Ariz. Admin. Code § R18-13-1001 - Applicability; Incorporation by Reference; General Provisions

A. This Article becomes effective as follows:

1. Provisions related to the submission of initial CCR permit applications, including R18-13-1010(A), R18-13-1010(B)(1), R18-13-1010(C), R18-13-1010(D), R18-13-1010(E), R18-13-1010(G), R18-13-1021(B), (D), and (E), and applicable definitions, are effective 60 days after the filing of this rule with the Secretary of State.

2. All other provisions of this Article are effective upon the date of CCR program approval.

B. Any reference or citation to 40 CFR 257, or a section thereof, appearing in the body of this Article includes any modification to the CFR or section made by this Article. When federal regulatory language that has been incorporated by reference into Arizona rule has also been amended, brackets [ ] indicate where the amended language would be placed if it was part of the federal regulation. The subsection labeling for incorporated material in this Article may not conform to the Arizona Secretary of State's formatting requirements, because the formatting reflects the structure of the incorporated federal regulation.

C. 40 CFR 257.50 through 257.53, revised as of December 14, 2020 (and no future editions) are incorporated by reference, modified by the following subsections, and on file with the Arizona Department of Environmental Quality (ADEQ) with the exception of the following:

1. 40 CFR 257.50(e) is not incorporated by reference;

2. 40 CFR 257.51 is not incorporated by reference. 40 CFR 257, subpart D was effective as federal law as provided therein, but is effective as state law, as incorporated in this Article, on the effective date of CCR program approval.

D. 40 CFR 257.53, titled "Definitions", is amended as follows:

1. "New CCR surface impoundment" means:

a. In the places listed below, a CCR surface impoundment that begins construction or operation after the effective date of these rules:

i. R18-13-1002(B), (C), and (D);

ii. R18-13-1003.01;

iii. R18-13-1004(B), (C) and (D);

iv. R18-13-1010(D)(11);

v. R18-13-1010.01; and

vi. R18-13-1017(E).

b. Other than as listed in paragraph (a), a CCR surface impoundment or lateral expansion of an existing or new CCR surface impoundment that first receives CCR or commences construction after October 19, 2015. A new CCR surface impoundment has commenced construction if the owner or operator has obtained the federal, state, and local approvals or permits necessary to begin physical construction and a continuous on-site, physical construction program had begun after October 19, 2015.

2. "Participating State" means Arizona, after CCR program approval.

3. "Participating State Director" means the Director of ADEQ, after CCR program approval.

4. "Qualified professional engineer" means an individual who is licensed by the state of Arizona as a Professional Engineer to practice one or more disciplines of engineering and who is qualified by education, technical knowledge and experience to make the specific technical certifications required under this Article. An engineer is considered qualified to provide information to the Director regarding the safe storage level of a reservoir if the engineer:

a. Is licensed in accordance with A.R.S. Title 32, Chapter 1, with proficiency in engineering and knowledge of dam technology,

b. Has three years of experience in the field of dam safety, and

c. Has actual experience in conducting dam safety inspections.

5. "State" means Arizona.

E. In addition to the definitions in 40 CFR 257.53:

1. "ADEQ" or "Department" means the Arizona Department of Environmental Quality.

2. "Applicable requirement" means a requirement in A.R.S. Title 49, Chapter 4, this Article, or Article 17, to which an owner or operator is subject based on the applicability criteria in these laws.

3. "CCR multi-unit" means a group of CCR units operating with a multi-unit groundwater monitoring system complying with 40 CFR 257.91(d).

4. "CCR program approval" means United States Environmental Protection Agency approval of the Arizona coal combustion residuals program in accordance with 42 United States Code section 6945(d)(1).

5. "Certification from a qualified professional engineer or approval from the Participating State Director or approval from EPA where EPA is the permitting authority" means "certification from a qualified professional engineer, approved by the Director or EPA where EPA is the permitting authority", unless specifically provided otherwise.

6. "Director" or "State Director" means the director of ADEQ.

7. "Discharge" has the same meaning prescribed in A.R.S. § 49-201.

8. "EPA" means the United States Environmental Protection Agency.

F. The following definitions are also applicable in this Article:

1. "Appurtenant structure" means any structure that is contiguous and essential to the safe operation of the CCR surface impoundment including embankments, saddle dikes, outlet works and controls, diversion ditches, spillway and controls, access structures, bridges, and related housing at a surface impoundment.

2. "Emergency spillway" means a spillway designed to safely pass the inflow design flood routed through the reservoir. If the flow is controlled by gates, it is a controlled spillway. If the flow is not controlled by gates, it is an uncontrolled spillway.

3. "Incremental adverse consequences" means under the same loading conditions, the additional adverse consequences such as economic, intangible, lifeline, or human losses, that would occur due to the failure or improper operation of the CCR surface impoundment over those that would have occurred without failure or improper operation of the CCR surface impoundment.

4. "Intangible losses" means incremental adverse consequences to property that are not economic in nature, including property related to social, cultural, unique, or resource-based values, including the loss of irreplaceable and unique historic and cultural features; long-lasting pollution of land or water; or long-lasting or permanent changes to the ecology, including fish and endangered species habitat identified and evaluated by a public natural resource management or protection agency.

5. "Maximum credible earthquake" means the most severe earthquake that is believed to be possible at a point on the basis of geologic and seismological evidence.

6. "Maximum water surface" means the maximum elevation of the reservoir water level attained during routing of the inflow design flood.

7. "Outlet works" means a closed conduit under or through a CCR surface impoundment or through an abutment for the controlled discharge of the contents normally impounded by a CCR surface impoundment and reservoir. The outlet works include the inlet and outlet structures appurtenant to the conduit. Outlet works may be controlled or uncontrolled.

8. "Probable maximum flood" or "PMF" means the flood runoff expected from the most severe combination of critical meteorologic and hydrologic conditions that are reasonably possible in the region, including rain and snow where applicable. 0.5 PMF is that flood represented by the flood hydrograph with ordinates equal to 0.5 the corresponding ordinates of the PMF hydrograph.

9. "Probable maximum precipitation" means the greatest depth of precipitation for a given duration that is theoretically physically possible over a particular size storm area at a particular geographical location at a particular time of year.

10. "Reservoir" means a CCR surface impoundment.

11. "Residual freeboard" or "freeboard" means the vertical distance between the highest water surface elevation during the inflow design flood and the lowest point at the top of the CCR surface impoundment.

12. "Safe storage level" means the maximum reservoir surface elevation at which the Director determines it is safe to impound water, other liquids, or CCR in the reservoir.

13. "Safety deficiency" means a condition at a CCR surface impoundment that impairs or adversely affects the safe operation of the CCR surface impoundment.

14. "Spillway crest" means the highest elevation of the floor of the spillway along a centerline profile through the spillway.

15. "Storage capacity" means the maximum volume of CCR, liquid, sediment, or debris that can be impounded in the reservoir with no discharge, including the situation where an uncontrolled outlet becomes plugged. When spillways are present, the storage capacity is reached when the reservoir level is at the crest of the emergency spillway, or at the top of permanently mounted emergency spillway gates in the closed position. Storage capacity excludes dead storage below the natural ground surface.

16. "Total freeboard" means the vertical distance between the emergency spillway crest or the safe storage level and the top of the CCR surface impoundment.

17. "Unsafe" means that safety deficiencies in a CCR surface impoundment or spillway could result in failure of the CCR surface impoundment with subsequent loss of human life or significant property damage.

Notes

Ariz. Admin. Code § R18-13-1001

New section made by final rulemaking at 31 A.A.R. 1363, effective 6/1/2025.