ENVIRONMENTAL
QUALITY BOARD[ 25 PA. CODE CH. 250 ] Administration of Land Recycling Program [40 Pa.B. 1297]
[Saturday, March 6, 2010]The Environmental Quality Board (Board) proposes to amend Chapter 250 (relating to Administration of Land Recycling Program). The amendments update the Statewide health standards by using current Environmental Protection Agency (EPA) guidance and updated toxicological information. The proposal also corrects errors and codifies certain established policies into regulation.
This proposal was adopted by the Board at its meeting of December 15, 2009.
A. Effective Date
These amendments will go into effect upon publication in the Pennsylvania Bulletin as final-form rulemaking.
B. Contact Persons
For further information, contact Troy Conrad, Director, Land Recycling Program, P. O. Box 8471, Rachel Carson State Office Building, Harrisburg, PA 17105-8471, (717) 783-7816 or Kurt Klapkowski, Assistant Counsel, Bureau of Regulatory Counsel, P. O. Box 8464, Rachel Carson State Office Building, Harrisburg, PA 17105-8464, (717) 787-7060. Information regarding submitting comments on this proposal appears in Section J of this preamble. Persons with a disability may use the Pennsylvania AT&T Relay Service by calling (800) 654-5984 (TDD users) or (800) 654-5988 (voice users). This proposal is available electronically through the Department of Environmental Protection's (Department) web site at http://www.depweb. state.pa.us.
C. Statutory Authority
This rulemaking is being made under the authority of sections 104(a) and 303(a) of the Land Recycling and Environmental Remediation Standards Act (Land Recycling Act) (35 P. S. §§ 6026.104(a) and 6026.303(a)), and section 1920-A of The Administrative Code of 1929 (71 P. S. § 510-20). Section 104(a) of the Land Recycling Act authorizes the Board to adopt Statewide health standards, appropriate mathematically valid statistical tests to define compliance with the Land Recycling Act and other regulations that may be needed to implement the provisions of the Land Recycling Act. Section 303(a) of the Land Recycling Act authorizes the Board to promulgate Statewide health standards for regulated substances for each environmental medium and methods used to calculate the standards. Section 1920-A authorizes the Board to formulate, adopt and promulgate rules and regulations that are necessary for the proper work of the Department.
D. Background and Purpose
The primary purpose for this proposed rulemaking is to update the standards related to cleanup of contaminated sites under the Land Recycling Act. The Land Recycling Act requires the Board to establish by regulation uniform Statewide health-based standards so that any substantial present or probable future risk to human health and the environment is eliminated. The original standards were promulgated in 1997 and codified in Chapter 250. Section 104(a) of the Land Recycling Act explicitly recognizes that these standards would need to be updated over time as better science became available and as the need for clarification or enhancement of the program became apparent. Updating the standards serves the public as the Department is able to use the most up-to-date health and scientific information to establish the cleanup standards. In addition, the changes in standards serve both the public and the regulated community as they provide clear information on what is or will be done at contaminated sites. This gives the public notice and provides remediators with a clear endpoint to the remediation process. Several amendments are currently part of guidance, but are proposed for addition to Chapter 250 to give the requirements the legal status of a binding norm, which should lead to greater consistency and clarity across this Commonwealth.
The proposal was discussed and approved with unanimous support at the Cleanup Standards Scientific Advisory Board (CSSAB) board meeting held on September 1, 2009; however, subsequent to the CSSAB's review, the Department reconsidered changes to the Statewide health standards initially considered for Methyl Tertiary Butyl Ether (MTBE) and decided not to propose any changes for MTBE at this time. The current Chapter 250 Statewide health cleanup standard for MTBE is 20 ug/l for groundwater used for drinking water. This 20 ug/l standard is the odor threshold for MTBE as published by the United States EPA in the ''2006 Edition of the Drinking Water Standards and Health Advisories'' (EPA 822-R-06-013). The Department has decided that the previously considered revisions for MTBE included in the September 1, 2009 draft, which allowed for higher concentrations of MTBE based on health based calculations, would have resulted in unacceptable taste and odor impacts on groundwater used for drinking water. The CSSAB reviewed the revised regulations on November 19, 2009, and while the CSSAB is supportive of the overall rulemaking, it opposes the standards for MTBE, as contained in the proposal, because they do not reflect specific health-based criteria from the Land Recycling Act.
E. Summary of Regulatory Requirements
§ 250.1. Definitions.
For three definitions in this section only an explanation of what the abbreviation meant was originally provided. This section has been modified to include a definition for ''EQL—Estimated Quantitation Limit,'' ''NPDES—National Pollutant Discharge Elimination System'' and ''PQL—Practical Quantitation Limit.'' A fourth definition, for ''environmental covenant,'' was added due to the passage of the Uniform Environmental Covenants Act (27 Pa.C.S. §§ 6501—6517) (UECA).
§ 250.11. Periodic Review of MSCs.
This new section describes the Department's intent to keep the medium-specific concentrations (MSCs) in Appendix A to Chapter 250 current by proposing appropriate changes based on new scientific information that relates to the basis of the MSCs at least every 3 years.
§ 250.301. Scope.
In January 2009, the EPA issued a revised methodology for calculating the risk from regulated substances at Superfund sites by developing a new document ''Risk Assessment for Superfund (RAGS), Volume I, Part F'' (RAGS). A new Subsection (b) was added to identify those regulated substances that the EPA has determined to be mutagens in the RAGS. The new methodology for calculating MSCs for these substances is described in §§ 250.306 and 250.307 (relating to ingestion numeric values; and inhalation numeric values).
§ 250.303. Aquifer determination; current use and currently planned use of aquifer groundwater.
The language of § 250.303(d)(3)(i) was modified to change the previously undefined terminology ''acknowledged within the deed'' to terminology defined under the UECA.
§ 250.304. MSCs for groundwater.
The proposed rulemaking clarifies that maximum contaminant levels (MCLs) and lifetime health advisory levels (HALs) promulgated by the Department or the EPA are immediately effective upon promulgation.
This section further clarifies the need for a remediator to address the potential intrusion of vapors from contaminated groundwater into buildings when conducting a Statewide health standard remediation under Chapter 250.
§ 250.305. MSCs for soil.
Similar to the clarification in § 250.304, this section further clarifies the need for a remediator to address the potential intrusion of vapors from contaminated soil into buildings when conducting a Statewide health standard remediation under Chapter 250.
§§ 250.306 and 250.307. Ingestion numeric values; and inhalation numeric values.
The new formulas referenced in RAGS, Volume I, Part F represent an update by the EPA of its methodology to calculate inhalation risks, originally proposed in RAGS Part A. The key difference between RAGS Part F and RAGS Part A is the use of exposure estimates (that is, air concentration metrics) that are inhalation route-specific (that is, in ug/m3) rather than ones converted to chronic ''air intake'' (that is, mg/kg-day).
The update to RAGS was necessary to ensure that the calculation of risk estimates from inhaled chemicals is consistent with EPA's currently recommended approach to developing inhalation toxicity values, that is, inhalation reference concentration (RfCi, that is, mg/m3) and inhalation unit risk (IUR, that is, (ug/m3)-1). The approach to calculating inhalation toxicity values is referenced in EPA's Inhalation Dosimetry Methodology, Methods for Derivation of Inhalation Reference Concentrations (RfCs) and Application of Inhalation Dosimetry. (United States Environmental Protection Agency, Office of Research and Development, Office of Health and Environmental Assessment, Washington, DC, EPA/600/8-90/066F, October 1994.) The methodology assumes continuous exposure and is designed so that it yields toxicity values that sufficiently cover potential age and activity related variation in inhalation exposure (RAGS, Volume I, Part F, Page A-2, Second Bullet). The exception is for chemicals that may act as mutagens and for which susceptibility is not incorporated into the IUR. A separate adjustment factor is needed where early childhood exposures are to be evaluated.
For those substances classified as mutagens, the new inhalation methodology applies Age Dependent Adjustment Factors in the calculations. These substances are identified in § 250.301(b) of the proposed regulations.
Except for the MSCs of those regulated substances that have been determined to cause cancer by a mutagenic mode of action, most of the soil and groundwater MSCs that are controlled by inhalation risks increased in value by using this new inhalation methodology. The soil and groundwater MSCs for mutagens have generally decreased in values as a result of using this new inhalation methodology
§ 250.308. Soil to groundwater pathway numeric values.
This proposed amendment corrects an omitted reference to one of the tables that contains the soil to groundwater values. No practical change in current practice is expected.
§ 250.407. Point of compliance.
This proposed change corrects a mistaken reference to soil to groundwater values on site-specific standard sites. No practical change in current practice is expected.
§ 250.605. Sources of toxicity information.
In addition to including new inhalation toxicity values (that is, inhalation reference concentration and inhalation unit risk) as required by RAGS, Volume I, Part F, the proposed changes also include an update to the hierarchy of toxicity values. This update to the hierarchy of toxicity values is necessary to comply with EPA guidance developed since the last update to Chapter 250 and titled Memorandum, Human Health Toxicity Values in Superfund Risk Assessments (OSWER Directive 9285.7-53, December 5, 2003).
§ 250.704. General attainment requirements for groundwater.
The Department recognizes that at the time of site assessment, many sites have groundwater contamination below a standard. In these cases, remediators desire the liability protection afforded by Chapter 5 of the Land Recycling Act (35 P. S. §§ 6026.501—6026.506) yet there is little scientific value in requiring additional attainment monitoring for the 8 quarters required under Subchapter G of the current regulations. The proposed change provides that the Department may consider the site assessment data as part of the information to be used to demonstrate attainment of a standard. This change fixes a problem in the construction of the rule requirements, and will allow remediators to more easily attain a standard without compromising public health.
§ 250.707. Statistical tests.
Section 250.707(b)(iii) applies to remediations where full site characterization has not been completed prior to remediation. This provision applies specifically to remediations of petroleum releases which typically result in visually observable contamination. This section provides for a reduced number of samples to demonstrate attainment, subject to a no exceedance rule rather than the application of statistical tests to demonstrate attainment. Section 250.707(b)(iv) was originally intended to fall under this provision, but as currently structured in the regulation, it applies to any remediation under the Statewide health standard. The proposed amendment places this provision within the structure of the requirements for petroleum releases without full site characterization where it was originally intended to be.
Appendix A, Tables 1—5
Since November 24, 2001, when the previous amendment was finalized, toxicology information in the references stated in § 250.605 (relating to sources of toxicity information) and physical and chemical property data listed in Table 5 have been revised for some substances. Additionally, some substances that were not listed in Tables 1—5, but that now have toxicology information available were recommended for inclusion in Tables 1—5 by the CSSAB. Some of these substances had previously been on Table 6, Threshold of Regulation MSCs; these substances have been moved to the appropriate Tables 1—5. Typographical errors were corrected.
F. Benefits, Costs and Compliance
Benefits
The Department and Board are required to update the cleanup standard concentration values and the associated toxicological data in a timely manner to assure that environmental response actions at contaminated sites are remediated based on the current EPA guidance and current toxicological information.
Meeting this responsibility in these proposed amendments assures the protection of the public health and environment relating to exposure to regulated substances where it has been determined that lower concentrations of a regulated substances are required to meet the standards established by the statute.
These proposed amendments also avoid unnecessary expense for remediators when remediating contaminated property where it has been determined that higher concentrations of regulated substances are protective and meet the standards established by the statute.
Compliance Costs
These technical amendments to this chapter will affect owners, operators and purchasers of properties and facilities who volunteer or are required to perform remediation of contaminated sites.
These changes are not expected to add any significant costs to the cleanup of contaminated sites under this program. Some cleanup standard concentration values will be lower and some will be higher. The net cost should be negligible.
Compliance Assistance Plan
The Department has regularly provided the regulated public with workshops to explain new regulations, guidance and policy. These are conducted on an average of every 1 to 2 years. Workshops will be planned to coincide with the finalization of this rule.
Paperwork Requirements
No forms or reports are required beyond those established by Act 2.
G. Pollution Prevention
As this program assumes pollution has taken place, minimizing the release is not an option. However, in remediating a site, potential sources of pollution are often removed to attain the Land Recycling Act standards, thus eliminating or minimizing the potential for future exposure to regulated substances.
H. Sunset Review
These regulations will be reviewed in accordance with the sunset review schedule published by the Department to determine whether the regulations, effectively fulfill the goals for which they were intended.
I. Regulatory Review
Under section 5(a) of the Regulatory Review Act (71 P. S. § 745.5(a)), on February 24, 2010, the Department submitted a copy of these proposed amendments to the Independent Regulatory Review Commission (IRRC) and the House and Senate Environmental Resources and Energy Committees (Committees). In addition to submitting the proposed amendments, the Department has provided IRRC and the Committees with a copy of a detailed Regulatory Analysis Form prepared by the Department. A copy of this material is available to the public upon request.
Under section 5(g) of the Regulatory Review Act, IRRC may convey any comments, recommendations or objections to the proposed amendments within 30 days of the close of the public comment period. The comments, recommendations or objections must specify the regulatory review criteria that have not been met. The Regulatory Review Act specifies detailed procedures for review of these issues by the Department, the General Assembly and the Governor prior to final publication of the regulations.
J. Public Comments
Written Comments: Interested persons are invited to submit comments, suggestions or objections regarding the proposed regulation to the Environmental Quality Board, P. O. Box 8477, Harrisburg, PA 17105-8477 (express mail: Rachel Carson State Office Building, 16th Floor, 400 Market Street, Harrisburg, PA 17101-2301). Comments submitted by facsimile will not be accepted. Comments, suggestions or objections must be received by the Board by April 5, 2010. Interested persons may also submit a summary of their comments to the Board. The summary may not exceed one page in length and must also be received by the Board by April 5, 2010. The one-page summary will be provided to each member of the Board in the agenda packet distributed prior to the meeting at which the final-form regulation will be considered.
Electronic Comments: Comments may be submitted electronically to the Board at RegComments@state.pa.us and must also be received by the Board by April 5, 2010. A subject heading of the proposal and a return name and address must be included in each transmission. If the sender does not receive an acknowledgement of electronic comments within 2 working days, the comments should be retransmitted to ensure receipt.
JOHN HANGER,
ChairpersonFiscal Note: 7-453. No fiscal impact; (8) recommends adoption.
Annex A TITLE 25. ENVIRONMENTAL PROTECTION PART I. DEPARTMENT OF ENVIRONMENTAL PROTECTION Subpart D. ENVIRONMENTAL HEALTH AND SAFETY ARTICLE VI. GENERAL HEALTH AND SAFETY CHAPTER 250. ADMINISTRATION OF LAND RECYCLING PROGRAM Subpart A. General Provisions § 250.1. Definitions.
In addition to the words and terms defined in the act, the following words and terms, when used in this chapter, have the following meanings, unless the context clearly indicates otherwise:
* * * * * EQL—Estimated quantitation limit. The lowest concentration that can be reliably achieved within specified limits of precision and accuracy during routine laboratory operating conditions. The EQL is generally 5 to 10 times the MDL (method detection limit). However, it may be nominally chosen within these guidelines to simplify data reporting. For many analytes the EQL analyte concentration is selected as the lowest non-zero standard in the calibration curve. Sample EQLs are highly matrix dependent. The EQLs in the EPA publication Test Methods for Evaluating Solid Waste, Physical/Chemical Methods [SW-846] are provided for guidance and may not always be achievable.
* * * * * Environmental covenant—A servitude arising under an environmental response project which imposes activity and use limitations.
* * * * * NPDES—National Pollutant Discharge Elimination System. The National system for the issuance of permits under section 402 of the Federal Clean Water Act (33 U.S.C.A. § 1342) including a state or interstate program which has been approved in whole or in part by the EPA.
PQL—Practical quantitation limit. The lowest limit that can be reliably achieved within specified limits of precision and accuracy under routine laboratory conditions for a specified matrix and based on quantitation, precision and accuracy, normal operation of a laboratory and the practical need in a compliance-monitoring program to have a sufficient number of laboratories available to conduct the analyses.
* * * * * § 250.11. Periodic review of MSCs.
The Department will review new scientific information that relates to the basis of the MSCs as it becomes available and will propose appropriate changes for the consideration of the EQB as necessary, but in no case more than 36 months after the effective date of the most recently promulgated MSCs.
Subchaptor C. Statewide Health Standards § 250.301. Scope.
* * * * * (b) This subchapter sets forth generic Statewide health standards for regulated substances determined by the EPA to be mutagens. Tables 1—4 contain Statewide health standards based upon the methodology for mutagens in §§ 250.306 and 250.307 (relating to ingestion numeric values; and inhalation numeric values) for the following substances classified as mutagens:
Regulated Substance CAS Number Benzo[a]anthracene 56-55-3 Benzidine 92-87-5 Benzo[a]pyrene 50-32-8 Benzo[b]fluoranthene 205-99-2 Benzo[k]fluoranthene 207-08-9 Chrysene 218-01-9 Dibenzo[a,h]anthracene 53-70-3 Dibromo-3-chloropropane, 1,2- 96-12-8 Indeno[1,2,3-cd]pyrene 193-39-5 Methylene bis(2-chloroaniline), 4,4`- 101-14-4 Nitrosodiethylamine, n- 55-18-5 Nitrosodimethylamine, n- 62-75-9 Nitroso-n-ethylurea, n- 759-73-9 Vinyl chloride 75-01-4 (c) This subchapter sets forth minimum threshold MSCs for soil and groundwater that shall be met to demonstrate attainment of the Statewide health standards for regulated substances in Appendix A, Table 6. Minimum threshold MSCs are standards developed for regulated substances for which no chemical-specific toxicological data exist.
[(c)](d)) For regulated substances which do not have an MSC for the relevant medium on Appendix A, Tables 1—4 or 6, the background standard or site-specific standard shall be met to qualify for a release of liability under the act.
§ 250.303. Aquifer determination; current use and currently planned use of aquifer groundwater.
* * * * * (d) If the Department determines that groundwater is not used or currently planned to be used, the following requirements apply within the area identified in subsection (b):
* * * * * (3) The remediator shall establish institutional controls to maintain the integrity of the nonuse aquifer determination, or include a postremediation care plan in the final report detailing the process of routinely assessing and reporting to the Department compliance with subsection (c).
(i) Postremediation care plan provisions shall be [acknowledged within the deed to the remediated property upon transfer of ownership] implemented through an environmental covenant to ensure compliance with subsection (c).
* * * * * § 250.304. MSCs for groundwater.
* * * * * (c) The MSCs for regulated substances contained in groundwater in aquifers used or currently planned to be used for drinking water or for agricultural purposes is the MCL as established by the Department or the EPA [(U. S. EPA, 1996. Drinking Water Regulations and Health Advisories] as established in § 109.202 (relating to state MCLs, MRDLs and treatment technique requirements) and Health Advisory Levels (HAL) set forth in EPA Office of Water Publication [EPA 822-R-96-001)] No. EPA 822-R-06-013. For a regulated substance where no MCL has been established, the MSC is the lifetime [health advisory level (] HAL [ )] for that compound. For a regulated substance where neither an MCL nor a lifetime HAL [is] has been established, the MSC is the lowest concentration calculated using the appropriate residential and nonresidential exposure assumptions and the equations in §§ 250.306 and 250.307 (relating to ingestion numeric values; and inhalation numeric values). New or revised MCLs or HALs promulgated by the Department or the EPA shall become effective immediately for any demonstration of attainment completed after the date the new or revised MCLs or HALs become effective.
* * * * * (h) The methodology used by the Department for calculating the MSCs for groundwater does not address the vapor intrusion exposure pathway. Therefore, to demonstrate attainment under the act for the vapor intrusion exposure pathway the remediator shall address the vapor intrusion exposure pathway in accordance with section 304(f)(4) of the act (35 P. S. § 6026.304(f)(4)) and Subchapter D (relating to site-specific standard), or in accordance with technical guidance published by the Department addressing vapor intrusion into buildings from groundwater and soil under the Statewide health standard.
§ 250.305. MSCs for soil.
* * * * * (h) The methodology used by the Department for calculating the MSCs for soil does not address the vapor intrusion exposure pathway. Therefore, to demonstrate attainment under the act for the vapor intrusion exposure pathway the remediator shall address the vapor intrusion exposure pathway in accordance with section 304(f)(4) of the act (35 P. S. § 6026.304(f)(4)) and Subchapter D (relating to site-specific standard), or in accordance with technical guidance published by the Department addressing vapor intrusion into buildings from groundwater and soil under the Statewide health standard.
(Editor's Note: For the equations that are being modified in §§ 250.306 and 250.307, the original equation is shown as being deleted in its entirety. The modified equation is shown immediately below the equation it replaces, and for clarity and ease of reading it is in normal bold type.)
§ 250.306. Ingestion numeric values.
(a) For a regulated substance which is a systemic toxicant, the ingestion numeric value for that substance was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the following equation:
(b) For a regulated substance which is a carcinogen, the ingestion numeric value for that substance was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the following [equation] equations:
(1) For regulated substances not identified as a mutagen in § 250.301(b) (relating to scope):
(2) For regulated substances identified as a mutagen, except for vinyl chloride, in § 250.301(b):
(3) For vinyl chloride:
* * * * * (d) The default exposure assumptions used to calculate the ingestion numeric values are as follows:
Residential
Nonresidential Term Systemic1 Carcinogens2,6 (Onsite Worker) THQ Target Hazard Quotient 1 N/A 1 RfDo Oral Reference Dose (mg/kg-day) Chemical-specific N/A Chemical-specific BW Body Weight (kg) N/A Soil 15 70 Groundwater 70 70 [ATDC] ATnc Averaging Time for systemic toxicants (yr) Soil 6 N/A 25 Groundwater 30 N/A 25 Abs Absorption (unitless)3 1 1 1 EF[5] Exposure Frequency (d/yr) Soil 250 250 180 Groundwater 350 350 250 ED Exposure Duration (yr) Soil 6 N/A 25 Groundwater 30 N/A 25 IngR Ingestion Rate Soil (mg/day) 100 N/A 50 GW (L/day) 2 N/A 1 CF Conversion Factor Soil (kg/mg) 1 × 10-6 1 × 10-6 1 × 10-6 GW (unitless) 1 1 1 TR Target Risk N/A 1 × 10-5 N/A [CSFo] CSFo Oral Cancer Slope Factor (mg/kg-day)-1 N/A Chemical-specific Chemical-specific [Atc] ATc Averaging Time for carcinogens (yr) N/A 70 70 [Ifadj] IFadj4 Ingestion Factor N/A Soil (mg-yr/kg-day) 57.1 17.9 GW (L-yr/kg-day) 1.1 0.4 AIFadj5 Combined Age-Dependent Adjustment Factor
and Ingestion FactorN/A N/A Soil (mg-yr/kg- day) 245 GW (L-yr/kg- day) 3.39 Notes:
1 Residential exposure to noncarcinogens is based on childhood (ages 1-6) exposure for soil, and adult exposure for groundwater, consistent with USEPA (1991).
2 Residential exposure to carcinogens is based on combined childhood and adult exposure.
3 The oral absorption factor takes into account absorption and bioavailability. In cases where the oral RfD or CSF is based on administered oral dose, the absorption factor would be limited to bioavailability. The default value is 1.
4 The Ingestion Factor for the residential scenario is calculated using the equation Ifadj = EDc × IRc/BWc + EDa × IRa/Bwa, where EDc = 6 yr, IRc = 100 mg/day for soils and 1 L/day for groundwater, BWc = 15 kg, EDa = 24 yr, IRa = 50 mg/day for soils and 2 L/day for groundwater, and BWa = 70 kg. The ingestion factor for the nonresidential scenario is calculated using the equation Ifadj = ED × IR/BW, where ED = 25 yr, IR = 50 mg/day for soils and 1 L/day for groundwater, and BW = 70 kg.
5[In cases where the inhalation RfD or CSF is based on absorbed dose, this factor can be applied in the exposure algorithm. The default value is 1 ] The Combined Age-Dependent Adjustment Factor and Ingestion Factor (AIFadj) for the residential scenario is calculated using the equation AIFadj = [ADAF<2 × ED<2 + (ADAF2-6 × ED2-6] × IRc / BWc + [(ADAF>6-16 × ED>6-16 + (ADAF>16 × ED>16)] × IRa / BWa, where ADAF<2 = 10, ED<2 = 2 yr, ADAF2-6 = 3, ED2-6 = 4 yr, IRc = 100mg/day for soils and 1 L/day for groundwater, BWc = 15 kg, ADAF>6-16 = 3, ED>6-16 = 10 yr, ADAF>16 1, ED>16 = 14 yr, IRa = 50 mg/day for soils and 2 L/day for groundwater, and BWa = 70 kg.
6 For the equation to calculate the vinyl chloride residential MSC based on the carcinogenic effect, IRc = 100 mg/day for soils and 1 L/day for groundwater, BWc = 15 kg.
* * * * * § 250.307. Inhalation numeric values.
(a) For a regulated substance which is a systemic toxicant, the following applies:
(1) For a volatile compound, the numeric value for inhalation from soil shall be calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the following equation using TF for volatiles:
(2) For a regulated substance attached to particulates, the numeric value for inhalation from soil was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the equation in paragraph (1) using TF for particulates.
(b) For a regulated substance which is a carcinogen, the following apply:
(1) For a volatile compound, the numeric value for inhalation from soil was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the following equation using TF for volatiles:
(2) For a regulated substance attached to particulates, the numeric value for inhalation from soil was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the equation in paragraph (1) using TF for particulates.
(3) For a regulated substance identified in § 250.301(b) (relating to scope) as a mutagen, except for vinyl chloride, the numeric value for inhalation from soil was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the following equation using the TF for volatiles:
(4) For vinyl chloride, the numeric value for inhalation from soil was calculated using the appropriate residential or nonresidential exposure assumptions from subsection (d) according to the following equation using the TF for volatiles:
* * * * * (d) The default exposure assumptions used to calculate the inhalation numeric values for soil are as follows:
Residential
Nonresidential Term Systemic1 Carcinogens2 (Onsite Worker) THQ Target Hazard Quotient 1 N/A 1 [RfDi] RfCi Inhal. Reference [Dose (mg/kg-day)] Concentration (mg/m3) Chemical-specific N/A Chemical-specific [BW] [Body Weight (kg)] [70] [N/A] [70] [ATnc] ATnc Averaging Time for systemic toxicants (yr) 30 N/A 25 TF Transport Factor (mg/kg)/(mg/m3)
Volatilization3
Chemical-specific
Chemical-specific
Chemical-specificParticulate4 1 × 1010 1 × 1010 1 × 1010 [Abs] [Absorption (unitless)5] [1] [1] [1] ET Exposure Time (hr/day) 24 24 8 EF Exposure Frequency[6]5 (d/yr) 250 250 180 ED Exposure Duration (yr) 30 N/A 25 CF Conversion Factor 1,000 µg/mg 1,000 µg/mg 1,000 µg/mg [IR] [Inhalation Rate (m3/hr)] [0.83] [N/A] [1.25] TR Target Risk N/A 1 × 10-5 1 × 10-5 [CSFi] IUR Inhalation [Cancer Slope Factor (mg/kg-day)]Unit Risk (µg/m3)-1 N/A Chemical-specific Chemical-specific [ATc] ATc Averaging Time for carcinogens (yr) N/A 70 70 [Ifadj] [Inhalation Factor7 (m3-yr/kg-hr)] [N/A] [0.5] [0.4] AED Combined Age-Dependent Adjustment Factor and Exposure Duration (yr)6 N/A 76 N/A Notes: Modified from USEPA Region III Risk-based Concentration Table, dated October 20, 1995.
N/A = Not Applicable
1 Residential exposure to systemic toxicants is based on adult exposure, consistent with USEPA (1991).
2 Residential exposure to carcinogens is based on combined child and adult exposure.
3 Volatilization transport factor is calculated using TF = (ER × DF)-1, where DF = 12 (mg/m3)/(m2-sec). See soil depth-specific algorithm for the calculation of ER.
4 Particulate transfer factor was calculated using TF = (ER × DF)-1, where ER = 8.25 × 10-12 (mg/m2-sec)/(mg/kg) and DF = 12(mg/m3)/(mg/m2-sec).
[5 In cases where the inhalation RfD or CSF is based on absorbed dose, this factor can be applied in the exposure algorithm. The default value is 1.]
[6]5 Assumes approximately 100 days/yr with the ground being frozen. Exposure to surficial soils when the ground is frozen is considered de minimis. The nonresidential exposure frequency is defined as 5/7 × 250 days/yr.
[7 The inhalation factor for the residential scenario is calculated using the equation IFadj = EDc × IRc/BWc + EDa × IRa/BWa, where EDc = 6 yr, IRc = 0.5 m3/hr, BWc = 15kg, EDa = 24 yr, IRa = 0.83 m3/hr, and BWa = 70 kg. The inhalation factor for the nonresidential scenario is calculated using the equation IFadj = ED × IR/BW, where ED = 25 yr, IR = 1.25 m3/hr and BW = 70 kg.]
6 The Combined Age-Dependent Adjustment Factor and Exposure Duration (AED) is calculated using the equation AED = ADAF<2 × ED<2 + ADAF2-16 × ED2-16 + ADAF>16, where ADAF<2 = 10, ED<2 = 2 yr, ADAF2-16 = 3, ED2-16 = 14 yr, ADAF>16 = 1, ED>16 = 14 yr.
* * * * * (f) For a regulated substance which is a systemic toxicant and is a volatile compound, the numeric value for the inhalation of volatiles from groundwater was calculated by using the appropriate residential or nonresidential exposure assumptions from subsection (h) according to the following equation:
(g) For a regulated substance which is a carcinogen and is a volatile compound, the numeric value for the inhalation of volatiles from groundwater shall be calculated by using the appropriate residential or nonresidential exposure assumptions from subsection (h) according to the following [equation] equations:
(1) For regulated substances not identified as a mutagen in § 250.301(b):
(2) For regulated substances identified as a mutagen, except for vinyl chloride, in § 250.301(b):
(3) For vinyl chloride:
(h) The default exposure assumptions used to calculate the inhalation numeric values for the inhalation of volatiles from groundwater are as follows:
Residential
Nonresidential Term Systemic1 Carcinogens2 (Onsite Worker) THQ Target Hazard Quotient 1 N/A 1 [RfDi] RfC Inhal. Reference [Dose (mg/kg-day)] Concentration (mg/m3) Chemical-specific N/A Chemical-specific [BW] [Body Weight (kg)] [70] [N/A] [70] [ATnc] ATnc Averaging Time for systemic toxicants (yr) 30 N/A 25 [Abs] [Absorption (unitless)3] [1] [1] [1] ET Exposure Time (hr/day) 24 24 8 EF Exposure Frequency6 (d/yr) 350 350 250 ED Exposure Duration (yr) 30 [N/A] 30 25 [IR] [Inhalation rate (m3/hr)] [0.625] [N/A] [1.25] TF Transfer Factor (L/m3)[4]3 0.5 0.5 0.5 CF Conversion Factor N/A 1,000 µg/mg 1,000 µg/mg TR Target Risk N/A 1 × 10-5 1 × 10-5 [CSFi] IUR Inhalation [Cancer Slope Factor (mg/kg-day)-1] Unit Risk (ug/m3)-1 N/A Chemical-specific Chemical-specific [ATc] ATc Averaging Time for carcinogens (yr) N/A 70 70 [IFadj] [Inhalation Factor5 (m3-yr/kg-hr)] [N/A] [0.4] [0.4] AED Combined Age-Dependent adjustment Factor and Exposure Duration (yr)4 N/A 76 N/A Notes: Modified from USEPA Region III Risk-based Concentration Table, dated October 20, 1995.
N/A = Not Applicable
1 Residential exposure to systemic toxicants is based on adult exposure, consistent with USEPA (1991).
2 Residential exposure to carcinogens is based on combined child and adult exposure.
[3 In cases where the inhalation RfD or CSF is based on absorbed dose, this factor can be applied in the exposure algorithm.]
[4]3 Default Transfer Factor is as presented in USEPA's RAGS, Part B.
5[The inhalation factor for the residential scenario is calculated using the equation IFadj = EDc × IRc/BWc + EDa × IRa/Bwa, where EDc = 6 yr, IRc = 0.5 m3/hr, BWc = 15 kg, EDa = 24 yr, IRa = 0.625 m3/hr, and BWa = 70 kg. The inhalation factor for the nonresidential scenario is calculated using the equation IFadj = ED × IR/BW, where ED = 25 yr, IR = 1.25 m3/hr and BW = 70 kg] The Combined Age-Dependent Adjustment Factor and Exposure Duration (AED) is calculated using the equation AED = ADAF <2 × ED<2 + ADAF2-16 × ED2-16 + ADAF>16 × ED>16 where ADAF<2 = 10, ED<2 + 2 yr, ADAF2-16 = 3, ED2-16 = 14 yr, ADAF>16 = 1, ED>16 = 14 yr.
§ 250.308. Soil to groundwater pathway numeric values.
(a) A person may use the soil-to-groundwater pathway numeric values listed in Appendix A, [Table] Tables 3B and 4B, as developed using the methods contained in paragraph (1), (2) or (4), may use a concentration in soil at the site which does not produce a leachate in excess of the MSC for groundwater contained in Appendix A, Tables 1 and 2, when subjected to the Synthetic Precipitation Leaching Procedure (Method 1312 of SW-846, Test Methods for Evaluating Solid Waste, promulgated by the U. S. EPA), or may use the soil-to-groundwater pathway soil buffer criteria in subsection (b) or may use the soil-to-groundwater pathway equivalency demonstration in subsection (d).
* * * * * Subchapter D. Site-Specific Standard § 250.407. Point of compliance.
* * * * * (e) [For attainment of soil-to-groundwater standards in both residential and nonresidential areas, the point of compliance is throughout the soil column.
(f) ] For the emission of regulated substances to outdoor air, the point of compliance for the air quality standard shall be as specified in the air quality regulations. See Article III (relating to air resources).
Subchapter F. Exposure And Risk Determinations § 250.605. Sources of toxicity information.
(a) For site-specific standards, the person shall use appropriate reference doses [and], reference concentrations, cancer slope factors and unit risk factors identified in Subchapter C (relating to Statewide health standards), unless the person can demonstrate that published data, available from one of the following sources, provides more current reference doses [or], reference concentrations, cancer slope factors or unit risk factors:
* * * * * (2) [Health Effects Assessment Summary Tables (HEAST).
(3)] United States Environmental Protection Agency, National Center for Environmental Assessment (NCEA) Provisional Peer-Reviewed Toxicity Values (PPRTV).
[(4) Agency for Toxic Substances and Disease Registry (ATSDR) Toxicological Profiles.
(5) California EPA, California Cancer Potency Factors.
(6) EPA criteria documents, including drinking water criteria documents, drinking water health advisory summaries, ambient water quality criteria documents and air quality criteria documents.]
(3) Other sources
(i) Health Effects Assessment Summary Tables (HEAST)
(ii) Agency for Toxic Substances and Disease Registry (ATSDR) Toxicological Profiles.
(iii) California EPA, California Cancer Potency Factors and Chronic Reference Exposure Levels.
(iv) EPA criteria documents, including drinking water criteria documents, drinking water health advisory summaries, ambient water quality criteria documents and air quality criteria documents.
* * * * * Subchapter G. Demonstration of Attainment § 250.704. General attainment requirements for groundwater.
* * * * * (d) For statistical methods under § 250.707(b)(2)(i) (relating to statistical tests), the demonstration of attainment for groundwater shall be based upon at least eight consecutive quarters of groundwater data, which may include characterization data. As an alternative, the Department may accept [four consecutive] fewer quarterly sampling events [or less] with written approval from the Department under the following conditions:
* * * * * § 250.707. Statistical tests.
* * * * * (b) The following statistical tests may be accepted by the Department to demonstrate attainment of the Statewide health standard. The statistical test for soil shall apply to each distinct area of contamination. The statistical test for groundwater will apply to each compliance monitoring well. Testing shall be performed individually for each regulated substance identified in the final report site investigation as being present at the site for which a person wants relief from liability under the act. The application of a statistical method [shall] must meet the criteria in subsection (d).
(1) For soil attainment determination at each distinct area of contamination, subparagraph (i), (ii) or (iii) shall be met in addition to the attainment requirements in §§ 250.702 and 250.703 (relating to attainment requirements; and general attainment requirements for soil).
* * * * * (iii) For sites with a petroleum release where full site characterization, as defined in § 250.204(b) (relating to final report), has not been done in association with an excavation remediation, attainment of the Statewide health standard shall be demonstrated using the following procedure:
* * * * * (B) For sites not covered by clause (A), including all sites being remediated under an NIR under this chapter, samples shall be taken from the bottom and sidewalls of the excavation in a biased fashion that concentrates on areas where any remaining contamination above the Statewide health standard would most likely be found. The samples shall be taken from these suspect areas based on visual observation and the use of field instruments. If a sufficient number of samples has been collected from all suspect locations and the minimum number of samples has not been collected, or if there are no suspect areas, the locations to meet the minimum number of samples shall be based on a random procedure. The number of sample points required shall be determined in the following way:
* * * * * (VI) For sites where there is a release to surface soils resulting in excavation of 50 cubic yards or less of contaminated soil, samples shall be collected as described in this clause, except that two samples shall be collected.
(C) All sample results shall be equal to or less than the applicable Statewide health MSC as determined using Tables 1—4 and 6 in Appendix A.
[(iv) For sites where there is a release to surface soils resulting in excavation of 50 cubic yards or less of contaminated soil, samples shall be collected as described in subparagraph (iii)(B), except that two samples shall be collected.]
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[Pa.B. Doc. No. 10-432. Filed for public inspection March 5, 2010, 9:00 a.m.]
