United States       Solid Waste and
         Environmental Protection   Emergency Response  EPA/530-SW-90-070B
         Agency         (OS-305)       July 1990
&EPA   Report to Congress on
         Special Wastes from
         Mineral Processing
         Summary and Findings

-------

-------
                                      Table of Contents
                                                                                         Page

 1.0     Introduction	                1

 2.0     RCRA 8002(p) Study Factors 		        3

 3.0     Methods, Information Sources and Decision Rationale 	                 4

        3.1    EPA Data Collection Activities	   4
        3.2    Analytical Approach and Methods	   4
        3.3    Decision Rationale	                         g

4.0     Findings  	                    ,*

        4.1   Application of the RCRA 8002(p) Study Factors:  Approach 1  	   11
        4.2   Application of the RCRA 8002(p) Study Factors and Additional
             Considerations: Approach 2	             lg

-------

-------
                                Summary and Findings
 1.0     Introduction

         In October, 1980, the Resource Conservation and Recovery Act (RCRA) was amended by adding
 3001(b)(3)(A)(ii) to  exclude "solid waste from the extraction, beneficiation, and processing of ores  and
 minerals'1 from regulation as hazardous waste under Subtitle C of RCRA, pending completion of a study and
 a Report to Congress required by 8002(f) and (p) and a determination by the EPA Administrator either to
 promulgate regulations under  Subtitle C  or  that such  regulations are  unwarranted  (as  required  by
 3001(b)(3)(C)).  EPA modified its hazardous waste regulations in November 1980 to reflect  this "Mining
 Waste Exclusion," and issued a preliminary, and quite broad, interpretation of the scope of its coverage.  In
 particular, EPA interpreted the exclusion to include  "solid  waste from the exploration, mining, milling,
 smelting and refining of ores and minerals" (45 FR 76618, November 19, 1980).
         In 1984, EPA was sued for failing to submit the Report to Congress and make the required regulatory
 determination by the statutory deadline (Concerned Citizens ofAdamstown v. EPA No. 84-3041, D.D.C, August
 21, 1985).  In responding to this lawsuit, the  Agency explained  that it  planned to propose a narrower
 interpretation of the scope of the Mining Waste Exclusion, so  that it would encompass fewer wastes, and
 proposed to the Court two schedules: one for completing the 8002 studies of extraction and beneficiation
 wastes and submitting the Report to Congress for these wastes, and one for  proposing and promulgating a
 reinterpretation for mineral processing wastes. In so doing, the Agency, in effect, split the wastes that might
 be eligible for exclusion from regulation into two groups: mining (mineral extraction and beneficiation) wastes,
 and mineral processing wastes.  The Court agreed to this approach and established a schedule for the two
 tasks.

        On December 31,1985, EPA published the required Report to Congress on solid wastes from mineral
 extraction  and beneficiation,1 and on July 3, 1986 (51 FR 24496) published a determination that regulation
 of such wastes under Subtitle C of RCRA was not warranted. Since  the determination was made, the Agency
 has been developing a tailored regulatory  approach  for  these materials under  the auspices of RCRA
 Subtitle D. In May, 1988, EPA issued a staff-level approach for regulating  mining wastes (referred to as
 "Strawman") for public comment. More recently, the Agency issued a revised staff-level approach ("Strawman
 II") that incorporates comments  from and responds to issues raised by the states, environmental groups, and
 the regulated community.  The Agency is working to develop a formal proposal of a regulatory program for
 mineral extraction and beneficiation wastes.2
        In keeping with its Court-ordered directive to  reinterpret the Mining ^feste Exclusion for mineral
 processing wastes,  in October,  1985, EPA proposed  to narrow the scope of the Exclusion  for mineral
 processing wastes to include only a few specific waste  streams.   However, the Agency did not specify the
 criteria that it used to identify these materials, or to distinguish them from other wastes that were not eligible
 for the exclusion. In response to this proposal, many companies and industry organizations "nominated" wastes
 that they believed were eligible for the regulatory exemption. Faced with an inability at that time to articulate
    U. S. Environmental Protection Agency, 1985. Report to Congress on Wastes from the Extraction and BeneGciation of Metallic
Ores. Phosphate Rock. Asbestos. Overburden from Uranium Mining, and Oil Shale. EPA/530-SW-85-033, Washington, D.C.
Available from the U.S. Department of Commerce, National Technical Information Service, Springfield, VA.  NTIS Document No
PB88-162631.                                                           re.

   2 The Agency has recently requested comments on Strawman II, including the appropriate scope of the program (i.e., which wastes
should be covered).

-------
      Summary and Findings
 criteria that could be used to distinguish exempt from non-exempt wastes and the approaching Court-ordered
 deadline for final action, EPA withdrew its proposal on October 9, 1986.

        In response to this action, the Agency was sued again.  In July, 1988, the court in Environmental
 Defense Fund v. EPA, 852 F.2d  1316 (D. C. Cir. 1988), cert, denied, 109 S. Ct 1120 (1989) ordered EPA to
 reinterpret  the scope  of the Exclusion for mineral processing wastes according to a new schedule.  In
 particular, EPA was directed by the court to restrict the scope of the Exclusion as it applied  to mineral
 processing wastes to include only large volume, low hazard" wastes. In a series of rulemaking notices, EPA
 has, during the past  two years, established  the  boundaries of the Mining ^feste  Exclusion for mineral
 processing wastes, and has articulated the criteria that were used to define "mineral processing" and  to evaluate
 whether individual wastes are large volume and low hazard and, thus, eligible for the temporary exclusion
 provided by RCRA 3001(b)(3)(A)(ii). This, rulemaking process was completed with the publication of a final
 rule on January 23,1990 (55 FR 2322).3  With the completion of these notices, the Agency established that
 the temporary exemption from  Subtitle C requirements established by the Exclusion for mineral  processing
 wastes and, therefore,  the scope of this report, is limited to 20 mineral processing wastes generated by 91
 facilities located in 29 states, representing 12 mineral commodity sectors. In particular, this report covers the
 following wastes:

            Alumina
                    red and brown muds from bauxite refining
            Chromium (Sodium chromate/dichromate')
                    treated residue from roasting/leaching of chrome ore
            Coal gas                                                                           *
                    gasifier ash from coal gasification
                    process wastewater from coal gasification
            Copper
                    slag from primary processing
                    calcium sulfate wastewater treatment plant sludge from primary
                    processing
                    slag tailings from primary processing
            Elemental phosphorus
                    slag from primary production
            Ferrous metals (iron and carbon steel)
                    iron blast furnace air pollution  control dust/sludge
                    iron blast furnace slag
                    basic oxygen furnace and open hearth furnace  air pollution control
                    dust/sludge
                    basic oxygen furnace and open hearth furnace slag
            Hydrofluoric acid
                    fiuorogypsum
                    process wastewater
              Lead
                    slag from  primary processing

             Magnesium
                     process wastewater from primary magnesium processing by the anhydrous  process
   3 This rulemaking process also included publication of a proposed rule on October 20, 1988 (S3 FR 41288), a proposed rule on
April 17,1989 (54 FR 15316), a final rule on September 1,1989 ( 54 FR 36592), and a proposed rule on September 25, 1989 (54 FR
39298).

-------
                                                                           Summary and Findings   3
                Phosphoric acid
                      phosphogypsum
                      process wastewater
                Titanium tetrachloride
                -     chloride process waste solids
                Zinc
                      slag  from primary processing
 All other solid wastes from  the processing of ores and minerals were removed from the Mining \Vfeste
 Exclusion as of the effective date of the September 1,1989 or January 23, 1990 final rules (March 1,1990, or
 July 23,1990 in non-authorized states), and are subject to regulation as hazardous wastes if they exhibit one
 or more characteristics of  hazardous waste or are otherwise listed as hazardous waste.4
         A summary of the important events in the rulemaking process and of the criteria that have been
 developed by the Agency to identify the 20 special  wastes from mineral processing operations is presented in
 Appendix A to the report  (contained in Volume III).
         Following receipt  and analysis of public comment on this report, the Agency will issue the regulatory
 determination required by RCRA 3001(b)(3)(C) that will either subject one or more of the 20 special mineral
 processing wastes  to  regulation under Subtitle C  as hazardous wastes or conclude that such regulation is
 unwarranted.  Wastes for  which the Exclusion is  retained will continue to be subject to regulation under
 RCRA Subtitle D as solid  wastes. Our assessment of risk in this report has been based on a conservative set
 of risk assumptions.  If additional regulation of these wastes is determined to be necessary, we would make
 such a determination with  this in mind.

 2.0     RCRA 8002(p) Study Factors
         This report addresses the following eight  study  factors required by 8002(p) of RCRA for the 20
 mineral  processing wastes  listed above:


         1.     The sources and volumes of such materials generated per year;
         2.     Present disposal and utilization practices;
         3.     Potential danger to human health and the environment from the disposal and
               reuse of such materials;
         4.     Documented cases in which danger to human health or the environment has
               been proved;
         5.     Alternatives to current disposal methods;
         6.     The costs of such alternatives;
         7.     The impacts of these alternatives on the use of phosphate rock, uranium ore,
               and other natural resources; and
   4 Because the requirements of the September 1,1989 and January 23,1990 final rules were not imposed pursuant to the
Hazardous and Solid Waste Amendments of 1984, they will not be effective in RCRA authorized states until the state program
amendments are effective. Thus, the rules are effective on March 1,1990 and July 23,1990 (for the September 1,1989 and January
23,1990 rules, respectively) only in those states that do not have final authorization to operate their own hazardous waste programs in
lieu of the Federal program. In authorized states, the rules are not applicable until the state revises its program to adopt equivalent
requirements under state law and receives authorization for these new requirements. (Of course, the requirements will be applicable
as state law if the state law is effective prior to authorization.) States that have final authorization must revise their programs to adopt
equivalent standards regulating non-exempt mineral processing wastes that exhibit hazardous characteristics as hazardous by July 1,
1991 if regulatory changes only are necessary, or by July 1, 1992 if statutory changes are necessary. Once EPA approves the revision,
the state requirements become RCRA Subtitle C requirements in that state.

-------
      Summary and Findings
        8.    The current and potential utilization of such materials.


        The Agency's approach in preparing this report was to combine certain study factors for purposes of
analysis and exposition.  The resulting discussions, which are found in individual chapters (in Volume II)
addressing each of the mineral commodity sectors, are organized in seven sections. The first section provides
a brief overview of the industry, including the types of production processes used and the number and location
of operating facilities that generate one or more mineral processing special wastes.  The second section
summarizes information on special waste characteristics, generation, and current management practices (study
factors 1 and 2), while the third section provides a discussion of potential for and documented cases of danger
to human health or the environment (study factors 3 and 4).  The fourth section (as suggested by  8002(p)
of RCRA, independent of the eight study factors) summarizes applicable federal and state regulatory controls.
The fifth section discusses alternative waste management practices and potential utilization of the wastes (study
factors 5 and 8), while the sixth section discusses costs and impacts of alternative practices (study factors 6 and
7). The seventh and final section summarizes and analyzes the  findings of EPA's evaluation of the above study
factors.


3.0    Methods, Information Sources and Decision Rationale
        In preparing this report, EPA has developed facility-specific data and analytical  methods that reflect
the complexity of the issues that are addressed herein. The facilities that generate the special study wastes vary
considerably in the types of production operations and waste management techniques that they employ.
Moreover, to examine in detail the broad array of study factors mandated by RCRA 8002(p), EPA had to
develop approaches and methods that were sufficiently sophisticated to take into account the special nature
of high volume mineral processing wastes. This section briefly outlines the data sources, methods, and decision
rationale that the Agency employed to respond to the study factors.


        3.1       EPA  Data  Collection Activities
        EPA's Office  of Solid Waste conducted a number of data collection activities to supplement and
update previous work.  The focus of most of these efforts was site-specific.  As a consequence, EPA has been
able to compile detailed facility- and sector-specific data bases, which the Agency has used extensively to
prepare this report as well as a series of rulemakings which, as discussed above, have clarified the boundaries
of the Mining Waste Exclusion as it applies  to mineral processing wastes.  The major information-gathering
initiatives are as follows:
             Review of Public Comments
             1989 National Survey of Solid Wastes from Mineral Processing Facilities (SWMPF
              Survey)
             1989 EPA Mineral Processing Waste Sampling  and Analysis
             EPA Damage Case Collection
             EPA Site Visits
             RCRA 3007 Waste Characteristics Data Requests
These activities are described in more detail in Chapter  2 of Volume II, with additional discussion and/or
examples provided in Appendix B, which is contained in Volume III.


        3.2      Analytical Approach and Methods
        This section summarizes EPAs approach for addressing each of the study factors.

-------
                                                                       Summary and Findings    5
         Waste Characteristics, Generation, and Current Management Practices
         To characterize the generation and management of each of the 20 special mineral processing wastes,
 EPA had to identify the facilities that generate the wastes, the production processes used and the products
 produced, the quantity and characteristics of the wastes generated, and the practices that are employed to
 manage them.

         The identification of the facilities that generate one or more of the 20 special wastes was based upon
 prior EPA work, supplemented extensively by information provided by Commodity Specialists with the U.S.
 Bureau of Mines.  The operators of these facilities then were sent a survey questionnaire (SWMPF Survey)
 requesting information on waste generation and management.  Survey responses allowed EPA to finalize its
 list of the active facilities in the mineral processing sectors of concern, and serve as the primary basis of EPA's
 understanding of the current management practices that are applied to special wastes from mineral processing
 operations.

         Information submitted by industry in response to the SWMPF Survey was supplemented with and
 critically evaluated against data obtained from published sources, information collected as part of the damage
 case development process,  and EPA observations made during waste sampling  and  other site visits.  The
 descriptions of waste management practices provided in this report reflect EPA's synthesis of the information
 obtained during all of these information collection activities.


         Potential  and Documented Danger to Human Health  and the  Environment

         Potential Danger to Human Health and the Environment
         EPA conducted  a  facility-specific analysis of the risks associated with each  of the 20 mineral
 processing wastes. The Agency  collected  information on the major factors that influence  risks from  the
 management of the special wastes at each of the 91 facilities that generate the wastes, and analyzed this
 information to develop conclusions on the potential for toxic constituents to be released  from the waste and
 cause human  health and environmental impacts.   In  a  limited number of cases, EPA also  conducted
 quantitative risk modeling to estimate potential danger to human health and the environment.
         EPA employed a three step approach in this risk assessment, using each step as a means of narrowing
 the scope of the analysis to those wastes and facilities that pose the greatest potential risk. First, the Agency
 assessed the intrinsic hazard of the wastes by comparing the concentrations of toxic constituents in the wastes
 and in leachate from the wastes to screening  criteria.5  This step was used to determine  which, if any,
 constituents of the special wastes may pose risks to human health and the environment based on reasonable,
 but conservative exposure assumptions. Second, EPA assessed the potential for toxic constituents from the
 subject wastes to cause damage at the 91 facilities by evaluating the practices currently used to manage the
 wastes and the environmental settings in which the wastes  are managed.  Using facility-specific information
 about special waste management and environmental  setting, EPA then evaluated the potential for toxic or
 radioactive constituents to be released from the specific waste management units and to migrate to potential
 exposure points.  Finally, for  waste stream/environmental settings combinations at  which  risk  potential
 appeared to be the  greatest, EPA performed  quantitative  modeling to estimate the human health and
 environmental risks associated with existing waste management practices.
        In all steps of the analysis, EPA focused on human health and environmental risks associated with
chronic exposure to potential releases of waste constituents to  ground water, surface water, and air.  When
 possible, however, the Agency did evaluate the potential for large episodic releases of waste constituents (e.g.,
 from storm or flood events) to endanger human health or the environment. To analyze risks to human health,
   The focus of the screening criteria is on toricity and radioactivity, in addition to a simple determination of corrosivity. EPA has
sufficient knowledge of the characteristics of the 20 special mineral processing wastes to conclude that none are ignitable or reactive.

-------
       Summary and Findings
 the Agency evaluated the cancer and noncancer risks to maximally exposed individuals at each site. To analvze
 environmental risks, the Agency evaluated the potential for contaminants to migrate from  the waste  id
 adversely affect aquatic organisms. In addition to risks to human health and aquatic life, EPA also evaluated
 the potential for existing waste management practices to reduce the quality of water and air resources by
 considering  the potential  for air and water contamination, irrespective  of the  potential for humans or
 ecological receptors to be exposed to the contamination.

         Documented Cases of Danger to Human Health or the Environment
         Section 8002(p)(4) of RCRA requires that EPA's study of mineral processing wastes examine
 "documented cases in which danger to human health or the environment has been proved."  In order to address
 this requirement,  EPA defined danger to  human health and the environment in the following way.  First,
 danger to human health includes both acute and  chronic effects  associated with  management of mineral
 processing wastes.  Second, danger to the environment includes: (1) impairment of natural  resources; (2)
 ecological effects resulting in impairment of the structure or function of natural ecosystems and habitats; and
 (3) effects on wildlife resulting in impairment to terrestrial or aquatic species.
         The statutory requirement is that EPA examine "proven"  cases of danger to human health or the
 environment  As a result, EPA developed a "test  of proof to be used for determining if documentation
 available on a case proves that danger/damage has occurred. This "test of proof contains three separate tests;
 a case that satisfies one or more of these tests is considered "proven." The tests are as follows:
         1.     Scientific investigation:  Damages are found to exist  as part of the findings of a
               scientific study. Such studies include both extensive  formal investigations supporting
               litigation or a State enforcement action and the results of technical tests (such as
               monitoring of wells). Scientific studies must demonstrate that damages are significant
               in terms of impacts on human health or the environment. For example, information
               on contamination of a drinking water aquifer must indicate that contamination levels
               exceed drinking water standards.
         2.     Administrative ruling:  Damages are found to exist through a formal administrative
               ruling,  such as the conclusions  of  a site report by a field inspector, or through
               existence of an enforcement  action that cited specific health or environmental
               damages.
         3.     Court decision: Damages are found to exist through the ruling of a court or through'
               an out-of-court settlement.
         EPA has taken care in the course of preparing this evaluation to  report only damages  that are
 relevant to the decisions that will be based upon the Report to Congress (i.e., whether regulation of each of
 the special wastes from mineral processing under Subtitle C is appropriate). Consequently, the damage cases
 reponed here are believed to be attributable (at least in part) to the special study wastes, and are believed to
 have resulted from management practices that are currently employed by active facilities in the commodity
 sectors of interest


        Existing Federal and State Waste Management  Controls
        In accordance with the suggestion in RCRA 8002(p), EPA has also examined other applicable federal
and state waste management controls in an effort to minimize duplication.

        Federal Controls
        EPA's objective in this analysis was to identify and evaluate the existing regulatory controls over the
management  of special mineral processing wastes that have been  promulgated by agencies of the federal
government, focusing on programs and requirements established by EPA. This evaluation was performed for

-------
                                                                        Summary and Findings
 two reasons.  First, some states do not have regulatory programs, meaning that federal requirements apply
 directly.  Second,  the  federal government has not delegated authority to states for implementing some
 environmental protection statutes and regulations.
         The  initial phase  of the analysis examined  the  relevant statutes and regulations pertaining to
 hazardous waste, solid  waste, air quality, and water quality as they might apply to the management of the
 mineral processing special wastes, in general.  The second phase of this analysis was to identify and evaluate
 any specific regulations that pertain to any of the 20 special mineral processing wastes.  The final phase of the
 analysis involved contacting Regional EPA staff in those states that do not have federally approved programs
 for implementation of the major environmental statutes, as well as relevant staff within other federal agencies
 and departments, and performing a regulatory analysis of the implementation of all existing federal statutes
 and regulations that pertain specifically to the management of the 20 special mineral processing wastes.  The
 findings of this review are contained within the twelve commodity-specific chapters, while descriptions of the
 major federal statutes and regulations that affect mineral processing wastes management generally are provided
 in Appendix D-l (in Volume III).

         Requirements in Selected States
         EPA's goal in this analysis was to determine the current regulatory stance of states with regard to the
 mineral processing wastes generated by the 12 commodity sectors addressed in this report. The analysis serves
 more generally to help characterize current waste management and disposal practices taking place as a result
 of state regulation.

         The first step in the analysis focused  on reviewing material in a  previous EPA-sponsored study on
 state-level regulation of mining and mineral processing wastes. The  second step of EPA's analysis was to
 perform a more detailed review of individual state statutes and regulations; this review was limited in scope
 to a representative sample (18) of the 29 states containing facilities of interest for further analysis.  While this
 more detailed study addressed, in part, the regulatory status of special mineral processing wastes, EPA found
 that the scope of state programs was not always clear from the state statutory and regulatory language that
 was reviewed. The  final step of EPA's analysis, therefore, consisted of contacting state officials involved with
 the implementation of legal requirements in order to learn how those statutes and regulations are interpreted
 in practice, and to obtain facility-specific implementation information.  The information compiled from these
 contacts was combined with the existing information on statutory and regulatory requirements to produce a
 final implementation analysis, which describes the existing regulatory structure  applicable to the 20 mineral
 processing wastes generated by the twelve commodity sectors considered in this Report to Congress.

        Alternative Management Practices and  Potential Utilization
        Section 8002(p) of the RCRA statute requires that EPA consider alternatives to  current disposal
 methods, as well as the  current and potential utilization of the wastes addressed by the Report to Congress.
 In order to accomplish this,  this  report  identifies  demonstrated alternatives  for waste management and
 utilization. The costs, current  use, potential use, and environmental impact of each alternative are evaluated
 to the extent permitted  by the information available.
        Because the primary purpose of this report is to determine whether the regulation of the special
 mineral processing wastes under Subtitle C is warranted, EPA focused its efforts and the discussion of waste
 management alternatives presented herein on those wastes that potentially may be candidates for Subtitle C
regulation, excluding consideration of the costs and impacts of the various scenarios.
        The focus of this analysis was on conducting a comprehensive computer-assisted literature search, then
evaluating the information obtained thereby. In some instances, more detailed information was solicited from
individual researchers, agencies, and trade associations. Detailed discussion of alternatives is  limited in scope,
however, to those for which information is adequate to assess their technical feasibility (i.e., EPA has not

-------
 8    Summary and Findings
 generally  included  alternatives that are experimental, unproven, or have not seen at least  pilot-scale
 application).

         Cost and Economic Irr   acts
         Section 8002(p) of RCRA requires EPA to analyze "alternatives to current disposal methods" for solid
 wastes generated from the extraction, beneficiation, and processing of ores and minerals.  EPA is also required
 to analyze "the costs of such alternatives."  Section 6  of each commodity-specific chapter (in Volume II)
 discusses the costs and associated economic impacts of alternative waste management practices. The analysis
 of costs and impacts is limited in scope to those waste streams that exhibit one or more characteristics of
 hazardous waste and/or exhibit documented damage or potential risk.
         The focus of the analysis is on the comparative operational and financial consequences of regulating
 these materials under various regulatory schemes. First, cost and impacts are calculated for regulation of these
 wastes under full Subtitle C of RCRA.  Two less stringent regulatory scenarios are also considered, one of
 which reflects the potential for relaxed hazardous waste management controls found at 3004(x)  of RCRA
 ("Subtitle  C-Minus"), while the other is  a hypothetical Subtitle D  program designed to specifically address
 mineral processing wastes ("Subtitle D-Plus").
         The incremental costs associated with alternative regulatory options are compared to several financial
 indicators  at the facility level in order to  determine the relative magnitude of potential impacts.  In addition,
 the Agency has evaluated market conditions facing each affected facility and sector to assess the extent to
 which facilities potentially facing compliance costs would  be able to pass through these costs to various
 product markets or force reductions in the cost of inputs (e.g., ore concentrate, labor).
         In conducting this cost analysis,  EPA has assumed, in most cases, that waste streams are potentially
 hazardous  at only the individual facilities for which data submitted by industry or EPA sampling data indicate
 that the waste exhibits one or more of the four characteristics of a hazardous waste, as defined by 40 CFR Part
 261 Subpart C. When wastes do exhibit a hazardous waste characteristic, it is assumed that the waste(s) would
 be regulated as hazardous waste were it not for the exclusion provided by RCRA 3001(b)(3)(A)(ii), and the
 wastes are examined in the cost analysis accordingly.


         3.3      Decision Rationale
         EPA has developed two alternative approaches  to analyze  the information presented in this report
 regarding each of the 20 special wastes from mineral processing.  Both approaches share a three-step process
 that the  Agency used to evaluate the RCRA 8002(p) study factors by first assessing the need for additional
 regulatory  controls (or absence thereof), then evaluating the options for appropriate requirements that could
 be applied to each individual waste stream for which additional controls might be in order, and, finally,
 estimate the associated costs and impacts. The second approach is distinguished from the first by the addition
 of a fourth step in which the Agency considered additional factors based  on broader Agency goals and
 objectives.  By applying this decision-making framework, consistent decisions regarding the need for additional
 regulatory controls for each of the 20 special  study wastes were achieved.
        In applying the decision criteria, EPA believes that the factors that are most important in establishing
 the regulatory status of the special wastes should be given major emphasis.  Therefore, potential risks posed
and documented damages caused by the wastes, the need for additional regulations, the costs and impacts that
would be associated with more stringent  regulatory controls, and overall Agency objectives are the focus of
the four  steps in the analysis process. The reason for this is that in the  absence of potential risk and/or
documented damages, there is no need for hazardous waste regulation under RCRA Subtitle C (the key issue
in question);  if greater regulatory controls are needed because of significant potential or documented danger,
the costs and impacts of regulatory controls are the critical factors in determining whether a given alternative
would lead to the desired outcome (adequate protection of human health and the environment and continued
operation of the affected industries).

-------
                                                                     Summary and Findings   9
        It should be noted that EPA has done its best to develop and analyze alternatives to current disposal
 methods.  However, these scenarios represent an assessment of how regulatory requirements might be tailored
 to reflect the unusual characteristics of mineral processing wastes, that is, the assumptions made here in
 developing these scenarios may not resemble any actual Subtitle C-Minus or Subtitle D-Plus requirements that
 may be developed by the Agency in the future. As a result, EPA solicits comments on the regulatory scenarios
 that the Agency has used and the appropriateness of the underlying assumptions for the possible  future
 development of regulatory programs under Subtitle D or under Subtitle C using the flexibility provided by
 RCRA 3004(x).
        In considering whether Subtitle C regulation may be warranted or not, EPA is considering how or
 whether to implement the flexibility provided by RCRA 3004(x) to the extent that it can do so and continue
 to ensure human  health and environmental protection.  Specifically, EPA would consider this flexibility in
 establishing  treatment standards for land disposal of these newly identified wastes under 40 CFR Part  268 in
 separate rulemaking under 3004(g)(4) and would develop corrective action requirements on a site-specific
 basis as part of the permitting process.  With respect to the flexibility for minimum technology requirements
 (3004(o) and 3005(j)), EPA solicits comments on how best to implement the flexibility provided by 3004(x),
 such as establishing requirements on  a site-specific basis as pan of the permitting process or development of
 revised standards under Subtitle C regulations.
        The step-wise process that the Agency applied to the available information is outlined below.

        Step 1.    Does management of this waste pose human health/environmental
                    problems?  Might current practices cause problems in the future?
        Critical to the Agency's decision-making process is whether each special waste either has caused or
 may cause human health or  environmental damage. Tb resolve this issue, EPA has posed the following key
 questions:

        1.     Has the waste, as currently managed, caused documented human health impacts
              or  environmental damage?
        2.     Does EPA's analysis  indicate that the waste may pose a significant risk to
              human health or the environment at any of the sites that generate it (or in off-
              site  use), under either current management  practices  or plausible mis-
              management scenarios?
        3.     Does the waste exhibit any of the characteristics of hazardous waste?
 If the  answer to any of these three questions was yes, then EPA concluded that further evaluation was
 necessary. If the answer to all of these questions was no, then the Agency tentatively concluded that regulation
of the waste under RCRA Subtitle C is unwarranted.

        Step 2.    Is more stringent regulation necessary and desirable?
        If the  waste has caused or may potentially cause human health or environmental impacts  under
conservative risk assumptions, then EPA concluded  that an examination of alternative regulatory controls was
appropriate. Given the context and purpose of the present study, the Agency focused on an evaluation  of the
likelihood that such impacts might continue or arise  in the absence of Subtitle C regulation, by posing the
following three questions:
        1.     Are current practices  adequate  to limit contaminant release and associated
              risk?
        2.     What is the likelihood of new facilities opening in the future and generating
              and managing the special waste in a different environmental setting than those
              examined for this report?

-------
 10     Summary and Findings
        3.    Are current federal and state regulatory controls adequate to address the
              management of the waste?
 If current practices or existing regulatory controls are adequate, and if the potential for actual future impacts
 is low (e.g., facilities in remote locations, low probability of new facilities being constructed, low likelihood
 of actual risk), then the Agency may tentatively conclude that regulation of the waste under Subtitle C is
 unwarranted.  Otherwise, further examination of regulatory alternatives is necessary.


        Step 3.    What would be the operational and economic consequences of a
                    decision to regulate  a special waste under Subtitle C?
        If, based upon the previous two steps, EPA believed that a waste might potentially be a candidate for
 regulation under Subtitle C, then the Agency estimated and evaluated the costs and impacts of two regulatory
 alternatives that are based upon Subtitle C, and one alternative that reflects one possible approach that might
 be taken under RCRA Subtitle D ("Subtitle D-Plus").  Two evaluations were performed.  The first focused
 on the magnitude, distribution, and significance of the incremental costs of regulation under full Subtitle C
 as compared to  the Subtitle D-Plus scenario for each potentially affected facility. The second  focused on
 incremental costs and impacts associated with regulation under the Subtitle C-Minus scenario as compared
 to Subtitle D-Plus. The key questions in the Agency's decision-making process for both comparisons were as
 follows:
        1.    Are predicted economic impacts associated with the full Subtitle C (or Subtitle
              C-Minus in the case of the second comparison) scenario significant for any of
              the affected facilities?
        2.    Are these impacts substantially greater than those that would be experienced
              under the Subtitle D-Plus scenario?
        3.    What is the likely extent to which compliance costs could be passed through
              to product markets or input costs could be reduced, i.e., to what extent could
              regulatory cost burdens be shared?
        4.    In the event that costs are significant, could a large proportion of domestic
              capacity or product consumption be affected?
        5.    What effects would hazardous waste regulation have upon the viability of the
              beneficial use or recycling of the special waste?
 In ERA'S judgment, an ability to pass through costs or an absence of significant impacts suggested that Subtitle
 C regulation (or Subtitle C-Minus in the case of the second comparison) might be appropriate for wastes that
 pose significant risk.  In cases in which the Subtitle C (or Subtitle C-Minus) scenario would impose  widespread
 and significant impacts on facilities, result in reductions in domestic capacity or supply, and/or deter the safe
 and beneficial use of the waste, EPA tentatively concluded that regulation under some form of Subtitle D
 program might be more appropriate.


        Step 4.  Additional Considerations
        In this fourth step, which EPA only included in one of the two decision-making approaches, EPA
 considered factors in addition to the 8002(p) study factors that relate to the broader goals and objectives of
 the Agency, including developing and maintaining strong state programs to regulate mining and mineral
 processing wastes.  EPA believes that it may be appropriate to facilitate both d^/elopment and maintenance
of strong state programs and implementation of federal regulations for mineral     essing wastes by regulating
all special wastes from mineral processing under the mining wastes program be  i developed under Subtitle
D of RCRA The relevance of these additional factors, and their impact on EPA's undings, is discussed below.

-------
                                                                     Summary and Findings   11
 4.0    Findings

         Section 3001(b)(3)(C) of RCRA requires that the Agency determine, based on the findings of this
 report, and public hearings and comment, either to promulgate regulations under Subtitle C of RCRA for the
 wastes covered by this study or determine that such regulations are unwarranted. Accordingly, to facilitate
 comment  on this report and  the  subsequent  preparation by the  Agency of the  required "regulatory
 determination," this section presents EPA's findings regarding the 20 special wastes from mineral processing
 based on two separate approaches. These two approaches include:
               Application of the RCRA 8002^1 Study Factors, which discusses the regulatory
               approach (i.e., Subtitle  D or  Subtitle  C)  that  the Agency  tentatively concludes is
               appropriate for each of the 20 mineral processing wastes if the study factors listed in the
               statute alone are considered; and

               Application of the RCRA S8002Cp^ Study Factors and Additional Considerations, which
               discusses (1) additional factors that the Agency believes may be appropriate to consider
               in making a "regulatory determination" and (2) the tentative conclusions that may be
               drawn that include consideration of these additional factors.
        EPA solicits comments on both of these approaches and the tentative conclusions presented below.
 With respect to the decision-making approaches, EPA solicits comments on: (1) what factors  the Agency
 should consider in making the required regulatory determination; (2) what information should be used to
 evaluate these factors; and (3) the relative weight that the factors should be given in developing a regulatory
 determination.


        4.1      Application of the RCRA 8002(p) Study  Factors: Approach 1
        As discussed above, RCRA 8002(p) specifies eight factors that the Agency shall include in the
 analysis performed for this report and suggests that EPA also examine federal and state agency programs to
 avoid duplication of effort. This section presents a summary of the Agency's analysis of these factors and the
 possible conclusions, pending receipt and analysis of public comments, that EPA might make regarding the
 appropriate regulatory status of the 20  mineral processing special wastes covered by this report.  The 20
 mineral processing special wastes are discussed in two groups: (1) wastes that  the Agency might recommend
 regulating under Subtitle D of RCRA; and (2) wastes that the Agency might tentatively consider for regulation
 under Subtitles C or D.


        Wastes EPA Might Tentatively Recommend  to Remain Under RCRA
        Subtitle D

        The available data, the analysis presented in this report, and consideration of the RCRA 8002(p)
study factors suggest that regulation under Subtitle C of RCRA is unwarranted for the following 16 mineral
processing wastes:
             Red and brown muds from bauxite refining;
             Treated residue from roasting/leaching of chrome  ore;
             Gasifier ash from coal gasification;
              Process wastewater from coal gasification;
              Slag from primary copper processing;
              Slag tailings from primary copper processing;
              Slag from elemental phosphorus production;
              Iron blast furnace slag;
              Basic oxygen furnace and  open  hearth furnace slag from carbon steel production;

-------
 12     Summary and Findings
               Air pollution control dust/sludge from iron blast furnaces;
               Air pollution control dust/sludge from basic oxygen furnaces and open hearth furnaces
               from carbon steel production;
               Fluorogypsum from hydrofluoric acid production;
               Process wastewater from primary magnesium processing by the anhydrous process;
               Process wastewater from phosphoric acid production;
               Phosphogypsum from phosphoric acid production; and
               Slag from primary zinc processing.
         In using the  study factors listed in RCRA 8002(p), EPA used the approach described above in
Section 3 to examine:  (1) the potential for and documented danger to human health and the environment; (2)
the need for additional regulations;  and (3) the costs and impacts of Subtitle C regulation.
         EPA did not find significant actual or potential danger associated with the following three wastes,
based on waste characteristics, management practices, and damage case investigations:
               Treated residue from  roasting/leaching of chrome ore;
               Process wastewater from coal gasification; and
               Slag tailings from primary copper processing.
None of these wastes exhibit a characteristic of hazardous waste and no documented damages were identified
as associated with their management.                                                              . .
         The other thirteen wastes listed above were identified as  having some actual or potential hazard
associated with current management practices or plausible mismanagement scenarios, and so were subsequently
evaluated in the second stage of the process.
         In the second stage of the evaluation, EPA identified four wastes that did not exhibit a hazardous
characteristic (with the exception of one sample of copper slag at one facility) but for which documented cases
of adverse environmental impacts that affected surface water were identified at at least one facility:
               Iron blast furnace slag;
              Slag from primary copper processing;
              Basic oxygen furnace and open hearth furnace slag from carbon steel production; and
              Fluorogypsum from hydrofluoric acid production.
In all four cases, however, these surface water releases (one of which occurred via ground water) have been
and/or are being addressed under existing regulatory authorities at the state and/or federal level.  In addition,
the potential for risks associated with management of these wastes at potential new facilities is not likely to
be greater than at the existing facilities.  In the case of fluorogypsum, however, the available data indicate that
the radionuclide content of the waste is such  that under some circumstances  (e.g.,  use of the wastes in
construction) the waste may pose some radiation  risk.  As a result, EPA plans to investigate further the
potential for exposure and associated radiation risk for fluorogypsum and, if appropriate, take steps to limit
such risks under authorities provided by RCRA and other statutes.
         EPA found that two wastes exhibited one or more of the hazardous characteristics, slag from primary
zinc processing and process wastewater from primary  magnesium processing  by the  anhydrous process.
However, each is generated by a single facility, neither of which have documented damages after about 50 and
20 years of operation, respectively. In both cases, market conditions and production processes are such that
construction of additional facilities in the foreseeable future is unlikely. In addition, state regulations are in
effect for the one primary magnesium facility and being revised/strengthened for the primary zinc processing
facility.  EPA plans to investigate further off-site uses of zinc slag for uses that constitute disposal.

-------
                                                                       Summary and Findings    13
         In addition, EPA found that the available data indicate that air pollution control (APC) dust/Sludge
 from iron blast furnaces and from basic oxygen and open hearth furnaces used to make carbon steel exhibit
 the characteristic of EP toxicity at some facilities.  For both types of dust and sludge, relatively few of the
 samples and facilities tested yielded EP-toxic results (for at most two constituents) and the magnitude of the
 exceedances was generally low.  No damage cases were identified for either type of dust/sludge, either for on-
 site or off-site management In addition, several facilities recycle rather than dispose the dust, the facilities
 are generally not in high risk settings, and construction of new facilities is not  likely.
         EPA also found that the potential for hazard associated with two other wastes, red and brown muds
 from bauxite refining and gasifier ash from coal gasification, was comparatively low, except for the radionuclide
 content of the  wastes; in addition, no documented damages attributable to these two wastes were identified.6
 For both of these wastes, however, available data indicate that under some circumstances (e.g., use of the
 wastes in home building materials) the wastes may pose some radiation risk.  As a result, EPA plans to
 investigate further the potential for exposure and associated radiation risk associated with  use of these two
 mineral processing special wastes and, if appropriate, take  steps  to limit such risks under authorities provided
 by statutes other than RCRA

         The radionuclide content, and the associated potential  for radiation risk, is also of concern in three
 other wastes: slag from elemental phosphorus production, and phosphogypsum and process wastewater from
 phosphoric acid production. With respect to slag from elemental phosphorus  production, EPA found that
 average life-time cancer risks range from 4x10"* to IxlO'3 in Soda Springs and Pocatello, Idaho as a result of
 the use of the slag in a wide  range of construction applications.  In other respects, the potential and
 documented danger associated with non-radioactive contaminants contained in elemental phosphorus slag
 appears to be relatively low because: (1) the slag does not exhibit any of the characteristics of hazardous waste;
 and (2) there are no documented damage cases.7  In addition, construction of additional facilities in the
 foreseeable future appears unlikely. EPA plans to use the  authority of RCRA 3001(b)(3)(B)(iii) to  ban the
 use of this  material in  construction  and/or land reclamation  when  the  Agency issues  its regulatory
 determination  for mineral processing wastes.  EPA is soliciting comments on the appropriate regulatory
 language that should be used and how such a ban should be implemented.
        In the case of phosphogypsum, radionuclide hazards associated with air releases from gypsum stacks
 and off-site uses of phosphogypsum are being addressed by the Agency under 40 CFR, Part 61, Subpart R,
 National  Emission   Standards  for  Hazardous Air Pollutants   (NESHAP),  Radon Emissions  from
 Phosphogypsum Stacks (54 FR 51654, December 15,1989; 55 FR 13480, April 10,1990; 55 FR 13482, April
 10, 1990).

        Phosphogypsum and phosphoric acid process wastewater are also of concern because damage case
 information indicates that  both closed and  currently active phosphogypsum  stacks (in which both the
 phosphogypsum and the wastewater are managed) and wastewater cooling ponds have caused and/or are
 causing  ground-water contamination  at  many facilities.   In  addition,   available  data  indicate that
 phosphogypsum tested EP toxic  at one of ten facilities, and process wastewater exhibits the characteristic of
 corrosivity at most facilities and the  EP-toxicity characteristic  at some facilities.   Current regulations are
 apparently not  adequate to  prevent contamination (although this situation may change as state regulatory
 programs improve), so the potential costs of regulation under Subtitle C were examined in the third stage of
 the evaluation.  EPA estimated that the incremental annualized cost of either full Subtitle C regulation or the
 Subtitle C-Minus scenario for phosphogypsum and process wastewater, as compared to the Subtitle  D-Plus
 scenario developed for cost estimating purposes, could exceed $500 million and $50 million respectively, and
 could significantly affect several  facilities. At facilities that EPA estimates could be  significantly affected by
 costs associated with the Subtitle C or Subtitle C-Minus scenarios, the estimated costs of the Subtitle D-Plus
   ' Ground-water contamination at the Dakota Gasification facility in North Dakota was identified, but the source of the
contamination appears to be wastes other than the gasifier ash.

    Ground-water contamination has been identified at one site, but it appears that wastewater was the source rather than slag.

-------
 14    Summary and Findings
 scenario, expressed as a percent of the value of shipments, are substantially less at seven facilities.  The
 estimated impacts associated with Subtitle C or C-Minus regulation at these facilities would be expected to
 be significant, and it is unlikely that these facilities could pass along their higher costs.  EPA considered the
 combined costs of Subtitle C requirements for phosphogypsum and process wastewater because: (1) these two
 wastes are typically co-managed; and (2) the compliance costs associated with both wastes would apply to each
 facility.  EPA is aware, however, that only a portion of the  total process wastewater flow is typically co-
 managed with the phosphogypsum. The Agency may investigate the feasibility of separate management of
 these wastes, as well as separating various wastewater streams in the context of this decisionmaking and the
 development of the mining waste program under Subtitle D.
         In any case, however, EPA is concerned that under  some circumstances  process wastewater  from
 phosphoric acid may pose some radiation risk that would not be addressed by the NESHAP regulation noted
 above.  As a result, EPA plans to investigate further the potential for exposure and associated radiation risk
 associated with this waste and, if appropriate, take steps to limit such risks under authorities provided by
 RCRA and other statutes.


         Wastes EPA Might Tentatively Consider for Regulation
         Under  RCRA Subtitles C or D
         For the remaining four wastes (calcium sulfate wastewater treatment plant sludge from primary copper
 processing, slag from primary lead  processing, process wastewater from  hydrofluoric acid production, and
 chloride process  waste solids from titanium  tetrachloride production), EPA proceeded to evaluate the
 estimated incremental compliance costs and associated impacts in Step 3 of the analysis in two ways.  First,
 EPA examined the estimated costs of regulation under Subtitle  D (using the "D-Plus" scenario) relative to the
 estimated costs of full Subtitle C regulation (Approach 1A).  Second, EPA examined the estimated cost of
 Subtitle D-Plus regulation relative to the cost of regulation under a Subtitle C scenario that utilizes flexibility
 provided by RCRA 3004(x) (Approach IB).  These two analyses are discussed below along with the results
 of analysis Steps 1 and 2 for each of the wastes.  As already indicated, the Subtitle C-Minus and Subtitle D-
 Plus scenarios are based on the  Agency's preliminary assessment of how regulatory requirements might be
 tailored for mineral processing wastes.  Because of this, the Agency is unsure whether the cost/impacts in these
 comparisons are fully appropriate and specifically requests comments on them. The fact that a hypothetical
 Subtitle D-Plus scenario was used for comparison does not mean that any or all of these wastes will necessarily
 be proposed for further regulation.

         Comparison of Subtitle D-Plus and Full Subtitle C (Approach  1A)
         In applying Steps 1 and 2 of the analysis process, EPA found that each of these four special wastes
 have posed or may pose a danger to health or the environment. Available data indicate that all four of the
 wastes exhibit one or more of the  characteristics of hazardous wastes.  All of the  wastes except process
 wastewater from hydrofluoric acid production exhibit the characteristic of EP toxicity  at at least one facility.
 Process wastewater from hydrofluoric acid production is corrosive at all  facilities where it  is generated.
 Documented damages associated with current lead slag management practices were identified and the potential
 for damages exists for the other wastes as well. Ground-water contamination that may in part be attributable
 to calcium sulfate sludge from primary copper processing and chloride process waste solids from titanium
 tetrachloride production was identified at at least one facility that generates one of these wastes.8
        In addition, the Agency is not confident that current practices and regulations are adequate to prevent
 further danger to  health or the environment from these four wastes. Specific reasons are as follows:
   8 Attribution of the observed ground-water contamination at these sites was not possible due to co-management of the special
wastes with other wastes, the close proximity of other waste management units, and/or a long history of production and waste
management activities at the site.

-------
                                                                       Summary and Findings    15
              Current management practices  for hydrofluoric acid process wastewater have  not
               prevented release at one of the currently active facilities.  There is a potential for
               development of additional domestic hydrofluoric acid production capacity, and the
               corresponding construction of new facilities.  New facilities may be located in sensitive
               environmental settings given that the principal feedstock  (acid-grade fluorspar) is
               generally imported and facility locations with ready access to water transportation are
               most likely.

              In the case of calcium sulfate wastewater treatment plant sludge from primary  copper
               processing, applicable solid waste regulations are limited in states where it is currently
               generated and generation of this waste at additional facilities appears likely.9 At least
               some of these additional facilities are in environmental settings that may have a  greater
               potential for risk than the facilities where the waste is currently generated. Ground-
               water contamination at one facility may be due at least in part to disposal of the  sludge.

              Current management practices contributing to documented damages associated with lead
               slag are not  adequately addressed by current regulations.

              Chloride process waste solids from titanium tetrachloride production are generated by
               facilities in eight states, some of which have relatively few solid waste regulations that
               are applicable to the management of this waste.  Construction of several new facilities
               is expected and these facilities may be located in sensitive environmental settings given
               that the principal feedstock is generally imported and facility locations with ready access
               to water transportation are most likely. In addition, EPA is concerned that under some
               circumstances, chloride process waste solids from titanium tetrachloride production may
               pose some radiation risk. As a result, EPA plans to investigate further the potential for
               exposure  and associated radiation risk associated with this waste and, if appropriate,
               take steps to limit such risks under authorities provided by RCRA and other statutes.

        To conduct Step 3 of the analysis process under Approach 1A, EPA estimated the cost of regulating
each of these wastes under full Subtitle C requirements. The Agency then compared the costs for full Subtitle
C regulation to the estimated costs that might result from regulation under Subtitle D requirements  similar
to those being developed for mining wastes ("Subtitle D-Plus").  For three of the four wastes (calcium sulfate
wastewater treatment plant  sludge from primary copper  processing, slag from primary lead processing, and
chloride process waste solids from titanium tetrachloride production), the estimated costs for full Subtitle C
regulation would be significantly larger and the associated impacts would be  more significant at nearly all
facilities than the estimated costs of regulation under the Subtitle D-Plus scenario.  Using this approach, EPA
would tentatively conclude that regulation of these three wastes under Subtitle C is not warranted.

        For process wastewater from hydrofluoric acid production, EPA found that the estimated compliance
costs for regulation under full Subtitle C and regulation under the Subtitle D-Plus scenario were comparable
and that the likely economic impacts were not expected to be significant.  Using this approach to the cost
analysis,  EPA would tentatively conclude that  process wastewater from hydrofluoric acid production may
warrant regulation under Subtitle C


        Comparison of Subtitle D-Plus and Subtitle C-M/nus (Approach  1B)
        Under Approach IB to conducting Step 3, EPA estimated the  cost of managing these four wastes
under  a Subtitle  C scenario that utilizes flexibility  provided by RCRA 3004(x)  (Subtitle C-Minus).  The
Agency then compared the costs for Subtitle C-Minus regulation (rather than full Subtitle C regulation, as in
Approach 1A) to the estimated  costs that might result from regulation under Subtitle D requirements  similar
   9 Additional facilities where the calcium sulfate wastewater treatment sludge may be generated include both existing copper
smelting/refining facilities that do not currently generate the waste and potential new smelting/refining facilities, including a facility on
the Gulf Coast of Texas.

-------
  16     Summary and Findings
  to those being developed for mining wastes (Subtitle D-Plus). EPA found that the estimated costs for the
  Subtitle C-Minus and Subtitle D-Plus scenarios are similar for nearly all facilities.


         4.2     Application of the RCRA 8002(p)  Study  Factors and  Additional
                  Considerations:  Approach 2
         Section  8002(p) of RCRA and the decision in Environmental Defense Fund v. EPA, 852 F.2d 1309
  (D.C. Cir. 1988) make it clear that the Agency may and should consider the specific factors of 8002(p)(l)-(8)
  in making its decision regarding the appropriate regulatory status of special wastes  from mineral processing.
  In addition, the Agency believes that it may be appropriate to consider other factors relating to the broader
  goals and objectives of the Agency, such as developing and'maintaining strong state mining and mineral
  processing waste regulatory programs and facilitating implementation of federal programs (see Step 4 of the
  discussion of the decision rationale in Section 3.3 above).
         The analysis of the 8002(p) study factors presented above indicates that management of one, and
  perhaps as many as four, mineral processing special wastes may be appropriate for regulation under Subtitle
  C if only the study factors are considered, primarily because: (1) they have or could  pose a significant risk to
  human  health and  the environment under current management  practices  or plausible mismanagement
 scenarios; and (2) the costs and impacts of regulation under full Subtitle C (for one waste) or Subtitle C-Minus
  (for three additional wastes) are estimated to be comparable  to the  costs associated with regulation under a
 Subtitle D-Plus program.  In the case of process wastewater from hydrofluoric acid production, the estimated
 costs for the various scenarios are similar in large part because EPA has projected that requirements that
 would be protective of human health and the environment under Subtitle C-Minus, and under full Subtitle
 C as well, might be similar to those that may be required under a Subtitle D-Plus program.  Because of the
 potential similarity between Subtitle  C-Minus and Subtitle D-Plus requirements, as well as broader Agency
 objectives, EPA believes that it may be appropriate to include consideration of the additional factors of state
 program development for mining and mineral processing waste streams, including federal program oversight,
 in order better to distinguish between these two regulatory scenarios.
         Many states have recently or are currently expanding  the scope and requirements of their regulatory
 programs as they apply to mineral processing wastes.  For example,  Florida has recently developed a policy
 that requires additional controls, such as liners, for new or expanded phosphogypsum stacks and is developing
 proposed regulations to update this policy and expand its scope to include phosphoric acid process wastewater.
 Missouri passed the Metallic Minerals >\aste Management Act in 1989, and implementing regulations are
 being  developed, which require permits,  closure plans, maintenance  plans, and  provisions  for financial
 assurance. Pennsylvania has proposed Residual Wiste Regulations that, if promulgated, would require permits
 with provisions for liners,  leachate collection systems, monitoring wells, and disposal of leachate for special
 wastes from iron and steel production and zinc slag (as well as other wastes). Similarly, Delaware, Ohio, and
 Tennessee have all recently developed revised  solid waste regulations that will  increase the stringency of
 requirements for  management of special wastes. Some other states, such as Indiana and Kentucky, already
 have programs that specify management standards for mineral processing wastes.
        In addition, some of these and many other states are currently working with EPA in the development
 of a regulatory program for mining wastes.  This program is designed to be site-specific, risk based, and
 comprehensive. It also is being targeted to address the characteristics of mining wastes and site conditions
 at mining sites.

        EPA believes that it may be appropriate to facilitate  both development and maintenance of strong
 state programs and implementation of any federal regulations that may be necessary for mineral processing
 wastes by regulating all special wastes from mineral processing  under  Subtitle D of RCRA. Some mining and
 mineral processing wastes may be excluded from any further federal  regulation under RCRA.
        In light of these considerations, the results of Approach 2 indicate that it may be appropriate for the
waste streams identified above for potential Subtitle C (full C or C-Minus) regulation not to be subject to

-------
                                                                     Summary and Findings    17
hazardous waste management standards, but instead to be retained within the Mining Waste Exclusion for
mineral processing wastes. If such a finding is appropriate, EPA believes that it would need to be conditioned
on the premise that major steps be taken to take near term actions to control releases from the facilities
producing these waste streams. Some corrective measures are already being taken under a variety of Agency
authorities (i.e., RCRA, Superfund, CWA) and more can and will be undertaken. EPA believes that the states
must act to address the most immediate problems posed by these wastes, as well as any of the other mineral
processing special wastes that have been found in this report to pose significant actual or potential hazard to
human health or the environment.  To assist in  this effort, EPA would provide technical and other resource
support to the involved states to improve their programs.  If near term actions did not result in adequate
control  of such wastes, EPA would then take action to reconsider its regulatory determination and could
designate certain waste streams as Subtitle C hazardous wastes.

-------

-------