[Federal Register Volume 65, Number 140 (Thursday, July 20, 2000)]
[Notices]
[Pages 45052-45055]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-18437]


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ENVIRONMENTAL PROTECTION AGENCY

[SW-FRL-6838-8]


No-Migration Variance From Land Disposal Restrictions for Exxon 
Mobil Corporation, Billings, MT South Land Treatment Unit

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of final decision.

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SUMMARY: EPA is reissuing a no-migration variance (``variance'') for 
land disposal of hazardous waste to Exxon Mobil Refining & Supply 
Company Billings Refinery (``Exxon''), a division of Exxon Mobil 
Corporation, formerly known as Exxon Company U.S.A. Authority for the 
decision has been delegated to the EPA Regional Administrator. This 
variance approved under Resource Conservation and Recovery Act (RCRA) 
regulations allows Exxon to place certain untreated hazardous wastes 
subject to the RCRA land disposal restrictions (42 U.S.C. 36901 et 
seq.) at their Billings (Montana) refinery South Land Treatment Unit 
(SLTU). Exxon submitted a request to EPA on March 24, 1998 for renewal 
of the no-migration variance in conjunction with their State of Montana 
hazardous waste permit reissuance. Exxon also petitioned to amend the 
variance by adding the newly listed hazardous waste, Petroleum Refinery 
Primary Oil/Water/Solids Separation Sludge (EPA hazardous waste code 
F037) generated at the Exxon Refinery in Billings, Montana.

[[Page 45053]]

    The variance granted today covers the following wastes generated at 
the Exxon Billings Refinery: Slop Oil Emulsion Solids (K049); API 
Separator Sludge (K051); Toxicity Characteristic Contaminated Soils 
(D018); and Petroleum Refinery Primary Oil/Water/Solids Separation 
Sludge (F037). Exxon may continue to dispose of non-hazardous solid 
wastes and non-restricted hazardous wastes at the SLTU in compliance 
with its Montana hazardous waste permit (No. MTHWP-99-02). The variance 
does not relieve Exxon of its responsibilities in the management of 
hazardous waste under 40 CFR part 260 through part 271. If Exxon wishes 
to dispose of additional restricted wastes at the SLTU it will have to 
apply for an amendment to its no-migration variance. EPA will evaluate 
the amendment petition and propose a decision for public comment in the 
Federal Register, with a notice in the local press, before a final 
decision is made.
    In granting the original variance on July 27, 1993, we concluded 
that Exxon demonstrated to a reasonable degree of certainty that 
hazardous constituents would not migrate out of the land treatment 
facility at levels exceeding no-migration criteria for as long as the 
wastes remain hazardous. We reviewed the SLTU monitoring data submitted 
by Exxon for the period the original variance was in effect along with 
other relevant information, and it supported our original conclusion on 
Exxon's no-migration demonstration. We also concluded that Exxon 
adequately met the conditions of the original variance, which were 
included to ensure compliance with their no-migration demonstration. 
The variance reissuance again includes specific conditions (below) 
Exxon must meet to maintain the variance. In accordance with 40 CFR 
268.6(k), the variance is valid for up to ten years from the date of 
EPA approval of the petition, but no longer than the term of Exxon's 
RCRA permit. The term of the variance expires upon the termination or 
denial of Exxon's Montana hazardous waste permit No. MTHWP-99-02), 
which will expire on June 28, 2009, or when the volume limit of waste 
to be land disposed during the term of the variance is reached.
    RCRA regulations require that we provide for public comment on a 
proposed no-migration variance decision. EPA published notice of our 
proposed decision in the local press and in the Federal Register on 
April 21, 2000 (65 FR 21419). We also provided opportunity for public 
participation through a 45-day comment period, and held a public 
hearing in Billings, Montana on April 23, 2000. The public comment 
period closed on June 5, 2000. We did not receive any comments on our 
proposed decision. Therefore, EPA decided to reissue the variance and 
add Primary Sludge (F037) as described in the preceding Federal 
Register document (65 FR 21419). RCRA regulations require that we 
publish notice of our final decision in the Federal Register.

DATES: This final decision becomes effective July 20, 2000.

ADDRESSES: The record supporting this decision is located in Helena, 
Montana, at the EPA Region VIII, Montana Operations Office, Federal 
Building, 301 South Park. The public may make arrangements to view the 
documents in Helena by calling Tina Diebold at (406) 441-1130. The 
record is available for inspection from 8:00 a.m. to 4:00 p.m., Monday 
through Friday, except Federal holidays. Another copy of the record is 
available to the public at the Parmly Library at 510 North Broadway, 
Billings, Montana, and is available for public review during regular 
library hours for the next thirty days.

FOR FURTHER INFORMATION CONTACT: Tina Diebold, Mail Code 8MO, Montana 
Office, U.S. EPA Region VIII, 301 S. Park, Drawer 10096, Helena, 
Montana 59626-0096, at (406) 441-1130.

SUPPLEMENTARY INFORMATION: Wherever ``we'' is used throughout this 
notice, it refers to EPA.

A. Conditions and Reporting Requirements for the Exxon No-Migration 
Variance Reissuance

    As part of this reissuance of the no-migration variance and 
addition of Primary Sludge (F037), Exxon must comply with the following 
conditions. These conditions are in addition to those required of Exxon 
under 40 CFR 268.6. EPA would directly enforce these conditions, and a 
violation of a condition would constitute a violation of the RCRA land 
disposal restrictions. Unless otherwise notified by EPA, Exxon shall 
provide the required notices and reports to the EPA Region VIII Montana 
Operations Office, Federal Building, 301 South Park, Drawer 10096, 
Helena, MT, 59626. Exxon shall provide a separate copy to the State of 
Montana of any report or notice required by the variance if the 
information is not combined with the reports required under its Montana 
hazardous waste permit. Exxon shall provide copies to the State at the 
address specified for its Montana hazardous waste permit reporting 
requirements.
    We interpret the no-migration standard to mean that concentrations 
of hazardous constituents cannot exceed EPA-approved health-based 
levels in any environmental medium at the boundary of the land disposal 
unit. Hazardous constituent levels exceeding those presented in Table 1 
of our proposed decision (65 FR 21421) constitute migration into ground 
water at the unit boundary, as measured by soil-pore liquid and below 
treatment zone (BTZ) soil-core monitoring, and as measured by ground 
water monitoring under the Exxon Montana hazardous waste permit and as 
defined below. In the event that Exxon should detect other RCRA 
hazardous constituents (defined in 40 CFR part 261, appendix VIII) 
above health-based levels, this event would also be subject to the 
notification requirements in 40 CFR 268.6(f). Definitions of the unit 
boundaries (i.e., points of compliance for no-migration purposes) 
remain the same as in the original variance (57 FR 10478). Metals 
levels in the SLTU zone of incorporation (ZOI) soils (the top 23 
centimeters of the treatment zone) exceeding the limits listed in item 
1.a. below are also evidence of a no-migration standard exceedance. EPA 
will determine within 60 days of receiving notice of migration whether 
Exxon can continue to receive prohibited waste in the unit and whether 
the variance is to be revoked.
    Exxon must report to EPA within ten days any significant changes in 
operating conditions from those described or modeled in its original 
petition or reissuance petition, including the petition to amend the 
variance to include Primary Sludge (F037), or at least 30 days in 
advance of initiating any change at or to the unit (40 CFR 268.6(e)). 
EPA will determine the appropriate response, including termination of 
waste acceptance and revocation of the variance, or variance 
modification.
    The term of the variance expires upon the termination or denial of 
Exxon's Montana hazardous waste permit No. MTHWP-99-02), which will 
expire on June 28, 2009, or when the volume limit of waste to be land 
disposed during the term of the variance is reached.

1. Montana Hazardous Waste Permit Conditions

    Exxon must comply with conditions of the Montana hazardous waste 
permit effective June 28, 1999 (No. MTHWP-99-02) regarding 
characterization of wastes disposed of at the SLTU, and monitoring of 
ground water, soil and soil-pore liquids at that unit. Exxon must 
provide the results of this

[[Page 45054]]

characterization and monitoring to EPA on the same schedule as they are 
provided to the State of Montana under Exxon's Montana hazardous waste 
permit.
    In addition, Exxon must follow the monitoring provisions below 
specific to this variance, which are intended to supplement the 
existing Montana hazardous waste permit conditions. Exxon may provide 
the information required as a condition of the variance to EPA in the 
annual reports required by its Montana hazardous waste permit. Exxon 
shall submit annual reports for the previous calendar year by April 30.
    a. ZOI Metals Loading Limit: Exxon shall determine if any of the 
following risk limits have been exceeded when it evaluates the annual 
SLTU ZOI soil samples for the metals loading limits under its Montana 
hazardous waste permit: 31 mg/kg for antimony; 15 mg/kg for arsenic; 2 
mg/kg for beryllium; 140 mg/kg for total chromium; 400 mg/kg for lead; 
and 7 mg/kg for mercury. In the event one or more of these criteria are 
exceeded, Exxon may only place wastes on the SLTU areas(s) for which 
the metals concentrations are less than or equal to the in-soil 
concentration limits. Exxon shall submit the analytical results and 
comparisons in an annual report to EPA. Exxon shall report exceedances 
of these limits to EPA within ten days of receiving the analytical 
results.
    b. Soil-Pore Liquid Monitoring: Exxon shall evaluate the following 
metals as part of semi-annual SLTU soil-pore lysimeter monitoring 
requirements under the Montana hazardous waste permit: antimony, 
arsenic, barium, beryllium, cadmium, chromium, lead, mercury, nickel, 
selenium, vanadium, and zinc. Samples from each of the three SLTU 
lysimeters shall be .45-micron filtered prior to analysis for metals. 
SW-846 \1\ or equivalent analytical methods shall be used which can 
provide reporting limits of .001 mg/l, except .0002 mg/l for mercury. 
Exxon shall attempt to collect sufficient sample volumes to meet these 
performance criteria, following the general analytical priority scheme 
in its Montana hazardous waste permit. Should sample volumes be 
insufficient, Exxon shall investigate collecting additional sample 
volumes in a reasonable time frame for metals analysis once the Montana 
hazardous waste permit conditions have been met. Additionally, analyses 
of soil-pore organic monitoring constituents shall meet the SW-846 
estimated quantitation limits (EQL) specified for water samples in 
Exxon's Montana hazardous waste permit and as listed in Table 1 of our 
proposed decision (65 FR 21421), to the extent possible.
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    \1\ These methods are found in the third edition of ``Test 
Methods for Evaluating Solid Waste Physical/Chemical Methods,'' EPA, 
SW-846, which is available from the Government Printing Office 
(GPO). This compendium of EPA test methods is commonly referred to 
as ``SW-846'' and we will use this term to refer to the compendium 
throughout this notice.
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    c. Soil-Pore Liquid Monitoring Evaluation And Reporting: Exxon 
shall compare the organic hazardous constituents and the metals results 
to the leachate soil-pore health-based standards identified in Table 1 
of our proposed decision (65 FR 21421). Exxon shall submit the 
analytical results and comparisons including information on sample 
volumes collected, analytical methods used, and EQLs achieved for all 
sample constituents, in an annual report to EPA. Exxon shall report 
exceedances of these limits to EPA within ten days of receiving the 
analytical results, and immediately suspend receipt of prohibited waste 
at the unit 40 CFR 268.6(f) upon determination of migration. Exxon 
shall notify EPA and the State if sufficient sample volumes cannot be 
collected or EQLs cannot be achieved in any semi-annual sampling 
period.
    d. BTZ Soil-Core Monitoring: When collecting the five (5) annual 
soil cores from the SLTU Below Treatment Zone (BTZ) as required by its 
Montana hazardous waste permit, Exxon shall also collect intermediate 
level treatment zone soil samples at three depth intervals of 2-2.5 
feet below ground surface (bgs), 3-3.5 feet bgs, and 4-4.5 feet bgs and 
in the BTZ itself (5-5.5 feet bgs), sufficient for analyses of oil and 
grease and soil pH. Oil and grease and soil pH results shall be 
reported for the four depth intervals in each of the five soil core 
samples. Exxon shall use an oil and grease analytical method which can 
provide detection limits in the range of 10 to 100 mg/kg consistent 
with the Montana hazardous waste permit. Exxon also shall analyze any 
BTZ resamples required under the Montana hazardous waste permit for oil 
and grease and soil pH. Exxon shall submit the results of the annual 
BTZ sampling (including the pH and oil and grease results from the 
intermediate levels) in an annual report to EPA. Exxon shall submit the 
results of any resampling to EPA on the same schedule as provided to 
the State under Exxon's hazardous waste permit.
    e. Evaluation of BTZ Soil-Core Monitoring: Analyses for organic 
monitoring constituents shall meet soil low-level required EQLs as 
specified in Exxon's Montana hazardous waste permit and as specified in 
Table 1 of our proposed decision (65 FR 21421). Exxon shall compare the 
results of BTZ soil samples with soil-core health-based standards 
identified in Table 1 of our proposed decision (65 FR 21421). Exxon 
shall submit the analytical results and comparisons in an annual report 
to EPA. Exxon shall report exceedances of these limits to EPA within 
ten days of receiving the analytical results, and immediately suspend 
receipt of prohibited waste at the unit upon determination of 
migration.

2. Annual Benzene Loading Limit

    The total amount of benzene that may be disposed of at the SLTU may 
not exceed a cumulative mass loading of 49 Kg per calendar year. Exxon 
must determine the benzene content of each wastestream, including each 
load of Primary Sludge (F037) prior to placement at the land treatment 
unit. Representative samples of each wastestream must be analyzed for 
benzene as they are generated during the land application season in 
accordance with the promulgated edition of SW-846. The term ``as 
generated'' means each time the wastes are removed from the wastewater 
system, created through a spill, or a tank is cleaned out, and the 
wastes are taken or will be taken to the land treatment unit, which may 
be several times a year. A tracking system must be in place which 
continually estimates and updates the cumulative benzene waste loading 
during the operating season. Exxon must submit a summary of these waste 
analyses demonstrating its compliance with the loading limit to EPA in 
an annual report. When the 49 Kg benzene limit is reached, Exxon must 
not dispose of any additional waste containing detectable levels of 
benzene at the SLTU until the next calendar year. Exxon shall notify 
EPA when the 49 Kg limit is reached within ten days of receiving the 
analytical results.

3. Waste Characterization

    Exxon must identify in the annual report to EPA the following 
additional information for each applied waste at the SLTU: the location 
of waste generation (e.g., Tank 17 sewer, Tank 108 contaminated soil); 
analytical results of waste determination for any wastes for which the 
hazardous status was not known when it was generated, mass of waste; 
application date(s); the hazardous waste code (if any); and the matrix 
(e.g., soil or sludge). In the report, Exxon must distinguish between 
the F037 waste generated from the sewer (e.g., ``F037 sewer sludge'') 
and the F037 waste generated from the

[[Page 45055]]

Alkyllation Unit Neutralization Basins (e.g., ``F037 lime sludge''). In 
the annual report, Exxon must also include the total quantity of waste 
applied at the SLTU during the last operating season and a break down 
of the total quantity of hazardous and of non-hazardous waste.

4. Application of F037 Sewer Sludge

    Exxon's application of Primary Sludge generated from the sewer 
system (F037 sewer sludge) to the SLTU is restricted to times when 
Exxon also applies API Separator Sludge (K051). Exxon must combine the 
F037 sewer sludge with the API Separator Sludge prior to or during 
application at the SLTU. Exxon shall incorporate this condition in its 
waste tracking system to ensure that any time F037 sewer sludge is 
cleared for application to the SLTU, it is accompanied by K051 waste.

5. Application of F037 Lime Sludge

    Exxon's application of Primary Sludge generated from the 
Alkyllation Unit Neutralization Basin (F037 lime sludge) to the SLTU is 
limited to when it has determined pH adjustment of the ZOI soils is 
needed according to the applicable criteria and methods identified in 
its Montana hazardous waste permit. For the years in which Exxon uses 
F037 lime sludge to adjust the pH of the ZOI soils at the SLTU, Exxon 
must submit to EPA the following information in the annual report: pH 
of the F037 lime sludge applied to the SLTU, and the other measurements 
and tests used to determine the need for pH adjustment as well as the 
quantity of F037 lime sludge applied and the quantity of any other 
substance (e.g., lime) used to adjust the pH of the ZOI soil at the 
SLTU.

6. Waste Tracking

    As part of its waste tracking process, Exxon must confirm receipt 
of analytical results for any wastes for which the hazardous status is 
not currently known prior to application of the waste at the SLTU. 
Exxon must comply with its Montana hazardous waste permit conditions 
with regard to restrictions on the application of waste to the SLTU, 
such as any restrictions based on the pH of the waste.

7. Information Requests

    Upon request by EPA, Exxon shall provide to the EPA within a 
reasonable time, any relevant information requested to determine 
compliance with the conditions of this variance.

8. Access

    Exxon shall allow EPA, or authorized representatives, upon the 
presentation of credentials and other documents as may be required by 
law to: (a) Inspect at reasonable times any records, facilities, 
equipment (including monitoring and control equipment), practices, or 
operations related to the disposal of restricted hazardous wastes at 
the SLTU; and (b) sample or monitor at reasonable times, for the 
purposes of assuring compliance with the conditions of this variance or 
to determine migration or as otherwise authorized by RCRA, any wastes 
intended or proposed for disposal at the SLTU and the soil, air, soil-
pore liquids or ground water in or surrounding the SLTU.

    Dated: July 11, 2000.
Rebecca Hanmer,
Acting Regional Administrator, Region VIII.
[FR Doc. 00-18437 Filed 7-19-00; 8:45 am]
BILLING CODE 6560-50-P