are in fact disposed  in a
 landfill, or else they would be listed
 hazardous waste at the point of
 generation. The  Agency also has an
 interest in making sure that accurate
 records are kept to facilitate
 enforcement.
  The Agency notes that based on the
 RCRA Section 3007 questionnaire   •
 results (which surveyed the universe  of
 chlorinated aliphatics production
 facilities in the United States), the
 predominant management practice used
 for these wastes  is disposal in a landfill,
 while one facility currently uses a land
 treatment facility. It is difficult for EPA
 to foresee a change in this well-
 established management practice.
 Therefore the Agency believes it is
 unlikely that these sludges will be sent
 to any type of facility other than a
 landfill, particularly if the approach
 proposed in today's rule is promulgated.
 Generators who choose to manage these
sludges at non-landfill facilities must
define their sludges as listed hazardous
waste at the point of generation and
manage them accordingly.
  The Agency also is restricting the
placement of EDC/VCM wastewater
treatment sludges on the ground prior to.

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                 Federal Register/Vol.  64,  No. 164/Wednesday, August 25, 19991 Proposed Rules
                                                                       46509
  their being disposed in a landfill (e.g.,
  storage in waste piles, spills). EPA
  wants to ensure that these wastes,
  which are clearly capable of presenting
  unacceptable risk if improperly
  managed, are managed only in the
  manner found to be protective of human
  health and the environment.
    Generators, and other parties involved
  in the management of EDC/VCM
  wastewater treatment sludges, claiming
  that their wastes fall outside the scope
  of the hazardous waste listing must be
  able to demonstrate that sludges
  excluded from the listing description
  are being managed in accordance with
  all of the conditions for being excluded
  from the listing. This means that parties
  claiming the waste falls outside the
  scope of subtitle C must be able to
  demonstrate that (1)  previously
  generated and managed waste (which is
  being claimed as not meeting the K174
  listing) was disposed of in a  landfill;
  and (2) waste currently being managed
  is not being stored, or otherwise
  managed, on the land (e.g., landfarms,
  waste piles) as well as demonstrate that
  the waste will be disposed of in a
  landfill (e.g., have a contract in place
  with a landfill owner/operator that
  specifies intent to manage EDC/VCM
  sludges at the landfill facility). To
  further clarify how today's proposed
  approach would be implemented, below
  we describe these two distinct situations
  where a listing determination will be
  made under this proposed approach.
 i. EDC/VCM Sludges Sent Off-Site
   Under the proposed contingent
 management listing for K174, EDC/VCM
 sludges that already have been shipped
 from the generator facility to a subtitle
 C or subtitle D landfill were never a
 listed hazardous waste. In this instance,
 should a question arise as to the status
 of sludges previous shipped off-site, the
 implementing agency would look to
 indications such as contracts between
 the generator and the landfill owner/
 operator, invoices showing waste was
 delivered to a specific landfill, and
 other documents that clearly show the
 waste was transferred to a subtitle C or
 subtitle D landfill.

 ii. EDC/VCM Sludges at Generator Site
  In this situation, determining whether
 or not an EDC/VCM sludge meets the
 proposed K174 listing would be done in
 a prospective manner, not unlike many
 of the existing regulatory exclusions
 from the definition of solid waste
 (where determinations of whether or not
a material is a waste are often based
upon how the waste will be managed,
i.e., recycled. See, for example,
requirements at 40 CFR 261.2, Table 1,
   and 261.4(b)). Under the existing
   generator requirements in 40 CFR Part
   262, generators of solid w,aste;,must
   determine whether the waste is a listed
   hazardous waste (40 CFR 262.11 (b)).
   Determinations made by generators
   regarding whether their EDC/VCM
   sludges are listed (where these sludges
   have not yet been disposed of off site in
   an appropriate landfill) will be made by
   virtue of where the waste will be sent.
   In situations where the implementing
   agency is questioning any claims by the
  generator of the non-listed status of
  sludges being stored on site, the
  generator should be able to show that
  there is an agreement already in place
  with a transporter and/or landfill
  indicating that these sludges will be
  delivered to a landfill. It is the EPA's
  experience that wastes cannot usually
  be shipped to a commercial landfill
  without first establishing a relationship
  with that landfill, where factors such as
  the amount of waste, the frequency of
  shipments, the physical and chemical
  make up of the waste, etc., are agreed
  upon before the waste ever arrives at the
  landfill.
    In the case of generators who manage
  EDC/VCM in on-site landfills, the
  Agency requests comment on the types
  of records or documentation that  may be
  used to verify or document that the
  waste is managed in the on-site landfill
  and not managed in a land treatment
  unit.
   The Agency notes that it is not our
  intent to condition the regulatory status
  of the waste upon a recordkeeping or
  paperwork requirement. The Agency
 believes that the ability to demonstrate
 the commitment to dispose of the waste
 in a landfill is necessary to ensure the
 waste falls outside the scope of the
 listing. We do not believe that any
 specific recordkeeping requirement
 (e.g., the completion and retention of a
 specific form) is necessary to make this
 demonstration. We believe that
 documentation of previous landfilling of
 the waste and a demonstration of a
 commitment to dispose of currently
 generated waste in a landfill may be
 made by several means. EPA is
 requesting comment on the types of
 records and/or documentation normally
 kept by generators and/or disposal
 facility owner/operators that may be
 used to make such demonstrations (see
 section III.E.2.f, below).
   EDC/VCM wastewater treatment
 sludges that are not listed hazardous
 waste due to contingent management
 will be considered nonhazardous from
 their point of generation. As a result,
such sludges will not be subject to
RCRA subtitle C management
requirements for generation, transport.
   or disposal (including the land disposal
   restrictions), if the waste is destined for
   disposal in a landfill (and the generator
   can demonstrate such intention).
     Of course, if the waste is not disposed
   of in such a unit, then the exemption
   would no longer apply and the waste
   would have to be managed in
   compliance with subtitle C management
   requirements, from the point of
   generation. In other words, if the
   Agency finds that the waste is disposed
   of in a unit other than a subtitle C or D
   landfill, the Agency may cite the
  generator of the waste as being out of
  compliance with all applicable subtitle
  C management requirements. The
  Agency also points out that should EDC/
  VCM wastewater treatment sludges meet
  the listing description for another
  hazardous waste listing, or if the
  wastewater treatment sludges exhibit
  one or more of the characteristics of
  hazardous waste, the sludges must be
  managed as hazardous wastes and are
  not exempt from regulation under
  today's listing determination, regardless
  of how the sludges are managed.
  e. What Specific Comments Is EPA
  Requesting on Implementation of the
  Contingent Management Listing
  Approach?
   The Agency requests comments on
  this proposed contingent management
  listing approach, and may make changes
  to the implementation approach based
  on comments received. EPA notes that
  this contingent management approach
  necessitates that the Agency have the
  ability to confirm whether or not wastes
  claimed to fall outside the scope of the
 listing description are disposed of in a
 landfill as required by the proposed
 listing determination. As a result, some
 type of documentation or demonstration
 that the waste actually is disposed of in
 a landfill (or will be disposed of this
 way) is appropriate.
   EPA is proposing that generators be
 able to provide documentation that
 waste previously generated (for which
 the claim is made that the waste is not
 K174) was disposed in an on-site
 landfill or transported to and received
 by an off-site landfill. In addition, a
 generator must be able to demonstrate
 that waste currently present at the
 generator's facility will be disposed in
 an on-site or off-site landfill, and that
 the waste will not be stored, or
 otherwise managed, on the land prior to
 disposal in a landfill. Appropriate types
 of documentation that may fulfill these
requirements may include: contracts
between a generator and a landfill
owner/operator, invoices documenting
that the waste was transported to and
received by a landfill facility, bills of

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 lading or other shipping papers that
 clearly indicate the type and quantity of
 waste shipped off-site, the date of
 shipment, the name and address of the
 landfill receiving the waste, and the
 date the waste was received by the
 landfill.
   EPA requests comment on the type of
 records, documentation, and
 demonstrations that may be adequate for
 determining compliance with the
 contingent management listing. EPA
 requests comment on what type of
 internal records may be kept by solid
 waste generators that may demonstrate
 intended management of the waste and
 Whether such records are adequate for
 demonstrating compliance with the
 contingent management conditions for
 exclusion from the hazardous waste
 listing. EPA also requests comment on
 its proposal that waste that does not
 meet the terms of the conditional listing
 is hazardous from the point of
 generation.
 3. VCM-A Wastewater Treatment
 Sludges
 a. Is EPA Proposing To Regulate VCM-
 A Wastewater Treatment Sludges?
   Yes, EPA is proposing to list as
 hazardous wastewater treatment sludge
 from the production of vinyl chloride
 monomer using mercuric chloride
 catalyst in an acetylene-based process
 (VCM-A). The sludge is generated at
 one facility as a result of treating water
 running off an area where spent
 mercury catalysts are removed from the
 VCM-A production process. The
 Agency has concluded that the waste
 meets the listing criteria in 40 CFR
 261.11 (a) (3) and is capable of posing a
 Substantial present or potential hazard
 to human health and the environment if
 i[ii|smanaged. For reasons explained in
 more detail below, EPA is proposing
 two alternative approaches for listing
 this waste as hazardous. The Agency is
 requesting comment on both proposed
 approaches.
 b, What Information Led EPA To
 Propose To List as Hazardous VCM-A
 Wastewater Treatment Sludges?
 i. Background
  As previously described in today's
 proposed rule, the manufacture of vinyl
 chloride monomer in an acetylene-based
 process using mercuric chloride
 catalysts generates non-process
 wastewaters as a result of precipitation
 runoff in the production area, as well as
 from using water to  remove spent
catalyst from the reactors. Because of its
 high mercuric chloride content, this
wastewater is collected and treated in a
dedicated non-biological treatment
                        system that uses sodium sulfide to
                        convert the mercuric chloride to
                        mercuric sulfide, which precipitates as
                        a sludge and is dewatered to form a
                        filter cake. This treatment system is
                        operated in a batch-process fashion, and
                        treated effluent is discharged under the
                        facility's NPDES permit. EPA knows of
                        only one facility in the United States
                        that operates an acetylene-based VCM
                        production process. According to the
                        facility's response to the RCRA Section
                        3007 survey, this waste was sent to a
                        permitted hazardous waste landfill for
                        disposal in 1996. Other information
                        provided by the facility in response to
                        a separate RCRA Section 3007 request
                        from EPA indicates this waste was sent
                        to the same permitted hazardous waste
                        landfill from 1990 to 1994 as well. The
                        facility generates approximately 120
                        metric tons of VCM-A wastewater
                        treatment sludge per year.

                        ii. Analytical Results
                         EPA analyzed one sample of this
                        sludge in 1996 in support of this listing
                        determination. The analytical results
                        showed the sludge contained 9,200 mg/
                        kg total mercury, and 0.26 mg/L  in
                        leachate using TCLP. The results for a
                        split sample analyzed by the facility
                        were 17,700 ppm total mercury, and the
                        TCLP result was 0.654 mg/L. These
                        results indicate a very high total
                        mercury concentration (approximately
                        one to two percent of the waste is
                        mercury), and the TCLP results exceed
                        the regulatory level for the mercury
                        toxicity characteristic of 0.2 mg/L. Data
                        generated by EPA in support of a
                        treatability study on this particular
                        waste showed a total mercury
                        concentration (in aliquots of a single
                        sample) ranging from approximately
                        3,000 to 9,000 mg/kg, and TCLP results
                        were all below the regulatory limit.35
                        Other data available to EPA from the
                        facility indicate that approximately 20
                        percent of the tested samples exceed the
                        regulatory level for mercury36.

                        iii. Assessment of Potential Risk
                         EPA's quantitative analysis of the
                       potential groundwater risks posed by
                       this waste assumes waste disposal in an
                       unlined landfill. The Agency is making
                         35 Paul Bishop, Renee A. Rauche. Linda A. Rieser,
                       Markram T. Suidan, and Jain Zhang; "Stabilization
                       and Testing of Mercury Containing Wastes," Draft.
                       Department of Civil and Environmental
                       Engineering. University of Cincinnati. March 31,
                       1999. Please note that this is a draft EPA document
                       not yet peer reviewed. Also, data within the report
                       is still undergoing QA/QC review, and the text,
                       data, and conclusions in the report may change
                       before the document is finalized.
                         36 Summary of Mercury TCLP Data on VCM-A
                       Sludge from Borden Chemicals and Plastics. EPA
                       July 1999.
 use of previously conducted
 groundwater modeling and risk analyses
 for the proposed Hazardous Waste
 Identification Rule (60 FR 66344,
 December 21, 1995) that resulted in an
 estimated dilution and attenuation
 factor (DAF) for mercury of 40. Using
 this DAF and the mercury leachate
 concentration of the VCM-A sludge
 analyzed by EPA (0.26 mg/L), the
 expected concentration of mercury at a
 modeled receptor well (after a release to
 groundwater from an unlined landfill)
 exceeds the maximum contaminant
 level (MCL) for mercury (0.002 mg/L) by
 a factor of three. Using the mercury
 leachate concentration from the
 facility's split sample  (0.654 mg/L), the
 mercury MCL would be exceeded at a
 modeled receptor well by a  factor of
 eight.
   EPA is unable to quantitatively assess
 the potential risk this waste poses when
 disposed in a subtitle C landfill without
 prior treatment. However, we
 qualitatively considered the risk
 associated with such a management
 scenario. There is considerable
 uncertainty about the performance of
 engineered landfills. In the near term,
 especially at regulated subtitle C
 landfills, there are quality assurance
 controls to reduce the  likelihood of
 significant material, installation, or
 facility operation errors that could
 degrade performance of the engineered
 systems. In addition, such landfills have
 ground water monitoring and leachate
 management controls to further reduce
 the chances of significant ground water
 risk. However, in the long-term, there is
 considerable uncertainty as to how well
 engineered  systems will operate and
 whether there will continue to be long-
 term care and maintenance after the
 regulatory post-closure period ends.
 EPA can only qualitatively consider the
 potential long-term risk of wastes in
 subtitle C landfills. However, we
 considered the above mentioned
 uncertainties, along with the
 quantitative estimates of potential risk
 in unlined landfills, when assessing the
 potential risks of managing untreated
 wastes in a subtitle C landfill, such as
 VCM-A sludges that contain persistent
 constituents such as mercury.

 iv. Rationale for Proposed Hazardous
 Waste Listing Determination
  EPA is proposing two rationales to
 "list" this waste as hazardous, both of
 which lead the Agency to conclude we
 should propose to list this wastestream
 as hazardous waste. First, EPA believes
 it is plausible that this waste may be
mismanaged and disposed of in an
unlined and uncovered landfill and that
it is capable of posing a substantial

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                 Federal Register /Vol. 64. No.  164/Wednesday, August 25,  1999/Proposed Rules
                                                                        46531
  hazard if so managed. Second, based
  upon information EPA has, including
  information on liner performance and
  the mobility of mercury under certain
  pH conditions, EPA believes that even
  when disposed of in a landfill that is
  compliant with Subtitle C landfill
  standards, this waste is likely to leach
  significant quantities and
  concentrations of mercury that long-
  term degradation of the landfill's
  leachate control systems (especially
  after post-closure care has ended) would
  plausibly cause an unacceptable release
  of mercury into groundwater and has
  the potential to pose a substantial
  hazard when this waste is so managed
  without improved prior treatment. EPA
  requests comment on the basis for the
  rationales described above, both for the
  disposal scenario in an unlined landfill,
  and the disposal scenario in a landfill
  compliant with subtitle C landfill
  standards.
    The Agency's analysis of potential
  risk indicates that disposal of the VCM-
  A sludge in an unlined landfill may
  result in risks due to the migration of
  mercury in groundwater to a receptor
  well in concentrations that exceed the
  MCL for this constituent. The Agency
  notes that the single facility generating
  this waste reports managing the waste
  by disposing of it in a subtitle C landfill
  for certain years. Therefore, a simple
  conclusion may be to dismiss the
 potential risk for the groundwater
 pathway (assuming it continues to go to
 a subtitle C landfill) due to the presence
 of a landfill liner and leachate
 collection. In addition, (as mentioned
 previously) the mercury in the waste is
 in the form of mercuric sulfide, which
 generally is found to be a relatively
 insoluble form of mercury (indicated by
 only a relatively small percentage of the
 total mercury content of the waste
 leaching under the TCLP). However,
 data recently collected by the Agency
 and preliminary results from the
 analysis of this waste indicate that this
 waste may not behave in the same
 manner (in terms of the mobility of
 mercury in sulfidic form) in all
 environments. As discussed briefly
 below (and further in the Land Disposal
 Restrictions, Section V.F.), available
 data indicate that although the mercury
 in the VCM-A sludge remains relatively
 immobile at pH levels of 6 or lower,
 higher pH conditions will result in
 mercury mobilizing to the aqueous
 phase.37
    Using data from a collected sample of
  the VCM-A wastewater treatment
  sludge,; constant pH leaching -tests were
  conducted on the waste sample to
  determine the effect pH has on the
  stability of the waste. The preliminary
  results of the constant pH leaching tests
  showed that mercury leachate
  concentrations were lower in samples
  leached at a pH of 6.0 or lower (e.g.,
  0.00582 mg/L at pH=6 after 24 hours),
  compared with concentrations at higher
  pH conditions. The same sample
  leached at pH of 10 produced a
  significantly higher mercury leachate
  concentration of 1.63 mg/L after 24
  hours.38
    Information obtained by EPA on the
  pH levels of actual leachate collected
  from the landfill cell in which the
  VCM-A wastewater treatment sludge
  currently is disposed show that the pH
  is greater than 9.39 If this pH value is
  indeed indicative of the disposal
  environment for this waste, then based
  upon the pH relationship identified in
  the preliminary results of constant pH
  leach tests described above, one would
  predict that the mercury would be
  significantly mobilized under the
  disposal environment actually being
  used for this waste.
   In summary, although the waste is
  disposed in a subtitle C landfill, the fact
  that the mercury in the waste may
  mobilize at pH levels greater than 6
  means that the leach test results may
  under predict concentrations in
  leachate. In case of significant leachate
  contamination, the landfill liner may be
 the only guard against the release of
 mercury to the environment (due to the
 fact that the waste is not stable in this
 landfill disposal scenario). Should the
 liner fail, mercury present in the
 leachate would be released to the
 environment.
  EPA acknowledges that a liner/
 leachate collection system in a subtitle
 C unit serves to contain and remove
 waste leachate and provides important
 environmental protection. However,
 EPA recognizes that there is inherent
 uncertainty in such systems, and it
 believes that the purpose of the RCRA
 hazardous waste treatment requirements
 (as expressed by Congress) is to reduce
 the uncertainty inherent in engineered
 containment approaches. EPA believes
 that waste containment systems will
 tend to degrade with time. Eventually,
 synthetic liners will degrade and
 leachate collection systems will cease
 operation. As put forth in the proposed
  37 H. Lawrence Clever. Susan A. Johnson, and M.
elizabeth Derrick, The Solubility of Mercury and
Some Sparingly Soluble Mercury Salts in Water and
Aqueous Electrolyte Solutions. J. Phys. Chem. Ref.
Data. Vol. 14, No. 3. 1985. page 652.
  38 Paul Bishop, op. tit., p. 14.
  39 E-mail communication to John Austin, U.S.
EPA, from Mitch Hahn, Waste Management
Corporation, April 14, 1999.
   Liner and Leak Detection Rule (52 FR
   20218,-May 29. 1987), no liner can be
   expected to remain impervious forever.
   Properly installed double liner and
   leachate collection systems, together
   with final covers placed at closure, will
   substantially reduce" releases during the
   operating life and post-closure care
   period. However, these technologies
   may not always reduce the longer-term
   risk for landfills to acceptable levels for
   persistent, mobile, and highly toxic
   compounds. This is because the
  containment system may not prevent
  leachate release from the landfill
  indefinitely, for example after the post-
  closure period, when active
  maintenance of the cap and leachate
  collection system may be reduced or
  may end. The Agency has found that
  treatment of the waste under the LDR
  standards of RCRA subtitle C will
  significantly reduce potential risks from
  the disposal of this waste over the long
  term. This is particularly important for
  a constituent such as mercury, that is
  persistent and does not degrade.
  Treatment in accordance with
  prescribed BOAT can reduce the
  possibility that leachable mercury is
  available for release to the environment.
  Again, a liner/leachate collection system
  in a subtitle C unit is expected to
  contain waste leachate and lessen the
  risk while such a system is intact.
  However, even assuming a low
  probability of failure, because the TCLP
  may be significantly under predicting
  leachability for this waste in this
 subtitle C disposal scenario, there may
 still be a release of mercury that results
 in an exceedance of the MCL. While
 there are uncertainties in this
 assessment, it still  illustrates that the
 mercury concentrations in the receptor
 well may be close to, and could even be
 higher than the MCL. Given the well-
 documented toxicity and persistence of
 mercury, the potential for greater
 mobility of mercury from this particular
 waste in a subtitle C landfill (than
 predicted by the TCLP), and the
 uncertainties associated with
 engineered landfills over the long-
 term—as reflected in statutory language
 regarding treatment requirements—EPA
 believes that the disposal of this waste,
 untreated, in a subtitle C landfill may
 not be protective and therefore may
 warrant listing the waste as hazardous.
   In EPA's view, it may violate
 Congressional intent to allow a waste
 that the Agency otherwise would list as
 hazardous (absent the fact that the waste
 is managed untreated in a Subtitle C
 landfill) to be disposed in a hazardous
waste landfill under conditions that
may result in the hazardous constituents

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Federal Register/Vol.  64,  No. 164/Wednesday, August 25,  1999/Proposed Rules
 in the waste leaching from the waste
 (due to the high pH of the landfill
 Environment). Congress clearly
 expressed its intent that the Agency is
 not to place excessive reliance or
 confidence in landfill design and liners
 for problematic wastes. In the
 Hazardous and Solid Waste
 Amendments (HSWA) of 1984. Congress
 explicitly added as one of the
 "findings" to RCRA that "land disposal
 facilities are not capable of assuring
 Ipng-term containment of certain
 hazardous wastes" and that "reliance on
 land disposal should be minimized or
 eliminated."40 As a result of this
 finding, and others,  Congress added the
 land disposal restriction program to
 RCRA, which significantly restricts land
 disposal of hazardous wastes and
 provided in section 3004 (m) the
 mandate that EPA develop treatment
 standards for "diminishing the toxicity
 Of wastes or substantially reducing the
 likelihood of migration of hazardous
 constituents from the waste so that
 short-term and long-term threats to
 human health and the environment are
 minimized." In addition, the legislative
 history to RCRA section 3004(m) states
 that this section "makes Congressional
 intent clear that land disposal without
 prior treatment of these wastes with
 significant concentrations of highly
 persistent, bioaccumulative constituents
 is not protective of human health and
 the environment." (130 Cong. Rec. S
 9178; daily ed. July 25, 1984). Were we
 to propose a no list determination for
 this waste based solely upon the fact
 that this waste currently is disposed in
 a subtitle C landfill—ignoring the high
 levels of total mercury in the waste, its
 potential for leaching (at high pH), and
 the likely benefits of treatment—we
 would be bypassing Congressional
 intent that wastes be treated to reduce
 toxicity and/or migration of hazardous
 constituents before final disposal.
  EPA views the statute and legislative
 history as sufficient justification to
 evaluate in a listing determination all
 risks of land disposal, including in
 appropriate cases problems that might
 be associated with voluntary disposal of
 untreated wastes in permitted subtitle C
 facilities. This is particularly true where
risks presented by a waste will be high
 if releases occur, if the waste is highly
persistent, and treatment of the waste
under subtitle C would significantly
reduce these risks.  In the case of the
VCM-A wastewater treatment sludges,
the potential risks presented by the high
content of mercury in the waste if a
release should occur, warrants the
imposition of treatment standards in
 •WRCRA section 1002{b)(7). 42 U.S.C. 6902(b)(7).
                        accordance with Congress's intent.
                        Although the generator currently sends
                        VCM-A wastewater treatment sludges to
                        a lined subtitle C landfill facility, we
                        believe that substantial risks are
                        plausible, given the possibility of
                        eventual landfill degradation or failure.
                        The estimated risks due to migration
                        from an unlined landfill provide an
                        indication of the potential risks that will
                        occur if mercury is released from the
                        lined landfill due to failure of the unit
                        to contain the waste leachate over time.
                          Absent a hazardous waste listing, the
                        Agency has no mechanism for requiring
                        that the waste be treated prior to
                        disposal to ensure that the mercury in
                        the waste does not leach from the waste
                        to the surrounding environment (and
                        hence provide some protection of
                        human health and the environment in
                        the event of a liner failure).
                        Furthermore, the Agency has little
                        assurance that the waste will continue
                        to be managed in a subtitle C landfill.
                          Listing a waste as hazardous provides
                        a level of certainty with regard to the
                        management and stewardship of a waste
                        as well. Given the quantity of mercury
                        contained in the VCM-A wastewater
                        treatment sludge and the potential
                        solubility of this large quantity of
                        mercury, the Agency tentatively
                        concludes that it is appropriate that the
                        waste be managed in accordance with
                        the "cradle-to-grave" management
                        system established under RCRA Subtitle
                        C. By listing this waste as hazardous,
                        EPA and the general public are afforded
                        a greater level of certainty with respect
                        to the manner in which the waste must
                        be managed. It will have to be
                        accumulated and stored in closed
                        containers, sent off-site for treatment
                        and disposal within a relatively short
                       time of the time it was generated,
                       transported by a registered hazardous
                       waste transporter and accompanied by a
                       manifest, and treated and disposed at
                       facilities permitted to handle hazardous
                       wastes.
                         The Agency bases its listing
                       determinations on an evaluation of risks
                       from plausible management practices.
                       For the reasons just described, EPA
                       believes that disposal of untreated
                       VCM-A sludge in a subtitle C landfill
                       represents one plausible management
                       scenario and that this scenario could
                       lead to significant problems. Equally
                       important, the Agency questions
                       whether the current waste management
                       practices are the only practices that will
                       be employed by the facility in the
                       future. That is, the Agency believes
                       other management practices are
                       plausible. First, information available to
                       the Agency documents only that the
                       facility has sent VCM-A wastewa'ter
  treatment sludges to a subtitle C landfill
  for disposal for some periods after 1990.
  Specifically, information provided by
  the facility in response to a specific
  RCRA Section 3007 request from EPA
  indicates this waste was sent to a
  subtitle C landfill from 1990 to 1994;
  and according to the facility's response
  to the RCRA Section 3007 survey, this
  waste was sent to a permitted hazardous
  waste landfill for disposal in 1996. In
  addition, we have no information with
  regard to the disposal of the waste prior
  to 1990. The Agency does know that the
  facility had as many as 800 drums of the
  mercuric sulfide sludge stored on site in
  1985; however the Agency has no
  information with regard to the ultimate
  management of the waste.41 Given the
 fact that the Agency does not have a
 complete record of how the VCM-A
 sludge was managed in the past, the
 Agency believes that it is reasonable to
 assume that the VCM-A sludge may be
 managed in an non-subtitle C landfill in
 the future.
   Therefore, for the purposes of
 assessing potential risk, the Agency
 believes a plausible mismanagement
 scenario'can also include an unlined
 landfill, the scenario in which the
 Agency's risk analysis indicates a
 potential for the concentration of
 mercury at a modeled receptor well to
 be as much as eight times higher than
 the MCL for mercury (based upon the
 TCLP results and a DAF of 40).
   Our assessment includes predicted
 exceedances of the MCL (based upon
 the record sample EPA collected)
 assuming disposal in an unlined
 landfill; and a qualitative consideration
 of the possible risks when disposed in
 a subtitle C landfill without better
 treatment. Although  risk analyses
 provide one of the principal bases for a
 listing determination, estimates of risk
 levels do not represent the sole basis for
 a listing determination. Other factors
 generally are considered in making a
 listing decision. In fact, the Agency's
 listing decision policy uses a "weight-
 of-evidence" approach in which
 calculated risk information is a single
 key factor. Available risk values are
 assessed with all other data available to
 determine whether a waste is or is not
 a hazardous waste (see the discussion of
 EPA's hazardous waste listing
 determination policy in the proposed
 listing for wastes generated by the dye
 and pigment industries at 59 FR 66073,
 December 22, 1994). In our decision to
 propose to list this sludge as hazardous,
  41 "Reclassification Petition" submitted to
Louisiana Department of Environmental Quality,
Hazardous Waste Division, by Borden Chemical,
September. 1987, p. III-2.

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                 Federal Register/Vol.  64,  No. 164 /Wednesday,  August 25, 1999 /Proposed Rules
                                                                         46513
  the Agency considered several factors,
  including the extensive documentation
  on the toxicity of mercury, as well as the
  other criteria listed in 261.11 (a) (3) to
  arrive at a listing determination,  as
  further summarized below.
    Mercury has been identified by
  several different governmental agencies,
  including EPA, the Agency for Toxic
  Substances and Disease Registry
  (ATSDR), the Food and Drug
  Administration (FDA), and the
  Occupational Safety and Health
  Administration (OSHA), as a significant
  human toxicant. Each of these Agency's
  has developed regulations, guidelines,
  and/or standards to protect people from
  the serious potential health effects of
  exposure to mercury. In addition, it also
  is well documented that mercury is
  persistent in the environment, does not
  degrade, and bioaccumulates in
  wildlife, particularly fish. Agency
  studies, including the recently
  published Mercury Study Report  to
  Congress42 have documented the
  neurotoxicity of mercury and the
  potential adverse human health and
  environmental effects that may result
  from the release of mercury to the
  environment. In addition, ATSDR has
  published a toxicological profile for
  mercury which examines, summarizes
  and interprets toxicological information
 and epidemiological evaluations on
 mercury.43 Research conducted by both
 EPA and ATSDR provides
 documentation of the highly toxic
 effects of human exposure to mercury.
 Human consumption of highly-
 contaminated food can produce overt
 mercury neurotoxicity. Neurotoxic
 effects from mercury contamination
 range from subtle decrements in motor
 skills and sensory ability at
 comparatively low doses to tremors,
 inability to walk, convulsions and death
 at extremely high exposures. Human
 consumption offish or grain
 contaminated with high levels of
 mercury can result in permanent
 damage to the brain, kidneys and
 developing fetuses. Adverse effects of
 mercury on fish include death, reduced
 reproductive success, impaired growth
 and development and behavioral
 abnormalities. Exposure to mercury also
 can cause adverse effects in plants, birds
 and mammals. The extent and
 availability of toxicity assessments for
 mercury is relatively extensive (see
 EPA's "Mercury Study Report to
 Congress" and/or EPA's "Action Plan
   for Mercury")aA. Certainty with regard
   to the potential risks to human health
   and the environment from exposure to
   mercury is well documented. Mercury
   presents significant human health
   threats when released to the
   environment.
    Wastewater treatment sludges from
   the VCM-A process using mercuric
   chloride catalyst contain significant
   levels of total mercury. As mentioned
   previously, approximately 120 metric
   tons of the sludge, containing about one
  percent (or 1 MT) of mercury, is
  generated per year at a single facility.
  One metric ton of mercury is
  approximately 20 times as much
  mercury as is received typically by a
  single municipal solid waste landfill
  from all sources in one year. EPA also
  notes that in this particular case, we
  believe the mercury is likely to be
  significantly leachable at pH levels of a
  typical hazardous waste landfill. The
  Agency considers this quantity of
  potentially leachable mercury generated
  from a-single facility and disposed of
  off-site to be significant. As outlined in
  the Draft EPA Action Plan for
  Mercury45, and EPA's Waste
  Minimization National Plan41*, it is
  important to the protection of human
  health and the environment that all
  anthropogenic sources of mercury
  emissions to the environment be
  minimized. Given the inherent risks
  associated with mercury, EPA believes
  it is necessary to ensure, to the greatest
 extent possible, that wastes containing
 significant quantities of mercury are
 safely managed and to guard against
 potential mismanagement.
   Upon consideration of the factors
 enumerated in 40 CFR 261.11 (a) (3)  and
 those summarized in the 1994 Dyes and
 Pigments Proposed Rule for making a
 hazardous waste listing determination,
 EPA made the following conclusions
 with respect to this waste. In terms of
 waste characterization, data available on
 this waste indicate with relative
 consistency that the waste contains a
 significant amount of total mercury,
 regardless of variation in pH and
 leachable mercury. Furthermore, in this
 particular case, we believe that the
  42 U.S. Environmental Protection Agency (1997),
EPA-452-R-97-003-009.
  43 "Toxicological Profile for Mercury," ATSDR,
April. 1999; http://www.atsdr.cdc.gov/press/
ma990419.html.
  44 "Mercury Study Report to Congress." volumes
I-VIII, EPA-452/R-97-003, December 1997: and
EPA Action Plan for Mercury (Atttachment 1 to "An
Agency-Wide Multi-media Strategy for Priority PBT
Pollutants"), http://www.epa.gov/ttnuatwl/
112nmerc/mercury.html.
  45 Attachment to A Multimedia Strategy for
Priority Persistent, Bioaccumulative, and Toxic
(PBT) Pollutants, November 16, 1998, EPA 742/
D98/001, http://www.epa.gov/opptintr/pbt/
pbtstrat.htm.
  46 Waste Minimization National Plan. US EPA
1994, EPA530-R-94-045, http://www.epa.gov/ •
rgytgrnj/specinit/p2/volprog/wm.htm.
   mercury is likely to be more leachable
   than the TCLP test indicates. It is well
   documented that mercury is a human
   toxicant. Mercury is persistent in the
   environment, does not degrade, and
   bioaccumulates in wildlife, particularly
   fish. These conclusions correspond to
   the listing factors at 40 CFR Sections
   261.11 (a) (3) (i), (iv), (v), and  (vi),
   respectively.
    After considering the listing factors in
   261.11 (a) (3), and in particular the
   factors at 261.11 (a)(3) (i)-(vi) (which
  include potential risks to groundwater
  from unregulated disposal of this waste,
  the  fact that mercury is a human
  toxicant,  is persistent in the
  environment, does not degrade,
  bioaccumulates in wildlife, and is
  present in very high concentrations in
  this waste), as well as several of the
  "additional factors" listed in the 1994
  Proposed Rule for Wastes Generated by
  the Dyes and Pigments Industry, and
  taking into account the Agency's overall
  goals to reduce releases of mercury to
  the environment, EPA is proposing to
  list this waste as hazardous. The
  proposed listing description is shown
  below.
  K175 Wastewater treatment sludges from
     the production of vinyl chloride
     monomer using mercuric chloride
     catalyst in an acetylene-based process.
   The proposed listing of VCM-A
 wastewater treatment sludges, which
 contain substantial amounts of total
 mercury is, in effect, an extension of the
 Agency's policy with regard to mercury
 emissions. The Agency believes that
 listing these wastewater treatment
 sludges as hazardous will provide
 incentive for the facility to find ways to
 reduce the overall quantity of mercury-
 containing VCM-A sludges generated.
 EPA believes there may be opportunities
 for this type  of reduction through
 improved catalyst handling practices.
 Improved handling practices may result
 in a reduction in the amount mercuric
 chloride released in and around the
 VCM-A process area where it becomes
 available for introduction to the
 wastewater treatment system. In turn,
 this reduction would result in an overall
 decrease in the amount  of mercury
 available for potential release to the
 environment.
   Once a waste is listed as a hazardous
 waste, the waste is prohibited from land
 disposal unless it is treated in
 compliance with treatment standards
 established under the RCRA land
 disposal restrictions standards program.
The mercuric sulfide sludge generated
from the VCM-A production process is
unique in that this waste contains a very
high amount of total mercury, and the

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Federal Register/Vol.  64,  No.  164/Wednesday, August 25,  1999/Proposed Rules
 mercury Is present in the waste in a
 relatively insoluble form as measured
 Using the TCLP. However, the
 preliminary findings of the EPA/ORD
 study described above suggest that
 variability in the pH of the waste as
 generated, and higher pH conditions
 potentially encountered in the disposal
 unit where this waste is managed, can
 affect the stability of the VCM-A sludge
 when disposed in a subtitle C landfill.
 The Agency, therefore, is proposing
 specific LDR treatment standards for
 this waste to minimize the potential
 release of mercury to die environment
 from this waste. A discussion of the
 proposed BDAT treatment standards for
 newly listed VCM-A wastes is provided
 later  in this notice.
 c. What Alternative Is EPA Considering
 for a  Proposed Listing Determination?
 i. Summary of Alternative Listing
 Option
  The alternative listing option EPA is
 proposing today is to list the VCM-A
 wastewater treatment sludges as
 hazardous waste, unless the waste is
 disposed in a subtitle C landfill. In
 addition, under this alternative option,
 VCM-A wastewater treatment sludges
 that exhibit the toxicity characteristic
 for mercury will be listed as hazardous.
 In other words, this waste will not meet
 the proposed K175 listing description,
 and therefore will not be listed
 hazardous waste from the point of
 generation, so long as it is disposed in
 a subtitle C landfill, and it does not
 exhibit the TC for mercury.
 it. Rationale for Alternative Listing
 Option
  As  described earlier, EPA believes
 that the VCM-A sludge meets the
 criteria for being listed as a hazardous
 waste, principally due to the high
 concentration of mercury, a highly toxic
 constituent, in this waste. Available
 information indicates that the direct
 disposal of untreated VCM-A sludge in
 a subtitle C landfill may result in a
 marked increase in the mobility of
 mercury, and that, should the liner
 system ultimately degrade, this mercury
 can be released to groundwater and
 potentially reach a receptor well in
 concentrations at the MCL. Also, the
 Agency believes that disposal of these
 wastes in an unlined landfill is a
 plausible mismanagement scenario,
 which would result in exceedances of
 the MCL by up to a factor of eight. The
 Agency is seeking comment on these
 tentative conclusions and diis proposed
 listing determination. Should the
Agency receive data or other
information on the conclusions drawn
                        by the Agency with regard to the
                        management of the waste and the
                        behavior of this waste in the
                        environment, particularly with regard to
                        the potential for the mercury in the
                        waste to leach under conditions of high
                        pH levels, the Agency will consider
                        alternative approaches. For example, if
                        direct disposal of untreated VCM-A
                        sludge in a subtitle C landfill can be
                        shown to be protective without further
                        treatment of this waste, due to the
                        relative  insolubility of mercuric sulfide
                        or expected long-term performance of
                        subtitle  C systems, EPA will consider a
                        conditional listing of VCM-A. Such an
                        conditional listing would specify that
                        the wastewater treatment sludges are
                        listed only if the waste is not disposed
                        in a subtitle C landfill, or put another
                        way, the sludges would not be listed
                        hazardous waste from the point of
                        generation  if they are disposed in a
                        subtitle  C landfill.
                          As mentioned above, this alternative
                        regulatory approach is based upon  the
                        presumption  that  disposal of untreated
                        VCM-A sludge in a subtitle C landfill is
                        protective.  However, the Agency also is
                        concerned that this waste can
                        sometimes fail the TC for mercury (as
                        discussed earlier,  approximately 20
                        percent of the time based upon EPA and
                        facility data). The existing treatment
                        standards that otherwise would apply to
                        this waste if it was characteristically
                        hazardous for mercury include
                        incineration (Le., D009 high mercury/
                        organic subcategory requires either
                        incineration or mercury recovery),
                        which may not be the most
                        environmentally-sound manner in
                        which to treat the  waste prior to
                        disposal. This is discussed in more
                        detail in the LDR portion of today's rule
                        (Section V). Because of this concern,
                        this alternative option is structured in a
                        fashion that allows the treatment
                        standards being proposed today for
                        K175 to apply in lieu of the existing
                        standards for D009 for those VCM-A
                        wastes that  exhibit the characteristic for
                        mercury.
                         EPA requests comment on this
                        proposed alternative listing approach.
                        Also, EPA requests comment on
                        whether  it may be more appropriate to
                        simply list the VCM-A wastewater
                        treatment sludge unless it is sent to a
                        subtitle C landfill,  and propose
                        alternative LDR treatment standards that
                        would apply to VCM-A wastewater
                        treatment sludges that exhibit the TC for
                        mercury. We note that the Agency
                        presently is revisiting the IMERC
                       standard as  part of a comprehensive re-
                        evaluation of the LDR treatment
                       standards for mercury-bearing wastes
                        (see  May'28, 1999 ANPRM; 64 FR
 28958). To the extent time allows, the
 Agency will consider relevant issues
 raised in the ANPRM in developing this
 final listing determination. However,
 because of the different schedules of
 these two actions and the consent
 decree deadline for finalizing today's
 proposed rule, we will not necessarily
 be able to consider any comments
 submitted to the ANPRM in finalizing
 today's rule.
   The Agency's proposed alternative
 listing description for VCM-A
 wastewater treatment sludges that will
 define this waste as hazardous only
 under certain conditions is as follows:
 K175  Wastewater treatment sludges from
    the production of vinyl chloride
    monomer using mercuric chloride
    catalyst in an acetylene-based process,
    unless: i) the sludges are disposed in a
    subtitle C landfill, and ii) the sludges do
    not fail the toxicity  characteristic for
    mercury in 40 CFR  261.24, and iii) the
    generator  maintains documentation
    demonstrating that the waste was
    disposed of in a subtitle C landfill or
    consigned to a transporter or disposal
    facility that provided a written
    commitment to dispose of the waste in
    a subtitle C landfill. Respondents in any
    action brought to enforce the
    requirements of subtitle C must, upon a
    showing by the government that the
    respondent managed wastewater
    treatment  sludges from the production of
    vinyl chloride monomer using mercuric
    chloride catalyst in  an acetylene-based
    process, demonstrate that they meet the
    terms of the exclusion set forth above. In
    doing so, they must provide appropriate
    documentation (e.g., contracts between
    the generator and the landfill owner/
    operator, invoices documenting delivery
    of waste to landfill,  analytical results or
    other information showing the waste
    does not fail the toxicity characteristic
    for mercury, etc.) that the terms of the
    exclusion were met.
  The Agency requests comment on this
alternative listing approach for VCM-A
sludge. As already mentioned, EPA
might choose this alternative regulatory
approach  if it decides direct disposal of
untreated VCM-A sludge is protective
without further treatment of this waste,
due to the relative insolubility of
mercuric sulfide, and  the groundwater
protections a lined landfill does
provide.

d. What Is the Status of Landfill
Leachate From Previously Disposed
Wastes?

  Leachate derived from the treatment,
storage, or disposal of listed hazardous
wastes is classified as  a hazardous waste
by virtue of the "derived-from" rule in
40 CFR 261.3(c)(2). The Agency has
been clear in the past that hazardous
waste listings apply to wastes disposed .

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                Federal Register /Vol. 64. No.  164/Wednesday, August 25,  1999/Proposed Rules
                                                                       46515
  of prior to the effective date of a listing,
  even if the landfill ceases disposal of the
  waste when the waste becomes
  hazardous. See 53 FT? 31147, August 17,
  1988. We also have a well-established
  interpretation that listings likewise
  apply to leachate derived from the
  disposal of listed hazardous wastes,
  including leachate derived from wastes
  disposed before a listing effective date
  which meet the listing description. We
  are not reopening any of these issues
  with this proposed rulemaking.
    Of course, as set out in detail in the
  August 1988 notice, this does not mean
  that landfills holding wastes that are
  listed now as hazardous become subject
  to subtitle C regulation. However,
  previously disposed wastes now
  meeting a listing description, including  ,
  residues such as leachate that are
  derived from such wastes, and that are
  managed actively do become subject to
  subtitle C regulation. See  53 FR 31149,
  August  17, 1988. In many, indeed most
  circumstances, active management of
  leachate would be exempt from subtitle
  C regulation because the usual pattern
  of management is discharge either to
  POTWs via the sewer system, where
  leachate mixes with domestic sewage
  and is excluded from RCRA jurisdiction
  (see RCRA Section 1004(27) and 40 CFR
  261.4(a)(l)), or to navigable waters, also
 excluded from RCRA jurisdiction (see
 RCRA Section 1004(27) and 40 CFR
 261.4(a)(2)). In addition, management of
 leachate in wastewater treatment tanks
 prior to discharge under the CWA is
 exempt from RCRA regulation (40 CFR
 264.1(g)(6)).
   If actively managed, landfill leachate
 and gas condensate derived from the
 newly-listed VCM-A waste proposed for
 listing in today's notice could be
 classified as K175. In  such
 circumstances, we would be concerned
 about the potential disruption in current
 leachate management that could occur,
 and the possibility of redundant
 regulation. Recently, this issue was
 raised to the Agency in the context of
 the petroleum refinery waste listings.
 See 63 FR 42173, August 6, 1998. A
 commenter expressed concern that,
 because some of the commenter's non-
 hazardous waste landfills received
 newly-listing petroleum wastes prior to
 the effective date of the listing decision,
 the leachate that is collected and
 managed from these landfills would be
 classified as hazardous. The commenter
 argued that this could lead to vastly
 increased treatment and disposal costs
without necessarily any environmental
benefit. After examining and seeking
comment on this issue, we  published a
final rule that temporarily defers
regulation of landfill leachate and gas
  condensate derived from certain listed
  petroleum refining wastes (K169-K172)
  that were disposed before, but not after,
  the new lisiings became Iffeclive,
  provided certain conditions are met. See
  64 FR6806, February 11, 1999.
    At the time this issue was brought to
  the Agency's attention in the context of
  the petroleum refinery waste listings,
  EPA's Office of Water had recently
  proposed national effluent limitations
  guidelines and pretreatment standards
  for wastewater discharges—most
  notably, leachate—from certain types of
  landfills. See 63 FR 6426, February 6,
  1998. In support of this proposal, EPA
  conducted a study of the volume and
  chemical composition of wastewaters
  generated by both subtitle C (hazardous
'  waste) and subtitle D (non-hazardous
  waste) landfills, including treatment
  technologies and management practices
  currently in use. EPA proposed effluent
  limitations (for nine pollutants in the
  Non-Hazardous Subcategory) for direct
  dischargers. See 63 FR 6463. Most
  pertinent to finalizing the temporary
  deferral for the petroleum refining
  wastes, EPA did not propose
  pretreatment standards for subtitle D
  landfill wastewaters sent to POTWs
  because the Agency's information
  indicated that such standards were not
 required.
   The conditions included in the
 temporary deferral published on
 February 11, 1999 are that the leachate
 is subject to regulation under the Clean
 Water Act, and the leachate cannot be
 stored in surface impoundments after
 February 13, 2001. See 40 CFR
 261.4(b)(15). We believed that it was
 appropriate to temporarily defer the
 application of the new waste codes to
 such leachate in order to avoid
 disruption of ongoing leachate
 management activities while the Agency
 decides how to integrate the RCRA and
 CWA regulations consistent with RCRA
 Section 1006(b)(l). We believe that the
 same fact pattern fully discussed in the
 February 11, 1999 rulemaking applies in
 this situation as well. As such, we
would be concerned about forcing
pretreatment of leachate even though
pretreatment is neither required by the
CWA, nor needed. Therefore, we are
proposing to temporarily defer the
regulation of landfill leachate and gas
condensate derived from the VCM-A
wastes, with the same conditions as
described in 40 CFR 261.4(b)(15) for
petroleum wastes. We believe the issue
of whether disruptions can be
minimized through integration of CWA
and RCRA rules will be more amenable
to resolution once the CWA rulemaking
is completed.
  e. What Specific Comments Is EPA
  Requesting on the Agency's Proposed
  Listing of VCM-A Wastewater
  Treatment Sludges?
    The Agency requests comments on
  the proposed listing of all VCM-A
  wastewater treatment sludges as well as
  the proposed conditional listing for this
  waste. In addition, the Agency requests
  comment on alternative management
  practices that may either be in use or
  may be appropriate for this.wastestream,
  other than the disposal of these sludges '
  in subtitle C landfills.
    We also request any available
  information on whether or not the
  VCM-A wastes were previously
  disposed in non-hazardous landfills.
  Even if-we do not receive any
  information that previously disposed
  VCM-A wastes will result in generation
  of hazardous landfill leachate and gas
  condensate, we may still choose to
  promulgate the temporary deferral for
  landfill leachate and gas condensate
  from this waste. This is because
  someone may discover this problem
  later (after the effective date of the
  listing), so, by having a temporary
  deferral in place, it would be possible to
  avoid disruption of ongoing leachate
  management activities while we further
  examine this issue and await the CWA
  final rule.
 4. Methyl Chloride Wastewater
 Treatment Sludges
 a. How Is EPA Proposing To Regulate
 Methyl Chloride Wastewater Treatment
 Sludges?
   EPA is proposing not to list as
 hazardous sludges from the treatment of
 wastewaters generated from methyl
 chloride production processes. This
 wastestream does not meet the criteria
 set out at 40 CFR 261.11 (a) (3) for listing
 a waste as hazardous. It does not pose
 a substantial present or potential hazard
 to human health or the environment.
 The Agency identified limited risks to
 consumers of groundwater.
 b. What Information Led EPA To
 Propose Not To List as Hazardous
 Methyl Chloride Wastewater Treatment
 Sludges?
  EPA identified only one facility that
 generates sludges from the treatment of
 wastewaters generated from the
 production of methyl chloride and does
 not currently manage the waste as
 hazardous. The results of the RCRA
 Section 3007 survey for the chlorinated
 aliphatics industry show that this
facility generates less than 800 metric
tons of this sludge each year and
disposes of the sludge in an on-site
landfill along with other wastes from

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Federal Register/Vol.  64,  No. 164/Wednesday,  August 25,  1999/Proposed Rules
 the facility. The landfill is lined and has
 a leachate collection system.
   In conducting the risk assessment for
 this sludge, EPA considered one
 management scenario, disposal in an
 on-site landfill. The Agency analyzed
 potential risks from methyl chloride
 wastewater treatment sludge by
 modeling a non-groundwater pathway.
 The Agency's analysis of potential risks
 due to volatile emissions from the
 landfill resulted in negligible risks to
 individuals in the surrounding area. The
 Agency also conducted a bounding (i.e.,
 worst case) risk analysis to estimate
 potential risks to groundwater
 consumers. This analysis used the
 leachate concentration measured from a
 sample of the facility's methyl chloride
 wastewater treatment sludge, and
 assumed the direct ingestion of this
 leachate by an adult for a period of 58
 years. This bounding analysis resulted
 in a risk of 5E-5 for one constituent,
 arsenic.
  The Agency views the arsenic risk
 results from the bounding analysis as
 marginal. Assuming a landfill DAF of
 only 5 (a reasonable assumption for an
 unlined landfill), the predicted risk
 becomes 1E-5, which is the typical level
 identified by EPA as posing sufficient
 risk to require the waste to be listed as
 hazardous(see 59 FR 66072, 66077).
 However, for this particular facility,
 EPA believes that the actual risk from
 this waste will be much lower than the
 risk level predicted by the bounding
 analysis given that the landfill currently
 used by the single facility generating
 this waste is lined with a 24-inch clay
 liner and has a leachate collection
 system.
  The Agency believes that the
 management practice of most concern
 (on-site landfill) was assessed, given
 that it is the only management practice
 used by the single facility generating the
 waste. Given that the landfill is located
 on site and has significant remaining
 capacity, the Agency sees no reason to
 assume that the facility will not
 continue to manage its wastewater
 treatment sludges from the production
 of methyl chloride in this manner.
  Based on an analysis of potential risks
 associated with current management
 practices, EPA is proposing not to list as
 hazardous wastewater treatment sludges
 from the production of methyl chloride.
The Agency found no significant risks
 arising from the on-site landfill
 management scenario. The only possible
 concern arises from the marginal risk
associated with arsenic, which falls at
the risk level generally identified by
EPA for listing a waste as hazardous,
when assuming a DAF of 5. The Agency
believes this assumption is reasonable
                        for an unlined landfill, and likely
                        results in an overestimate of risk for the
                        management practice identified by EPA
                        (i.e., an on-site landfill that operates
                        with a clay liner and leachate collection
                        at a single facility).
                          The Agency requests comments on
                        the approach taken to determine a no-
                        list proposal for hazardous wastewater
                        treatment sludges from methyl chloride
                        manufacturing.

                        5. Allyl Chloride Wastewater Treatment
                        Sludges
                        a. How Is EPA Proposing To Regulate
                        Allyl Chloride Wastewater Treatment
                        Sludges?
                          EPA is proposing not to list as
                        hazardous sludges generated from
                        treating wastewaters associated with the
                        manufacture of allyl chloride. This
                        wastestream does not meet the criteria
                        set out at 40 CFR 261.11 (a) (3) for listing
                        a waste as hazardous. It does not pose
                        a substantial present or potential threat
                        to human health or the  environment.
                        The Agency has identified no risks of
                        concern associated with the current
                        management of the waste.
                        b. What Information Led EPA To
                        Propose To Not List as Hazardous Allyl
                        Chloride Wastewater Treatment
                        Sludges?
                          Wastewater treatment sludges from
                        allyl chloride production are generated
                        at a single facility. The sludges are
                        generated from the facility's centralized
                        wastewater treatment system. This
                        wastewater treatment system is a non-
                        dedicated system in that wastewaters
                        from the facility's multiple production
                        processes are discharged to the single
                        system for combined treatment.
                        Wastewaters from the production of
                        allyl chloride contribute less than two
                        percent to the system's total sludge
                        loading. According to the RCRA Section
                        3007 survey response, the sludge
                        generated from the facility's wastewater
                        treatment system is incinerated on site
                        in a non-hazardous waste incinerator.
                          During the investigations undertaken
                        in support of the listing determinations,
                        EPA collected one sample of this sludge.
                        Two duplicate TCLP analyses were
                        performed using the sample collected.
                        The sample also was analyzed for total
                        concentrations of dioxins and furans.
                        The TCLP analyses indicated the
                        presence of no TCLP constituents above
                        regulatory levels. The total arsenic
                        concentration in the waste was 11.7 mg/
                        kg, while the total dioxin (TEQ/TCDD)
                        concentration was 11.79 ng/kg.
                          The Agency does not anticipate any
                       significant risk  from the incineration of
                       allyl chloride wastewater treatment
 sludge in a non-hazardous waste
 incinerator, since both the total arsenic
 level47 and the total dioxin level48
 detected in the sludge are well within
 the range of background levels of those
 constituents in soils.
   The Agency did not-conduct an
 analysis of risk associated with other
 management practices, based upon the
 fact the waste is generated by a single
 facility and currently is not managed in
 a manner other than non-hazardous
 waste incineration.
   Given that wastewater treatment
 sludges from allyl chloride production
 are generated by a single facility, that
 the sludge generated is the product of a
 facility-wide non-dedicated (i.e., not
 process-specific) wastewater treatment
 systemrand that no significant risks are
 posed by the waste attributable to the
 allyl chloride production process, the
 Agency is proposing not to list this
 waste as hazardous.
   The Agency requests comments on
 the approach taken to determine to
 propose not to list as hazardous
 wastewater treatment sludges from allyl
 chloride manufacturing.
 F. Constituents Proposed for Addition to
 Appendix VIII to 40 CFR Part 261
   Two of the constituents of concern
 that are present in the chlorinated
 aliphatic wastewaters (K173) and the
 EDC/VCM wastewater treatment sludges
 (K174) proposed to be listed as
 hazardous waste do not currently
 appear on the list of hazardous
 constituents at 40 CFR part 261,
 appendix VIII. Therefore, EPA is
 proposing to add these two constituents,
 octachlorodibenzo-p-dioxin (OCDD) and
 octachlorodibenzofuran (OCDF), to
 appendix VIII. OCDD and OCDF are
 members of the large family of
 polychlorinated dioxins and furans.
 Certain of these compounds, most
 notably, 2,3,7,8 TCDD, have been shown
 to be extremely toxic.
   As discussed  in section III.D of
 today's proposed rule, the Agency's risk
 assessment found significant risks
 associated with the presence of dioxins
  "Alkhatib. Eid, and O'Connor, Timothy,
 "Background Levels of Priority Pollutant Metals in
 Soil. American Environmental Laboratory, Vol. 10.
 No. 3. April. 1998.
  Hunter. Philip M., "Air-Force Wide Background
 Concentrations of Inorganics Occurring in Ground
 Water and Soil," Proceedings from the Fourteenth
 Annual Waste Testing and Quality Assurance
 Symposium. Pp. 73-77, 1998.
  Welch, Alan H., Lico, Michael S., and Hughes,
Jennifer L., "Arsenic In Ground Water of the
 Western United States." Ground Water. Vol. 26, No.
 3. May/June, 1988.
  48 See Table 4-4 of "Risk Assessment Technical
Background Document for the Chlorinated
Aliphatlcs Listing Determination," EPA, June 25,
 1999.

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                 Federal  Register/Vol. 64. No.  164 /Wednesday,  August 25, 1999/Proposed Rules         46517
  in both chlorinated aliphatic
  wastewaters and EDC/VCM wastewater
  treatment sludges. In the case of our
  analysis of risk for both categories of
  waste, the dioxin/furan concentrations
  were measured on a TCDD TEQ basis.
  As previously discussed in today's
  proposed rule, TCDD TEQ
  concentrations are calculated by
  multiplying each 2,3,7,8 congener by
  the appropriate TEF, and then summing
  the resultant concentrations to come up
  with a TCDD TEQ value. OCDD and
  OCDF are part of this calculation.
    Available data indicate that 2,3,7,8-
  substituted congeners of chlorinated
  dibenzo-p-dioxin and dibenzofurans
  have toxic effects similar to 2,3,7,8,-
  TCDD. Data available from in vivo and
  in vitro studies reveal a strong structure-
  activity relationship, in which the
  2,3,7,8-substituted congeners are much
.  more biologically active than other
  congeners. Both OCDD and OCDF are
  2,3,7,8-substituted congeners. Available
  data also show that the relative
  responses of different PCDDs and PCDFs
  are generally consistent across a variety
  of toxicity end points.49 In regard to
  OCDD specifically, test animals
  exhibited initial signs of "dioxin
 toxicity" in a subchronic study of mice
 exposed to OCDD at low levels.50
   EPA also points out that the oral slope
 factors for OCDD and OCDF (calculated
 by multiplying the cancer slope factor
 for 2,3,7,8 TCDD by the TEFs for  OCDD
 and OCDF, which are both 0.000151) are
 relatively high  (15/(mg/kg)/day)
 compared to the oral slope factor of
 other hazardous constituents currently
 listed in appendix VIII to 40 CFR 261
 (e.g., arsenic has an oral slope factor of
 1.5/(mg/kg)/day).
   Therefore, we have concluded that,
 based upon sufficient evidence to show
 that OCDD and OCDF are hazardous
 constituents and based upon the fact
 that OCDD and OCDF are the only
 congeners that make up TCDD TEQ that
 are not currently listed in appendix VIII,
 OCDD and OCDF should be added to
 appendix VIII of 40 CFR part 261. The
 Agency requests comment on its
 proposal to add OCDD and OCDF to the
  49 U.S. Environmental Protection Agency. 1989
Update to the Interim Procedures for Estimating
Risks Associated with Exposures to Mixtures of
Chlorinated Dibenzo-p-Dioxins and -Dibenzofurans
(CDDs and CDFs). Washington. D.C.: Risk
Assessment Forum, March, 1989. EPA/625/3-89/
016.
  s°Couture, L.A., M.R. Elwell. and L.S. Birnbaum.
"Dioxin-like Effects Observed in Male Rats
Following Exposure to Octachlorodibenzo-p-dioxin
(OCDD) during a 13-week Study." Toxicology and
Applied Pharmacology, Vol. 93, Pp 31-46, 1988.
  51 Using the toxicity equivalency factor (TEF)
developed by the World Health Organization, see
section III.D.l.g.ii of today's proposed rule for
discussion of TEFs.
  list of hazardous constituents in
  appendix VIII to 40 CFR 261.

  IV. Economic Analysis

  A. What Is the Purpose of the Economic
  Analysis?
    The primary purpose of the economic
  analysis presented in the "Economic
  Background Document, "is to estimate
  potential industry compliance costs
  associated with this listing  proposal.
  Secondary purposes are to provide
  descriptive information about the
  economic (industry) sectors affected,
  and about the economic activities
  involving chlorinated aliphatic
  hydrocarbon chemicals (CAHCs). The
  Economics, Methods, and Risk
  Assessment Division (EMRAD) of EPA's
  Office of Solid Waste (OSW) conducted
  the economic analysis.  The "Economic
  Background Document"is available to
  the public from the RCRA docket (refer
  to the introduction to this preamble for
  instructions on how to obtain a copy).
  The findings of the economic study are
  summarized in this section of the
  preamble. References to statements
  below pertaining to facts, data,
  assumptions and other types of
  information, are identified in the
  document.

  B. How May the Public Participate in the
  Economic Analysis?
   The USEPA encourages the public to
 provide comments and suggestions
 about the design, accuracy,
 representativeness and completeness of
 the "Economic Background Document."
   In preparing the Economic
 Background Document,  the EPA
 preferred to the maximum extent
 possible, to use publicly-available rather
 than confidential business information
 (CBI) as information and data sources, to
 facilitate transparency for public review
 and comment. However, some
 information was designated by survey
 companies as CBI when  collected in the
 1992 and 1997 Section 3007  surveys
 administered by EPA (described
 elsewhere in this preamble).
 Consequently, the background data and
 information available to  the EPA during
 development of this listing proposal
 also consisted of CBI information. In
 order to minimize reliance on CBI data,
 and to exhaust available  public
 information sources, EPA consulted
 many other databases as  supplements
 and substitutes to the RCRA Section
 3007 survey, in conducting the
 economic study.
  EPA particularly requests written
comments from the public on the
information elements listed below
pertaining to the economic analysis
   presented in the "Economic Background
   Document:"

    1. Study Design: Suggestions for
   modifications and improvements to the
   scope, methodology, and organization of the
   Economic Background Document (e.g., 30-
   year cost annualization -period-of-analysis"
   applied).
    2. Facility Universe: Correct number and
   locations of CAHC manufacturing and any
   other types of facilities and entities
   potentially affected by the RCRA listing
   proposal.
    3. Affected Wastes: Correct average annual
  quantities, types and industrial source
   (origin) of potentially affected CAHC
  manufacturing wastes.
    4. Industry Profile: Characterization of the
  role, functions and industrial organization
  associated with the production and use of
  CAHCs in the US economy.
    5. Baseline Waste Management:
  Characterization of baseline (current) waste
  management practices associated with CAHC
  manufacturing wastes (both onsite and offsite
  management practices), including the types
  and  relative waste quantities managed, types
  of waste management units, costs of waste
  management ($/ton basis), waste
  commingling and segregation, etc. In
  particular, there is uncertainty in the Section
  3007 survey data, about the exact number
  and sizes of wastewater management tanks
  used by CAHC manufacturing facilities.
   6.  Compliance Waste Management:
  Adaptation of CAHC manufacturing facilities
  to the RCRA listing proposal if finalized,
  such as changes in CAHC manufacturing
  plant & equipment, facility layout,
 production processes and methods, business
 arrangements, CAHC product mixes, etc.
 What are possible operating consequences to
 waste management facilities for meeting
 K175 waste pH and sulfide  landfill
 restrictions?
   7. Facility Process Modifications:
 Identification and dollar value of lump-sum
 capital investment costs required (per
 industrial operating unit or facility).
   8. Unit Costs: Overall representativeness of
 unit costs applied to the universe of CAHC
 manufacturing facilities for industrial waste
 management, involving both non-hazardous
 and hazardous waste handling.
   9. Impact Benchmarks:The
 appropriateness of the alternative company
 financial benchmarks (e.g., annual sales
 revenues, annual profits, capital
 expenditures, short-term credit) presented in
 this study, and of other benchmarks not
 presented, for purpose of providing
 measurement references relative to assessing
 the dollar magnitude of the estimated
 industry compliance costs.
   10.  Supporting Data: The data applied in
 the economic study are from sources
 published over a number of years, and for
 some key data elements, are  more  than five
 years old (e.g., during preparation  of this
 study, the US Bureau of Census' 1997 Survey
 of Manufacturers data reports were not yet
 available).
   11. Other Considerations: Any other
comments pertaining to other aspects of the
economic study, or to topics  which have
been omitted or are outside the scope of the

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Federal Register/Vol. 64, No.  164/Wednesday,  August  25,  1999/Proposed  Rules
study, irrelevant to assessing the economic
Impact of the listing proposal.
C. How Are Chlorinated Aliphatic
Chemicals Used in the Economy?
  Chlorinated aliphatic hydrocarbon
chemicals (CAHCs) entered into
commerce in the US in the early 1920s,
and as of 1994, approximately 38 billion
pounds of 50 different commercially
significant CAHCs were manufactured
by 23 chemical plants (facilities) in the
United States. The US production of
CAHCs has grown an average annual
rate of 4,4 percent over the last 30 years.
  CAHCs are a group of organic
chemicals—most of which are colorless
liquids at room temperature—primarily
used as intermediate feedstocks for the
production of polyvinyl chloride (PVC)
plastics; CAHCs are also used directly in
liquid form as various types of solvents,
as intermediates for the production of
other types of chemicals, and in
assorted other commercial use
categories. As of 1996. three CAHCs—
ethylene dichloride, vinyl chloride,
methyl chloride—were on the list of
top-50 chemicals produced in the
United States.
D. Where Are CAHCs Manufactured in
the United States?
  In conjunction with contacts of
industry representatives, EPA identified
an initial subset of industrial facilities
relevant to the scope of the listing
proposal, according to both the (a) types
of chemical products manufactured, as
well as the (b) types of industrial
wastestreams generated from the
chemical manufacturing processes. EPA
identified a total of 28 facilities in the
1992 Section 3007 industry survey, and
a total of 26 facilities in the 1997 follow-
up survey, as a result of two facility
                        closures in the interim period. Three of
                        the 26 facilities were discovered to be
                        either "de minimus" producers of
                        CAHCs, or double-counted in the
                        survey, which resulted in a final subset
                        of 23 relevant CAHC manufacturing
                        facilities.
                         The relevant subset of 23 CAHC
                        manufacturing facilities surveyed in
                        USEPA-OSW's 1997 survey are located
                        in eight states (Kansas, Kentucky,
                        Louisiana, Maryland, Michigan, New
                        York, Tennessee, and Texas), and
                        employ an average of over 700
                        employees per facility. Total
                        employment for all 23 facilities is about
                        19,000 employees, and the total
                        employment associated with the 16
                        parent companies which own these 23
                        facilities is much larger, estimated at
                        526,700 employees.
                        E. Have CAHCs Been Produced
                        Historically in Other Locations in the
                        United States?
                         In addition to current databases, there
                        are assorted documents which contain
                        historical information about the CAHC
                        production industry in the United
                       States. Historically, CAHCs have been
                       manufactured and/or used as feedstocks
                       and intermediates in chemical
                       production plants in at least 15 states in
                       the US. The historical data on the
                       number and location of CAHC
                       production facilities serves to  illustrate
                       the dynamic business activity in this
                       industry sector. As late as 1975, CAHCs
                       were produced in the US by 32
                       companies in 58 plant locations.
                       F. What Are the Estimated Potential
                       Industry Costs of This Listing?
                         There are two associated categories of
                       potential compliance costs for CAHC
 manufacturers under this listing
 proposal: (a) process wastewater listing
 costs, and (b) wastewater treatment
 sludge listing costs. These costs are
 incremental to current waste
 management costs in this industry, in
 the sense that all CAHC manufacturing
 facilities are currently regulated under
 RCRA (i.e., as chlorinated aliphatic
 manufacturers via the existing RCRA
 F025 and F026 wastecodes, among
 others), and some facilities-currently
 manage most or all of their CAHC
 manufacturing wastes as hazardous.
 Consequently, this listing proposal will
 not have a full incremental impact on
 these facilities, and the marginal impact
 on their existing operations in relation
 to current RCRA compliance and
 hazardous waste handling practices may
 be less than it otherwise would be if
 these companies and facilities did not
 have experience with baseline RCRA
 waste management practices.
  As summarized in Table IV-1 below,
 EPA estimates the total industry
 compliance cost—excluding paperwork
 burden as separately estimated in the
 Information Collection Request—
 associated with the two wastestream
 components of the listing proposal (i.e.,
 sludges and wastewaters), at $2.355
 million in average annual cost, for
 annual waste management in
 conformance with the terms  of the
 listing proposal. This total cost consists
 of an estimated $1.320 million in initial
capital expenditures (30-year
annualized equivalent of $0.046
million), and an estimated $2.309
million in recurring annual costs.
      TABLE IV-1.—SUMMARY OF ESTIMATED  INDUSTRY COMPLIANCE COSTS FOR THE RCRA LISTING PROPOSAL;
    WASTEWATER TREATMENT SLUDGES AND WASTEWATERS. AVERAGE ANNUAL EQUIVALENT TOTAL INDUSTRY COST
Item
A.
A1
A2


B.
B1
B2
B3
B4
B5



c

Type of CAHC facility potentially affected by the proposed RCRA listing options
SLUDGE LISTING ESTIMATED COSTS:
Non-landfilled EDC/VCM sludge 	
VCM— A process w/mercury catalyst 	

Subtotal sludge costs 	
WASTEWATER LISTING ESTIMATED COSTS:
Tank fixed roof + valve . 	
Tank roof vent + carbon control 	
Tank "Subpart CC" ancillary costs* 	
Initial waste testing fordioxins 	
Annual waste retesting for dioxins 	

Subtotal wastewater costs 	

SLUDGE + WASTEWATER COSTS (column totals) . 	 	

Initial
capital
costs
($ lump-sum)
$0
C

I
1,084,600
150,900
(
84,500
C

1,320,000

1,320,000

Recurring
annual
O&M costs
($/year)
$1 333 000
209,000

) 1 ,542,000
81 ,600
591 ,200
23700
0
70,400

766,900

2 309 000


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                 Federal Register/Vol. 64, No.  164/Wednesday. August 25, 1999/Proposed  Rules
                                                                      46519
  TABLE IV-1.—SUMMARY OF ESTIMATED INDUSTRY COMPLIANCE COSTS FOR THE  RCRA  LISTING  PROPOSAL- WASTE-
      WATER TREATMENT SLUDGES AND WASTEWATERS. AVERAGE ANNUAL EQUIVALENT TOTAL  INDUSTRY COST—Contin-
      ued

Item



Type of CAHC facility potentially affected by the proposed RCRA listing options

Total annualized equivalent cost 	
Initial
capital
costs -
($ lump-sum)

Recurring
annual
O&M costs
($/year)
2,355,000
  V. Proposed Treatment Standards
  Under RCRA's Land Disposal
  Restrictions

  A. What Are EPA's Land Disposal
  Restrictions (LDRs)?
    The RCRA statute requires EPA to
  establish treatment standards for all
  wastes destined for the land disposal.
  These are the so called "land disposal
  restrictions" or LDRs. For any
  hazardous waste identified or listed
  after November 8, 1984, EPA must
  promulgate these LDR treatment
  standards within six months of the date
  of identification or final listing (RCRA
  Section 3004(g) (4), 42 U.S.C. 6924(g)(4))
  RCRA also requires EPA to set as these
  treatment standards "*' * * levels or
  methods of treatment, if any, which
 substantially diminish the toxicity of
 the waste or substantially reduce the
 likelihood of migration of hazardous
 constituents from the waste so that
 short-term and long-term threats to
 human health and the environment are
 minimized." (RCRA Section 3004(m)(l),
 42 U.S.C. 6924(m)(l)).
   Wastes that meet treatment standards
 established by EPA may be land
 disposed. Wastes that do not meet these
 standards are prohibited from land
 disposal (except in so-called no-
 migration units). Each waste proposed
 for listing as hazardous in this rule will
 be subject to all the land disposal
 restrictions on the same day their
 respective listing becomes effective.
 B. How Does EPA Develop LDR
 Treatment Standards?
  To establish LDR treatment standards,
 EPA first identifies the best
 demonstrated available technology
 (BOAT) for the hazardous constituents
 present in the hazardous waste, and
 then determines what constituent
 concentrations can be achieved by the
 technology or technologies identified as
 BOAT.
  EPA typically has established
 treatment standards  based on
 performance data from the treatment of
 the waste at issue, if such data are
available, and also from the treatment of
wastes with similar chemical and
physical characteristics or similar
  concentrations of hazardous
  constituents. Treatment standards
  typically cover both wastewater and
  nonwastewater waste forms on a
  constituent-specific basis. The
  constituents selected for regulation
  under the LDR program are not
  necessarily limited to those present in a
  proposed listing, but also may include
  those constituents or parameters that  ,
  will ensure that treatment technologies
  are operated properly. For listed waste
  EPA identifies these as "regulated
  constituents" and they appear
  individually in the Table at 40 CFR
  268.40, along with their respective
  treatment standards.
   EPA may develop and promulgate
  either technology-specific treatment
  standards or numerical treatment
  standards. Should EPA elect to use
  technology-specific standards, all
 wastes that meet the listing designations
 would have to be treated by the
 technology or technologies specified
 before disposal. These technologies are
 also identified in the Table at §268.40
 and are further described in §268.42.
 Should EPA elect to use numerical
 treatment standards, the Agency allows
 the use of any technology (other than
 impermissible dilution) to comply with
 the treatment standards.
   After developing the LDR treatment
 standards, we must also determine if
 significant treatment capacity is
 available to treat the expected volumes
 of wastes. If so, the LDR treatment
 standards become effective essentially at
 the same time a listing does. If not, EPA
 may grant up to a two-year national
 capacity variance (NCV) during which
 time the LDR treatment standards are
 not effective.
   For a more detailed overview of the
 Agency's approach for developing
 treatment standards for hazardous
 wastes, see the final rule on solvents
 and dioxins (51 FR 40572, November 7,
 1986) and section III. A.I of the
 preamble to the final rule that set land
 disposal restrictions for the "Third
 Third" wastes (55 FR 22535, June 1,
 1990). EPA also has explained  its BOAT
procedures in "Best Demonstrated
Available Technology (BOAT)
Background Document for Quality
  Assurance/Quality Control Procedures
  and Methodology (EPA/OSW, October
  23, 1991)" . This document is available
  in the docket supporting this
  rulemaking.

  C. What Kind of Treatment Standards
  Are Proposed?
    EPA has gathered data on waste
  characteristics and current management
  practices for wastes proposed in this
  action as part of the administrative
  record for this rule, and has evaluated
  these data to develop specific treatment
  standards. An examination of the
  constituents that are the basis of the
  proposed listings shows that the Agency
  has previously developed numerical
  treatment standards for most of the
  constituents of concern. After reviewing
  the available characterization data and
  the available information on waste
  management practices for these wastes
  proposed for listing, EPA has
  determined that it is technically feasible
  and justified to apply existing universal
  treatment standards (UTS) to the
  regulated hazardous constituents of
  concern in the wastes proposed to be
 listed as K173 and K174. For K175, EPA
 is proposing a metals recovery
 requirement as the treatment standard,
 namely roasting and retorting/Although
 the mercury in K175 would be
 recovered, other treatment residuals will
 exist. For these residuals, we are
 proposing that existing UTS will be
 applicable.
  Available information also shows that
 these wastes and the treatment residuals
 can be managed in existing treatment
 and reclamation units that routinely
 manage similar or as-difficult-to-treat
 hazardous wastes that currently are
 prohibited from land disposal. The
 BOAT background document provides
 further information on EPA's rationale
 for applying UTS  to these wastes and
 the treatment standard of metals
 recovery to K175.  Also see LDR Phase
 II final rule, 59 FR 47982, September 19,
 1994, for a further discussion of UTS.
  For proposed K173 and K174, EPA is
 proposing to regulate specific
 constituents from each of these
 hazardous wastes. A list of the proposed
regulated hazardous constituents and

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 the proposed treatment limits can be
 found in the following preamble section
 and in the proposed regulatory Table
 268.40—Treatment Standards for
 Hazardous Wastes. If EPA makes a final
 decision to list the identified wastes,
 these constituents and standards would
 apply.
   EPA has provided in the BOAT
 background document a review of
 thermal and nonthermal technologies
 that can be used to meet the proposed
 numerical concentration limits for
 proposed K173 and K174, assuming the
 design and operation of these
 technologies are optimized. Since EPA
 Is proposing numerical concentration
 limits, the use of other technologies
 capable of achieving the proposed
 treatment standards is allowed, except
 for those treatment or reclamation
 practices constituting land disposal or
 impermissible dilution (see 40 CFR
 268.3). As noted above, EPA is
 proposing a specified technology-
 specific treatment standard for K175.
 K175 waste would therefore have to be
 treated by the required technology and
 the residues thereof or subsequent
 residues would have to meet numerical
 UTS concentration limits.52
 D. Other LDR-Related Provisions
  We propose that the provisions in 40
 CFR 268.45 would also be applicable for
 the treatment and disposal of hazardous
 debris contaminated with proposed
 K173.  K174, and K175. Hazardous
 debris treated in accordance with the
 provisions of 40 CFR 268.45 may be
 allowed for land disposal in a hazardous
 waste disposal facility. As a result,
 debris contaminated with proposed
 K173,  K174, and K175 would be
 required to be treated prior to land
 disposal, using specific technologies
 from one or more of the following
 families of debris treatment
 technologies: extraction, destruction, or
 immobilization. Residuals generated
 from the treatment of debris
 contaminated with proposed K173,
 K174. or K175 will have to meet the
 applicable UTS limits proposed today.
 See 57 FR 37277, August 18,1992, for
 additional information on the
 applicability, scope, and content of the
 hazardous debris provisions.
  We note that, when the listings
 proposed today become final, the
  82 There are two exceptions. Where the treatment
technology is not appropriate to the waste.
regulations provide a petition process whereby the
generator or treatment facility may petition the
Administrator for a variance. See 40 CFR 268.44. In
addition, persons can petition the Administrator for
an alternate treatment method by showing that the
alternate method can achieve a measure of
performance equivalent to the method specified by
rule.
                        alternative soil treatment standards in
                        40 CFR 268.49 would be available for
                        any soils contaminated with the newly
                        listed wastes. Soils that must meet LDRs
                        before land disposal may be treated to
                        the levels in the alternative soil
                        treatment standards as long as the soils
                        will not be used in a manner
                        constituting disposal. Even though EPA
                        is proposing a method of treatment for
                        K175, the waste contains an analyzable
                        hazardous constituent. Consequently,
                        the alternative treatment standards may
                        apply and specify that the analyzable
                        constituent must be at specified levels
                        for soil contaminated with the waste to
                        be disposed. See 268.49 (c) (3) (B),
                        promulgated at 63 FR 28751. Such soils
                        can only be land disposed  (here,
                        recycled by being placed on the land) if
                        they first meet UTS. See 63 FR 28609-
                        28610 (May 26, 1988).
                          A facility is not required to use these
                        alternative soil treatment standards and
                        may elect to comply with the traditional
                        LDR treatment standards for process
                        waste. The choice of whether to do so
                        potentially impacts how many
                        constituents must meet LDR treatment
                        standards.  If a site chooses to meet the
                        alternative soil treatment standards and
                        their soils are contaminated with a
                        listed waste, then they are required to
                        treat both the regulated hazardous
                        constituents specified in 268.40 and
                        also any underlying hazardous
                        constituents. Potential underlying
                        hazardous constituents are listed in the
                        UTS Table at 268.48. However, if the
                        traditional treatment standards are
                        applied to a soil contaminated with a
                        listed waste, then only the regulated
                        constituents specified in 268.40 must
                        meet the treatment standards. For
                        further discussion of the alternative soil
                        treatment standards, please refer to the
                        final Phase IV LDR rule (63 FR 28556,
                        28609, May 26, 1998) and the
                        subsequent clarification notice (64 FR
                        25410-25411. May 11, 1999).
                         Lastly, because land disposal also
                        includes placement in injection wells
                        (40 CFR 268.2(c))  application of the land
                        disposal restrictions to proposed K173,
                        K174, and K175 requires the
                        modification of injection well
                       requirements found in 40 CFR 148. We
                       propose that K167 and K168 be
                       prohibited from underground injection.
                       See 40 CFR 148. Therefore,  wastes
                       proposed to be listed as K173, K174,
                       and K175 may not be underground
                       injected unless they have been treated
                       in compliance with the LDR treatment
                       standards or a no migration petition for
                       these wastes has been approved. •
 E. What Standards Is EPA Proposing for
 K173?
   EPA is proposing to apply existing
 Universal Treatment Standards to
 proposed K173 wastes. We have
 examined the constituents that comprise
 the basis of the proposed listing and
 identified the presence of those other
 constituents near on in excess of current
 numerical universal treatment
 standards. Wastes that exceed these
 levels require treatment of the
 constituents to diminish the toxicity of
 the waste and to reduce the likelihood
 of migration of the hazardous
 constituents. Based on this examination,
 we propose treatment standards for
 bis(2-chloroethyl)ether, chloroform,
 pentachlorophenol, phenol, 2,4,6-
 trichlorophenol, chromium (total), and
 nickel in addition to
 tetrachlorodibenzodioxins,
 pentachlorodibenzodioxins,
 hexachlorodibenzodioxins,
 heptachlorodibenzodioxins,
 tetrachlorodibenzofurans,
 pentachlorodibenzofurans,
 hexachlorodibenzofurans,
 heptachlorodibenzofurans, OCDD, and
 OCDF in proposed K173.
   Existing LDR standards for the wastes
 that contain chlorinated dibenzo-para-
 dioxins and dibenzofurans are
 expressed in terms of all
 tetrachlorodibenzo-p-dioxins,
 pentachlorodibenzo-p-dioxins,
 hexachlorodibenzo-p-dioxins,
 tetrachlorodibenzofurans,
 pentadibenzofurans,
 hexachlorodibenzofurans, OCDD,  and
 OCDF. Today's notice proposes
 treatment standards for five additional
 dioxin/furan congeners, namely
 1,2,3,4,6,7,8-heptachlorodibenzo-p-
 dioxin, 1,2,3,4,6,7,8-
 heptachlorodibenzofuran, 1,2,3,5,7,8,9-
 heptachlorodibenzofuran, OCDD, and
 OCDF. We are doing so because these
 constituents are present at
 concentrations that present significant
 risks should proposed hazardous waste
 K173 be mismanaged.
  For proposed K173 nonwastewaters,
 we propose that the LDRs for the three
 new congeners (1,2,3,4,6,7,8-
 heptachlorodibenzo-p-dioxin,
 1,2,3,4,6,7,8-heptachlorodibenzofuran,
 1,2,3,5,7,8,9-heptachlorodibenzofuran,
 OCDD, and OCDF) be set at the
 quantitation limits of method 8280A.
These quantitation limits  are achievable
routinely, and being 3 to 4 times the
detection limit of residues from
combustion, they are a reasonable
approximation of 2.8 times the method
detection limit normally used to
develop treatment standards from
detection limit data to account for

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                Federal Register/Vol. 64, No.  164/Wednesday,  August 25, 1999/Proposed Rules
                                                                       46521
  potential treatment variability.33 Since
  method 8280A was first developed, the
  more sensitive high-resolution mass
  spectrometry method 8290 has been
  developed. Method 8290 may achieve
  detection limits orders of magnitude
  more sensitive than Method 82 80A.
  However, we lack actual treatment
  performance data for these wastes using
  method 8290. Further, because of the
  trace levels of dioxins/furans that
  method 8290 is capable of detecting, we
  can not presume that combustion would
  achieve the much lower non-detectable
  levels of method 8290. Therefore, we are
  proposing to base treatment standards
  for the five congeners cited above on the
  more widely available method 8280A.
  We specifically invite data to be
  submitted on the levels that can be
  achieved using method 8290.
   From past trial burns, we have
•  confidence that incineration has been
 fully demonstrated for treating dioxin-
  containing wastes. As explained in 1989
  solvents and dioxin rule, Method 8280A
  failed to detect chlorinated dibenzo-p-
  dioxins and dibenzofurans in residues
 from trial burns. This has led the
 Agency to conclude that the residual
 levels of chlorinated dibenzo-p-dioxins
 and dibenzofurans that remain after
 treatment would be well below the
 levels proposed. See 51  FR 1734,
 January 14, 1986. Therefore, for the
 three new congeners, we are proposing
 standards based on these data showing
 that high temperature thermal treatment
 achieved destruction of these
 constituents to levels below the stated
 quantitation limits of method 8280A.
   Foe, proposed K173 wastewaters, we
 propose that the UTS treatment level of
 0.000035 mg/L for
pentachlorodibenzofuran be transferred
to 1,2,3,4,6,7,8-heptachlorodibenzo-p-
dioxin, 1,2,3,4,6,7,8-
heptachlorodibenzofuran, and
 1,2,3,5,7,8,9-heptachlorodibenzofuran.
Pentachlorodibenzofuran is a structural
homologue of these constituents with
similar physical properties, which
allows us to assume similar treatment
efficiencies. Similarly, we propose that
the UTS treatment level of 0.000063 mg/
L for tetrachlorodibenzofuran be
transferred to OCDD and OCDF. For all
other dioxin/furan congeners, we
propose to transfer the current,
corresponding universal treatment
standards.
  For the specific numerical standards
proposed to be applicable to proposed
K173, see the proposed amendments to
  53 See Best Demonstrated Available Technology
(BOAT) Background Document for Quality
Assurance/Quality Control Procedures and
Methodology. EPA, October 23,1991.
  40 CFR 268.40 at the end of this
  preamble. We request comment on the
  proposed treatment standards for
  proposed K173.         '-

  F. What Standards Is EPA Proposing for
  K174?
    EPA is proposing to apply existing
  Universal Treatment Standards (UTS) to
  these wastes. We have examined the
  constituents that comprise the basis of
  the proposed listing and identified the
  presence of those other constituents
  near on in excess of current numerical
  universal treatment standards. Waste
  that exceed these levels require
  treatment of the constituents to
  diminish the toxicity of the waste and
  to reduce the likelihood of migration of
  the hazardous constituents. Based on
  this examination, we propose that
  wastes proposed to be listed as K174 be
  treated for arsenic, tetrachlorodibenzo-
  p-dioxins, pentachlorodibenzo-p-
  dioxins, hexachlorodibenzo-p-dioxins,
  heptachlorodibenzo-p-dioxins,
  tetrachlorodibenzofurans,
  pentachlorodibenzofurans,
  hexachlorodibenzofurans,
  heptachlorodibenzofurans, OCDD, and
  OCDF. We are proposing to apply the
  new numerical standards for the five
  new congeners (one
  heptachlorodibenzo-p-dioxin, two
  heptachlorodibenzofurans, OCDD, and
  OCDF), discussed in the  previous
 section, to proposed hazardous waste
 K174 because these constituents are also
 present in proposed K174 wastes at
 significant concentrations that would
 present risks should the wastes be
 mismanaged.
   We request comment on the proposed
 treatment standards for wastes proposed
 to be listed as Kl74.

 G.  What Standards Is EPA Proposing for
 K175?
  Proposed hazardous waste K175 is
 generated from the treatment of catalyst
 change-out wastewaters from the
 chlorination of acetylene on a mercuric
 chloride catalyst. As with the above
 wastes, we have examined the
 constituents that comprise the basis of
 the proposed listing and identified the
 presence of mercury as the only
 constituent that would require treatment
 to diminish the toxicity of the waste and
 to reduce the likelihood of migration.
 Proposed K175 contains in excess of 260
 mg/kg mercury and is greater than one
 percent in organic constituents. This
 type of waste profile is similar to wastes
 that are currently deemed to be
 characteristically hazardous under the
 D009 waste code. Therefore, in
 assessing what type of LDR treatment
standards are warranted for proposed
  K175, we look first to the D009
  treatment standards.
    Current regulations for similar D009
  wastes require either retorting or
  roasting (RMERC) or incineration in
  units operated in accordance with the
  technical operation requirements of 40
  CFR Part 264, Subpart O and Part 265,
  Subpart O (IMERC ). However, current
  regulations do not require combustion
  units to capture and recover mercury
  from the combustion gases produced. If
  all the mercury contained in these
  wastes were combusted without capture
  and removal, the result would be over
  one metric ton per year of mercury
  emissions. Under the upcoming
  revisions to the hazardous waste
  combustion regulations, it is not clear
  that facilities are going to choose to
  employ air pollution control devices
  (capture and removal devices) to
  comply with mercury emission limits.
  They might instead simply choose to
  reduce their feed rate, which will not
.  reduce the total amount of mercury
  emitted over the long term. Given this
  uncertainty about future compliance
  strategies by the hazardous waste
  combustion industry, we are proposing
  that mercury recovery by retorting or
  roasting (RMERC) be the required
  treatment technology for this waste.
  RMERC requires processing in devices
  subject to mercury emission controls
  resulting in mercury capture and
  removal, and also subject to emission
 standards such as the National
  Emissions Standard for Hazardous Air
 Pollutants (NESHAP) for mercury. See
 40 CFR 268.42. For residues of the
 RMERC process, we propose to adopt
 the current standard of 0.20 mg/L TCLP
 mercury.
   The Agency has contacted a treatment
 vendor of RMERC technology who
 indicated that treatment of the subject
 wastes may be difficult, but is
 possible.54 We therefore request
 treatment performance data regarding
the use of retorting for these waste.
  Absent definitive treatment data, we
have considered whether an alternative
treatment standard to retorting might be
feasible to propose for comment. One
alternative is to establish a numerical
concentration limit. Under current
regulations, mercury wastes that are
stabilized are subject to a standard of
0.025 mg/L TCLP mercury. This differs
from the initial option of retorting in
two key respects. First, use of specific
treatment technology would not be
required and, second, the treated waste
or waste residuals would be subject to
a numerical standard about one order of
  "Personal communication with John Boyle,
Bethlehem Apparatus Co.. Inc.

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Federal Register/Vol.  64, No.  164/Wednesday, August 25,  1999/Proposed Rules
 magnitude more stringent—0.2 mg/L for
 retorting residuals under the first option
 vs. 0.025 mg/L for all treatment
 residuals under this second option.
   Without the assurance of treatment
 that a requirement for retorting would
 provide, the tighter standard of 0.025
 mg/L TCLP is appropriate to propose as
 a potential treatment standard. This
 standard would apply to all treatment
 residuals included in the listing
 description for proposed hazardous
 waste K175, regardless of the type of
 treatment used. In practice, this
 standard would involve the
 immobilization of the mercury in the
 waste before land disposal. If
 regulations were to be promulgated in
 this form, the waste could be land
 disposed if a standard of 0.025 mg/L
 TCLP mercury was achieved using any
 technology other than impermissible
 dilution.
   Calculated solubilities of mercury
 sulfide (metacinnabar) as a function of
 pH have revealed that above pH 6.0 the
 presence of sulfide complexes  results in
 significantly increased solubility.55
 Preliminary results from constant pH
 leaching measurements of the subject
 waste, as part of an on-going study, have
 shown similar results.56 At pH  6.0 the
 waste tested leached 0.0058 mg/L.
 However, at pH 10, 1.63 mg/L mercury
 was solubilized. Current landfill
 disposal site conditions for this waste
 are reported to be pH 9.48-9.57 57 Under
 these conditions, mercury in the waste
 would be expected to be mobilized
 especially if excess sulfides were
 present. Therefore, controlled treatment
 and disposal conditions are warranted
 to avoid mobilization of the mercury in
 the waste, which could pose a
 significant threat to human health and
 the environment. To insure operational
 stability of the treatment process and
 proper long-term disposal, EPA
 proposes two conditions as part of the
 LDR treatment standards. First, the
 waste residue generated, if in mercuric
 sulfide form, must itself be pH 6.0 or
 below. We therefore propose that
 mercuric sulfide residues of this waste
  **H, Lawrence Clever, Susan A. Johnson, and M.
Elizabeth Derrick. The Solubility of Mercury and
Some Sparingly Soluble Mercury Salts in Water and
Aqueous Electrolyte Solutions. J. Phys. Chem, Ref.
Data. Vol. 14, No. 3.1985. page 652.
  **Paul Bishop, Renec A. Rauche. Linda A. Rieser.
Mukram T. Suldan. and Jain Zhang: "Stabilization
and Testing of Mercury Containing Wastes," Draft.
Department of Civil and Environmental
Engineering. University of Cincinnati. March 31,
1999. Please note that this is a draft EPA document
not yet peer reviewed. Also, data within the report
1$ still undergoing QA/QC review, and the text,
data, and conclusions in the report may change
before the document is finalized.
 **May 14.1999, landfill parameters, e-mail from
Mitch Hahn, Waste Management.
                        be treated to attain a pH of less than or
                        equal to 6.0. Second, if proposed K175
                        wastes are to be co-disposed in a landfill
                        with other wastes, co-disposal will be
                        restricted to wastes with similar pH (i.e.,
                        not greater than 6.0). To comply with
                        these requirements disposal facilities
                        would be required to certify and
                        maintain operating records available for
                        inspection of codisposed wastes to
                        demonstrate compliance.
                          Currently, the wastes proposed to be
                        listed as K175 are landfilled after
                        treatment has converted mercuric
                        chloride in wastewaters to mercuric
                        sulfide.  We believe significant
                        opportunities exist for source reduction
                        and waste minimization to reduce or
                        eliminate the generation of this waste.
                        For example, the need to hydroblast
                        spent mercuric chloride catalyst  from
                        reactors could be eliminated by internal
                        segmentation of the reactor bed that
                        would allow the segments to be sent
                        intact for mercury recovery. Thus,
                        generation of the waste could  be
                        eliminated or significantly reduced.
                        Beyond  modifications to the physical
                        plant, the treatment of the wash waters
                        could be modified to incorporate
                        addition of caustic and  organic phase
                        separation. This would  result  in a
                        mercuric oxide sludge more amenable to
                        recovery by retorting prior to sulfide
                        treatment of the resulting brine. As a
                        result of such changes, a smaller volume
                        of mercuric sulfide sludge with reduced
                        organic content would be generated, as
                        would a larger volume of a more easily
                        recoverable mercuric oxide sludge.
                         We request treatment performance
                        data on the treatment standards
                        proposed and on other alternative
                        treatment technologies that would meet
                        the statutory criteria for all LDR
                        standards "minimizing threats to human
                        health and the environment by
                        reductions in the toxicity or mobility of
                        the wastes through the treatment
                        process.  We also request comment on
                        the feasibility of source reduction and
                        waste minimization alternatives
                        described above.

                        H. What  Other Land Disposal
                       Restrictions Aspects Are There to the
                       Proposal?
                         EPA is proposing to add the
                       numerical standards derived for the
                        1,2,3,4,6,7,8-heptachlorodibenzo-p-
                       dioxin, 1,2,3,4,6,7,8-
                       heptachlorodibenzofuran, 1,2,3,4,7,8,9-
                       heptachlorodibenzofuran,
                        1,2,3,4,6,7,8,9-octachlorodibenzo-p-
                       dioxin (OCDD) and  1,2,3,4,6,7,8,9-
                       octachlorodibenzofuran  (OCDF) to the
                       Table of Universal Treatment Standards
                       (UTS) at 40 CFR 268.48.  These
                       constituents have been shown to"
  represent significant risks to human
  health or the environment in the risk
  assessment accompanying this proposal,
  and their presence in other wastes
  should be mitigated to avoid similar
  risks. If promulgated, all characteristic
  wastes which have these constituents as
  underlying hazardous constituents
  above the UTS thus will require
  treatment of those constituents before
  land disposal.
    Furthermore, we are proposing that
  the constituents 1,2,3,4,6,7,8-
  heptachlorodibenzo-p-dioxin;
  1,2,3,4,6,7,8-heptachlorodibenzofuran,
  1,2,3,4,7,8,9-heptachlorodibenzofuran;
  OCDD; and OCDF be added to the list
  of regulated constituents in hazardous
  waste F039 multisource leachate. F039
  applies to multiple listed hazardous
  waste landfill leachates in leu of the
  original waste codes, and F039 wastes
  are subject to all numerical treatment
 standards applicable to all listed wastes.
 To maintain regulatory consistency with
 this regulatory architecture and the
 implementation benefits of having one
 waste code for multisource leachate, the
 treatment standards for F039 are
 updated each time a new LDR standard
 is developed for listed wastes. As a
 result, if today's proposal is ultimately
 promulgated, all leachate (liquids that
 have percolated through land disposed
 wastes) resulting from the disposal of
 more than one restricted hazardous
 waste will have to meet UTS for all
 hazardous constituents above the UTS.

 /. 7s There Treatment Capacity for the
 Proposed Wastes?

 1. What Is a Capacity Determination?
   EPA must determine whether
 adequate alternative treatment capacity
 exists nationally to manage the wastes
 subject to LDR treatment standards.
 RCRA section 3004 (h) (2). Thus, LDRs
 are effective when the new listings are
 effective as well (typically 6 months
 after the new listings are published in
 the Federal Register), unless EPA grants
 a national capacity variance from the
 otherwise-applicable date and
 establishes a different date (not to
 exceed two years beyond the statutory
 deadline) based on "*  *  * the earliest
 date on which adequate alternative
 treatment, recovery, or disposal capacity
 which protects human health and the
 environment will be available" (RCRA
 section 3004 (h) (2), 42 U.S.C.
 6924 (h) (2)).
  Our capacity analysis methodology
 focuses on the amount of waste
 currently disposed on the land, which
will require alternative or additional
treatment as a result of the LDRs. The
quantity of wastes that is not disposed  .

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                 Federal Register/Vol. 64, No.  164/Wednesday, August 25, 1999/Proposed Rules
                                                                       46523
  on the land, such as discharges
  regulated under NPDES, discharges to a
  POTW, or treatment in a RCRA-exempt
  tank, is not included in the quantities
  requiring additional treatment as a
  result of the LDRs. Also, land-disposed
  wastes that do not require alternative or
  additional treatment are excluded from
  the required capacity estimates (i.e.,
  those that currently are  treated to meet
  the LDR treatment standards). Land-
  disposed wastes requiring alternative or
  additional treatment or recovery
  capacity that is available on site or
  within the same company also are
  excluded from the required commercial
  capacity estimates. The resulting
  estimates of required commercial
  capacity then are compared to estimates
  of available commercial capacity. If
  adequate commercial capacity exists,
  the waste is restricted from further land
  disposal. If protective alternative
  capacity does not exist, EPA has the
  authority to grant a national capacity
  variance.
   In making the estimates described
  above, the volume of waste requiring
  treatment depends on the current waste
  management practices employed by the
 waste generators before this proposed
 regulation is promulgated and becomes
 effective. Data on waste management
 practices for these wastes were collected
 during the development  of this
 proposed rule. However, we realize that
 as the regulatory process proceeds,
 generators of these wastes may decide to
 minimize or recycle their wastes'or
 otherwise alter their management
 practices. Thus, we will monitor
 changes and update data on current
 management practices as these changes
 will affect the volume of wastes
 ultimately requiring commercial
 treatment or recovery capacity.
   The commercial hazardous waste
 treatment industry can change rapidly.
 For example, national commercial
 treatment capacity changes as new
 facilities come on line or old facilities
 go off line, and as new units and new
 technologies are added at existing
 facilities. The available capacity at
 commercial facilities also changes as
 facilities change their commercial status
 (e.g., changing from a fully commercial
 to a limited commercial or "captive"—
 company owned—facility). Thusi EPA
 also continues to update and monitor
 changes in available commercial
 treatment capacity.
  We request data on the  annual
 generation volumes and characteristics
 of wastes affected by this  proposed rule,
 including proposed hazardous wastes
 K173. K174, and K175 in wastewater
and nonwastewater forms, soil or debris
contaminated with these wastes,
  residuals generated from the treatment
  or recycling of these wastes, and the
  current and planned management
  practices for the wastes, waste mixtures,
  and treatment residuals.
    We also request data on the current
  treatment or recovery capacity capable
  of treating these wastes, facility and unit
  permit status related to treatment,of the
  proposed wastes and any plans that
  facilities may have to expand or reduce
  existing capacity, or construct new
  capacity.  Of particular interest to  us are
  waste characteristics,  such as pH, total
  organic carbon content, constituent
  concentrations, and physical forms that
  may limit the availability of certain
  treatment technologies. Also of interest
  are any analytical difficulties associated
  with identifying and monitoring the
  regulated constituents in these wastes.
 2. What are the Capacity Analysis
 Results?
   This preamble only provides a brief
 summary of the capacity analysis
 performed to support this proposed
 regulation. For additional and more
 detailed information, please refer to the
 "Background Document for Capacity
 Analysis for Land Disposal Restrictions:
 Newly Identified Chlorinated Aliphatics
 Process Wastes (Proposed Rule), July
 1999."
   For this capacity analysis, we
 examined data on waste characteristics
 and management practices gathered for
 the purpose of the chlorinated aliphatics
 hazardous waste listing determination.
 The source for these data is primarily
 the 1992 RCRA Section 3007 survey and
 the follow-up survey specific to these
 wastes conducted in 1997 (see the
 docket for this proposed regulation for
 more information on these survey
 instruments).
   The available data sources indicate
 that proposed K173 wastes are
 predominantly wastewaters, but may
 exhibit total suspended solids content
 greater than 1  percent, such that they
 would be classified as nonwastewaters
 with respect to the LDR requirements
 (40 CFR 268.2). EPA has found that
 most facilities generating proposed
 K173 manage these wastes in tank-based
 systems prior to a permitted discharge
 to a surface water or POTW. The non-
 CBI portions of the Section 3007 survey
 responses, as well as other publicly
 available information, indicate that
 certain facilities manage proposed K173
 using underground injection with
 existing approved no-migration
 determinations. Proposed K173
 managed by land disposal units may
 require alternative treatment if onsite
 management to meet the LDR standards
or alternative onsite management is not
  available. EPA expects that sufficient
  offsite treatment capacity is available to
  manage proposed K173 generated by
  these facilities. Specifically, EPA
  estimates that approximately 37 million
  tons per year of offsite wastewater
  treatment capacity are available, which
  is well above the quantity of proposed
  K173 generated by these facilities.
  Therefore, sufficient commercial
  capacity exists to manage proposed
  K173 from these facilities should the
  need for treatment of proposed K173
  wastes arise.
   As discussed in this section earlier,
  the LDR treatment standards become
  effective essentially at the same time a
  listing does  unless EPA grants a national
  capacity variance because of a lack of
  available treatment capacity (see RCRA
  section 3004(h) (2)). Also, RCRA allows
  generators to apply for an extension to
  the LDR effective date on a case-by-case
  basis for specific wastes generated at a
  specific facility for which there is not
  adequate capacity (RCRA section
  3004(h)(3}).  For those facilities
  managing proposed K173 wastes, they
  may choose  to meet treatment standards
  by onsite or  offsite treatment, submit a
  modified no-migration petition to
  include newly listed wastes if
  necessary, or transport their wastes to a
  commercial  Class I hazardous disposal
 well facility.
   Based on EPA's information, the
 facilities managing proposed K173
 wastes by underground injection have
 existing approved no-migration
 determinations. If an injection well has
 received a no-migration determination,
 it can inject a newly prohibited waste if
 the waste is similar to wastes included
 in the initial  no-migration petition (63
 FR 28626, May 26, 1998). EPA has
 information showing that the facilities
 already manage these newly-proposed
 K173 wastes  in their underground
 injection wells. Further, EPA's sampling
 and analysis  results for wastewater from
 one of the facilities shows that none of
 the constituents being proposed for
 inclusion in 40 CFR 268.40 for proposed
 K173 (i.e., numerical treatment
 standards) were present at
 concentrations greater than the
 proposed numerical treatment
 standards. This suggests that for this
 facility, the newly-proposed treatment
 standards for proposed K173 might
 already be met.
  Based on the available data presented
 above, EPA is not proposing a national
 capacity variance for surface-disposed
 or underground-injected proposed K173
wastes. However, EPA recognizes that
there are uncertainties in the available
data such that a facility may require
extra time (beyond the effective date) to

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Federal Register/Vol.  64, No. 164/Wednesday, August 25,  1999/Proposed Rules
 comply with the new listing and land
 disposal restrictions requirements, if
 finalized. For example, EPA realizes
 that proposed K173 can be variable in
 composition and not always exhibit
 concentrations below the proposed
 numerical treatment standards. Also,
 any facility with an approved no-
 migration determination without the
 waste already incorporated in the
 determination may need to submit a
 modified petition (40 CFR Part 148.20
 (f)). Potentially, the modification
 process for the existing no-migration
 petition, as well as the permit
 modification itself, may be time-
 consuming. There are potential
 logistical difficulties associated with
 accessing available treatment capacity
 for wastewater, as well. For example, if
 a facility generates high volumes of
 proposed K173 and cannot manage the
 waste onsite in a manner compliant
 with the LDR standards, they may  need
 to make considerable logistical
 adjustments  such as repiping, retooling,
 and development of transportation
 networks at the plant in order to ship
 the wastewater offsite for treatment or
 disposal. Additionally, although
 commercial treatment or disposal
 capacity is available, the logistics of
 transporting  high volumes of
 wastewater may be problematic,
 particularly if existing piping, onsite
 storage, or loading are not in place.
 Should these difficulties arise such that
 both onsite and offsite treatment and
 disposal are not available for facilities
 currently using underground injection,
 EPA will consider all available data and
 information provided during the public
 comment period and revise its capacity
 analysisiaccordingly in making the final
 capacity determination.
  For K174 wastes, the available data
 sources indicate that there is no
 quantity of the wastewater form of K174
 that will require alternative commercial
 treatment. There is adequate wastewater
 treatment capacity available should the
 need for treatment of the wastewater
 form of K174 arise. From the available
 data sources, required alternative
 treatment capacity for K174
 nonwastewater may be as low as 1,900
 tons per year if most generators meet the
 proposed requirements for contingent
 management  listing. If the generators do
 not manage K174 nonwastewater
 according to contingent management for
 the listing designation, the waste
 generated must meet LDR standards
 before land disposal, and the total
 quantity requiring treatment may be up
 to 106,000 tons per year. As described
 in the BDAT section above, we are
proposing that numerical treatment
                        standards be applied to K174
                        nonwastewaters. These standards were
                        derived by estimating the concentration
                        level following use of combustion
                        technologies. We estimate that the
                        commercially available sludge and solid
                        combustion capacity is at least 300,000
                        tons per year and therefore sufficient to
                        treat the proposed K174 hazardous
                        waste that would require treatment.
                        Therefore, EPA is proposing not to grant
                        a capacity variance for K174
                        nonwastewaters or wastewaters.
                         For wastes proposed to be listed as
                        K175, the available data sources
                        indicate that there is no quantity of the
                        wastewater form of proposed K175 that
                        will require alternative commercial
                        treatment. There is adequate wastewater
                        treatment capacity available should the
                        need for treatment of the wastewater
                        form of K175 arise. For nonwastewater
                        form of proposed K175, EPA estimates
                        that up to 130 tons per year may require
                        alternative commercial treatment. As
                        described in the BDAT section above,
                        two options are proposed as the
                        treatment standard. In one option, the
                        treatment standard was proposed as a
                        technology standard (RMERC), with
                        residues meeting a concentration level.
                        We have identified at least one facility
                        that operates commercially and that
                        potentially can be used for the treatment
                        of wastes proposed to be listed as K175;
                        there are other treaters which conduct
                        RMERC and the details are discussed in
                        the Capacity Analysis Background
                        Document. We recognize that treatment
                        residuals from these wastes may require
                        additional treatment capacity (e.g.,
                       stabilization of the ash following
                        combustion of the wastes) to  achieve the
                       UTS for any metal constituents that may
                       be present in the residuals. We estimate
                       that there is several million tons per
                       year of commercial stabilization
                       capacity available. In the second option
                       for nonwastewater form of proposed
                       K175 described in the BDAT section
                       above, the treatment standard would be
                       a numerical standard followed by
                       certain landfill restrictions. EPA expects
                       that commercial treaters can customize
                       their treatment process to immobilize
                       the waste, attain a pH of less than 6.0,
                       and meet the treatment standard.
                       Therefore, sufficient commercial
                       treatment capacity exists for this
                       proposed K175 hazardous waste. EPA is
                       proposing to not grant a national
                       capacity variance from LDR treatment
                       standards for nonwastewater or
                       wastewater forms of proposed K175.
                         Also, the ultimate volumes of wastes
                       estimated to require alternative or
                       additional commercial treatment may
                       change if the final listing determinations
 change; should this occur, we will
 revise the capacity analysis accordingly.
   For soil and debris contaminated with
 these wastes, EPA believes that the vast
 majority of contaminated soil and debris
 contaminated with these wastes will be
 managed on site and therefore will not
 require substantial commercial
 treatment capacity. Therefore, we are
 not proposing to grant a national
 capacity variance for hazardous soil and
 debris contaminated with the newly
 listed wastes covered under this
 proposal. Based on the 1992 RCRA 3007
 Survey questionnaire responses  and
 1997 updated responses, there are no
 data showing mixed radioactive wastes
 associated with the proposed listings.
 We are .not proposing to grant a national
 capacity variance for mixed radioactive
 wastes (i.e., radioactive wastes mixed
 with proposed K173, K174, or K175)  or
 soil and debris contaminated with these
 mixed radioactive wastes. As discussed
 in this section earlier, EPA also is not
 proposing to grant a national capacity
 variance for proposed K173, K174, or
 K175 wastes being surface-disposed or
 underground injected.
   EPA requests comments on current
 and future management practices and
 the volumes managed for these wastes.
 Also, we request comments on other
 commercially-available thermal and
 non-thermal treatment or recovery
 capacity that would achieve proposed
 LDR treatment standards for these
 wastes and on chemical and physical
 constraints of treatment technologies  for
 the wastes. Specifically, EPA requests
 comments on its proposal to not grant
 a capacity variance for proposed K173
 waste. EPA solicits comments on
 physical and chemical characteristics of
 proposed K173 wastes, any treatment
 problems before disposing of proposed
 K173,  the time and necessary
 procedures required for permit
 modifications for proposed K173
 generators or commercial treatment or
 disposal facilities, required changes for
 operating practices, and any specific
 difficulties in making treatment capacity
 unavailable that would warrant a
 variance. For nonwastewater form of
 proposed K175, we solicit any
 information regarding the availability of
 RMERC for treating the wastes, and
 regarding chemical and physical
 constraints to meet numerical standards
 and pH restriction for this waste.

 IV. Compliance Dates

 A. Notification
  Under RCRA Section 3010 any  person
generating, transporting, or managing a
hazardous waste must notify EPA (or an
authorized State) of its activities.

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                Federal Register/Vol.  64,  No. 164/Wednesday, August 25, 1999/Proposed Rules
                                                                      46525
  Section 3010 (a) allows EPA to waive,
  under certain circumstances, the
  notification requirements under Section
  3010 of RCRA. EPA is proposing to
  waive the notification requirement as
  unnecessary for persons already
  identified within the hazardous waste
  management universe (i.e., persons who
  have an EPA identification number
  under 40 CFR 262.12). EPA is not
  proposing to waive the notification
  requirement for waste handlers who
  have neither notified the Agency that
  they may manage hazardous wastes nor
  received an  EPA identification number.
  Such individuals will have to provide
  notification  under Section 3010. Any
  person who  generates, transports, treats,
  stores, or disposes of these wastes and
  has not previously  received an EPA
  identification number, must do so
  within 90 days of the effective date of
  the final rule.
  B. Interim Status and Permitted
  Facilities
   Today's proposed rule is being
  proposed under the authorities granted
  to EPA under HSWA. Because HSWA
  requirements are applicable in
  authorized States at the same time as in
 unauthorized States, EPA will regulate
 the newly identified wastes listed under
 HSWA until  States  are authorized to
 regulate these wastes. Thus, once this
 regulation becomes effective as a final
 rule, EPA will apply Federal regulations
 to these wastes and to their management
 in both authorized and unauthorized
 States.
 VII. State Authority
 A. Applicability of Rule in Authorized
 States
   Under Section 3006 of RCRA, EPA
 may authorize qualified States to
 administer and enforce the RCRA
 program within the  State. (See 40 CFR
 Part 271 for the standards and
 requirements for authorization.)
 Following authorization, EPA retains
 enforcement authority under Sections
 3007, 3008, 3013, and 7003 of RCRA,
 although authorized States have primary
 enforcement responsibility.
   Before the Hazardous and Solid Waste
 Amendments of 1984 (HSWA) amended
 RCRA, a State with final authorization
 administered  its hazardous waste
 program entirely in lieu of the Federal
 program in that State. The Federal
 requirements  no longer applied in the
 authorized State, and EPA could not
 issue permits  for any facilities located in
 the State with permitting authorization.
When new, more stringent Federal
requirements  were promulgated or
enacted, the State was obligated to enact
  equivalent authority within specified
  time-frames. New Federal requirements
  did not take effect in an authorized State
  until the State adopted the requirements
  as State  law.
    By contrast, under Section 3006 (g) of
  RCRA, 42 U.S.C. 6926(g), new
  requirements and prohibitions imposed
  by the HSWA (including the hazardous
  waste listings proposed in this notice)
  take effect in authorized States at the
  same time that they take effect in non-
  authorized States. EPA is directed to
  implement those requirements and
  prohibitions in authorized States,
  including the issuance of permits, until
  the State is granted authorization to do
  so. While States must still adopt HSWA-
  related provisions as State law to retain
  final authorization, the Federal HSWA
  requirements apply in authorized States
  until the States revise their program and
  receive authorization for the revisions.

  B. Effect on State Authorizations

   Because this proposal (with the
 exception of the actions proposed under
 CERCLA authority) will be promulgated
 pursuant to the HSWA, a State
 submitting a program modification is
 able to apply to receive either interim or
 final authorization under Section
 3006(g)(2) or 3006(b), respectively, on
 the basis  of requirements that are
 substantially equivalent or equivalent to
 EPA's requirements. The procedures
 and schedule for State program
 modifications under Section 3006 (b) are
 described in 40 CFR 271.21. It should be
 noted that all HSWA interim
 authorizations are currently scheduled
 to expire  on January 1, 2003 (see 57 FR
 60129, February 18, 1992).
  Section 271.2 l(e) (2) of EPA's State
 authorization regulations (40 CFR Part
 271) requires that states with final
 authorization modify their programs to
 reflect Federal program changes and
 submit the modifications to EPA for
 approval.  Once EPA approves the
 modification, the State requirements
 become RCRA subtitle C requirements.
 Because this rule would be promulgated
 pursuant to HSWA, if the proposal is
 adopted as a final rule, Table 1 at 40
 CFR 271.1 will be amended accordingly.
If finalized, EPA will implement this
rule in all States, including authorized
States, until the States modify their
authorized programs to reflect this rule.
  VIII. Designation of Chlorinated
  Aliphatic Wastes (Proposed K173, K174
  and K175) Under the Comprehensive
  Environmental Response,
  Compensation, and Liability Act
  (CERCLA)
  A. What Is the Relationship Between
  RCRA and CERCLA?
    CERCLA defines the term "hazardous
  substance" to include RCRA hazardous
  wastes. When EPA adds a hazardous
  waste under RCRA, the Agency also will
  add the waste to its list of CERCLA
  hazardous substances. EPA establishes a
  reportable quantity or RQ for each
  CERCLA hazardous substance. EPA
  provides a list of the CERCLA hazardous
  substances along with their RQs in
  Table 302.4  at 40 CFR 302.4. If you are
  the person in charge of a vessel or
  facility that releases a CERCLA
  hazardous substance in an amount that
  equals or exceeds its RQ, then you must
  report that release to the National
  Response Center (NRC). You also may
  have to notify State and local
  authorities.
 B. Is EPA Proposing To Add Chlorinated
 Aliphatic Wastes to CERCLA?
   Yes. Today, EPA is proposing to add
 chlorinated aliphatic wastes (Proposed
 K173, K174 and K175) to the list of
 CERCLA hazardous substances. As
 discussed below, EPA also proposes to
 adjust the RQs for these wastes.

 C. How Does EPA Determine Reportable
 Quantities?
   Under CERCLA, all new hazardous
 substances automatically have a
 statutory one-pound RQ. EPA adjusts
 the RQ of a newly added hazardous
 substance based on an evaluation of its
 intrinsic physical, chemical, and toxic
 properties. These intrinsic properties—
 called "primary criteria"—are aquatic
 toxicity, mammalian toxicity (oral,
 dermal, and inhalation), ignitability,
 reactivity, chronic toxicity, and
 potential carcinogenicity. EPA evaluates
 the data for a hazardous substance for
 each primary criterion. To adjust the
 RQs, EPA ranks each criterion on a scale
 that corresponds to an RQ value of 1, 10,
 100, 1,000, or 5,000 pounds.  For each
 criterion, EPA establishes a tentative
 RQ. A hazardous substance may receive
 several tentative RQ values based on its
 particular intrinsic properties. The
 lowest of the tentative RQs becomes the
 "primary criteria RQ"  for that
substance.
  After the primary criteria RQs are
assigned, EPA further evaluates
substances for their susceptibility to
certain degradative processes. These are '
secondary adjustment criteria. The

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Federal Register/Vol. 64,  No. 164/Wednesday,  August 25, 1999/Proposed Rules
natural degradative processes are
blodegradation, hydrolysis, and
photolysis (BHP). If a hazardous
substance, when released into the
environment, degrades rapidly to a less
hazardous form by one or more of the
BHP processes, EPA generally raises its
RQ (as determined by the primary RQ
adjustment criteria) by one level.
Conversely, if a hazardous substance
degrades to a more hazardous product
after its release, EPA assigns an RQ to
the original substance equal to the RQ
for the more hazardous substance.
  The standard methodology used to
adjust the RQs for RCRA hazardous
waste streams differs from the
methodology applied to individual
hazardous substances. The procedure
for assigning RQs to RCRA waste
streams is based on the results of an
analysis of the hazardous constituents of
the waste streams. The constituents of
each RCRA hazardous waste stream are
identified in 40 CFR Part 261, Appendix
VII. EPA first determines an RQ for each
hazardous constituent within the waste
stream using the methodology described
above. The lowest RQ value of these
constituents becomes the adjusted RQ
for the waste stream. When there are
hazardous constituents of a RCRA waste
stream that are not CERCLA hazardous
substances, the Agency develops an RQ,
                       called a "reference RQ," for these
                       constituents in order to assign an
                       appropriate RQ to the waste stream (see
                       48 FR 23565, May 25, 1983). In other
                       words, the Agency derives the RQ for
                       waste streams based on the lowest RQ
                       of all of the hazardous constituents,
                       regardless of whether they are CERCLA
                       hazardous substances.
                       D. When Do I Need To Report a Release
                       of Proposed Kl 73, Kl 74 or Kl 75 Under
                       CERCLA?
                         Today, EPA is proposing to adjust
                       statutory RQs for the proposed K173,
                       K174 or K175 waste streams to one
                       pound based on their hazardous
                       constituents. EPA is proposing to adjust
                       the RQ at one pound for the proposed
                       K173 and K174 waste streams based on
                       their hazardous constituents,
                       chlorinated dibenzo-p-dioxins (CDDs)
                       and chlorinated dibenzofurans (CDFs).
                       EPA is proposing to adjust the RQ at one
                       pound for the proposed K175 waste
                       stream based on its hazardous
                       constituent, mercury. However, in
                       determining when to report a release of
                       proposed K173, K174 or K175, EPA is
                       proposing to allow you to apply the
                       mixture rule, codified in 40 CFR 302.6,
                       using the maximum observed
                       concentrations of the hazardous
                       constituents within the respective waste
                       streams.
  The mixture rule provides that
"discharges of mixtures and solutions
are subject to RQ regulations only where
a component hazardous substance of the
mixture or solution is discharged in a
quantity equal to or greater than its RQ"
(44 FR 50767, Augusr29, 1979).
Therefore, if the concentration of a
hazardous constituent is known, the
amount of release needed to reach its
RQ can be calculated. By using the
maximum observed concentration that
EPA is proposing today, you may apply
the mixture rule, even if you don't know
the concentration of constituents
released. That is, if you are the person
in charge, you must immediately report
the release as soon as you know that you
have released proposed K173,  K174 or
K175 in an amount that will reach the
RQ for the waste stream. This approach
is reasonable and conservative because
the sampling data presented in the
Listing Background Document
accurately identify the maximum
observed concentrations of the
hazardous constituents in the
chlorinated aliphatics waste streams.
Table VIII-1 below identifies the
hazardous constituents for each waste
stream, their maximum observed
concentrations in parts per million
(ppm), and their constituents' RQs or
reference RQs.
 TABLE VIII-1.—MAXIMUM OBSERVED CONCENTRATION AND CORRESPONDING RQ FOR HAZARDOUS CONSTITUENTS THAT
                            ARE BASIS FOR LISTING PROPOSED K173, K174, AND K175
Waste
K173

















K174











Constituent
237 8-TCDD " 	
1237 8-PeCDD 	
1 2 3,4,7,8-HxCDD 	
12367 8-HxCDD 	
12378 9-HxCDD 	 	 	
123467 8-HpCDD 	
OCOD 	
2378-TCDF 	
1237 8-PeCDF 	
2347 8-PeCDF 	
12347 8-HxCDF 	
12367 8-HxCDF 	
1,237,89-HxCDF 	
23467 8-HxCDF 	
1,2 3 4 6 7 8-HpCDF 	
1 2,3 4 7 8 9-HpCDF 	
OCDF 	
Chloroform 	
237 8-TCDD 	
1 2 37 8-PeCDD 	
1234 7,8-HxCDD 	
11 2367 8-HxCDD 	 .' 	
1 ,2 3 7,8 9-HxCDD 	
1 23467 8-HpCDD 	
OCDD 	
237 8-TCDF 	
1 2378-PeCDF 	
2347 8-PeCDF 	
12347 8-HxCDF 	
1.2.3.6.7.8-HxCDF 	 - 	 : 	
Max.
Concentration
(ppm (mg/kg))
.000000017
.00000015
.00000012
.00000091
.00000092
.000044
.00022
.00000045
.0000012
.0000015
.000042
.000045
.000014
.000027
.0013
.00017
.006
.7
.000039
.0000108
.000024
.000083
.000062
.00123
.0129
.000145
.000077V
.000127
.001425
.000281
RQ (!b)
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
10
1
1
1
1
1
1
1
1
1
1
1
1

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                Federal Register/Vol.  64,  No. 164/Wednesday,  August 25, 1999/Proposed Rules
                                                                      46527
  TABLE Vlll-1.—MAXIMUM OBSERVED  CONCENTRATION AND CORRESPONDING RQ FOR HAZARDOUS CONSTITUENTS THAT
                        ARE BASIS FOR LISTING PROPOSED K173, K174, AND K175—Continued
Waste





K175

Constituent
1 ,2,3,7,8,9-HxCDF 	
2,3,4,6,7,8-HxCDF 	
1,2,3,4,6,7,8-HpCDF 	
1,2,3,4,7,8,9-HpCDF 	
OCDF 	
Mercury 	

Max.
Concentration
(ppm (mg/kg))
~00014
nnnfi/iR
nony
on^
919
Q9nn

RQ (Ib)







   For example, if proposed K173 is
 released from your facility and you do
 not know the actual concentrations of
 its constituents, you may assume that
 the concentrations are those identified
 in Table VIII-1. Thus, applying the
 mixture rule to the assumed maximum
 concentrations indicated in the table,
 you would have to release  1,408,450
 pounds to reach the RQ for this waste
 (based on the maximum observed
 concentration of chloroform). If
 proposed K174 waste is released from
 your facility and you do not know the
 actual concentrations of its constituents,
 you may apply the mixture rule to the
 assumed maximum concentrations
 indicated in the table. You would have
 to release 4,716,981 pounds of proposed
 K174 to reach the RQ for this waste
 (based on the maximum observed
 concentration of OCDF). If proposed
 K175 is released from your facility and
 you do not know the actual
 concentration of mercury, you may
 assume that the concentration is 9200
 ppm. Applying the mixture rule, you
 would have to release 108.7 pounds of
 this waste to reach the RQ.

 E. What if I Know the Concentration of
 the Constituents in My Waste?

   If you know the concentration levels
 of all the hazardous constituents in a
 particular chlorinated aliphatic waste,
 you may apply the mixture rule (see 40
 CFR 302.6(b)) to the actual
 concentrations. You would need to
 report a release of either waste when an
 RQ or more of any of their respective
 hazardous constituents is released.
 F. How Did EPA Determine the RQs for
 Proposed Kl 73, Kl 74 and Kl 75 and
 Their Hazardous Constituents?

  The hazardous constituents identified
 as the basis for listing the proposed
 K173 and K174  waste streams include
 chlorinated dibenzo-p-dioxins (CDDs)
 and chlorinated dibenzofurans (CDFs).
 Previously, EPA had established an
adjusted RQ of one pound for 2,3,7,8-
TCDD (see 54 FR 33426). EPA has not
established adjusted RQs for the other
  CDD and CDF congeners. However, EPA
  recognizes that a number of these
  congeners exhibit dioxin-like toxicity
  and has established "reference RQs" of
  one pound for these congeners to
  support the development of the adjusted
  RQs for the proposed K173 and K174
  waste streams.
   The adjusted RQ for 2,3,7,8-TCDD
  was established as one pound based on
  potential carcinogenicity, considering
  the weight of evidence that this
 substance is carcinogenic, and
 considering its estimated carcinogenic
 potency. To establish reference RQs for
 the other CDD and CDF congeners in the
 waste stream, EPA applied the toxicity
 equivalency factors (TEFs) established
 for dioxin-like compounds to the
 potency factor used as the basis for the
 adjusted RQ for 2,3,7,8-TCDD. Of the
 210 CDD and CDF congeners, only those
 with chlorine substitutions in, at least,
 the  2, 3, 7, and 8 positions (a total of 17
 CDD and CDF congeners) are considered
 to have dioxin-like toxicity. Applying
 the TEFs established for these 17
 congeners to the potency factor
 established for 2,3,7,8-TCDD indicates
 that all of the congeners fit into RQ
 Potency Group 1 with a corresponding
 reference RQ of one pound.58 Therefore,
 because each of the hazardous
 constituents has an RQ or reference RQ
 of one pound, EPA is proposing to
 establish an adjusted RQ of one pound
 for the proposed K173 and K174 waste
 streams.
  The hazardous constituent identified
 as the basis for proposing to list the
 K175 waste stream is mercury.
 Previously, EPA had established an
 adjusted RQ of one pound for mercury
 (see  50 FR 13456, April 4, 1985).
 Because the hazardous constituent used
 as the basis for listing the K175 waste
 stream has an RQ of one pound, EPA is
  58 For an explanation of how potency factors are
calculated and potency groups and RQs are
established, see the Technical Background
Document to Support Rulemaking Pursuant to
CERCLA Section 102, Volume 3, July 27. 1989. This
document can be viewed by calling the EPA
Superfund Docket Center, 703-603-8917, and
requesting document number 102 RQ 273C:
  proposing to establish an adjusted RQ of
  one pound for this waste.

  G. How Do I Report a Release?
   To report a release of proposed K173,
  K174 or K175 (or any other CERCLA
  hazardous substance) that equals or
  exceeds its RQ, you must immediately
  notify the National Response Center
  (NRC) as soon as you have knowledge
  of that release. The toll-free telephone
  number of the NRC is 1-800-424-8802;
  in the Washington, DC, metropolitan
  area, the  number is (202) 267-2675.
   You also  may have to notify State and
  local authorities. The Emergency
  Planning and Community Right-to-
  Know Act (EPCRA) requires that owners
  and operators of certain facilities report
  releases of CERCLA hazardous
 substances and EPCRA  extremely
 hazardous substances (see list in 40 CFR
 Part 355,  Appendix A) to State and local
 authorities.  After the release of an RQ or
 more of any of those substances, you
 must report immediately to the
 community emergency coordinator of
 the local emergency planning committee
 for any area likely to be affected by the
 release, and to the State emergency
 response commission of any State likely
 to be affected by the release.

 H. What Is the Statutory Authority for
 This Program?

  Section 101(14) of CERCLA defines
 the term hazardous substance by
 referring to substances listed under
 several other environmental statutes, as
 well as those substances that EPA
 designates as hazardous under CERCLA
 Section 102(a). In particular, CERCLA
 Section 101 (14) (C) defines the term
 hazardous substance to include "any
 hazardous waste having  the
 characteristics identified under or listed
 pursuant to Section 3001 of the Solid
 Waste Disposal Act." CERCLA Section
 102 (a) gives EPA authority to establish
 RQs for CERCLA hazardous substances.
 CERCLA Section 103 (a) requires any
 person in charge of a vessel or facility
that releases  a CERCLA hazardous
substance  in an amount equal to or

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Federal Register/Vol.  64,  No.  164/Wednesday, August 25, 1999/Proposed Rules
 greater than its RQ to report the release
 Immediately to the federal government.
 EPCRA Section 304 requires owners or
 operators of certain facilities to report
 releases of CERCLA hazardous
 substances and EPCRA extremely
 hazardous substances to State and local
 authorities.
 /, How Can I Influence EPA's Thinking
 on Regulating Proposed Kl 73, Kl 74 and
 Kl 75 Under CERCLA?
   In developing this proposal, EPA tried
 to address the concerns of all our
 stakeholders. Your comments will help
 us to improve this proposal. We invite
 you to provide your views on this
 proposal and how it may affect you. We
 also are interested in receiving any
 comments that you have on the
 information provided in Table VIII-1,
 including the hazardous constituents
 identified for proposed K173. K174 and
 K175 and the maximum observed
 concentrations for each constituent.
 IX. Administrative Assessments
 A, Executive Order 12866
   Under Executive Order 12866
 (September 30. 1993), EPA must
 determine whether a regulatory action is
 "significant" and, therefore, subject to
 OMB review and the other provisions of
 the Executive Order. A significant
 regulatory action is defined by
 Executive Order 12866 as one that may:
   (1) Have an annual effect on the economy
 of SI00 million or more or adversely affect
 in a material way the economy, a sector of
 the economy, productivity, competition, jobs,
 the environment, public health or safety, or
 State, local, or tribal governments or
 communities:
  (2) Create a serious inconsistency or
 Otherwise interfere with an action taken or
 planned by another agency:
  (3) Materially alter the budgetary impact of
 entitlements, grants, user fees, or loan
 programs or rights and obligations or
 recipients thereof: or
  (4) Raise novel legal or policy issues
 arising out of legal mandates, the President's
 priorities, or the principles set forth in
 Executive Order 12866.
 Pursuant to the terms of Executive
 Order 12866, EPA has determined that
 this rule is a "significant regulatory
 action" because of point four (4) above:
 The rule raises two novel legal or  policy
 issues arising out of legal mandates, the
 President's priorities, or the principles
 set forth in this Executive Order.
 Today's proposed rule, which includes
 proposed alternative listing approaches
 for two wastestreams deviates from the
 Agency's standard or historic listing
 approach in the following two ways:
  • Targeted wastestream listing:
Historically, the Agency's listing program
                        captured entire quantities of targeted
                        wastestream posing unacceptable risks to
                        human health and the environment. Today's
                        proposed listing approach for two
                        wastestreams (i.e., EDC/VCM wastewater
                        treatment sludges and one alternative option
                        for VCM-A wastewater treatment sludges)
                        proposes listing as hazardous only those
                        quantities of the waste that are managed in
                        a manner that reflects unacceptable risks.
                          •  Wastewater treatment units:In addition,
                        today's action proposes to change a long-
                        standing Agency policy of exempting from
                        RCRA regulation the management of
                        hazardous wastes in wastewater treatment
                        units regulated under § 402 or § 307 (b) of the
                        Clean Water Act. To address the risks
                        associated with the wastewaters proposed to
                        be listed as hazardous under today's action,
                        the Agency believes that it is necessary to
                        regulate these management units when used
                        to manage chlorinate aliphatic wastewaters,
                        to ensure against hazardous air emissions
                        from this wastestream. (In section III.E.l.a.vi.
                        of today's preamble, EPA is requesting
                        comment on this approach.)
                        Due to the Agency's decision to  propose
                        a deviation from our historical
                        hazardous waste listing approach and to
                        change our long-standing policy
                        regarding the  regulation of wastewater
                        treatment units, the Agency is deeming
                        today's action to  be "significant" and is
                        submitting these  proposed policy
                        changes to OMB for review. Changes
                        made to the Agency's proposed actions
                        in response to OMB suggestions or
                        recommendations are documented in
                        the public record.
                         Although today's proposed rule is not
                        "economically significant," the Agency
                        prepared an "Economic Background
                        Document" iia support of today's rule.
                        The Agency's  economic assessment
                        addresses, among other factors, industry
                        compliance costs, industry financial
                        impacts, and potential for small entity
                        impacts. A summary of findings from
                        our economic  assessment is presented
                        in Section IV.  The complete Economic
                       Background Document is available for
                       public review  from the RCRA docket,
                       according to instructions provided in
                       the introduction to this preamble.

                       B. Regulatory Flexibility Act
                         Pursuant to the 1980 Regulatory
                       Flexibility Act (RFA) (5 U.S.C. 601 et
                       seq., as amended by the Small Business
                       Regulatory Enforcement Fairness Act
                       (SBREFA) of 1996), whenever an agency
                       is required to publish a notice of
                       rulemaking for any proposed or final
                       rule, it must prepare and make available
                       for public comment, a regulatory
                       flexibility analysis that describes the
                       effect of the rule on small entities (i.e.,
                       small businesses, small organizations,
                       and small governmental jurisdictions).
                       However, regulatory flexibility analysis
                       is not required  if the head of an agency
  certifies that the rule will not have a
  "significant" economic impact on a
  substantial number of small entities.
   SBREFA amended the Regulatory
  Flexibility Act to require Federal
  agencies to provide a statement of the
  factual basis for certifying that a rule
  will not have a "significant" economic
  impact on a substantial number of small
  entities. The following discussion
  explains EPA's determination.     '
   EPA has examined this rule's
  potential effects on small entities as
  required by the RFA/SBREFA, and has
  determined  that this action will not
  have a significant economic impact on
  a substantial number of small entities.
 This is evidenced by the fact that only
 one of the potentially affected, parent
 companies determined to be producers
 of chlorinated aliphatic products in the
 U.S., may be classified  as a  "small
 business," according to the  U.S. Small
 Business Administration's employee
 size standards (i.e., less than or equal to
  1,000 employees) and according to  that
 company's primary Standard Industrial
 Classification (SIC) code (SIC 2869).
   I hereby certify that this rule will not
 have a significant economic impact on
 a substantial number of small entities.
 This rule, therefore, does not require a
 regulatory flexibility analysis.
 C. Paperwork Reduction Act
   The information collection
 requirements in this proposed rule have
 been submitted for approval to the
 Office of Management and Budget
 (OMB) under the Paperwork Reduction
 Act, 44 U.S.C. 3501 etseq. An
 Information Collection Request (ICR)
 document was prepared by EPA (ICR
 No. 1924.01) and a copy may be
 obtained from Sandy Farmer by mail at
 OP Regulatory Information Division;
 U.S. Environmental Protection Agency
 (2137); 401 M Street, S.W.; Washington,
 D.C. 20460, by E-mail at
 farmer.sandy@epamail.epa.gov, or by
 calling (202)  260-2740.  A copy also may
 be downloaded off the Internet at http:/
 /www.epa.gov/icr.
  This proposed rule includes new
 information collection requirements
 subject to OMB review under the
 Paperwork Reduction Act of 1995, 44
 U.S.C. 3501 etseq. In addition to
 complying with the existing subtitle C
 recordkeeping and reporting
 requirements for the newly listed waste
 streams, EPA is proposing that facilities
 generating chlorinated aliphatic
 wastewaters comply with testing
 requirements. In conjunction with
testing requirements, we are  proposing
that generators maintain documentation
of detailed standard operating
procedures for the sampling  arid

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                Federal  Register/Vol. 64, No. 164/Wednesday, August 25, 1999/Proposed Rules
                                                                      46529
  analysis protocols that were employed,
  sensitivity and bias of the measurement
  process, precision of the results, and the
  analytical results from testing events.
  These requirements are being proposed
  to ensure generators are complying with
  the proposed technical standards for
  controlling air emissions of dioxins
  from wastewater treatment tanks.
   EPA also is proposing that generators
  be able to document their compliance
  with the conditions provided for
  exclusion from the scope of the two
  conditional hazardous waste listings
  proposed in today's notice. This
  requirement is necessary to ensure that
  both EDC/VCM wastewater treatment
  sludges and VCM-A wastewater
  treatment sludges are managed in a
  manner that is safe for human health
  and the environment. In addition, EPA
  is requiring' disposal facilities that
  manage VCM-A wastewater treatment
  sludges to maintain records
  documenting that these sludges are co-
  disposed only with other wastes that
  have a pH level of 6.0 or lower. This
 requirement is necessary to ensure that
 the mercury contained in the waste does
 not leach from the waste after disposal.
   The Agency estimated the burden
 associated with complying with the
 requirements in this proposed rule.
 Included in the ICR are the burden
 estimates for the following requirements
 for industry respondents: reading the
 regulations; performing testing and
 waste analyses; keeping records of
 testing results; completing and
 submitting certifications; incorporating
 testing and waste analysis requirements
 into permits; keeping records
 documenting compliance with
 conditions for exclusion from hazardous
 waste listings; and keeping records
 documenting compliance with landfill
 waste disposal requirements for the
 disposal of VCM-A wastewater
 treatment sludges. Included also are the
 burden estimates for State respondents
 for applying for State authorization. The
 Agency determined that all of this
 information is necessary to ensure
 compliance with today's proposed rule.
  To the extent that this rule imposes
 any information collection requirements
 under existing RCRA regulations
 promulgated in previous rulemakings,
 those requirements have been approved
 by the Office of Management and
 Budget (OMB) under the Paperwork
 Reduction Act, 44 U.S.C. 3501 etseq.,
 and have been assigned OMB control
 numbers 2050-0009 (ICR No. 1573, Part
 B Permit Application, Permit
 Modifications, and Special Permits);
 2050-0120 (ICR No. 1571, General
Facility Hazardous Waste Standards);
2050-0028 (ICR No. 261, Notification of
  Hazardous Waste Activity); 2050-0034
  (ICR No. 262, RCRA Hazardous Waste
  Permit Application and Modification,
  Part A); 2050-0039 (ICR.N.O. 801,
  Requirements for Generators,
  Transporters, and Waste Management
  Facilities under the Hazardous Waste
  Manifest System); 2050-0035 (ICR No.
  820, Hazardous Waste Generator
  Standards); and 2050-0024 (ICR No.
  976, 1997 Hazardous Waste Report).
    EPA estimates that the projected
  annual hour burden for industry
  respondents will be 1,088 hours, and
  cost of $184,186. Total estimates over
  three years are 3,264 hours and
  $552,558.
    Burden means the total time, effort, or
  financial resources expended by persons
  to generate, maintain, retain, or disclose
  or provide information to or for a
  Federal agency. This includes the time
  needed to review instructions;  develop,
  acquire, install, and use technology and
  systems for the purposes of collecting,
  validating, and verifying information,
  processing and maintaining
  information, and disclosing and
  providing information; adjust the
  existing ways to comply with any
  previously applicable instructions and
  requirements; train personnel to be able
  to respond to a collection of
  information; search data sources;
  complete and review the collection of
  information; and transmit or otherwise
 disclose the information.
   An agency may not conduct or
 sponsor, and a person is not required to
 respond to a collection of information
 unless it displays a currently valid OMB
 control number. The OMB control
 numbers for EPA's regulations are listed
 in 40 CFR Part 9 and 48 CFR Chapter
 15.
   Comments are requested on the
 Agency's need for this information, the
 accuracy of the provided burden
 estimates, and any suggested methods
 for minimizing respondent burden,
 including through the use of automated
 collection techniques. Send comments
 on the ICR to the Director, OP
 Regulatory Information Division; U.S.
 Environmental Protection Agency
 (2137); 401 M Street, S.W.; Washington,
 D.C. 20460; and to the Office of
 Information and Regulatory Affairs,
 Office of Management and Budget, 725
 17th Street, N.W.; Washington, D.C.
 20503, marked "Attention: Desk Officer
 for EPA." Include the ICR number in
 any correspondence. Since OMB is
 required to make a decision concerning
 the ICR between 30 and 60 days after
August 25,  1999, a comment to OMB is
best assured of having its full effect if
OMB receives it by September 24, 1999.
The final'rule will respond to any OMB
  and public comments on the
  information collection requirements
  contained in this proposal.

  D. Unfunded Mandates Reform Act
    Title II of the Unfunded Mandates
  Reform Act of 1995 (UMRA), Pub. L.
  104-4, establishes requirements for
  Federal agencies to assess the effects of
  their regulatory actions on State, local,
  and tribal governments and the private
  sector. Under Section 202 of the UMRA,
  EPA generally must prepare a written
  statement, including a cost-benefit
  analysis, for proposed and final rules
  with "Federal mandates" that may
  result in expenditures by State, local,
  and tribal governments, in the aggregate,
  or by the private sector, of $100 million
  or more in any one year. Before
  promulgating an EPA rule for which a
  written statement is needed, Section 205
  of the UMRA generally requires EPA to
  identify and consider a reasonable
  number of regulatory alternatives and
  adopt the least costly, most cost-
  effective or least burdensome alternative
  that achieves the objectives of the rule.
  The provisions of Section 205 do not
  apply when they are inconsistent with
  applicable law. Moreover, Section 205
  allows EPA to adopt an alternative other
  than the least costly, most cost-effective
  or least burdensome alternative if the
 Administrator publishes with the final
 rule an explanation why that alternative
 was not adopted. Before EPA establishes
 any regulatory requirements that may
 significantly or uniquely affect small
 governments, including tribal
 governments, it must have developed
 under Section 203 of the UMRA a small
 government agency plan. The plan must
 provide for notifying potentially
 affected small governments, enabling
 officials of affected small governments
 to have meaningful and timely input in
 the development of EPA regulatory
 proposals with significant Federal
 intergovernmental mandates, and
 informing, educating, and advising
 small governments on compliance with
 the regulatory requirements.
  The Agency's analysis for compliance
 with the UMRA found that the proposed
 action imposes less than the $100
 million expenditure threshold on the
 private sector; thus, today's rule is not
 subject to the requirements of Sections
 202 and 205 of UMRA.

 E. Executive Order 12875: Enhancing
 the Intergovernmental Partnership
  Under Executive Order 12875; EPA
 may not issue a regulation that is not
 required by statute and that creates a
mandate upon a State, local or tribal
government, unless the Federal
government provides the funds

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 necessary to pay the direct compliance
 costs incurred by those governments, or
 EPA consults with those governments. If
 EPA complies by consulting, Executive
 Order 12875 requires EPA to provide to
 the Office of Management and Budget a
 description of the extent of EPA's prior
 consultation with representatives of
 affected State, local and tribal
 governments, the nature of their
 concerns, any written communications
 from the governments, and a statement
 supporting the need to issue the
 regulation. In addition. Executive Order
 12875 requires EPA to develop an
 effective process permitting elected
 officials and other representatives of
 State, local and tribal governments "to
 provide meaningful and timely input in
 the development of regulatory proposals
 containing significant unfunded
 mandates,"

 F. Executive Order 13084: Consultation
 and Coordination With Indian Tribal
 Governments

   Under Executive Order 13084, EPA
 may not issue a regulation that is not
 required by statute, that significantly or
 uniquely affects the communities of
 Indian tribal governments, and that
 imposes substantial direct compliance
 costs on those communities, unless the
 Federal government provides the funds
 necessary to pay the direct compliance
 costs incurred by the tribal
 governments, or EPA consults with
 those governments. If EPA complies by
 consulting. Executive Order 13084
 requires EPA to provide to the Office of
 Management and Budget, in a separately
 identified section of the preamble to the
 rule, a description of the extent of EPA's
 prior consultation with representatives
 of affected tribal governments, a
 summary of the nature of their concerns,
 and a statement supporting the need to
 issue the regulation. In addition,
 Executive Order 13084 requires EPA to
 develop an effective process permitting
 elected officials and other
 representatives of Indian tribal
 governments "to provide meaningful
 and timely input in the development of
 regulatory policies on matters that
 significantly or uniquely affect their
 communities."
  Today's rule does not significantly or
 uniquely affect the communities of
 Indian tribal governments. There is no
 impact to tribal governments as the
 result of the proposed action. In
 addition, this proposed rule is required
 by statute (HSWA). Accordingly, the
requirements of Section 3(b) of
Executive Order 13084 do not apply to
this rule.
                        G. Executive Order 13045: Protection of
                        Children From Environmental Health
                        Risks and Safety Risks
                          Executive Order 13045, "Protection of
                        Children from Environmental Health
                        Risks and Safety Risks" (62 FR 19885,
                        April 23, 1997), applies to any rule that:
                        (1) is determined to be "economically
                        significant" as defined under E.O.
                        12866, and (2) concerns an
                        environmental health or safety risk that
                        EPA has reason to believe may have a
                        disproportionate effect on children. If
                        the regulatory action meets both criteria,
                        the Agency must evaluate the
                        environmental health or safety effects of
                        the planned rule on children, and
                        explain why the planned regulation is
                        preferable to other potentially effective
                        and reasonably feasible alternatives
                        considered by the Agency. This
                        proposed rule is not subject to the
                        Executive Order because it is not
                        economically significant as defined in
                        E.O. 12866, and because the Agency
                        does not have reason to believe the
                        environmental health or safety risks
                        addressed by this action present a
                        disproportionate risk to children.
                         The topic of environmental threats to
                        children's health is growing in
                        regulatory importance as scientists,
                        policy makers, and village leaders
                        continue to recognize the extent to
                        which children are particularly
                        vulnerable to environmental hazards.
                        Recent EPA actions have been in the
                        forefront of addressing environmental
                        threats to the health and safety of
                        children. Today's proposed rule further
                        reflects our commitment to mitigating
                        environmental threats to children.
                         A few significant physiological
                       characteristics are largely responsible
                       for children's increased susceptibility to
                       environmental hazards. First, children
                       eat proportionately more food, drink
                       proportionately more fluids, and breathe
                       more air per pound of body weight than
                       do adults. As a result, children
                       potentially experience greater levels of
                       exposure to environmental threats than
                       do adults. Second, because children's
                       bodies are still in the process of
                       development, their immune systems,
                       neurological systems, and other
                       immature organs can be more easily and
                       considerably affected by environmental
                       hazards.
                         Today's proposed rule will reduce
                       risks posed by the hazardous
                       constituents found in the listed waste
                       streams by requiring more appropriate
                       and safer management practices. EPA
                       considered risks to children in its risk
                       assessment. The more appropriate and
                       safer management practices proposed in
                       this rule are projected to reduce risks to
 children potentially exposed to the
 constituents of concern. The public is
 invited to submit or identify peer-
 reviewed studies and data, of which the
 agency may not be aware, that assess
 results of early life exposure to the
 proposed hazardous constituents from
 wastewaters and wastewater treatment
 sludges from the production of
 chlorinated aliphatic chemicals.

 H. National Technology Transfer and
 Advancement Act of 1995 •
   Section 12(d) of the National
 Technology Transfer and Advancement
 Act of 1995 ("NTTAA"), Pub. L. No.
 104-113, Section 12(d)  (15 U.S.C. 272
 note) directs EPA to use voluntary
 consensus standards in  its regulatory
 activities, unless to do so would be
 inconsistent with applicable law or
 otherwise impractical. Voluntary
 consensus standards are technical
 standards (e.g., materials specifications,
 test methods, sampling  procedures, and
 business practices)  that  are developed or
 adopted by voluntary consensus
 standards bodies. The NTTAA directs
 EPA to provide Congress, through OMB,
 explanations when the Agency decides
 not to use available and applicable
 voluntary consensus standards.
   This proposed rulemaking does not
 involve technical standards. Therefore,
 EPA is not considering the use of any
 voluntary consensus standards.

 I. Executive Order 12898:
 Environmental Justice
   Under Executive Order 12898,
 "Federal Actions to Address
 Environmental Justice in Minority
 Populations and Low-Income
 Populations," as well as through EPA's
 April 1995, "Environmental Justice
 Strategy, OSWER Environmental Justice
 Task Force Action Agenda Report," and
 National Environmental Justice
 Advisory Council, EPA has undertaken
 to incorporate environmental justice
 into its policies and programs. EPA is
 committed to addressing environmental
justice concerns, and is assuming a
 leadership role in environmental justice
 initiatives to enhance environmental
 quality for all residents of the United
 States. The Agency's goals are to ensure
 that no segment of the population,
 regardless of race, color,  national origin,
 or income, bears disproportionately
 high and adverse human health and
 environmental effects as a result of
 EPA's policies,  programs, and activities.
  Today's proposed rule is intended to
reduce risks of hazardous wastes as
proposed, and to benefit  all populations.
As such, this rule is not expected to
cause any disproportionately high  and
adverse impacts to minority or low-

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                 Federal Register/Vol. 64. No.  164/Wednesday, August 25,  1999/Proposed Rules
                                                                       46531
  income communities versus non-
  minority or affluent communities.
    In making hazardous waste listing
  determinations, we base our evaluations
  of potential risk from the generation and
  management of solid wastes on an
  analysis of potential individual risk. In
  conducting risk evaluations, our goal is
  to estimate potential risk to any
  population of potentially exposed
  individuals (e.g., home gardeners, adult
  farmers, children of farmers, anglers)
  located in the vicinity of any generator
  or facility handling a waste. Therefore,
  we are not putting poor, rural, or
  minority populations at any
  disadvantage with regard to our
  evaluation of risk or with regard to how
  the Agency makes its proposed
  hazardous waste listing determinations.
    In proposing today to list three wastes
  as hazardous (i.e., chlorinated aliphatic
  wastewaters, EDC/VCM wastewater
  treatment sludges managed in land
  treatment units, and VCM-A wastewater
  treatment sludges), all populations
  potentially exposed to these wastes or
  potentially exposed to releases of the
  hazardous constituents in the wastes
  will benefit from the proposed listing
  determination. In addition, listing
  determinations are effected at the
  national level. The wastes proposed to
  be listed as hazardous will be hazardous
  regardless of where they are generated
 and regardless of where they may be
 managed. Although the Agency
 understands that the proposed listing
 determinations, if finalized, may affect
 where these wastes are managed in the
 future (in that hazardous wastes must be
 managed at subtitle C facilities), the
 Agency's decision to list these wastes as
 hazardous is independent of any
 decisions regarding the location of
 waste generators and the siting of waste
 management facilities.
   Similarly, in cases where the Agency
 is proposing not list a solid waste as
 hazardous because the waste does not
 meet the criteria for being identified as
 a hazardous waste, these decisions are
 based upon an evaluation of potential
 individual risks located in proximity to
 any facility handling the waste.in the
 case of wastewater treatment sludges
 from the production of allyl chloride
 and methyl chloride and the case of
 EDC/VCM. wastewater treatment sludges
 managed in landfills, we believe the
 potential risk levels associated with the
 wastes are safe for all populations
 potentially exposed to the wastes and
 their constituents.
  The Agency is soliciting comment and
 input from all stakeholders, including
 members of the environmental justice
community and members of the
regulated community. We encourage all
  interested parties to provide comments
  or further information related to
  potential environmental justice
  concerns orimpacts, including
  information and data on facilities that
  have evaluated potential ecological and
  human health impacts (taking into
  account subsistence patterns and
  sensitive populations)  to minority or
  low-income communities.

  List of Subjects

  40 CFR Part 148

    Administrative practice and
  procedure, Hazardous waste. Reporting
  and recordkeeping requirements, Water
  supply.

  40 CFR Part 261

    Environmental protection. Hazardous
  materials. Recycling, Waste treatment
  and disposal.

  40 CFR Part 264

    Environmental protection, Air
  pollution control. Hazardous waste.
  Insurance, Packaging and containers,
  Reporting and recordkeeping
  requirements, Security measures, Surety
  bonds.

  40 CFR Part 265

   Air pollution control, Hazardous
 waste. Insurance, Packaging and
 containers. Reporting and recordkeeping
 requirements, Security measures. Surety
 bonds, Water supply.

 40 CFR Part 268

   Environmental protection, Hazardous
 materials. Reporting and recordkeeping
 requirements, Waste management.

 40 CFR Part 271

   Environmental protection.
 Administrative practice  and procedure,
 Confidential business information,  '
 Hazardous material transportation,
 Hazardous waste, Indians-lands,
 Intergovernmental relations, Penalties,
 Reporting and recordkeeping
 requirements. Water pollution control,
 Water supply.

 40 CFR Part 302
  Environmental protection. Air
pollution control, Chemicals, Hazardous
chemicals, Hazardous materials.
Hazardous materials transportation.
Hazardous substances, Hazardous
waste, Intergovernmental relations,
Natural resources. Reporting and
recordkeeping requirements, Superfund,
Waste treatment and disposal. Water
pollution control. Water supply. -
    Dated: July 30, 1999.
  Carol M. Browner,
  Administrator.
    For the reasons set forth in the
  preamble, title 40, chapter I of the Code
  of Federal Regulations^ proposed to be
  amended as follows: ~

  PART 148—HAZARDOUS WASTE
  INJECTION RESTRICTIONS

    1. The authority citation for part 148
  continues to read as follows:
    Authority: Sec. 3004, Resource
  Conservation and Recovery Act, 42 U.S C
  6901 etseq.
    2. Section 148.18 is amended by
  adding paragraphs (1) and (m) to read as
  followst

  § 148.18  Waste-specific prohibitions—
  newly listed and identified wastes.
  *****
    (1) Effective  [date six months after
  publication of final rule], the wastes
  specified in 40 CFR 261.32 as EPA
  Hazardous Waste Numbers K173, K174,
  and K175 are prohibited from
  underground injection.
    (m) The requirements of paragraphs
  (a) through (1) of this section do not
  apply:
    (1) If the wastes meet or are treated to
  meet the applicable standards specified
  in subpart D of part 268 of this chapter;
  or
    (2) If an exemption from a prohibition
  has been granted in response to a
 petition under subpart C of this part; or
    (3) During the period of extension of
 the applicable effective date, if an
 extension has been granted under
 §148.4.

 PART 261—IDENTIFICATION AND
 LISTING OF HAZARDOUS WASTE

  3. The authority citation for part 261
 continues to read as follows:
  Authority: 42 U.S.C. 6905, 6912(a), 6921
 6922, 6924(y), and 6938.
  4. Section 261,3 is amended by
 adding a paragraph (c) (2) (ii) (F) to read
 as follows:

 § 261.3  Definition of hazardous waste.
 *****
  (c) * * *
  (2)***
  (ii) * * *
  (F) Wastewater treatment sludges
 derived from the treatment of
 chlorinated aliphatic wastewaters listed
 in §261.32 as EPA Hazardous Waste No.
K173. However, this paragraph does not
exempt from the definition of hazardous
waste any wastewater treatment sludges
that are explicity listed (e.g., K174,
Kl 75) or that meet any other listing in

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subpart D of this part, as a result of the
derived-from rule.
*     *    *     *     *

   5. Section 261.4 is amended by
revising paragraph (b)(15)  to read as
follows:

§261.4 Exclusions.
*****

   (b)***
   (15) Leachate or gas condensate
collected from landfills where certain
solid wastes have been disposed,
provided that:
   (i) The solid wastes disposed would
meet one or more of the listing
descriptions for Hazardous Waste Codes
K169, K170. K171. K172, K174, and
K175 if these wastes had been generated
after the effective date of the listing;
   (ii) The solid wastes described in
paragraph (b)(15)(i) of this section were
                          disposed prior to the effective date of
                          the listing:
                            (iii) The leachate or gas condensate do
                          not exhibit any characteristic of
                          hazardous waste nor are derived from
                          any other listed hazardous waste;
                            (iv) Discharge of the leachate or gas
                          condensate, including leachate or gas
                          condensate transferred from the landfill
                          to a POTW by truck, rail, or dedicated
                          pipe, is subject to regulation under
                          Sections 307 (b) or 402 of the Clean
                          Water Act.
                            (v) After February 13, 2001, leachate
                          or gas condensate derived from K169-
                          K172 will no longer be exempt if it is
                          stored or managed in a surface
                          impoundment prior to discharge. After
                          [date 24 months after publication date of
                          the final rule], leachate or gas
                          condensate derived from K175 will no
                          longer be exempt if it is stored or
                          managed in a surface impoundment
prior to discharge. There is one
exception: if the surface impoundment
is used to temporarily store leachate or
gas condensate in response to an
emergency situation (e.g., shutdown of
wastewater treatment system), provided
the impoundment has-a double liner,
and provided the leachate or gas
condensate is removed from the
impoundment and continues to be
managed in compliance with the
conditions of this paragraph (b) (15) (v)
after the emergency ends.
*****

  6. In §261.32, the table is amended by
adding in alphanumeric order (by the
first column) the following waste
streams to the subgroup "Organic
Chemicals" to read as follows:

§ 261.32  Hazardous waste from specific
sources.
*****
  Industry and
 EPA hazardous
   waste No.
                                         Hazardous waste
                                Hazard
                                 code
Organic Chemi-
  cals:
    K173
    K174
    K175
Wastewaters from the production of chlorinated aliphatic hydrocarbons, except wastewaters generated from the (T)
  production of vinyl chloride monomer using mercuric chloride catalyst in an acetylene-based process. This list-
  ing includes wastewaters from the production of chlorinated aliphatic hydrocarbons having carbon chain lengths
  ranging from one to and including five, with varying amounts and positions of chlorine substitution
Wastewater treatment sludges  from the production of ethylene dichloride or vinyl chloride monomer (including (T)
  sludges that result from commingled ethylene  dichloride or vinyl chloride  monomer wastewater and other
  wastewater), unless the sludges meet the following conditions: they are disposed of in a subtitle C or D landfill
  licensed or permitted by the  state or federal government; they are not  otherwise placed on the land  prior to
  final disposal; and the generator maintains documentation demonstrating that the waste was either disposed of
  in an on-site landfill or consigned to a transporter or disposal facility that provided a written commitment to dis-
  pose of the waste in an off-site landfill. Respondents in any action brought to enforce the requirements of sub-
  title C must, upon a showing by  the government that  the respondent managed wastewater treatment sludges
  from the production of vinyl chloride  monomer or ethylene dichloride, demonstrate that they meet the terms of
  the exclusion set forth above. In doing so, they must provide appropriate documentation (e.g., contracts be-
  tween the generator and the landfill owner/operator, invoices documenting delivery of waste to landfill, etc.) that
  the terms  of the exclusion were met
Option 1: Wastewater treatment sludges from the production of vinyl chloride monomer using mercuric chloride (T)
  catalyst in an acetylene-based process.
Option 2: Wastewater treatment sludges from the production of vinyl chloride monomer using mercuric chloride (T)
  catalyst in an acetylene-based process, unless the sludges are disposed  in a subtitle C landfill; and  the
  sludges do not fail the toxicity characteristic for mercury in 40 CFR 261.24; and the generator maintains docu-
  mentation demonstrating that  the  waste was disposed of in a subtitle C landfill or consigned to a transporter or
  disposal facility that provided a written commitment to dispose of the waste in a subtitle C landfill. Respondents
  in any action brought to enforce the  requirements of subtitle C must, upon a showing by the government that
  the respondent  managed wastewater treatment sludges from the  production of vinyl chloride monomer using
  mercuric chloride catalyst in an acetylene-based process, demonstrate that they meet the terms of the exclu-
  sion set forth above. In doing so, they must provide appropriate  documentation (e.g., contracts between the
  generator  and the landfill owner/operator, invoices documenting delivery of waste to landfill, analytical results or
  other information showing the waste  does not fail the toxicity characteristic for mercury, etc.) that the terms of
  the exclusion were met
    7.  Appendix VII to  Part  261  is  amended by  adding  the following  wastestreams  in alphanumeric order  (by the
first column) to read as follows:

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                 Federal  Register/VoL  64,  No.  164/Wednesday.  August 25, 1999 /Proposed Rules        46533

                               Appendix VII to Part 261—Basis for Listing Hazardous Waste
   EPA hazardous
     waste No.
             Hazardous constituents for which listed
                                                                                            ^                *
  K173 	  1,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin   (1,2,3,4,6,7,8-HpCDD),   1,2,3,4,6,7,8-Heptachlorodibenzofuran  (1234678-
                   ^P™?'  ^2'3'4-7'8.9-HePtachloradibenzofuran  (1,2,3,6,7,8,9-HpCDF),  HxCDDs  (All  Hexachlorodibenzo-Wdioxins)
                   HxCDFs  (All   Hexachlorodibenzofurans),  PeCDDs  (All  Pentachlorodibenzo-p-dioxins)   OCDD  (12346789
                   °°te£hl°r°dibenz°-^di°xin. OCDF  (1'2'3-4'6'7.8.9-Octachlorodibenzofuran),  PeCDFs  (All  Pentachlorodibenzofuran's)
                   TCDDs (All tetrachlorodi-benzo-p-dioxins), TCDFs (All tetrachlorodibenzofurans)                      '
  K174 	  1,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin   (1,2,3,4,6,7,8-HpCDD),   1,2,3,4,6,7,8-Heptachlorodibenzofuran  (1234678-
                   uP™?'  );2,3,4,7,8,9'Heptachlorodiben2ofuran  (1,2,3,6,7,8,9-HpCDF),  HxCDDs  (All  Hexachlorodibenzc-^dioxins)
                   HxCDFs   (All   Hexachlorodibenzofurans),  PeCDDs  (All  Pentachlorodibenzo-p-dioxins)   OCDD  (1234678 9
                   Octachlorodibenzo-p-dioxin, OCDF  (1,2,3,4,6,7,8,9-Octachlorodibenzofuran) PeCDFs  (All  Pentachlorodibenzofuran's)
                   TCDDs (All tetrachlorodi-benzo-jOdioxins), TCDFs (All tetrachlorodibenzofurans)                           *
  K175 	  Mercury

     8. Appendix VIII to part 261 is amended by adding in alphabetical sequence of common  name the following entries:

                                   Appendix VIII to Part 261—Hazardous Constituents
                 Common name
                                                          Chemical abstracts name
                                                      Chemical
                                                      abstracts
                                                        No.
                            Hazardous
                            waste No.
 Octachlorodibenzo-jD-dioxin (OCDD)  	  1,2,3,4,6,7,8,9-Octachlorodibenzo-/>dioxin	         3268-87-9
 Octachlorodibenzofuran (OCDF)	  1,2,3,4,6,7,8,9-Octachlorodibenzofuran 	   39001-02-0
 PART 264—STANDARDS FOR
 OWNERS AND OPERATORS OF
 HAZARDOUS WASTE TREATMENT,
 STORAGE, AND DISPOSAL
 FACILITIES

   9. The authority citation for part 264
 continues to read as follows:
   Authority: 42 U.S.C. 6905, 6912(a), 6924,
 and 6925.

 Subpart A—General

   10. Section 264.1 is amended by
 adding a sentence to the end of
 paragraph (g) (6) to read as follows:

 § 264.1  Purpose, scope and applicability.
 *****

   (g) * *  *
   (6) * *  * However,  if the owner or
 operator is managing EPA Hazardous
 Waste No. K173 (chlorinated aliphatic
 wastewater) in a tank,  the owner/
 operator must comply with
 §264.1080(h).
Subpart CO—Air Emission Standards
for Tanks, Surface Impoundments, and
Containers

  11. Section 264.1080 is amended by
adding paragraph (h) to read as follows:
 §264.1080  Applicability.
 *    *     *     *     *
   (h) Notwithstanding the applicability
 requirements in paragraph (a) of this
 section, any tank (including wastewater
 treatment units as defined in §260.10 of
 this chapter) managing EPA Hazardous
 Waste No. K173, where the dioxin
 concentration in the influent wastewater
 to the tank is greater than or equal to 1
 ng/L TCDD TEQ at a 95% upper '
 confidence limit around the mean, must
 comply with the requirements of this
 paragraph, and with §264.1084 as
 appropriate. In order to determine
 whether the influent concentration of
 EPA Hazardous Waste No. K173 is
 greater than or equal to 1 ng/L TCDD
 TEQ at a 95% upper confidence limit
 around the mean, the generator or
 owner/operator must comply with the
 requirements in 40  CFR 265.1080(h)(l)
 through (5).

 PART 265—INTERIM STATUS
 STANDARDS FOR OWNERS AND
 OPERATORS OF HAZARDOUS WASTE
 TREATMENT, STORAGE,  AND
 DISPOSAL FACILITIES

  12. The authority citation for part 265
continues to read as follows:
  Authority: 42 U.S.C. 6905, 6906, 6912,
6922, 6923. 6924, 6925, 6935,  6936, and
6937, unless otherwise noted.
 Subpart A—General
   13. Section 265.1 is amended by
 adding a sentence to the end of
 paragraph (c) (10) to read as follows:

 §265.1  Purpose, scope, and applicability.
 *****
   (c) * * *
   (10) * * * However, if the owner or
 operator is managing EPA Hazardous
 Waste No. K173 (chlorinated aliphatic
 wastewater) in a tank, the owner/
 operator must comply with
 §265.1080(h).
 Subpart CC—Air Emission Standards
 for Tanks, Surface Impoundments, and
 Containers

   14. Section 265.1080 is amended by
 adding paragraph (h) to read as follows:
 §265.1080  Applicability
 *****
   (h) Notwithstanding the applicability
 requirements in paragraph (a) of this
 section, any tank (including wastewater
 treatment units as defined in §260.10 of
 this chapter) managing EPA Hazardous
 Waste No. K173, where the dioxin
 concentration in the influent wastewater
 to the tank  is equal to or greater than 1
ng/L TCDD TEQ at a 95% upper
confidence limit around the mean, must

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 46534
Federal  Register/Vol. 64, No.  164/Wednesday, August 25,  1999 /Proposed  Rules
 comply with the requirements of this
 paragraph, and with §265.1085 as
 appropriate. In order to determine
 whether the influent concentration of
 EPA Hazardous Waste No. K173 is
 greater than or equal to 1 ng/L TCDD
 TEQ at a 95% upper confidence limit
 around the mean, the generator or
 owner/operator must comply with the
 following:
   (1) Waste sampling and analysis
 plans, (i) General. The generator of Kl 73
 shall develop and follow a written waste
 sampling and analysis plan which
 describes the procedures for sampling
 and analysis of the hazardous waste at
 the influent to  each wastewater
 treatment tank to be excluded from the
 requirements of this part. The waste
 sampling and analysis plan shall be
 developed in accordance with the
 applicable sections of the "Test
 Methods for Evaluating Solid Waste,
 Physical/Chemical Methods" (SW-846)
 or other appropriate guidance. The plan
 shall be followed and retained at the
 facility claiming an exemption for one
 or more wastewater treatment tanks.
   (ii) At a minimum, the plan must
 include:
   (A) A detailed description of the test
 method(s) used to test for 2,3,7,8-
 substituted chlorinated dibenzo-p-
 dioxin (CDD) and 2.3,7.8-substituted
 chlorinated dibenzo-p-furan (CDF)
 congeners;
   (B) The sampling method used to
 obtain representative samples of each
 wastewater tank influent; and
   (C) How  the design of the sampling
 program accounts for any expected
 fluctuations in  concentrations over time,
 while ensuring that the samples
 collected are grab samples and that all
 samples are collected within a
 timeframe that  will allow for the
 analyses to account for potential
 variabilities in the wastestream.
   (2) Sampling and analysis, (i)
 General. For each wastewater treatment
 tank for which an exemption is claimed,
 the generator of K173 must:
   (A) Test for all 2,3,7,8-substituted
 CDDs/CDFs; or
   (B) Use process knowledge for tanks
 downstream of a tank that is exempt as
 a result of testing specified in paragraph
 (h)(2)(i)(A)  of this section.
   (ii) The K173 generator may use any
 reliable analytical method to
 demonstrate that the TCDD TEQ does
 not exceed the trigger level. It is the
 responsibility of the generator to ensure
 that the sampling and analysis are
 unbiased, precise, and representative of
 the waste.
   (Hi) The generator must ensure that
the measurements are sufficiently
sensitive, accurate and precise to
                        demonstrate that the maximum TCDD
                        TEQ in any sample analyzed does not
                        exceed the specified trigger level.
                          (iv) For the tank to be eligible for
                        exemption, a generator must
                        demonstrate that:
                          (A) The maximum TCDD TEQ in the
                        influent to the tank does not exceed 1
                        ng/L at the 95% upper confidence limit
                        around the mean;
                          (B) The TCDD TEQ for each sample
                        shall be determined by multiplying the
                        concentration of any 2,3,7,8-substituted
                        CDD or CDF detected and the
                        appropriate toxicity equivalency factor
                        (TEF), as described below, and summing
                        these products for each sample;
                          (C) The following toxicity equivalence
                        factors shall be used:
Compound
2 3,7,8-TetraCDD 	
1237 8-PentaCDD
1 2 3,4,7 8-HexaCDD 	
12378 9-HexaCDD
1,2,3,6,7,8-HexaCDD 	
1 23467 8-HeptaCDD
1 234578 9-OctaCDD
237 8-TetraCDF
2,3,4,7,8-PentaCDF 	
1 ,2,3,7,8-PentaCDF 	
1 ,2,3,4,7,8-HexaCDF 	
1,2,3,7,8,9-HexaCDF 	
1 ,2,3,6,7,8-HexaCDF 	
23467 8-HexaCDF
1 23478 9-HeptaCDF
1 ,2,3,4,6,7,8-HeptaCDF 	
1 ,2,3,4,6,7,8,9-OctaCDF 	

WHO-TEF
1
1
0.1
01
0.1
001
00001
0.1
0.5
0.05
0.1
0.1
0.1
01
001
0.01
0.0001

                         (D) The analysis could have detected
                       the presence of the CDD/CDF congeners
                       at or below the trigger level of 1 ng/L at
                       the 95% upper confidence limit around
                       the mean.
                         (v) In an enforcement action, the
                       burden of proof to establish
                       conformance with the exemption
                       specification shall be on the generator
                       claiming the exclusion.
                         (vi) The generator must conduct
                       sampling and analysis in accordance
                       with their waste sampling and analysis
                       plan developed under paragraph (h) (1)
                       of this section.
                         (vii) The influent to exempt
                       wastewater treatment tanks must be re-
                       tested, at a minimum, annually and
                       must be retested after a process change
                       that could change the TCDD TEQ level
                       in the waste.
                         (3) Records. The generator must
                       maintain records of the following
                       information on-site:
                         (i) All information required to be
                       submitted to the implementing
                       authority as part of the notification of
                       the claim:
                         (A) The owner/operator name,
                       address, and RCRA facility ID number of
                       the person claiming the exemption; and
   (B) The certification signed by the
 person claiming the exclusion or his
 authorized representative.
   (ii) A brief description of the tanks
 covered by the claimed exemption,
 including dimensions and service in the
 wastewater treatmentisystem;
   (iii) A description and  process flow
 diagram of the wastewater treatment
 system, clearly identifying the exempt
 tanks and sampling points;
   (iv) The results of all analyses and all
 detection limits achieved as required
 under paragraph (h) (2) of this section;
   (v) The waste sampling and analysis
 plan;
   (vi) The results of the sampling and
 analysis, including the following:
   (A) The dates and times waste
 samples were obtained, and the dates
 the samples were analyzed;
   (B) The names and qualifications of
 the person(s) who obtained the samples;
   (C) A description of the temporal and
 spatial locations of the samples;
   (D) The name and address of the
 laboratory facility at which analyses of
 the samples were performed;
   (E) A detailed description of the
 analytical methods used,  including any
 clean-up and sample preparation
 methods;
   (F) All quantitation limits achieved
 and all other quality control results for
 the analysis (including method blanks,
 duplicate analyses, matrix spikes, etc.),
 laboratory quality assurance data, and
 description of any deviations from
 analytical methods written in the plan
 or from any other activity written in the
 plan which occurred;
   (G) All laboratory analytical results
 demonstrating that the trigger
 exemption level has not been exceeded
 at the tank influent, for each exempt
 tank; and
   (H) All laboratory documentation that
 support the analytical results, unless a
 contract between the claimant and the
 laboratory provides for the
 documentation to be maintained by the
 laboratory for the period specified in
 paragraph (h) (4) of this section and also
 provides for the availability of the
 documentation to the claimant upon
 request; and
  (4) Records retention. Records must
 be maintained for the period of three
years. A generator must maintain a
 current waste sampling and analysis
plan during that three year period.
  (5) Notification and certification. The
waste generator must submit a one-time
notification and certification to the EPA
Region or an authorized State (by mail
or delivery service which  provides
return receipt) within 60 days following
the effective date of the final rule or
initial use of a wastewater treatment

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                Federa] Register/Vol.  64,  No.  164/Wednesday, August 25,  1999 /Proposed Rules
                                                                        46535
 tank used to manage K173. The
 notification must include the waste
 generator's name and address, a
 representative's name and telephone
 number, and a description of the
 wastewater treatment system and the
 assessed tanks. The certification must be
 signed by an authorized representative
 and must state as follows:
 I certify under penalty of law that the
 influent (s) to the tanks identified in this
 certification do not exceed 1 ng/L TCDD
 TEQ. I am aware that there are significant
 penalties for submitting a false, inaccurate, or
 incomplete certification, including the
 possibility of fine .and imprisonment.

 PART 268—LAND DISPOSAL
 RESTRICTIONS

   15. The authority citation for part 268
 continues to read as follows:
  Authority: 42 U.S.C. 6905, 6912(a), 6921,
 and 6924.

 Subpart A—General

   16. Section 268.7 is amended by
 adding paragraph (f) to read as follows:

 §268.7  Testing, tracking, and
 recordkeeping requirements for generators,
 treaters, and disposal facilities.
 *****

  (f) The owner or operator of a facility
 codisposing wastes with wastes
 identified as hazardous waste Kl 75
 must maintain records available for
 inspection of the pH of the wastes so
 codisposed.
 Subpart C—Prohibitions on Land
 Disposal

    17. Section 268.33 is revised to read
 as follows:

 § 268.33  Waste specific prohibitions-
 chlorinated aliphatic wastes.
   (a) Effective [date 90 days from date
 of publication of final rule], the wastes
 specified in 40 CFR Part 261 as EPA
 Hazardous Wastes Numbers K173,
 K174, and K175, and soil and debris
 contaminated with these wastes are
 prohibited from land disposal.
   (b) Effective [date two years from date
 of publication of final rule], the
 following wastes are prohibited from
 land disposal: soil and debris
 contaminated with radioactive wastes
 mixed with EPA Hazardous wastes
 K173, K174, andK175.
   (c) Between [date of publication of
 final rule] and [Insert date two years
 from date of publication of final rule],
 radioactive waste mixed with K173,
 K174, and K175 wastes and/or soil and
 debris may be disposed in a landfill or
 surface impoundment only  if such unit
 is in compliance with the requirements
 specified in § 268.5 (h) (2).
   (d) The requirements of paragraphs
 (a), (b) and (c) of this section do not
 apply if:
  (1) The wastes meet the applicable
 treatment standards specified in subpart
 D of this part;
  (2) Persons have been granted an
 exemption from a prohibition pursuant
to a petition under §268.6, with respect
to those wastes and units covered by the
petition;
  (3) The wastes meet the applicable
treatment standards established
   pursuant to a petition granted under
   §268.44;
      (4) Hazardous debris has met the
   treatment standards in §268.40 or the
   alternative treatment standards in
   §268.45; or
      (5) Persons have been granted an
   extension to the effective date of a
   prohibition pursuant to §268.5, with
   respect to these wastes covered by the
   extension.
      (e) To determine whether a hazardous
   waste identified in this section exceeds
   the applicable treatment standards
   specified in §268.40, the initial
   generator must test a sample of the
   waste extract or the entire waste,
   depending on whether the treatment
   standards are expressed as
   concentrations in the waste extract or
   the waste, or the generator may use
   knowledge of the waste. If the waste
   contains regulated constituents in
   excess of the applicable Universal
   Treatment Standard levels of §268.48,
   the waste is prohibited from land
   disposal,  and all requirements of this
   part are applicable, except as otherwise
   specified.
     (f) Disposal of Kl 75 wastes containing
   mercuric  sulfide is restricted to units to
   which disposal of wastes in excess of
   pH 6.0 is  prohibited.
     18. In §268.40, the Table is amended
   in the entry for F039 to add constituents
   in alphabetical order and by adding in
   alphanumeric order new entries for
   K173, K174, and K175 to read as
  follows:

  § 268.40 Applicability of treatment
  standards.
                                  TREATMENT STANDARDS FOR HAZARDOUS WASTES
                                                    Regulated hazardous constituent
                                                  Wastewaters   Nonwastewaters
Waste
code
Waste description and treatment/regu-
latorysubcategory' Common name
Concentration
CAS 2 No '" m^ or
technology
code4
Concentration in
mg/kg5 unless
noted as "mg/L
TCLP", or tech-
nology code
F039 	  Leachate (liquids that have percolated
            through  land disposed wastes) re-
            sulting from  the disposal of  more
            than one restricted waste classified
            as  hazardous under Subpart  D of
            this part. (Leachate resulting  from
            the disposal of one or more of the
            following  EPA Hazardous  Wastes
            and no other Hazardous Waste re-
            tains  its  EPA Hazardous Waste
            Number(s):   F020,  F021,  F022,
            F026, F027, and/or F028) * * *.
   1,2,3,4,6,7,8-Heptachlorodibenzo-yO
     dioxin (1,2,3,4,6,7,8-HpCDD).
35822-39-4
                0.000035  0.0025
                                          1,2,3,4,6,7,8-Heptachlorodibenzofuran
                                            (1,2,3,4,6,7,8-HpCDF).
                                          1,2,3,4,7,8,9-Heptachlorodibenzofuran
                                            (1,2,3,4,7,8,9-HpCDF).
                                     67562-39-4

                                     55673-89-7
                0.000035  0.0025

                0.000035  0.0025

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46536
      Federal Register/Vol.  64, No.  164/Wednesday, August  25, 1999/Proposed Rules
                               TREATMENT STANDARDS FOR HAZARDOUS WASTES—Continued
                                                         Regulated hazardous constituent
                                                                                       Wastewaters   Nonwastewaters
Waste
code
Waste description and treatment/regu-
latory subcategory' Common name
Concentration
rAq2 MO in m9/L'3 or
OAb IMO. technology-
code4
Concentration in
mg/kg s unless
noted as "mg/L
TCLP", or tech-
nology code
                                               1,2,3,4,6,7,8,9-Octachlorodibenzo-/c>-       3268-87-9
                                                 dioxin (OCDD).
                                               1,2,3,4,6,7,8,9-                         39001-02-0
                                                 Octachlorodibenzofuran (OCDF).
                                                                                           0.000063  0.0025

                                                                                           0.000063  0.005
K173
Wastewaters from  the  production of
  chlorinated aliphatic hydrocarbons,
  except Wastewaters generated from
  the production   of  vinyl  chloride
  monomer using  mercuric  chloride
  catalyst in an acetylene-based proc-
  ess.    This     listing     includes
  Wastewaters from the production of
  chlorinated  aliphatic  hydrocarbons
  having carbon chain  lengths rang-
  ing from one to and including five,
  with varying amounts and positions
  of chlorine substitution.
                                    Bis(2-chloroethyl)ether
                                                                                       111
                                                                                                         0.033  6.0
K174
Wastewater  treatment sludges  from
  the production of ethylene  dichlo-
  ride or vinyl chloride monomer.
                                               Chloroform ...........................................
                                               Pentachlorophenol ..............................
                                               Phenol .................................................
                                               2,4,6-Trichlorophenol ..........................
                                               1,2,3,4,6,7,8-Heptachlorodibenzo-p-
                                                 dioxin (1 ,2,3,4,6,7,8-HpCDD).
                                               1,2,3,4,6,7,8-Heptachlorodibenzofuran
                                                 (1,2,3,4,6,7,8-HpCDF).
                                               1,2,3,4,7,8,9-Heptachlorodibenzofuran
                                                 (1,2,3,4,7,8,9-HpCDF).
                                               HxCDDs (All Hexachloro- .................. .
                                               dibenzo-yodioxins) 34465-46-8 ..........
                                               HxCDFs (All Hexachloro- ....................
                                               dibenzofurans) .....................................
                                               1,2,3,4,6,7,8,9-Octachlorodibenzo-p-
                                                 dioxin (OCDD).
                                               1,2,3,4,6,7,8,9-
                                                 Octachlorodibenzofuran (OCDF).
                                               PeCDDs (All Pentachloro- ..................
                                               dibenzo-p-dioxins) ...............................
                                               PeCDFs (All Pentachloro- ...................
                                               dibenzofurans) .....................................
                                               TCDDs (All tetrachloro- .......................
                                               di-benzo-yO-dioxins) ..............
                                               TCDFs (All tetrachloro-  .......................
                                               dibenzofurans) .....................................
                                               Chromium (Total) ................................
                                               Nickel [[[
                                                dioxin (1 ,2,3,4,6,7,8-HpCDD).

                                               1,2,3,4,6,7,8-Heptachlorodibenzofuran
                                                (1,2,3,4,6,7,8-HpCDF).
                                               1,2,3,4,7,8,9-Heptachlorodibenzofuran
                                                (1,2,3,4,7,8,9-HpCDF).
                                               HxCDDs (All Hexachloro-  ...................
                                               dibenzo-/>dioxins) ...............................
                                               HxCDFs (All Hexachloro- ....................
                                               dibenzofurans) .....................................
                                               1,2,3,4,6,7,8,9-Octachlorodibenzo-p-
                                                dioxin (OCDD).
                                               1,2,3,4,6,7,8,9-
                                                Octachlorodibenzofuran (OCDF).
                                                                             67-66-3
                                                                             87-86-5
                                                                            108-95-4
                                                                             88-06-2
                                                                         35822-39-4

                                                                         67562-39-4

                                                                         55673-89-7

                                                                            0.000063

                                                                         55684-94-1

                                                                          3268-87-9

                                                                         39001-02-0

                                                                         36088-22-9

                                                                         30402-15-4

                                                                            0.000063

                                                                         55722-27-5

                                                                          7440-47-3
                                                                          7440-02-0
                                                                         35822-39-4


                                                                         67562-39-4

                                                                         55673-89-7

                                                                         34465-46-8

                                                                         55684-94-1

                                                                          3268-87-9

                                                                         39001-02-0
0.046
0.089
0.039
0.035
0.000035
0.000035
0.000035
0.001
0.000063
0.000063
0.000063
0.000063
0.000035
0.001
0.000063
2.77
3.98
0.000035
0.000035
0.000035
0.000063
0.000063
0.000063
0.000063
6.0
7.4
6.2
7.4
0.0025
0.0025
0.0025

0.001
0.005
0.005
0.001
0.001

0.001
0.60 mg/L TCLP

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                 Federal Register/Vol.  64, No. 164/Wednesday, August 25, 1999/Proposed Rules
                                                                            46537
                               TREATMENT STANDARDS FOR HAZARDOUS WASTES—Continued
                                                         Regulated hazardous constituent
                                                       Wastewaters   Nonwastewaters
Waste Waste description and treatment/regu-
code latorysubcategory' Common name
PeCDDs (All Pentachloro- 	
dibenzo-/>dioxins) 	 	
PeCDFs (All Pentachloro- 	
dibenzofurans) 	
TCDDs (All tetrachlorodi-benzo-/>
dioxins).
TCDFs (All tetrachlorodibenzofurans)
Arsenic 	
K175 	 K175 (wastewater treatment sludge Mercury 	
C
CAS 2 No.
36088-22-9

30402-1 5-4

41903-57-5
- 55722-27-5
7440-36-0
7438-97-6
Concentration
in mg/L,3 or
technology.
code4
0 000063

0 000035

0.000063
0.000063
1 4
NA
Concentration in
mg/kg5 unless
noted as "mg/L
TCLP", or tech-
nology code
0 001

0 001

0.001
0.001
"? f) mn/l TCI P
RMFRO
             from the production of vinyl chloride
             monomer  using  mercuric  chloride
             catalyst in an acetylene-based proc-
             ess) nonwastewaters that contain
             greater than or equal to 260 mg/kg
             total mercury.
           K175  nonwastewaters  that  contain
             less than 260 mg/kg total  mercury
             that are residues from RMERC.
           Other K175 nonwastewaters that con-
             tain less than 260 mg/kg total mer-
             cury and  are not  residues from
             RMERC.
    Mercury


    Mercury
7438-97-6
7438-97-6
           All K175 wastewaters
    PH 	
    Mercury
                                                                                    7438-97-6
                      NA  0.20 mg/L TCLP
                      NA  0.025 mg/L
                            TCLP
                     NA  pH <6.0
                    0.15  NA
  * Note: NA means not applicable.
  1The waste descriptions provided in this table do not replace waste descriptions in 40 CFR Part 261. Descriptions of Treatment/Requlatorv
 Subcategories are provided, as needed, to distinguish between applicability of different standards.
  2 CAS means Chemical Abstract  Services. When the waste code and/or regulated constituents are described as a combination of a chemical
 with its salts and/or esters, the CAS number is given for the parent compound only.
  3 Concentration standards for wastewaters are expressed in mg/L and are based on analysis of composite samples.
  4 All treatment standards expressed as a Technology Code or combination of Technology Codes are explained in detail in 40 CFR 268 42
 Table 1-Technology Codes and Descriptions of Technology-Based Standards.
  5 Except for Metals (EP or TCLP) and Cyanides (Total and Amenable) the nonwastewater treatment standards expressed as a concentration
 were established, in part,  based upon incineration in units operated in accordance with the technical requirements of 40 CFR Part 264 Subpart O
 or Part 265 Subpart O, or based upon combustion in fuel substitution units operating in accordance with applicable technical requirements A fa-
 cility may comply with these treatment standards according to provisions in 40 CFR 268.40(d).  All concentration standards for nonwastewaters
 are based on analysis of grab samples.
   19. In § 268.48(a) the Table is
amended by adding in alphabetical
order the following entries under the
heading organic constituents: (The
footnotes are republished without
change.)

  UNIVERSAL TREATMENT STANDARDS
§268.48

  (a)*  •
Universal treatment standards.
Wastewater
f^/voi standard
Regulated constituent common name h concentration
0 numDsr •
mg/L 2
Nonwastewater
standard
concentration in
mg/Kg3 unless
noted as
"mg/L TCLP"
1,2,3,4,6,7,8-HeptachIorodibenzo-jCnJioxin (1,2,3,4,6,7,8-HpCDD) 	    35822-39-4       0.000035          0.0025
1,2,3,4,6,7,8-Hept'achlorodibenzofuran (1,2,3,4,6,7,8-HpCDF) 	    67562-39—4-       0.000035          0.0025
1,2,3,4,7,8,9-Heptachlorodibenzofuran (1,2,3,6,7,8,9-HpCDF) 	    55673-89-7       0.000035          0.0025
1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (OCDD) 	    3268-87-9       0.000063          0.005
1,2,3,4,6,7,8,9-Octachlorodibenzofuran (OCDF)	   39001-02-0       0.000063          0.005

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 46538
                Federal Register/Vol. 64, No. 164/Wednesday,  August 25,  1999/Proposed  Rules
  * Note: NA means not applicable.
  1 CAS means Chemical Abstract Services. When the waste code and/or regulated constituents are described as a combination of a chemical
with its salts and/or esters, the CAS number is given for the parent compound only.
  2 Concentration standards for wastewaters are expressed in mg/L and are based on analysis of composite samples.
  3 Except for Metals (EP or TCLP) and Cyanides (Total and Amenable) the nonwastewater treatment standards expressed as a concentration
were established, in part, based upon incineration in units operated in accordance with the technical requirements of 40 CFR Part 264, Subpart
O, or Part 265, Subpart O, or based upon combustion in fuel substitution units operating in accordance with applicable technical requirements. A
facility may comply with these treatment standards according to provisions in 40 CFR 268.40(d). All concentration standards for nonwastewaters
are based on analysis of grab samples.
                               *****


            PART 271—REQUIREMENTS FOR AUTHORIZATION OF STATE HAZARDOUS WASTE PROGRAMS

    20. The authority citation for part 271 continues to read as follows:

   Authority: 42 U.S.C. 6905, 6912(a). and 6926.

    21.  Section  271.1(j)  is amended  by adding the  following  entries to Table 1  and Table 2 in chronological order
by date to read as follows.
§ 271.1  Purpose and scope.
»     *     *    *    *
                                           0)*  *  *


          TABLE 1.—REGULATIONS IMPLEMENTING THE HAZARDOUS AND SOLID WASTE AMENDMENTS OF 1984
       Promulgation dale
                                     Title of regulation
Federal Register
   reference
   Effective date
(insert date of  signature of final  Listing   of  Hazardous  Wastes  [insert  Federal
  rule]                           K173, K174, and K175            numbers]
                                                                            Register  page  [insert effective date of final rule]
                TABLE 2.—SELF IMPLEMENTING PROVISIONS OF THE SOLID WASTE AMENDMENTS OF 1984
      Effective date
                                    Self-implementing provision
         RCRA citation
Federal Register reference
(effective date of final rule].
                         Prohibition on land disposal of K173, K174, and K175  3004(g)(4)(C) and 3004(m).  [date of publication of final
                          wastes, and prohibition on land  disposal of radio-                             rule], [FR page num-
                          active  waste  mixed with  K173,  K174, and K175                             bersj.
                          wastes, including soil and debris.
                      PART 302—DESIGNATION, REPORTABLE QUANTITIES, AND NOTIFICATION

    22. The authority citation for part 302 continues to read as follows:
   Authority: 42 U.S.C. 9602, 9603. and 9604: 33 U.S.C. 1321 and 1361.

    23.  In §302.4.  Table 302.4  is amended by adding  the following new entries in alphanumeric  order at the end
of the table to read as follows:

§302.4  Designation of hazardous substances
                    TABLE 302.4—LIST OF HAZARDOUS  SUBSTANCES AND REPORTABLE QUANTITIES
                                 [Note: All Comments/Notes Are Located at the End of This Table]

Hazardous substance
K173* 	 	 , 	
K174f 	 , 	
K175' 	

CASRN




Regulatory synonyms




RQ
*1
*1
*1
Statutory
Codet
4
4
4

RCRA
waste
No.
K173
K174
K175
Fina
Category
X
X
X
RQ
Pounds
(Kg)
1 (0 454)
1 (0.454)
1(0.454)
  t Indicates the statutory sources as defined by 1, 2, 3, and 4 below.

  4— Indicates that the statutory source for designation of this hazardous substance under CERCLA is RCRA Section 3001.
  *1—indicates that the 1-pound RQ is a CERCLA statutory RQ.^

  'See 40 CFR 302.6(b)(1) for application of the mixture rule to this hazardous waste. -

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                 Federal Register/Vol. 64,  No.  164/Wednesday,  August 25,  1999/Proposed  Rules
46539
     24. Section 302.6 is amended by revising paragraph  (b)(l)(iii) introductory text and by adding  entries K173, -K174,
 and K175 to the table in paragraph (b)(l)(iii) in numerical order to read as follows:
 §302.6  Notification requirements.
     (b) * *  *
     (1) * *  *
     (iii) For waste streams  K169, K170, K171, K172.  K173, K174, and K175,  knowledge of the quantity of all of the
 hazardous constituent (s) may be assumed, based on the following maximum observed constituent concentrations identified
 by EPA:
     Waste
                                                        Constituent
                                                                                                             Max ppm
 K173	  2,3,7,8-TCDD	(000000017
                 1,2,3,7,8-PeCDD	00000015
                 1,2,3,4,7,8-HxCDD 	00000012
                 1,2,3,6,7,8-HxCDD	00000091
                 1,2,3,7,8,9-HxCDD	_	      00000092
                 1,2,3,4,6,7,8-HpCDD	.	                       000044
                 OCDD	      '.WQ22
                 2,3,7,8-TCDF	      .QD000045
                 1,2,3,7,8-PeCDF 	JJ000012
                 2,3,4,7,8-PeCDF	      UI000015
                 1,2,3,4,7,8-HxCDF 	                               000042
                 1,2,3,6,7,8-HxCDF	                                 000045
                 1,2,3,7,8,9-HxCDF 	                               000014
                 2,3,4,6,7,8-HxCDF	                                                    'o00027
                 1,2,3,4,6,7,8-HpCDF	                    	0013
                 1,2,3,4,7,8,9-HpCDF	                      	000^
                 OCDF	      'me
                 Chloroform	                                                  y
 K174	  2,3,7,8-TCDD	.'	"	'	(000039
                 1,2,3,7,8-PeCDD 	      .0000108
                 1,2,3,4,7,8-HxCDD	         0000241
                 1,2,3,6,7,8-HxCDD	       000083
                 1,2,3,7,8,9-HxCDD	                      "       000062
                 1,2,3,4,6,7,8-HpCDD	                    	       00123
                 OCDD	;	:	.".      1(029
                 2,3,7,8-TCDF	       GD00145
                 1,2,3,7,8-PeCDF	       0000777
                 2,3,4,7,8-PeCDF	         (H00127
                 1,2,3,4,7,8-HxCDF 	                                             001425
                 1,2,3,6,7,8-HxCDF	  ''..' ""'	oo0281
                 1,2,3,7,8,9-HxCDF 	                                                    00014
                 2,3,4,6,7,8-HxCDF	          	000648
                 1,2,3,4,6,7,8-HpCDF	                                                O2Q7
                 1,2,3,4,7,8,9-HpCDF	0135
                 OCDF	      '33,2
K175	   Mercury 	             9200
[FR Doc. 99-20753 Filed 8-24-99; 8:45 am]
BILLING CODE 6560-50-P

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Correction Notice



  Septembers, 1999

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49052
 Corrections
                                     Federal Register

                                     Vol. 64, No. 174

                                     Thursday, September 9,  1999
This section of the FEDERAL REGISTER
contains editorial corrections of previously
published Presidential, Rule, Proposed Rule,
and Notice documents. These corrections are
prepared by the Office of the Federal
Register. Agency prepared corrections are
Issued as signed documents and appear in
the appropriate document categories
elsewhere in the issue.
Wednesday, August 25, 1999, make the
following correction (s):
  On page 46495, remove the heading
for Table III-4. and the tables designated
as Table III-4A and Table III-4B, and add
Table III-5A and Table Ill-SB as follows:
ENVIRONMENTAL PROTECTION
AGENCY

40 CFR Parts 148,261,264,265,268,
271, and 302

[SWH-FRL-641S-4]

RIN 2050-AD85

Hazardous Waste Management
System; Identification and Listing of
Hazardous Waste; Chlorinated
Aliphatics Production Wastes; Land
Disposal Restrictions for Newly
Identified Wastes; and CERCLA
Hazardous Substance Designation and
Reportable Quantities

Correction
  In proposed rule document 99-20753.
beginning on page 46476, in the issue of

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              Federal Register / Vol. 64, No. 174 / Thursday, September 9, 1999 / Corrections
49053
           Table III-5.  Summary of Excess Lifetime Arsenic Cancer Risks Attributable to
                      Management of EDC/VCM Sludge in An Offsite Landfill
                              Table III-5A. Deterministic Risk Results
Receptor
Fanner
Child of Farmer/Child of Resident
Adult Resident/Gardener/Fisher
HE
3E-05
9E-06
2E-05
CT
9E-07
6E-07
8E-07
High End Parameters
Distance To Receptor Weil and Exposure
Duration
                                  HE = High End; CT = Central Tendency

            Time for Peak concentration to reach receptor is approximately 8800 years (HE), 9600 years (CT)
                              Table Ill-SB. Probabilistic Risk  Results
Receptor
Farmer
Adult Resident/Gardener/Fisher
Child Resident
Age 1-5
Age 6-11
Age 12-18
Farm Child
Age 1-5
Age 6-11
Age 12-1 8
Percentile
50th
2E-08
2E-08
90th
3E-06
3E-06
95th
8E-06
6E-06
97.5th
1E-05
1E-05
100th
3E-04
2E-04

IE-OS
1E-08
9E-09
2E-06
2E-06
IE-06
5E-06
4E-06
3E-06
9E-06
8E-06
6E-06
1E-04
1E-04
9E-05

3E-08
2E-08.
IE-OS
4E-06
3E-06
2E-06
9E-06
6E-06
5E-06
2E-05
1E-05
IE-OS
2E-04
2E-04
1E-04
[FR Doc. C9-20753 Filed 9-8-99; 8:45 am]
BILLING CODE 1505-01-D

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