A. In addition to the emergency action plan (EAP) requirements in 40 CFR 257.73(a)(3) and 257.74(a)(3), the EAP shall:
- 1. Contain a notification chart showing the priority for notification in an emergency situation. The owner shall notify local emergency response agencies, affected downstream populations, county emergency management agencies, and affected flood control districts;
2. Contain a delineation of potentially unsafe conditions, evaluation procedures, and triggering events that require the initiation of partial or full emergency notification procedures, based on the urgency of the situation; including the following:
- a. Sliding of upstream or downstream slopes or abutments contiguous to the CCR surface impoundment;
- b. Sudden subsidence of the top of the CCR surface impoundment;
- c. Longitudinal or transverse cracking of the top of the CCR surface impoundment;
- d. Unusual release of water from the downstream slope or face of the CCR surface impoundment;
- e. Other unusual conditions at the downstream slope of the CCR surface impoundment;
- f. Significant landslides in the reservoir area;
- g. Increasing volume of seepage;
- h. Cloudy seepage or recent deposits of soil at seepage exit points;
- i. Sudden cracking or displacement of concrete in a concrete or masonry CCR surface impoundment spillway or outlet works;
- j. Loss of freeboard or CCR surface impoundment cross section due to storm wave erosion;
- k. Flood waters overtopping an embankment CCR surface impoundment; or
- l. Spillway backcutting that threatens evacuation of the reservoir.
- 3. Contain a specific notification procedure for each emergency situation anticipated;
- 4. Contain a description of emergency supplies and resources, equipment access to the site, and alternative means of communication.
- 5. Require the owner to submit a copy of the proposed emergency action plan for review by the Arizona Division of Emergency Management and all local emergency coordinators involved in the plan. The owner shall incorporate appropriate recommendations generated by the reviews and submit the revised emergency action plan to the Department.
- 6. Be reviewed and updated, at a minimum, every year to ensure the information is accurate and to incorporate changes such as new personnel, changing roles of emergency agencies, emergency response resources, conditions of the surface impoundment and information learned from mock exercises. The owner shall send updated portions of the plan to persons and agencies holding copies of the plan within 15 days after preparation of an update. The updated plan shall be placed in the facility’s operating record as required by § 257.105(f)(6).
- 7. Notwithstanding subsection (6) above, the owner or operator of a CCR surface impoundment may amend the written EAP at any time provided the revised plan is placed in the facility’s operating record as required by § 257.105(f)(6). The owner or operator must amend the written EAP whenever there is a change in conditions that would substantially affect the EAP in effect.
- 8. Be certified by a qualified professional engineer stating that the written EAP, and any subsequent amendment of the EAP, meets the requirements of this Article.
B. In addition to the emergency action plan requirements in §§ 257.73(a)(3) and 257.74(a)(3), as incorporated:
- 1. The owner or operator shall increase the frequency of observation when the reservoir is full, during heavy rains or flooding, and following an earthquake.
- 2. The owner or operator is responsible for the safety of the CCR surface impoundment and shall take action to lower any liquid portion of the reservoir if it appears that the impoundment has weakened or is in danger of failing.
- 3. The owner or operator of a CCR surface impoundment shall immediately notify the Department and responsible authorities in adjacent and downstream communities, including emergency management authorities, of a condition that may threaten the safety of the impoundment. The owner shall take necessary actions to protect human life and property, including action required under an emergency action plan or order issued under this Article. The owner shall report these actions to the Director as soon as possible, but not later than 12 hours after discovery of the conditions.
- 4. If CCR surface impoundment failure appears imminent, the owner or operator shall notify the county sheriff, and the Arizona Department of Public Safety or other emergency official immediately.
- 5. The owner or operator shall notify the Director immediately of any emergency condition that exists and any emergency action taken.
6. Emergency actions not impairing the safety of the CCR surface impoundment may be taken before guidance can be provided by an engineer and do not require prior approval of the Director. Emergency actions do not excuse an owner’s responsibility to promptly undertake a permanent solution. Emergency actions include:
- a. Stockpiling materials such as riprap, earth fill, sand, sandbags, and plastic sheeting.
- b. Lowering the reservoir level by making releases through the outlet or a gated spillway, by pumping, or by siphoning.
- c. Armoring eroded areas by placing sandbags, riprap, plastic sheeting, or other available material.
- d. Plugging leakage entrances on the upstream slope.
- e. Increasing freeboard by placing sandbags or temporary earth fill on the CCR surface impoundment.
- f. Diverting flood waters to prevent them from entering the reservoir basin.
- g. Constructing training berms to control flood waters.
- h. Placing sandbag ring dikes or reverse filter materials around boils at the downstream toe to provide back pressure.
- i. Removing obstructions from outlet or spillway flow areas.
- 7. Emergency actions impairing the safety of the CCR surface impoundment require prior approval of the Director. An owner shall not lower the water level by excavating the spillway or embankment unless failure is imminent.
8. The Director shall issue an emergency approval to repair, alter, or remove an existing CCR surface impoundment if the Director finds that immediate remedial action is necessary to alleviate an imminent threat to human life or property.
- a. The emergency approval shall be provided in writing.
- b. The emergency approval may contain conditions the Director determines are appropriate to protect human life or property.
- c. The emergency approval is effective immediately for 30 days after notice is issued unless extended in writing by the Director. The Director shall also send notice to the county flood control district of the county in which the CCR surface impoundment is located, all municipalities within five miles downstream of the CCR surface impoundment, and any additional persons identified in the emergency action plan.
- d. The Director may institute legal or administrative proceedings that the Director deems appropriate for violations of the emergency approval or conditions of the emergency approval.
- e. After the Director issues an emergency approval, the Department shall post information related to the approval on the Department’s CCR website as soon as practicable.
C. The requirements in this Section are based on Arizona dam safety standards additional to those in 40 CFR 257, subpart D, as incorporated in this Article, and do not apply to:
- 1. CCR surface impoundments with a maximum height of less than 6 feet, regardless of storage capacity;
- 2. CCR surface impoundments with a maximum height of between 6 and 25 feet and a storage capacity of less than 50 acre-feet; or
- 3. CCR surface impoundments with a maximum height greater than 25 feet and a storage capacity of 15 acre-feet or less.
Historical Note
New Section made by final rulemaking at 31 A.A.R. 1363 (April 25, 2025), effective date June 1, 2025 (Supp. 25-2).