[Federal Register Volume 60, Number 235 (Thursday, December 7, 1995)]
[Proposed Rules]
[Pages 62794-62806]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-29897]



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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 261

[SW-FRL-5342-6]


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

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule and request for comment.

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SUMMARY: The Environmental Protection Agency (EPA or Agency) today is 
proposing to grant a petition submitted by Bethlehem Steel Corporation 
(``BSC''), Lackawanna, New York, to exclude (or ``delist''), on a one-
time basis, certain solid wastes contained in a landfill from being 
listed hazardous wastes. Based on careful analyses of the waste-
specific information provided by the petitioner, the Agency has 
concluded that BSC's petitioned waste will not adversely affect human 
health and the environment. This action responds to BSC's petition to 
delist these wastes on a ``generator-specific'' basis from the 
hazardous waste lists. If the proposed decision is finalized, the 
petitioned waste will not be subject to regulation under Subtitle C of 
the Resource Conservation and Recovery Act (RCRA).
    The Agency is also proposing the use of a fate and transport model 
(the ``EPACML'' 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. Specifically, 
EPA proposes to use this model to predict the concentration of 
hazardous constituents that may be released from the petitioned waste 
into groundwater if the petitioned waste is delisted and then disposed 
of in a Subtitle D landfill.

DATES: 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 January 22, 1996. 
Comments postmarked after the close of the comment period will be 
stamped ``late''.
    Any person may request a hearing on this proposed decision by 
filing a request with the Director, Hazardous Waste Identification 
Division, Office of Solid Waste, whose address appears below, by 
December 22, 1995. 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 Docket Clerk, Office of Solid Waste (Mail Code 5305), 
U.S. Environmental Protection Agency, 401 

[[Page 62795]]
M Street SW., Washington, DC 20460. A third copy should be sent to 
James Kent, Waste Identification Branch, Office of Solid Waste (Mail 
Code 5304), U.S. Environmental Protection Agency, 401 M Street SW., 
Washington, DC 20460. Identify your comments at the top with this 
regulatory docket number: ``F-95-B5EP-FFFFF''.
    Requests for a hearing should be addressed to the Director, 
Hazardous Waste Identification Division, Office of Solid Waste (Mail 
Code 5304), U.S. Environmental Protection Agency, 401 M Street SW., 
Washington, DC 20460.
    The RCRA regulatory docket for this proposed rule is located at 
Crystal Gateway #1, 1st Floor, 1235 Jefferson Davis Highway, Arlington, 
VA, and is available for viewing from 9:00 a.m. to 4:00 p.m., Monday 
through Friday, excluding Federal holidays. Call (703) 603-9230 for 
appointments. The public may copy material from any regulatory docket 
at no cost for the first 100 pages, and at a cost of $0.15 per page for 
additional copies.

FOR FURTHER INFORMATION, CONTACT: For general information, contact the 
RCRA Hotline, toll free at (800) 424-9346, or at (703) 412-9810. For 
technical information concerning this notice, contact Chichang Chen, 
Waste Identification Branch, Office of Solid Waste (Mail Code 5304), 
U.S. Environmental Protection Agency, 401 M Street SW., Washington, DC 
20460, (202) 260-7392.

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 Sec. 261.31 
and Sec. 261.32. These wastes are listed as hazardous because they 
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 
Sec. 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, Sec. 260.20 and Sec. 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, first, 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. Second, the Administrator must 
determine, where he/she has a reasonable basis to believe that factors 
(including additional constituents) other than those for which the 
waste was listed could cause the waste to be a hazardous waste, that 
such factors do not warrant retaining the waste as a hazardous waste. 
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 Agency 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 non-hazardous 
based on the hazardous waste characteristics.
    In addition, residues from the treatment, storage, or disposal of 
listed hazardous wastes and mixtures containing listed hazardous wastes 
are also considered hazardous wastes. 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 Agency on procedural grounds. 
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). The Agency plans to address issues related to waste mixtures and 
residues in a future rulemaking.

B. Approach Used To Evaluate This Petition

    This petition requests a delisting for a hazardous waste listed as 
K060. In making the initial delisting determination, the Agency 
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 
Agency agrees with the petitioner that the waste is non-hazardous with 
respect to the original listing criteria. (If the Agency 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.) 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. See Secs. 260.22 (a) and (d). The Agency 
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 
quantities of waste generated, and waste variability.
    For this delisting determination, the Agency used such information 
to identify plausible exposure routes (i.e., groundwater, surface 
water, air) for hazardous constituents present in the petitioned waste. 
The Agency determined that disposal in a Subtitle D landfill is the 
most reasonable, worst-case disposal scenario for BSC's petitioned 
waste, and that the major exposure route of concern would be ingestion 
of contaminated groundwater. Therefore, the Agency is proposing to use 
a particular fate and transport model (the ``EPACML'' model) 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 BSC's petitioned waste on human 
health and the environment.
    Specifically, the Agency used the maximum estimated waste volume 
and the maximum reported leachate concentrations as inputs to estimate 
the constituent concentrations in the groundwater 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 
used in delisting decision-making for the hazardous constituents of 
concern.
    EPA believes that this fate and transport model represents a 
reasonable worst-case scenario for disposal of the petitioned waste in 
a landfill, and that a reasonable worst-case scenario is appropriate 
when evaluating whether a waste should be relieved of the protective 
management constraints of 

[[Page 62796]]
RCRA Subtitle C. The use of a reasonable worst-case scenario results in 
conservative values for the compliance-point concentrations and ensures 
that the waste, once removed from hazardous waste regulation, will not 
pose a threat to human health or the environment. Because a delisted 
waste is no longer subject to hazardous waste control, the Agency is 
generally unable to predict and does not 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. For example, a generator may petition the 
Agency for delisting of a metal hydroxide sludge which is currently 
being managed in an on-site landfill and provide data on the nearest 
drinking water well, permeability of the aquifer, dispersivities, etc. 
If the Agency were to base its evaluation solely on these site-specific 
factors, the Agency might conclude that the waste, at that specific 
location, cannot affect the closest well, and the Agency might grant 
the petition. Upon promulgation of the exclusion, however, the 
generator is under no obligation to continue to manage the waste at the 
on-site landfill. In fact, the generator may well choose to either send 
the delisted waste off site immediately, or eventually reach the 
capacity of the on-site facility and subsequently send the waste off 
site to a facility which may have very different hydrogeological and 
exposure conditions.
    The Agency also considers the applicability of ground-water 
monitoring data during the evaluation of delisting petitions. In this 
case, the Agency determined that, because BSC is seeking a delisting 
for waste managed on-site, ground-water monitoring data collected from 
the area where the petitioned waste is contained are necessary to 
determine whether hazardous constituents have migrated to the 
underlying groundwater. Ground-water monitoring data collected from 
BSC's monitoring wells will help characterize the potential impact (if 
any) of the disposal of BSC's waste on human health and the 
environment.
    The Agency provides 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. Late comments will 
be considered to the extent possible.

II. Disposition of Delisting Petition Bethlehem Steel Corporation, 
Lackawanna, New York

A. Petition for Exclusion

    Bethlehem Steel Corporation (BSC), located in Lackawanna, New York, 
was engaged in primary metal-making and coke-making operations prior to 
1983. BSC petitioned the Agency to exclude, on a one-time basis, the 
waste contained in an on-site landfill, presently listed as EPA 
Hazardous Waste No. K060--``Ammonia still lime sludge from coking 
operations''. The listed constituents of concern for EPA Hazardous 
Waste No. K060 are cyanide, naphthalene, phenolic compounds, and 
arsenic. BSC refers to this landfill as Hazardous Waste Management Unit 
No. 2 (HWM-2). Although only a portion of the waste in the landfill is 
the ammonia still lime sludge, the entire volume of waste is considered 
to be a listed waste in accordance with Sec. 261.3(a)(2)(iv) (i.e., the 
mixture rule). The mixture of listed ammonia still lime sludge and 
solid waste contained in HWM-2 is the subject of this petition.
    BSC petitioned the Agency to exclude its waste because it does not 
believe that the waste meets the criteria of the listing. BSC claims 
that the mixture of ammonia still lime sludge and solid waste is not 
hazardous because the constituents of concern, although present in the 
waste, are present in either insignificant concentrations or, if 
present at significant levels, are essentially in immobile forms. BSC 
also believes that this waste is not hazardous for any other reason 
(i.e., there are no additional constituents or factors that could cause 
the waste to be hazardous). Review of this petition included 
consideration of the original listing criteria, as well as the 
additional factors required by the Hazardous and Solid Waste Amendments 
(HSWA) of 1984. See Section 222 of HSWA, 42 USC 6921(f), and 40 CFR 
260.22(d)(2)-(4). Today's proposal to grant this petition for delisting 
is the result of the Agency's evaluation of BSC's petition.

B. Background

    On July 18, 1984, BSC petitioned the Agency to exclude the waste 
contained in its on-site landfill identified as HWM-2, and subsequently 
provided additional information. After evaluating the petition, the 
Agency proposed to deny BSC's petition to exclude the waste contained 
in HWM-2 on April 7, 1989 (see 54 FR 14101). The Agency's evaluation of 
the petition, which used the ``VHS'' fate and transport model and the 
analytical data provided by BSC, indicated that the petitioned waste 
exhibited significant concentrations of leachable lead and 
benzo(a)pyrene. Furthermore, the Agency considered the sampling and 
analysis program conducted in support of the petition to be incomplete. 
Moreover, groundwater monitoring data collected from wells monitoring 
this on-site landfill indicated that the landfill may have been 
adversely impacting groundwater quality at the site. The Agency 
received public comments on the April 7, 1989 proposed decision between 
April and June 1989. On January 29, 1990, the Agency re-opened the 
comment period to enable public review of information supporting the 
proposed delisting health-based level for benzo(a)pyrene (see 55 FR 
2847). The Agency published a final denial, including responses to 
public comments, in the Federal Register on August 26, 1991 (see 56 FR 
41944). On October 30, 1991, BSC petitioned the U.S. Court of Appeals 
for the District of Columbia Circuit to overturn EPA's denial decision. 
Subsequently, BSC agreed to stay this litigation for a re-evaluation by 
EPA using a new fate and transport model (EPACML) and updated health-
based levels, and on November 17, 1992 submitted extensive supplemental 
waste characterization and groundwater monitoring data. After reviewing 
the new data in conjunction with the existing petition information, the 
Agency now believes that the petitioned waste is eligible for an 
exclusion based on the current evaluation criteria. Therefore, the 
Agency hereby proposes to withdraw its final denial decision and to 
grant BSC's petition. The Agency's decision to re-evaluate BSC's 
petition was based on additional waste characterization and groundwater 
data that was collected subsequent to the publication of the final 
denial decision. The Agency's re-evaluation of BSC's petitioned waste 
contained in the HWM-2 landfill is the subject of today's proposal.
    In support of its petition, BSC submitted: (1) detailed 
descriptions and schematics of its manufacturing process; (2) a list of 
all raw materials and Material Safety Data Sheets (MSDS) for all trade 
name materials that might be expected to have contributed to the waste; 
(3) results from total constituent analyses for the eight Toxicity 
Characteristic (TC) metals listed in Sec. 261.24, antimony, nickel, 
thallium, and cyanide; (4) results from the Toxicity Characteristic 
Leaching Procedure (TCLP; SW-846, Method 1311) for the eight TC metals, 
antimony, nickel, and thallium; (5) results from the EP leachate 
procedure for the eight TC 

[[Page 62797]]
metals, nickel, and cyanide; (6) results from total constituent 
analyses for sulfide and reactive sulfide; (7) results from total oil 
and grease analyses; (8) results from characteristics testing for 
ignitability, corrosivity, and reactivity; (9) results from total 
constituent analyses for 70 volatile organic and semivolatile organic 
constituents, including the TC organic constituents (excluding 
pesticides and herbicides); (10) results from the TCLP analyses for 63 
volatile organic and semivolatile organic constituents, including the 
TC organic constituents (excluding pesticides and herbicides); and (11) 
groundwater monitoring data collected from wells monitoring the on-site 
landfill.
    BSC conducted primary metal-making and coke-making operations 
during the period the ammonia still lime sludge was generated. In 
October 1983, BSC discontinued its primary metal-making operations and 
modified its coking processes so that the ammonia still lime sludge was 
no longer generated. (BSC now uses sodium hydroxide as the strong base 
at the ammonia still rather than lime slurry, and therefore ammonia 
still lime sludge is no longer generated.)
    BSC's steel-making process involved refining molten iron with 
oxygen, flux (i.e., dolomite or lime), and alloying materials in a 
basic oxygen furnace to produce carbon steels. BSC's iron-making 
process involved smelting of iron-bearing materials (i.e., iron ore, 
sinter, and scrap) with coke, flux (i.e., dolomite and lime), and 
preheated air in blast furnaces. The blast furnace slurry disposed of 
in BSC's landfill originated from the water scrubbing of blast furnace 
gas. According to BSC, blast furnace sludge has not been produced since 
the final removal of sludge from the thickener in November 1983.
    Coke-making involves the destructive distillation of bituminous 
coal in coke ovens. Volatile matter evolves during the coking process 
(including the moisture content of the coal) and leaves the ovens 
through coke oven gas off-takes. This hot coke oven gas is cooled by 
spraying it with recycled flushing liquor consisting of a weak ammonia 
liquor (WAL) solution. As the coke oven gas is cooled, water and tar 
are condensed. The tar fraction is separated from the aqueous WAL in a 
decanter. The majority of the WAL is recycled back to the coke oven gas 
cooling process as flushing liquor. Any excess WAL is processed by 
solvent extraction to recover phenol or sodium phenolate. The excess 
WAL then is processed by steam stripping to release aqueous ammonia 
into the gas phase in an ammonia still. In the upper portion of the 
still, free ammonia is stripped by steam (at temperatures of about 100 
deg.C) and ammonia vapor rising from the lower portion. In the lower 
portion of the still, fixed ammonia compounds are dissociated by 
adjusting the pH with lime slurry and then injecting steam. The spent 
ammonia still lime slurry is drawn off the bottom and discharged to one 
of two settling basins. The sludge that settles out in these basins 
(i.e., ammonia still lime sludge) is subsequently placed in the on-site 
landfill.
    As stated previously, BSC disposed of its ammonia still lime sludge 
in its on-site HWM-2 landfill with other solid wastes between 1969 and 
November of 1983. BSC is not currently disposing of wastes in this 
landfill. Based on available records, BSC estimates that approximately 
two percent of the waste placed in the landfill is ammonia still lime 
sludge. The most significant wastes that were disposed of in the 
landfill include: blast furnace thickener sludge, basic oxygen furnace 
thickener sludge, sinter plant sludge, sludges generated from the 
treatment of wastewaters from a cold rolling mill, a steel pickling 
operation, and a hot-dip galvanizing line, and dredging spoils (from 
Smokes Creek). Only the ammonia still lime sludge is a listed hazardous 
waste.
    BSC's preliminary sampling demonstration included data on ten 
samples collected from the landfill in January 1984. A detailed 
description of procedures used to collect three of these samples was 
not provided and is not available. For the remaining seven samples, BSC 
divided the landfill into four sections and randomly selected a partial 
core sample (i.e., two-foot core samples were taken as opposed to full-
depth core samples) from each of the four sections, two partial core 
samples from the central portion of the landfill, and an additional 
partial core sample from the southeast section. A grab sample was then 
taken from each of these seven core samples, resulting in seven grab 
samples. The three samples for which sampling procedure descriptions 
were not provided were analyzed for total constituent (i.e., mass of a 
particular constituent per mass of waste) and extraction procedure (EP) 
leachable (i.e., mass of a particular constituent per unit volume of 
extract) concentrations of arsenic, cyanide, naphthalene, and phenolic 
compounds. The extraction procedure used in these analyses, however, 
was not equivalent with the procedure described in SW-846 Method 1310 
and therefore these data were not considered in the evaluation of BSC's 
petition. (For a more detailed description of the extraction procedure 
used by BSC, see the RCRA public docket for today's notice.) The 
remaining seven grab samples were analyzed (using the EP) for leachable 
concentrations of the eight TC metals, nickel, cyanide, and sulfide; 
and the characteristics of corrosivity and reactivity.
    BSC collected a second set of samples during April 1984. To collect 
these samples, BSC divided the landfill into six sections of 
approximately equal size. Within each section, six discrete samples 
were taken at random depths from evenly spaced boring locations. The 
samples then were composited, by section, to form six representative 
samples, one composite per section. These six composite samples were 
analyzed for total constituent concentrations of the eight TC metals, 
nickel, cyanide, benzene, benzo(a)pyrene, naphthalene, phenolic 
compounds, and tetrachloroethylene. In addition, these six composite 
samples were analyzed (using the EP) for leachable concentrations of 
the eight TC metals, nickel, and cyanide; total oil and grease content; 
and the characteristic of ignitability.
    At EPA's request, BSC conducted additional sampling and testing of 
the central portion of the landfill in February of 1985. Specifically, 
BSC collected approximately ten two-foot long core samples from six 
locations within the central portion of the landfill. For each 
location, grab samples were taken from each of the core samples 
(approximately ten) and composited. These six composite samples were 
analyzed for total constituent and leachable concentrations (using the 
EP) of the eight TC metals (excluding mercury, selenium, and silver), 
nickel, and cyanide. In addition, these six composite samples were 
analyzed for total constituent concentrations of sulfide, benzene, 
benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, 
indeno(1,2,3-cd)pyrene, naphthalene, and phenolic compounds; and total 
oil and grease content.
    In its comments to the Agency's April 7, 1989 proposed denial of 
its petition, BSC submitted the analytical results of an additional 
sampling event. In September 1988, four full-depth core samples were 
obtained from the landfill and were composited to form one composite 
sample. This sample was analyzed using the TCLP to quantify leachable 
concentrations of the TC contaminants listed in Sec. 261.24 (excluding 
the pesticides/herbicides) and thirteen other organic constituents.
    In June 1992, following the publication of the final denial notice 
for 

[[Page 62798]]
BSC's petition in the Federal Register (see 56 FR 41944; August 26, 
1991), BSC conducted additional sampling and testing of its petitioned 
waste. BSC established a uniform grid over the landfill dividing the 
landfill into seventeen sections, each 100 feet by 100 feet. Within 
each grid section a second uniform grid of 10-foot intervals was 
established for the selection of the individual boring locations. 
Alternating 10,000 square foot grid sections were selected for 
sampling. BSC used a random number table to select five boring 
locations within each 10,000 square foot grid section. This resulted in 
the selection of eight grid sections to yield eight composite samples 
of the material in the landfill, with each composite representative of 
five full-core sample aliquots from each grid section. These eight 
composite samples were analyzed for total constituent concentrations of 
83 toxicants of potential concern1 (including the eight TC 
metals). These eight composite samples were also analyzed for TCLP 
leachate concentrations of the toxicants of potential concern 
(excluding cyanide and polychlorinated biphenyls (PCBs)); and total oil 
and grease.

    \1\BSC chose to analyze waste samples for these constituents 
because they were: (1) identified by EPA during previous actions 
concerning this petition as constituents of regulatory concern, or 
(2) identified as constituents that reasonably may be expected to be 
potentially present in the petitioned waste, based on the processes 
from which the waste components were derived.
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    BSC claims that the analytical data obtained from the four sampling 
events that occurred from April 1984 through June 1992 are 
representative of any variation in the constituent concentrations in 
the petitioned waste. BSC believes that the data from the preliminary 
grab samples obtained in January 1984 are not representative of the 
entire waste volume contained in the landfill. BSC also believes that 
it has addressed the Agency's concern regarding the number of samples 
collected and the target analyses, as originally noted by the Agency in 
the April 7, 1989 proposal to deny BSC's petition. Specifically, in 
that proposal the Agency noted that, based on the dimensions of the 
landfill containing the petitioned waste, BSC should have collected at 
least one sample for every 10,000 square foot section of the landfill. 
BSC's original estimate of the areal extent of the landfill was 5.3 
acres; however, as discussed later in today's notice, BSC has 
demonstrated through detailed calculations (discussed later in today's 
notice) that a better estimate of the landfill area is 3.5 acres. 
Therefore, based on this revised estimate, BSC should have collected at 
least 15 composite samples. Since the April 1989 proposal, BSC has 
conducted additional sampling of the waste, bringing the total number 
of composite samples to 21, including 8 composite samples collected in 
June 1992 that have been analyzed for total constituent concentrations 
of 70 volatile organic and semivolatile organic constituents. The 
Agency believes, based on its re-evaluation of BSC's petition, that the 
combined results of BSC's sampling events are sufficient to 
characterize any variation in the constituent concentrations in the 
petitioned waste.
    BSC also submitted ground-water monitoring information collected 
from wells monitoring the landfill to demonstrate that the petitioned 
waste was not adversely impacting ground-water quality. The ground-
water monitoring information submitted by BSC, and more recent data 
received from State and EPA Regional authorities, included: (1) Well 
location information; (2) boring logs and well construction information 
for each well; (3) water levels and water level contour maps; and (4) 
results of the analysis of ground-water samples.

C. Agency Analysis

    BSC used SW-846 Methods 7060 through 7760 (January 1984, April 
1984, and February 1985 samples) to quantify the total constituent 
concentrations of the eight TC metals and nickel. BSC used SW-846 
Method 6010 (June 1992 samples) to quantify the total constituent 
concentrations of the eight TC metals (with the exception of mercury 
and selenium, for which BSC used SW-846 Methods 7471 and 7740, 
respectively), nickel, antimony, and thallium. ``Methods for Chemical 
Analysis of Water and Wastes'' Method 335.2 (April 1984 samples), SW-
846 Method 9010 (February 1985 samples) and SW-846 Method 9012 (June 
1992 samples) were used to quantify total cyanide concentrations in the 
petitioned waste. SW-846 Method 9030 (February 1985 samples) was used 
to quantify total sulfide levels in the petitioned waste. SW-846 Method 
7.3.4.1 (June 1992 samples) was used to quantify reactive sulfide 
levels in the petitioned waste. SW-846 Method 1310 (samples prior to 
1988) was used to determine the leachable concentrations of the eight 
TC metals, nickel, and cyanide. BSC prepared a toxicity characteristic 
leachate (according to the procedure in 51 FR 21685, June 13, 1986) to 
determine the leachable concentrations of the eight TC metals in the 
September 1988 sample. SW-846 Method 1311 was used to determine the 
leachable concentrations of the eight TC metals, nickel, antimony, and 
thallium in the June 1992 samples. Table 1 presents the maximum 
reported, and 95% Upper Confidence Limit (UCL) total constituent 
concentrations of the eight TC metals listed in Sec. 261.24, nickel, 
antimony, thallium, cyanide, and sulfide. Table 1 also identifies the 
number of samples in which each constituent was detected. Table 2 
presents the maximum reported, and 95% UCL EP leachate and TCLP 
leachate concentrations of the eight TC metals listed in Sec. 261.24, 
nickel, antimony, thallium, and cyanide. (Analysis for leachable 
concentrations of sulfide or reactive sulfide is not necessary because 
the Agency's level of regulatory concern is based on the total 
constituent concentration of reactive sulfide.)

      Table 1.--Total Constituent Concentrations (mg/kg) Inorganic      
                              Constituents                              
------------------------------------------------------------------------
                                 Total Concentrations (mg/    Number of 
                                            kg)               Samples in
                               -----------------------------    which   
         Constituents                                         detected/ 
                                                                total   
                                 Maximum\1\     95% UCL\2\    number of 
                                                               samples  
------------------------------------------------------------------------
Antimony......................       <12            <12              0/8
Arsenic.......................        16.2           10.3          12/23
Barium........................     1,660            791            13/20
Cadmium.......................         3.3            2.1          12/20
Chromium......................       172            100            20/20
Lead..........................     7,520          2,810           20/20 

[[Page 62799]]
                                                                        
Mercury.......................         0.268          0.16          6/14
Nickel........................        64.6           30.6          12/20
Selenium......................         2.6            2.2           6/14
Silver........................         3.0            2.1           8/14
Thallium......................        43             32.6            5/8
Cyanide (total)...............        43.1           36.0          20/23
Reactive Sulfide..............       140            130.0           7/8 
------------------------------------------------------------------------
< Denotes that the constituent was not detected at the detection limit  
  specified in the table.                                               
\1\ These levels represent the highest detected concentrations of each  
  inorganic constituent found in any sample of the petitioned waste,    
  and, if not detected, the highest detection limit. These levels do not
  necessarily represent the specific levels found in one sample.        
\2\ 95% Upper Confidence Limit (UCL) is the estimated upper 95 percent  
  confidence interval for the average of sample concentrations based on 
  the Student-t distribution applied to random samples. The average was 
  calculated by considering nondetectable measurements to be            
  measurements at the detection limits, except for arsenic, for which   
  high detection limits (<100 mg/kg) for eight samples were not         
  included.                                                             



                     Table 2.--EP/TCLP Leachate Concentrations (mg/l) Inorganic Constituents                    
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                                                                  EP/TCLP Leachate Concentrations (mg/l)        
                                                         -------------------------------------------------------
                      Constituents                                Maximum\1\                  95% UCL\2\        
                                                         -------------------------------------------------------
                                                               EP           TCLP           EP           TCLP    
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Antimony................................................       NA             <0.06        NA             <0.06 
Arsenic.................................................        0.034         <0.3          0.016          0.16 
Barium..................................................        1.48           0.7          0.85           0.54 
Cadmium.................................................        0.015         <0.005        0.005         <0.005
Chromium................................................        0.144          0.023        0.034          0.024
Lead....................................................        1.61           0.11         0.37           0.059
Mercury.................................................        0.0007        <0.005        0.0004        <0.002
Nickel..................................................        0.59           0.21         0.28           0.15 
Selenium................................................        0.008         <0.3          0.003         <0.15 
Silver..................................................       <0.001         <0.01        <0.001         <0.01 
Thallium................................................       NA          \3\<0.3         NA             <0.17 
Cyanide (total).........................................        0.06        \4\2.1          0.03         NA     
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