TITLE 18. ENVIRONMENTAL QUALITY

Historical Note

Adopted as an emergency effective December 5, 1986, pursuant to A.R.S. § 41-1003, valid for only 90 days (Supp. 86-6). Emergency expired. Adopted, without change, as an emergency effective March 6, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-1). Emergency expired. Former Section R9-20-102 was renumbered as Section R18-7-101, amended and readopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-101 repealed; new Section renumbered from R18-7-110; both by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Summary renumbering action revoked; former numbering of Sections R18-7-101 and R18-7-110 restored effective January 22, 1999. Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

R18-7-102. Repealed

Historical Note

Adopted as an emergency effective December 5, 1986, pursuant to A.R.S. § 41-1003, valid for only 90 days (Supp. 86-6). Emergency expired. Amended and adopted as an emergency effective March 6, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-1). Emergency expired. Former Section R9-20-104 was renumbered as Section R18-7-102, amended and readopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-102 repealed by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

R18-7-103. Repealed

Historical Note

Adopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-103 repealed by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

R18-7-104. Repealed

Historical Note

Adopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-104 repealed by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

R18-7-105. Repealed

Historical Note

Adopted as an emergency effective December 5, 1986, pursuant to A.R.S. § 41-1003, valid for only 90 days (Supp. 86-6). Emergency expired. Amended and adopted as an emergency effective March 6, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-1). Emergency expired. Former Section R9-20-105 was renumbered as Section R18-7-105, amended and readopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-105 repealed by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

R18-7-106. Repealed

Historical Note

Adopted as an emergency effective December 5, 1986, pursuant to A.R.S. § 41-1003, valid for only 90 days (Supp. 86-6). Emergency expired. Amended and adopted as an emergency effective March 6, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-1). Emergency expired. Former Section R9-20-106 was renumbered as Section R18-7-106, amended and readopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-106 repealed by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

R18-7-107. Repealed

Historical Note

Adopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-107 repealed by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

R18-7-108. Repealed

Historical Note

Adopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-108 repealed by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

Editor's Note: Emergency amendment R18-7-109, removed in Supp. 97-3, was reinstated at the request of the Department. Refer to Supp. 97-1 for emergency rule. This Section was subsequently amended under the regular rulemaking process effective (Supp. 97-4). This Section was repealed by summary action (Supp. 98-4).

R18-7-109. Repealed

Historical Note

Adopted as an emergency effective December 6, 1986, pursuant to A.R.S. § 41-1003 valid for only 90 days. Emergency expired. Amended and adopted as an emergency effective March 6, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-1). Emergency expired. Former Section R9-20-111 was renumbered as Section R18-7-109, amended and readopted as an emergency effective June 18, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). Section amended by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Amendment adopted permanently effective December 4, 1997 (Supp. 97-4). R18-7-109 repealed by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Adopted summary rules filed August 10, 1999; interim effective date of January 22, 1999 now the permanent effective date (Supp. 99-3).

R18-7-110. Expired

Historical Note

Adopted as an emergency effective June 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-2). Emergency expired. Readopted without change as an emergency effective September 17, 1987, pursuant to A.R.S. § 41-1026, valid for only 90 days (Supp. 87-3). Emergency expired. Amended and adopted as a permanent rule effective December 22, 1987 (Supp. 87-4). R18-7-110 renumbered by summary action with an interim effective date of January 22, 1999; filed in the Office of the Secretary of State December 29, 1998 (Supp. 98-4). Summary renumbering action revoked; former numbering of Sections R18-7-101 and R18-7-110 restored effective January 22, 1999 (Supp. 99-3). Section expired under A.R.S. § 41-1056(E) at 8 A.A.R. 4298, effective August 31, 2002 (Supp. 02-3).

Editor's Note: Emergency adopted Article 2 removed in Supp. 97-3, was reinstated at the request of the Department. Refer to Supp. 97-1 for emergency Sections. New Sections were subsequently adopted under the regular rulemaking process (Supp. 97-4).

ARTICLE 2. SOIL REMEDIATION STANDARDS

R18-7-201. Definitions

In addition to the definitions provided in A.R.S. §§ 49-151 and 49-152, the following definitions apply in this Article:

1. "Aquifer Protection Permit Program" means the system of requirements prescribed in A.R.S. Title 49, Chapter 2, Article 3 and A.A.C. Title 18, Chapter 9, Articles 1 through 7.

2. "Background" means a concentration of a naturally occurring contaminant in soils.

3. "Carcinogen" or "carcinogenic" means the potential of a contaminant to cause cancer in humans as determined by lines of evidence in accordance with a narrative classification in "Guidelines for Carcinogen Risk Assessment", EPA/630/P-03/001F, March 2005, (and no future editions), which is incorporated by reference. "Guidelines for Carcinogen Risk Assessment" is available from ADEQ and at http://cfpub.epa.gov/ncea/raf/recordisplay.cfm?deid=116283.

4. "Child care facility" means any permanent facility on a property or portion of property in which care or supervision is provided for children below the age of 18, unaccompanied by a parent or guardian, for periods of less than 24 hours per day. Child care facility does not include private homes or facilities that care for fewer than five children.

5. "Contact" means exposure to a contaminant through ingestion, inhalation, or dermal absorption.

6. "Contaminant" means a substance regulated by the programs listed in R18-7-202(A) or R18-7-202(B) or defined in A.R.S. § 49-171(2).

7. "Department" means the Arizona Department of Environmental Quality.

8. "Deterministic risk assessment methodology" means a site-specific human health risk assessment, performed using a specific set of input variables, exposure assumptions, and toxicity criteria, represented by point estimates for each receptor evaluated, which results in a point estimate of risk.

9. "Declaration of Environmental Use Restriction" or "DEUR" means a restrictive covenant as described in A.R.S. § 49-152.

10. "Ecological community" means an assemblage of populations of different species within a specified location in space and time.

11. "Ecological receptor" means a specific ecological community, population, or individual organism, protected by federal or state laws and regulations, or a local population that provides an important natural or economic resource, function, and value.

12. "Ecological risk assessment" means a scientific evaluation of the probability of an adverse effect to ecological receptors from exposure to specific types and concentrations of contaminants. An ecological risk assessment contains four components: identification of potential contaminants; an exposure assessment; a toxicity assessment; and a risk characterization.

13. "Engineering control" means a remediation method, such as a barrier or cap, which is used to prevent or minimize exposure to contaminants, and includes technologies that reduce the mobility or migration of contaminants.

14. "Excess lifetime cancer risk" means the increased risk of developing cancer above the background cancer occurrence levels due to exposure to contaminants.

15. "Exposure" means contact between contaminants and organisms.

16. "Exposure pathway" means the course a contaminant takes from a source to an exposed organism. Each exposure pathway includes a source or release from a source, an exposure point, and an exposure route. If the exposure point differs from the source, transport/exposure media (that is, air, water) are also included.

17. "Exposure point" means a location of potential contact between a contaminant and an organism.

18. "Exposure route" means the way a contaminant comes into contact with an organism (that is, by ingestion, inhalation, or dermal contact).

19. "Groundwater" means water in an aquifer as defined in A.R.S. § 49-201(2).

20. "Hazard Index" means the sum of hazard quotients for multiple substances and/or multiple exposure pathways, or the sum of hazard quotients for chemicals acting by a similar mechanism and/or having the same target organ.

21. "Hazardous Waste Management Program" means the system of requirements prescribed in A.R.S. Title 49, Ch. 5, Article 2 and 18 A.A.C. 8, Article 2.

22. "Hazard quotient" means the value which quantifies non-carcinogenic risk for one chemical for one receptor population for one exposure pathway over a specified exposure period. The hazard quotient is equal to the ratio of a chemical-specific intake to the reference dose.

23. "Imminent and substantial endangerment to the public health or the environment" has the meaning found in A.R.S. § 49-282.02(C)(1).

24. "Institutional control" means a legal or administrative tool or action taken to reduce the potential for exposure to contaminants.

25. "Letter of Completion" means a Departmental statement that indicates whether the property in question has met the soil remediation standards in this Article.

26. "Migrate" or "migration" means the movement of contaminants from the point of release, emission, discharge, or spillage: through the soil profile; by volatilization from soil to air and subsequent dispersion to air; and by water, wind, or other mechanisms.

27. "Non-carcinogen" means a contaminant that has the potential upon exposure to an individual to cause adverse health effects other than cancer.

28. "Non-residential site-specific remediation level" means a level of contaminants remaining in soil after remediation that results in a cumulative excess lifetime cancer risk between 1 x 10 -6 and 1 x 10 -4 and a Hazard Index no greater than 1 based on non-residential exposure assumptions.

29. "Nuisance" means the activities or conditions that may be subject to A.R.S. § 49-141.

30. "Person" means any public or private corporation, company, partnership, firm, association, or society of persons, the federal government and any of its departments or agencies, this state or any of its agencies, departments, political subdivisions, counties, towns, municipal corporations, as well as a natural person.

31. "Population" means an aggregate of individuals of a species within a specified location in space and time.

32. "Probabilistic risk assessment methodology" means a site-specific human health risk assessment, performed using probability distributions of input variables and exposure assumptions that take into account the variability and uncertainty of these values, which results in a range or distribution of possible risk estimates.

33. "Reasonable Maximum Exposure" or "RME" means the highest human exposure case that is greater than the average, but is still within the range of possible exposures to humans at a site.

34. "Remediate" or "remediation" has the meaning found in A.R.S. § 49-151.

35. "Reference dose" means the toxicity factor expressed as a threshold level in units of (mg/kg-day) at which non-cancer effects are not expected to occur.

36. "Repository" means the Department's database, established under A.R.S. § 49-152(E), from which the public may view information pertaining to remediation projects.

37. "Residential site-specific remediation level" means a level of contaminants remaining in the soil after remediation that results in a cumulative excess lifetime cancer risk between 1 x 10 -6 and 1 x 10 -4 and a Hazard Index no greater than 1 based on residential exposure assumptions.

38. "Residential use" has the meaning found in A.R.S. § 49-151.

39. "School" means any public institution under the jurisdiction of the Arizona State Board of Education or the Arizona State Board for Charter Schools, or any non-public institution, established for the purposes of offering instruction to children attending any grade from preschool through grade 12.

40. "Site-specific human health risk assessment" means a scientific evaluation of the probability of an adverse effect to human health from exposure to specific types and concentrations of contaminants. A site-specific human health risk assessment contains four components: identification of potential contaminants; an exposure assessment; a toxicity assessment; and a risk characterization.

41. "Soil" means all earthen materials, including moisture and pore space contained within earthen material, located between the land surface and groundwater including sediments and unconsolidated accumulations produced by the physical and chemical disintegration of rocks.

42. "Soil remediation level" or "SRL" means a pre-determined risk-based standard based upon the total contaminant concentration in soil, developed pursuant to A.R.S. § 49-152(A)(1) and listed in Appendix A or, as applicable, in Appendix B.

43. "Solid Waste Management Program" means the system of requirements prescribed in A.R.S. Title 49, Ch. 4, and the rules adopted under those statutes.

44. "Special Waste Management Program" means the system of requirements prescribed in A.R.S. Title 49, Ch. 4, Article 9 and 18 A.A.C. 13, Articles 13 and 16.

45. "Underground Storage Tank Program" or "UST Program" means the system of requirements prescribed in A.R.S. Title 49, Ch. 6, Article 1 and 18 A.A.C. 12.

46. "Water Quality Assurance Revolving Fund" or "WQARF" means the system of requirements prescribed in A.R.S. Title 49, Ch. 2, Article 5 and 18 A.A.C. 16.

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-201 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Amended by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-202. Applicability

A. This Article applies to a person legally required to conduct soil remediation by any of the following regulatory programs administered by the Department:

1. The Aquifer Protection Permit Program.

2. The Hazardous Waste Management Program.

3. The Solid Waste Management Program.

4. The Special Waste Management Program.

5. The Underground Storage Tank Program.

6. The Water Quality Assurance Revolving Fund.

7. Any other program under A.R.S. Title 49 that regulates soil remediation.

B. This Article also applies to a person who is not legally required to conduct soil remediation, but who chooses to do so under any program administered by the Department.

C. The requirements of this Article apply in addition to any specific requirements of the programs described in subsections (A) or (B).

D. This Article is limited to soil remediation.

E. A person who is remediating a site shall comply with the numeric soil remediation standards identified in either Appendix A or Appendix B if both of the following conditions are met. If either subsection (1) or subsection (2) is not met, a person who is remediating a site shall comply with the numeric soil remediation standards identified in Appendix A.

1. The site was characterized before May 5, 2007. A site is considered characterized when the laboratory analytical results of the soil samples delineating the nature, degree, and extent of soil contamination have been received by the person conducting the remediation.

2. The site was remediated or a risk assessment completed before May 5, 2010. A risk assessment or remediation is considered completed when site closure, that meets the conditions in R18-7-209, has been requested.

F. Nothing in this Article limits the Department's authority to establish more stringent soil remediation levels in response to:

1. A nuisance.

2. An imminent and substantial endangerment to the public health or the environment.

G. This Article does not apply to persons remediating soil to numeric soil remediation levels specified in the following documents and entered into, issued, or approved before May 5, 2007:

1. Orders of the Director;

2. Orders of any Court;

3. Work agreements approved by the Director pursuant to A.R.S. § 49-282.05;

4. Closure plans approved by the Director pursuant to R18-8-265;

5. Post-closure permits approved by the Director pursuant to R18-8-270;

6. Records of Decision approved by the Director pursuant to R18-16-410;

7. Records of Decision approved by the Director pursuant to R18-16-413; and

8. Records of Decision approved by the Director pursuant to 40 CFR 300.430(f)(5).

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-202 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Amended by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-203. Remediation Standards

A. A person subject to this Article shall remediate soil so that any concentration of contaminants remaining in the soil after remediation is less than or equal to one of the following:

1. The background remediation standards prescribed in R18-7-204.

2. The pre-determined remediation standards prescribed in R18-7-205.

3. The site-specific remediation standards prescribed in R18-7-206.

B. A person who conducts a soil remediation based on the standards in R18-7-205, R18-7-206, R18-7-207 shall remediate soil so that any concentration of contaminants remaining in the soil after remediation does not:

1. Cause or threaten to cause a violation of Water Quality Standards prescribed in 18 A.A.C. 11. If the remediation level for a contaminant in the soil is not protective of aquifer water quality and surface water quality, the person shall remediate soil to an alternative soil remediation level that is protective of aquifer water quality and surface water quality.

2. Exhibit a hazardous waste characteristic of ignitability, corrosivity, or reactivity as defined in R18-8-261(A). If the remediation level for a contaminant in the soil results in leaving soils that exhibit a hazardous waste characteristic other than toxicity, the person shall remediate soil to an alternative soil remediation level such that the soil does not exhibit a hazardous waste characteristic other than toxicity.

3. Cause or threaten to cause an adverse impact to ecological receptors. If the Department determines that the remediation level for a contaminant in soil may impact ecological receptors based on the existence of ecological receptors and complete exposure pathways, the person shall conduct an ecological risk assessment. If the ecological risk assessment indicates that any concentration of contaminants remaining in the soil after remediation causes or threatens to cause an adverse impact to ecological receptors, the person shall remediate soil to an alternative soil remediation level, derived from the ecological risk assessment, that is protective of ecological receptors.

C. Soil vapor concentration may be used to estimate the total contaminant concentration in soil if the Department determines that the soil vapor concentration methodology will not be invalidated by the soil, hydrogeology, or other characteristics of the site.

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 59; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-203 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Amended by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-204. Background Remediation Standards

A. A person may elect to remediate to a background concentration for a contaminant.

B. A person who conducts a remediation to a background concentration for a contaminant shall establish the background concentration using all of the following factors:

1. Site-specific historical information concerning land use.

2. Site-specific sampling of soils unaffected by a release, but having characteristics similar to those of the soils affected by the release.

3. Statistical analysis of background concentrations using the 95th percentile upper confidence limit.

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-204 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Amended by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-205. Pre-determined Remediation Standards

A. A person may elect to remediate to the residential or non-residential soil remediation levels (SRLs) in Appendix A. If allowed under R18-7-202(E), a person may also elect to remediate to the residential or non-residential SRLs in Appendix B.

B. A person who conducts remediation pursuant to this Article shall remediate to the residential SRL on any property where there is residential use at the time remediation is completed.

C. A pre-determined contaminant standard established by federal law or regulation may be used for polychlorinated biphenyl cleanups regulated pursuant to the Toxic Substances Control Act (TSCA) at 40 CFR 761.120 et seq., however, the Department has no regulatory authority to issue a Letter of Completion in TSCA-regulated cleanups.

D. A person who elects to utilize a residential or non-residential SRL for the following known human carcinogens shall remediate to a 1 x 10-6 excess lifetime cancer risk: benzene, benzidine, bis (chloromethyl) ether, chromium VI, diethylstilbestrol, direct black 38, direct blue 6, direct brown 95, nickel subsulfide, and vinyl chloride.

E. Except as provided below, a person who elects to remediate to a residential SRL may utilize a 1 x 10-5 excess lifetime cancer risk for any carcinogen other than a known human carcinogen. If the current or currently intended future use of the contaminated site is a child care facility or school where children below the age of 18 are reasonably expected to be in frequent, repeated contact with the soil, the person conducting remediation shall remediate to a 1 x 10-6 excess lifetime cancer risk.

F. For contaminants that exhibit both carcinogenic and non-carcinogenic effects, the numeric standard that is lower (more protective) shall apply.

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-205 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Amended by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-206. Site-specific Remediation Standards

A. A person may elect to remediate to a residential or a non-residential site-specific remediation level derived from a site-specific human health risk assessment.

B. A person who conducts a remediation to a residential or a non-residential site-specific remediation level shall use one of the following site-specific human health risk assessment methodologies:

1. A deterministic methodology. If a deterministic methodology is used, reasonable maximum exposures shall be evaluated for future use scenarios.

2. A probabilistic methodology. If a probabilistic methodology is used, it shall be no less protective than the 95th percentile upper bound estimate of the distribution.

3. An alternative methodology commonly accepted in the scientific community. An alternative methodology is considered accepted in the scientific community if it is published in peer-reviewed literature, such as a professional journal or publication of standards of general circulation, and there is general consensus within the scientific community that the methodology is sound.

C. A person who conducts a remediation to a site-specific remediation level shall remediate to the residential site-specific remediation level on any property where there is residential use at the time remediation is completed.

D. A person conducting a remediation to a residential or a non-residential site-specific remediation level shall remediate the contaminants in soil to a Hazard Index no greater than 1 and a cumulative excess lifetime cancer risk from 1 x 10-6 to 1 x 10-4. The following site-specific factors shall be evaluated when determining the cumulative excess lifetime cancer risk:

1. The presence of multiple contaminants.

2. The existence of multiple pathways of exposure.

3. The uncertainty of exposure.

4. The sensitivity of the exposed population.

5. Other program-related laws and regulations that may apply.

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-206 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Amended by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-207. Site-specific Remediation Standards for Nitrates and Nitrites

A person who conducts remediation of nitrates or nitrites shall remediate to a site-specific remediation level pursuant to R18-7-203(B)(1), (2), and (3).

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-207 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Section repealed; new Section made by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-208. Declaration of Environmental Use Restriction (DEUR)

A property owner who elects to leave contamination on a property that exceeds the applicable residential standard for the property under R18-7-205 or R18-7-206, or elects to use an institutional control or an engineering control to meet the requirements of R18-7-205, R18-7-206, or R18-7-207, shall record a DEUR pursuant to A.R.S. § 49-152 and comply with the related provisions of that statute and applicable rules.

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-208 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Former R18-7-208 renumbered to R18-7-209; new R18-7-208 made by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-209. Letter of Completion or Alternative Closure Document

A. If a person requests a Letter of Completion or an alternative closure document, a person shall submit, at a minimum, the following information to the applicable Departmental program listed in R18-7-202(A) or described in R18-7-202(B):

1. A description of the actual activities, techniques, and technologies used to remediate soil at the site, including the legal mechanism in place to ensure that any institutional and engineering controls are maintained.

2. Documentation that requirements prescribed in R18-7-203(A) and R18-7-203(B)(1) and (2) have been satisfied.

3. If the Department determines pursuant to R18-7-203(B)(3) that an ecological risk assessment is required, documentation that the requirements prescribed in R18-7-203(B)(3) have been satisfied.

4. Soil sampling analytical results that are representative of the area remediated, including documentation that the laboratory analysis of samples has been performed by a laboratory licensed by the Arizona Department of Health Services under A.R.S. § 36-495 et seq. and 9 A.A.C. 14, Article 6.

5. A statement signed by the person conducting the remediation certifying the following: I certify under penalty of law that this document and all attachments are, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of a fine and imprisonment for knowing violations.

B. The applicable Departmental program described in R18-7-202(A) or R18-7-202(B) shall evaluate the information described in R18-7-209(A). The Department may request additional information, or if the Department verifies compliance with the soil remediation standards set forth under this Article and closure requirements of the applicable program or programs identified in R18-7-202(A) or described in R18-7-202(B), the Department shall issue a Letter of Completion, or an alternative closure document provided for by statute or rule that certifies the soil standards in this Article have been achieved.

C. The applicable Departmental program described in R18-7-202(A) or R18-7-202(B) may revoke or amend any Letter of Completion or alternative closure document described in R18-7-209(B) if any of the information submitted pursuant to R18-7-208 or R18-7-209(A) is inaccurate or if any condition was unknown to the Department when the Department issued the Letter of Completion or alternative closure document.

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-208 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Former R18-7-209 renumbered to R18-7-210; new R18-7-209 renumbered from R18-7-208 and amended by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

R18-7-210. Notice of Remediation and Repository

A. A person conducting soil remediation shall submit a Notice of Remediation to the applicable Departmental program listed in R18-7-202(A) or R18-7-202(B) before beginning remediation. A person conducting a soil remediation to address an immediate and substantial endangerment to public health or the environment and who has notified the Department in accordance with notification requirements prescribed in A.R.S. § 49-284 is not required to submit a Notice of Remediation before beginning remediation. Any person who continues soil remediation after the immediate and substantial endangerment has been abated shall submit a Notice of Remediation. A Notice of Remediation shall include all of the following information:

1. The name and address of the real property owner;

2. The name and address of the remediating party;

3. A legal description and street address of the property;

4. A list of each contaminant to be remediated;

5. The background concentration, SRL, or site-specific remediation level selected to meet the remediation standards;

6. A description of the current and post-remediation property use as either residential or non-residential;

7. The rationale for the selection of residential or non-residential remediation; and

8. The proposed technologies for remediating the site.

B. The Department shall maintain a repository available to the public for information regarding sites where soil is remediated. The Repository shall include a listing of sites for which a Notice of Remediation has been submitted or a Letter of Completion or alternative closure document has been issued.

1. For sites where a Notice of Remediation has been filed, the Repository shall contain the date the notice was filed and the information submitted as described in subsection (A).

2. For sites where a Letter of Completion or alternative closure document has been issued, the Repository shall contain the following:

a. The name and address of the real property owner;

b. The name and address of the remediating party;

c. A legal description and street address of the property;

d. A listing of each contaminant that was remediated;

e. The background concentration, SRL, or site-specific remediation level selected to meet the remediation standard;

f. A description whether the residential or non-residential standard was achieved;

g. A description of any engineering or institutional control used to remediate the site; and

h. The date when the Letter of Completion or alternative closure document was issued.

Historical Note

Adopted by emergency action effective March 29, 1996, pursuant to A.R.S. § 41-1026 and Laws 1995, Ch. 232, § 5; in effect until permanent rules are adopted and in place no later than August 1, 1997, pursuant to A.R.S. § 49-152 and Laws 1995, Ch. 232, § 5 (Supp. 96-1). Historical note revised to clarify exemptions of emergency adoption (Supp. 97-1). Interim emergency amendment reinstated at the request of the Department (see Supp. 97-1); historical note from Supp. 97-3 stating emergency expired removed for clarity. Section R18-7-208 adopted permanently effective December 4, 1997, replacing emergency rule (Supp. 97-4). Section R18-7-210 renumbered from R18-7-209 and amended by final rulemaking at 13 A.A.R. 971, effective May 5, 2007 (Supp. 07-1).

Appendix A. Soil Remediation Levels (SRLs)