[Federal Register Volume 64, Number 33 (Friday, February 19, 1999)]
[Proposed Rules]
[Pages 8278-8288]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-4160]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR PART 261

[SW-FRL-6304-4]


Hazardous Waste Management System; Identification and Listing of 
Hazardous Waste; Proposed Exclusion

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule and request for comment.

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SUMMARY: The EPA is proposing to grant a petition submitted by 
Occidental Chemical Corporation (Occidental Chemical), to exclude (or 
delist) a certain solid waste generated at its Deer Park, Texas, 
facility from the lists of hazardous wastes contained in 40 CFR 261.24, 
261.31, and 261.32, (hereinafter all sectional references are to 40 CFR 
unless otherwise indicated). This petition was submitted under 
Sec. 260.20, which allows any person to petition the Administrator to 
modify or revoke any provision of Secs. 260 through 266, 268 and 273, 
and Sec. 260.22(a), which specifically provides generators the 
opportunity to petition the Administrator to exclude a waste on a 
``generator specific'' basis from the hazardous waste lists. This 
proposed decision is based on an evaluation of waste-specific 
information provided by the petitioner. If this proposed decision is 
finalized, the petitioned waste will be conditionally excluded from the 
requirements of hazardous waste regulations under the Resource 
Conservation and Recovery Act (RCRA).
    The EPA is also proposing the use of a fate and transport model to 
evaluate the potential impact of the petitioned waste on human health 
and the environment, based on the waste-specific information provided 
by the petitioner. This model has been used in evaluating the petition 
to predict the concentration of hazardous constituents that may be 
released from the petitioned waste, once it is disposed.

DATES: The EPA is requesting public comments on this proposed decision 
and on the applicability of the fate and transport model used to 
evaluate the petition. Comments will be accepted until April 5, 1999. 
Comments postmarked after the close of the comment period will be 
stamped ``late,'' and will not be considered in formulating a final 
decision.
    Any person may request a hearing on this proposed decision by 
filing a request with Acting Director, Robert E. Hannesschlager, 
Multimedia Planning and Permitting Division, whose address appears 
below, by March 8, 1999. The request must contain the information 
prescribed in Sec. 260.20(d).

ADDRESSES: Send three copies of your comments to EPA. Two copies should 
be sent to the William Gallagher, Delisting Section, Multimedia 
Planning and Permitting Division (6PD-O), Environmental Protection 
Agency, 1445 Ross Avenue, Dallas, Texas 75202. A third copy should be 
sent to the Texas Natural Resource Conservation Commission, 12100 Park 
35 Circle, Austin, Texas 78753. Identify your comments at the top with 
this regulatory docket number: ``F-97-TXDEL-OCCDEERPK.''
    Requests for a hearing should be addressed to the Acting Director, 
Robert E. Hannesschlager, Multimedia Planning and Permitting Division 
(6PD), Environmental Protection Agency, 1445 Ross Avenue, Dallas, Texas 
75202.
    The RCRA regulatory docket for this proposed rule is located at the 
Environmental Protection Agency Region 6, 1445 Ross Avenue, Dallas, 
Texas 75202 and is available for viewing in the EPA Freedom of 
Information Act Review Room on the 7th Floor from 9:00 a.m. to 4:00 
p.m., Monday through

[[Page 8279]]

Friday, excluding Federal holidays. Call (214) 665-6444 for 
appointments. The public may copy material from any regulatory docket 
at no cost for the first 100 pages, and at fifteen cents per page for 
additional copies.

FOR FURTHER INFORMATION CONTACT: For technical information concerning 
this notice, contact Jon Rinehart, Multimedia Planning and Permitting 
Division, Environmental Protection Agency, Region 6, 1445 Ross Avenue, 
Dallas, TX 75202, (214) 665-6789.

SUPPLEMENTARY INFORMATION:

I. Background

A. Authority

    On January 16, 1981, as part of its final and interim final 
regulations implementing Section 3001 of RCRA, EPA published an amended 
list of hazardous wastes from non-specific and specific sources. This 
list has been amended several times, and is published in Secs. 261.31 
and 261.32. These wastes are listed as hazardous because they typically 
and frequently exhibit one or more of the characteristics of hazardous 
wastes identified in subpart C of part 261 (i.e., ignitability, 
corrosivity, reactivity, and toxicity) or meet the criteria for listing 
contained in Secs. 261.11(a)(2) or (a)(3).
    Individual waste streams may vary however, depending on raw 
materials, industrial processes, and other factors. Thus, while a waste 
that is described in these regulations generally is hazardous, a 
specific waste from an individual facility meeting the listing 
description may not be. For this reason, Secs. 260.20 and 260.22 
provide an exclusion procedure, allowing persons to demonstrate that a 
specific waste from a particular generating facility should not be 
regulated as a hazardous waste.
    To have their wastes excluded, petitioners must show that wastes 
generated at their facilities do not meet any of the criteria for which 
the wastes were listed. See Sec. 260.22(a) and the background documents 
for the listed wastes. In addition, the Hazardous and Solid Waste 
Amendments (HSWA) of 1984 require the EPA to consider any factors 
(including additional constituents) other than those for which the 
waste was listed, if there is a reasonable basis to believe that such 
additional factors could cause the waste to be hazardous. Accordingly, 
a petitioner also must demonstrate that the waste does not exhibit any 
of the hazardous waste characteristics (i.e., ignitability, reactivity, 
corrosivity, and toxicity), and must present sufficient information for 
the EPA to determine whether the waste contains any other toxicants at 
hazardous levels. See Sec. 260.22(a), 42 U.S.C. Sec. 6921(f), and the 
background documents for the listed wastes. Although wastes which are 
``delisted'' (i.e., excluded) have been evaluated to determine whether 
or not they exhibit any of the characteristics of hazardous waste, 
generators remain obligated under RCRA to determine whether or not 
their waste remains nonhazardous based on the hazardous waste 
characteristics.
    In addition, mixtures containing listed hazardous wastes are also 
considered hazardous wastes and wastes derived from the treatment, 
storage, or disposal of listed hazardous waste. See 
Secs. 261.3(a)(2)(iv) and (c)(2)(I), referred to as the ``mixture'' and 
``derived-from'' rules, respectively. Such wastes are also eligible for 
exclusion and remain hazardous wastes until excluded. On December 6, 
1991, the U.S. Court of Appeals for the District of Columbia vacated 
the ``mixture/derived from'' rules and remanded them to the EPA on 
procedural grounds. See Shell Oil Co. v. EPA., 950 F.2d 741 (D.C. Cir. 
1991). On March 3, 1992, EPA reinstated the mixture and derived-from 
rules, and solicited comments on other ways to regulate waste mixtures 
and residues (57 FR 7628). These rules became final on October 30, 1992 
(57 FR 49278). These references should be consulted for more 
information regarding mixtures derived from wastes.

B. Approach Used to Evaluate This Petition

    Occidental Chemical's petition requests a delisting for listed 
hazardous waste. In making the initial delisting determination, the EPA 
evaluated the petitioned waste against the listing criteria and factors 
cited in Secs. 261.11(a)(2) and (a)(3). Based on this review, the EPA 
agreed with the petitioner that the waste is nonhazardous with respect 
to the original listing criteria. (If the EPA had found, based on this 
review, that the waste remained hazardous based on the factors for 
which the waste was originally listed, EPA would have proposed to deny 
the petition.) The EPA then evaluated the waste with respect to other 
factors or criteria to assess whether there is a reasonable basis to 
believe that such additional factors could cause the waste to be 
hazardous. The EPA considered whether the waste is acutely toxic, and 
considered the toxicity of the constituents, the concentration of the 
constituents in the waste, their tendency to migrate and to 
bioaccumulate, their persistence in the environment once released from 
the waste, plausible and specific types of management of the petitioned 
waste, the quantity of waste generated, and waste variability.
    For this delisting determination, the EPA used such information 
gathered to identify plausible exposure routes (i.e., ground water, 
surface water, air) for hazardous constituents present in the 
petitioned waste. The EPA determined that disposal in a Subtitle D 
(solid, nonhazardous waste) landfill is the most reasonable, worse-case 
disposal scenario for Occidental Chemical's petitioned waste, and that 
the major exposure route of concern would be ingestion of contaminated 
ground water. Therefore, the EPA used a particular fate and transport 
model, the EPA Composite Model for Landfills (EPACML), to predict the 
maximum allowable concentrations of hazardous constituents that may be 
released from the petitioned waste after disposal and to determine the 
potential impact of the disposal of Occidental Chemical's petitioned 
waste on human health and the environment. Specifically, the EPA used 
the maximum estimated waste volumes and the maximum reported extract 
concentrations as inputs to estimate the constituent concentrations in 
the ground water at a hypothetical receptor well downgradient from the 
disposal site. The calculated receptor well concentrations (referred to 
as compliance-point concentrations) were then compared directly to the 
health-based levels at an assumed risk of 10-6 used in 
delisting decision-making for the hazardous constituents of concern.
    The EPA believes that this fate and transport model represents a 
reasonable worse-case scenario for disposal of the petitioned waste in 
a landfill, and that a reasonable worse-case scenario is appropriate 
when evaluating whether a waste should be relieved of the protective 
management constraints of RCRA Subtitle C. The use of a reasonable 
worse-case scenario results in conservative values for the compliance-
point concentrations and gives a high degree of confidence that the 
waste, once removed from hazardous waste regulation, will not pose a 
threat to human health or the environment. In most cases, because 
(unless conditionally delisted), a delisted waste is no longer subject 
to hazardous waste control, the EPA is generally unable to predict, and 
does not presently control, how a waste will be managed after 
delisting. Therefore, EPA currently believes that it is inappropriate 
to consider extensive site-specific factors when applying the fate and 
transport model.
    The EPA also considers the applicability of ground water

[[Page 8280]]

monitoring data during the evaluation of delisting petitions. In this 
case, the EPA determined that it would be inappropriate to request 
ground water monitoring data. Specifically, Occidental Chemical 
currently disposes of the petitioned waste (Rockbox Residue) generated 
at its facility in an off-site RCRA hazardous waste landfill (which is 
not owned/operated by Occidental Chemical). This landfill did not begin 
accepting this petitioned waste generated by the Occidental Chemical 
facility until 1991. This petitioned waste comprises a small fraction 
of the total waste managed in the unit. Therefore, the EPA, believes 
that any ground water monitoring data from the landfill would not be 
meaningful for an evaluation of the specific effect of this petitioned 
waste on ground water. Finally, there are presently no data from ground 
water monitoring wells available, therefore there is no data to 
evaluate.
    From the evaluation of Occidental Chemical's delisting petition, a 
list of constituents was developed for the verification testing 
conditions. Proposed maximum allowable leachable concentrations for 
these constituents were derived by back-calculating from the delisting 
health-based levels through the proposed fate and transport model for a 
landfill management scenario. These concentrations (i.e., delisting 
levels) are part of the proposed verification testing conditions of the 
exclusion.
    Similar to other facilities seeking exclusions, Occidental 
Chemical's exclusion (if granted) would be contingent upon the facility 
conducting analytical testing of representative samples of the 
petitioned waste at Deer Park. This testing would be necessary to 
verify that the treatment system is operating as demonstrated in the 
petition submitted on September 19, 1997. Specifically, the 
verification testing requirements would be implemented to demonstrate 
that the processing facility will generate nonhazardous waste (i.e., 
waste that meet the EPA's verification testing conditions). The EPA's 
proposed decision to delist waste from Occidental Chemical's facility 
is based on the information submitted in support of today's rule (i.e., 
description of the wastewater treatment system and analytical data from 
the Deer Park facility).
    Finally, the HSWA specifically requires the EPA to provide notice 
and an opportunity for comment before granting or denying a final 
exclusion. Thus, a final decision will not be made until all timely 
public comments (including those at public hearings, if any) on today's 
proposal are addressed.

II. Disposition of Delisting Petition

    Occidental Chemical Corporation, Deer Park, Texas 77536.

A. Petition for Exclusion

    Occidental Chemical Corporation, located in Deer Park, Texas, 
petitioned the EPA for exclusion for 238 cubic yards of Rockbox 
Residue, per calendar year resulting from its hazardous waste treatment 
process. The resulting waste is presently listed, in accordance with 
Sec. 261.3(c)(2)(I) (i.e., the derived from rule), as EPA Hazardous 
Waste No. K017, K019, and K020. The listed constituents of concern for 
these waste codes are listed in Table 1.

    Table 1--Hazardous Waste Codes Associated With Wastewater Streams
------------------------------------------------------------------------
       Waste code               Basis for characteristics/listing
------------------------------------------------------------------------
K019/K020..............  Ethylene dichloride, 1,1,1-trichloroethane,
                          1,1,2-trichloroethane, 1,1,1,2-
                          tetrachloroethane, 1,1,2,2-tetrachloroethane,
                          trichloroethylene, tetrachloroethylene, carbon
                          tetrachloride, chloroform, vinyl chloride,
                          vinylidene chloride.
K017...................  Epichlorohydrin, chloroethers,
                          trichloropropane, dichloropropanols.
------------------------------------------------------------------------

    Occidental Chemical petitioned to exclude the Rockbox Residue, 
treatment residues because it does not believe that the petitioned 
waste meet the criteria for which it was listed. Occidental Chemical 
further believes that the waste is not hazardous for any other reason 
(i.e., there are no additional constituents or factors that could cause 
the wastes to be hazardous). Review of this petition included 
consideration of the original listing criteria, as well as the 
additional factors required by the HSWA. See Sec. 222 of HSWA, 42 USC 
Sec. 6921(f), and 40 CFR Sec. 260.22(d) (2)-(4). Today's proposal to 
grant this petition for delisting is the result of the EPA's evaluation 
of Occidental Chemical's petition.

B. Background

    On September 19, 1997, Occidental Chemical petitioned the EPA to 
exclude from the lists of hazardous waste contained in Secs. 261.31 and 
261.32, an annual volume of Rockbox Residue, which are generated as a 
result of the treatment of offgases from onsite incinerators. 
Specifically, in its petition, Occidental Chemical requested that the 
EPA grant a standard exclusion for 238 cubic yards of Rockbox Residue, 
generated per calendar year.
    In support of its petition, Occidental Chemical submitted: (1) 
Descriptions of its wastewater treatment processes and the incineration 
activities associated with petitioned wastes; (2) results of the total 
constituent list for 40 CFR part 264 Appendix IX volatiles, 
semivolatiles, and metals except for pesticides, herbicides, and PCBs; 
(3) results of the constituent list for Appendix IX on Toxicity 
Characteristic Leaching Procedure (TCLP) extract for volatiles, 
semivolatiles, and metals; (4) results for reactive sulfide, (5) 
results for reactive cyanide; (6) results for pH; (7) results of 
ignitability; (8) results of the total basis for dioxin and furan; and 
(9) results of dioxin and furan TCLP extract.
    Occidental Chemical is an active plant that produces ethylene 
dichloride (EDC), and vinyl chloride monomer (VCM). The plant utilizes 
chlorine, ethylene, and oxygen as feedstock and utilizes two permitted, 
onsite RCRA incinerators to burn process vent gases, intermediate 
wastes generated during the production of EDC and VCM (K019, K020) and 
epichlorohydrin heavy ends (K017). These two incinerators have been in 
continuous operation since 1987. Occidental Chemical has previously 
classified one waste stream (Rockbox Residue) generated from the 
treatment of the offgas from the incinerators as hazardous based on the 
``derived from'' rule in Sec. 261.3(c)(2)(i).
    The combustion products from the incinerators contain hydrochloric 
acid (HCl). Incinerator offgases are treated in the Incinerator Offgas 
Treatment System. In this system, the emissions are passed through 
absorption columns, dehumidifier columns, and caustic scrubbers to 
remove the HCl. Blowdown water from the dehumidifier columns and 
caustic scrubber columns are routed to the Rockbox Tank (the Rockbox) 
as the first step in neutralizing the HCl. Excess HCl from the aqueous 
HCl storage tanks is commingled with the blowdown water and routed to 
the Rockbox. The influent to Rockbox normally contains 2 to 3 percent 
HCl. At times when excess HCl is not produced, the influent to the 
Rockbox is

[[Page 8281]]

predominantly blowdown from the dehumidifier and caustic scrubber 
columns.
    The Rockbox contains crushed limestone with small amounts of inert 
materials (silica oxide). These inert materials accumulate in the 
bottom of the Rockbox as the crushed limestone is utilized in the 
neutralization process. The accumulation of inert materials is the 
Rockbox Residue. The Rockbox Residue is a ``third generation'' waste 
since it is the residue of treating wastewater used to quench gaseous 
emissions from the incineration of listed wastes.
    The pH of the effluent leaving the Rockbox is between 1 and 4. The 
effluent is passed through a primary pH adjustment tank where air is 
released into the water to remove carbon dioxide. Additionally, sodium 
hydroxide may be added to this tank. Mixing with air minimizes the 
formation of calcium carbonate precipitate upon introduction of caustic 
soda. The effluent is then passed through the secondary pH adjustment 
tank where caustic soda (sodium hydroxide) is added to raise the pH of 
the water to a pH between 7 and 9. The stream, consisting of water and 
calcium carbonate precipitant in suspension, flows through a clarifier 
where the sludge is settled out. The aqueous effluent from the 
clarifier tank is the Caustic Neutralized Wastewater.
    Rockbox Residue is generated on a batch basis every one to two 
years. For the past two years (1995 and 1996), the Rockbox Residue was 
generated annually. This is probably due to a higher than average 
concentration of inerts in the limestone purchased for the Rockbox. The 
Rockbox Residue is disposed of in an offsite permitted hazardous waste 
landfill.
    Occidental Chemical developed a list of constituents of concern 
from comparing a list of all raw materials used in the plant that could 
potentially appear in the petitioned waste with those found in 40 CFR 
Appendix IX Part 264, as well as dioxins and furans. The EPA has 
included the dioxins and furans to the list, due to the incineration of 
chlorinated compounds. Using the list of constituents of concern, 
Occidental analyzed the four composite samples for the total 
concentrations (i.e., mass of a particular constituent per mass of 
waste) of the volatiles and semivolatiles, and metals from Appendix IX. 
These four samples were also analyzed to determine whether the waste 
exhibited ignitable, corrosive, or reactive properties as defined under 
40 CFR Secs. 261.21, 261.22, and 261.23, including analysis for total 
constituent concentrations of cyanide, sulfide, reactive cyanide, and 
reactive sulfide. These four samples were also analyzed for Toxicity 
Characteristic Leaching Procedure (TCLP) concentrations (i.e., mass of 
a particular constituent per unit volume of extract) of all the 
volatiles, semivolatiles, and metals on the Appendix IX list. This list 
was developed based on the availability of test methods and process 
knowledge. Two sampling events were conducted, one in 1995 and one in 
1996.

C. EPA Analysis

    Occidental Chemical used SW-846 Methods 8260A, 8270B, 6010, 8290 to 
quantify the total constituent concentrations of 40 CFR, Part Sec. 264 
Appendix IX Volatiles (including 2-ethoxyethanol, chloroethylene, 
vinyldene chloride and trichloromethane), Appendix IX Semivolatiles 
(excluding PCBs, Pesticides, Herbicides) Appendix IX Metals, and 
Appendix IX Dioxins/Furans. Occidental Chemical used SW-846 Methods 
9045, 9030, 9010, 1311, 9045 to quantify pH, 9030 Reactive Sulfide, and 
9010 Reactive Cyanide. Occidental Chemical used SW-846 Methods 8260A, 
8270B, 6010, 8290 to quantify the constituents from the TCLP extract. 
These analyses were performed on the petitioned waste: the Rockbox 
Residue. The Rockbox Residue, does not meet the definitions for 
reactivity and corrosivity as defined by Secs. 261.22 and 261.23. Table 
2 presents the maximum total constituent and leachate concentrations 
for the Rockbox Residue.

 Table 2--Maximum Total Constituent and Leachate Concentrations Rockbox
                               Residue \1\
------------------------------------------------------------------------
                                    Total constituent  Leachate analyses
           Constituents              analyses (mg/kg)        (mg/l)
------------------------------------------------------------------------
Acetone...........................          0.1           <0.1
Dichloromethane...................          0.007          0.11
Xylene............................          0.011          0.04
Dimethylphthalate.................          0.8            0
2,3,7,8-TCDD Equivalent...........          0.0000781      0.00000000531
Arsenic...........................          2.0           <0.1
Barium............................          4.5            0.13
Chromium..........................          1.0            0.13
Copper............................          1.6           <0.25
Lead..............................          1.0           <0.07
Tin...............................         15             <0.10
Vanadium..........................          8.1           <0.50
Zinc..............................         ND             <0.4
Reactive Sulfide..................        <50
Reactive Cyanide..................        <10
pH................................          8.3
------------------------------------------------------------------------