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Addition of a Subsurface Intrusion Component to the Hazard Ranking System; Corrections

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Environmental Protection Agency (EPA).


Correcting amendments.


On January 9, 2017, the Environmental Protection Agency published a final rule which added subsurface intrusion component to the Superfund Hazard Ranking System. That document inadvertently failed to update the Table of Contents and contained a few other typographical errors. This document corrects the final regulation.


This correction is effective August 3, 2018.

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Terry Jeng, phone: (703) 603-8852, email:, Site Assessment and Remedy Decisions Branch, Assessment and Remediation Division, Office of Superfund Remediation and Technology Innovation (Mailcode 5204P), U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue NW, Washington, DC 20460.

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This is EPA's erratum to the final rule titled Addition of a Subsurface Intrusion Component to the Hazard Ranking System, published January 9, 2017 (82 FR 2760). This is the second set of corrections. The first set of corrections was published in the Federal Register on January 31, 2018 (83 FR 4430). This document augments those corrections.

Section 553 of the Administrative Procedure Act (APA), 5 U.S.C. 553(b)(3)(B), provides that, when an agency for good cause finds that notice and public procedure are impracticable, unnecessary, or contrary to the public interest, the agency may issue a rule without providing notice and an opportunity for public comment. See Utility Solid Waste Activities Group v. EPA, 236 F.3d 749, 752 (D.C. Cir. 2001). We have determined that there is good Start Printed Page 38037cause for making these correcting amendments final without prior proposal and opportunity for public comment. Notice and comment is unnecessary because these administrative or clerical corrections govern the methodology of how EPA, rather than the public or industry, evaluates contaminated sites under the Hazard Ranking System. Similarly, notice and comment is impracticable and contrary to the public interest because the correcting amendments will more quickly ensure that EPA is following the proper procedures to evaluate potential threats to public health from releases of hazardous substances, pollutants, or contaminants. Thus, good cause exists to proceed without notice and public comment.

These correcting amendments are effective immediately upon publication. Section 553(d) of the APA, 5 U.S.C. 553(d), provides that final rules shall not become effective until 30 days after publication in the Federal Register, “except . . . as otherwise provided by the agency for good cause,” among other exceptions. The purpose of this provision is to “give affected parties a reasonable time to adjust their behavior before the final rule takes effect.” Omnipoint Corp. v. FCC, 78 F.3d 620, 630 (D.C. Cir. 1996); see also United States v. Gavrilovic, 551 F.2d 1099, 1104 (8th Cir. 1977) (quoting legislative history). Thus, in determining whether good cause exists to waive the 30-day delay, an agency should “balance the necessity for immediate implementation against principles of fundamental fairness which require that all affected persons be afforded a reasonable amount of time to prepare for the effective date of its ruling.” Gavrilovic, 551 F.2d at 1105. EPA has determined that there is good cause for making these correcting amendments effective immediately because, as stated above, the corrections govern how EPA, rather than the public or industry, applies the Hazard Ranking System to evaluate potential threats to public health from releases of hazardous substances, pollutants, or contaminants. Accordingly, EPA finds that good cause exists under section 553(d)(3) to make this rule effective immediately upon publication.

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List of Subjects in 40 CFR Part 300

  • Environmental protection
  • Air pollution control
  • Chemicals
  • Hazardous substances
  • Hazardous waste
  • Intergovernmental relations
  • Natural resources
  • Oil pollution
  • Penalties
  • Reporting and recordkeeping requirements
  • Superfund
  • Water pollution control
  • Water supply
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Dated: June 29, 2018.

Barry N. Breen,

Acting Assistant Administrator, Office of Land and Emergency Management.

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40 CFR part 300 is corrected as follows:

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1. The authority citation for part 300 continues to read as follows:

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Authority: 33 U.S.C. 1321(d); 42 U.S.C. 9601-9657; E.O. 13626, 77 FR 56749, 3 CFR, 2013 Comp., p. 306; E.O. 12777, 56 FR 54757, 3 CFR, 1991 Comp., p.351; E.O. 12580, 52 FR 2923, 3 CFR, 1987 Comp., p. 193.

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2. Amend Appendix A to Part 300 by:

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a. In the Table of Contents revising the entries for “5.0” through “5.3”; and

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b. Revising Table 2-5, Table 5-16, and Table 7-1.

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The revisions read as follows:

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Appendix A to Part 300—The Hazard Ranking System

Table of Contents

List of Figures

List of Tables

* * * * *

5.0 Soil Exposure and Subsurface Intrusion Pathway.

5.0.1 Exposure components.

5.1 Soil exposure component.

5.1.0 General considerations.

5.1.1 Resident population threat. Likelihood of exposure. Waste characteristics. Toxicity. Hazardous waste quantity. Calculation of waste characteristics factor category value. Targets. Resident individual. Resident population. Level I concentrations. Level II concentrations. Calculation of resident population factor value. Workers. Resources. Terrestrial sensitive environments. Calculation of resident population targets factor category value. Calculation of resident population threat score.

5.1.2 Nearby population threat. Likelihood of exposure. Attractiveness/accessibility. Area of contamination. Likelihood of exposure factor category value. Waste characteristics. Toxicity. Hazardous waste quantity. Calculation of waste characteristics factor category value. Targets. Nearby individual. Population within 1 mile. Calculation of nearby population targets factor category value. Calculation of nearby population threat score.

5.1.3 Calculation of soil exposure component score.

5.2 Subsurface intrusion component.

5.2.0 General considerations.

5.2.1 Subsurface intrusion component. Likelihood of exposure. Observed exposure. Potential for exposure. Structure containment. Depth to contamination. Vertical migration. Vapor migration potential. Calculation of potential for exposure factor value. Calculation of likelihood of exposure factor category value. Waste characteristics. Toxicity/degradation. Toxicity. Degradation. Calculation of toxicity/degradation factor value. Hazardous waste quantity. Calculation of waste characteristics factor category value. Targets. Exposed individual. Population. Level I concentrations. Level II concentrations. Population within area(s) of subsurface contamination. Calculation of population factor value. Resources. Calculation of targets factor category value.

5.2.2 Calculation of subsurface intrusion component score.

5.3 Calculation of the soil exposure and subsurface intrusion pathway score.

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Table 2-5—Hazardous Waste Quantity Evaluation Equations

TierMeasureUnitsEquation for assigning value a
AHazardous constituent quantity (C)lbC.
B bHazardous wastestream quantity (W)lbW/5,000.
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C bVolume (V)
Surface impoundmentyd3V/2.5.
Surface impoundment (buried/backfilled)yd3V/2.5.
Drums cgallonV/500.
Tanks and containers other than drumsyd3V/2.5.
Contaminated soilyd3V/2,500.
D bArea (A)
Surface impoundmentft2A/13.
Surface impoundment (buried/backfilled)ft2A/13.
Land treatmentft2A/270.
Contaminated soilft2A/34,000.
a Do not round to nearest integer.
b Convert volume to mass when necessary: 1 ton = 2,000 pounds = 1 cubic yard = 4 drums = 200 gallons.
c If actual volume of drums is unavailable, assume 1 drum=50 gallons.
d Use land surface area under pile, not surface area of pile.
* * * * *

Table 5-16—Values for Vapor Pressure and Henry's Constant

Assigned value
Vapor Pressure (Torr):
Greater than 103
1 to 102
Less than 10
Henry's Constant (atm-m3/mol):
Greater than 10 33
Greater than 10 4 to 10 32
10 5 to 10 41
Less than 10 50
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Table 7-1—HRS Factors Evaluated Differently for Radionuclides

Ground water pathwayStatus aSurface water pathwayStatus aSoil exposure component of SESSI pathwayStatus aSubsurface intrusion component of SESSI pathwayStatus aAir pathwayStatus a
Likelihood of ReleaseLikelihood of ReleaseLikelihood of ExposureLikelihood of ExposureLikelihood of Release
Observed ReleaseYesObserved ReleaseYesObserved ContaminationYesObserved ExposureYesObserved ReleaseYes.
Potential to ReleaseNoPotential to ReleaseNoAttractiveness/Accessibility to Nearby ResidentsNoPotential for ExposureYesGas Potential to ReleaseNo.
ContainmentNoOverland Flow ContainmentNoArea of ContaminationNoStructure ContainmentNoGas ContainmentNo.
Net PrecipitationNoRunoffNoDepth to ContaminationYesGas Source TypeNo.
Depth to AquiferNoDistance to Surface waterNoVertical migrationNoGas Migration PotentialNo.
Travel TimeNoFlood FrequencyNoVapor Migration PotentialNoParticulate Potential to ReleaseNo.
Flood ContainmentNoArea of Observed ExposureNoParticulate ContainmentNo.
Area of Subsurface ContaminationNoParticulate Source TypeNo.
Particulate Migration PotentialNo.
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Waste CharacteristicsWaste CharacteristicsWaste CharacteristicsWaste CharacteristicsWaste Characteristics
MobilityNoPersistence/MobilityYes/NoHazardous Waste QuantityYesHazardous Waste QuantityYesMobilityNo.
Hazardous Waste QuantityYesBioaccumulation PotentialNoHazardous Waste QuantityYes.
Hazardous Waste QuantityYes
Nearest WellYesbNearest IntakeYesbResident IndividualYesbExposed IndividualYesbNearest IndividualYes.b
PopulationYesbDrinking Water PopulationYesbResident PopulationYesbPopulationYesbPopulationYes.b
Wellhead Protection AreaNoSensitive EnvironmentsYes bResourcesNoSensitive EnvironmentsNo.
Human Food Chain IndividualYes bTerrestrial Sensitive EnvironmentsNo
Human Food Chain PopulationYes bNearby Individual Population Within 1 MileNo No.
a—Factors evaluated differently are denoted by “yes”; factors not evaluated differently are denoted by “no”.
b—Difference is in the determination of Level I and Level II concentrations.
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[FR Doc. 2018-16605 Filed 8-2-18; 8:45 am]