Sec. 26.13.05.10-5. Variances from Secondary Containment Requirements for Tank Systems

A. The owner or operator may obtain a variance from the requirements of Regulation .10-4 of this chapter if the Secretary finds, as a result of a demonstration by the owner or operator, that:

(1) Alternative design and operating practices, together with location characteristics, will prevent the migration of any hazardous waste or hazardous constituents into the ground water and surface water at least as effectively as secondary containment during the active life of the tank system; or

(2) A substantial present or potential hazard will not be posed to human health or the environment in the event of a release that does migrate to ground water or surface water.

B. Requirements Applicable to New Tank Systems.

(1) New underground tank systems are not eligible for exemption from the secondary containment requirements of Regulation .10-4 of this chapter through a demonstration of no substantial present or potential hazard using the criteria of §E of this regulation.

(2) For the purposes of this section, a new underground tank system is an underground tank which:

(a) Cannot be entered for inspection for which construction began after July 14, 1986; or

(b) Can be entered for inspection for which construction began after July 1, 1993.

C. If the Secretary grants a variance under this regulation, the owner or operator shall construct and operate the tank system in the manner that was demonstrated to meet the requirements of §D or E of this regulation in obtaining the variance.

D. In deciding whether to grant a variance based on a demonstration of equivalent protection of ground water and surface water, the Secretary shall consider:

(1) The nature and quantity of the wastes;

(2) The proposed alternate design and operation;

(3) The hydrogeologic setting of the facility, including the thickness of soils present between the tank system and ground water; and

(4) All other factors that would influence the quality and mobility of the hazardous constituents and the potential for them to migrate to ground water or surface water.

E. In deciding whether to grant a variance based on a demonstration of no substantial present or potential hazard, as provided for in §A(2) of this regulation, the Secretary shall consider the potential adverse effects:

(1) On ground water, surface water, and land quality, taking into account:

(a) The physical and chemical characteristics of the waste in the tank system, including its potential for migration;

(b) The hydrogeological characteristics of the facility and surrounding land;

(c) The potential for health risks caused by human exposure to waste constituents;

(d) The potential for damage to wildlife, crops, vegetation, and physical structures caused by exposure to waste constituents; and

(e) The persistence and permanence of the potential adverse effects;

(2) Of a release on ground water quality, taking into account the:

(a) Quantity and quality of ground water and the direction of ground water flow;

(b) Proximity and withdrawal rates of ground water users;

(c) Current and future uses of ground water in the area; and

(d) Existing quality of ground water, including other sources of contamination and the cumulative impact of other sources of contamination on the ground water quality;

(3) Of a release on surface water quality, taking into account the:

(a) Quantity and quality of ground water and the direction of ground water flow;

(b) Patterns of rainfall in the region;

(c) Proximity of the tank system to surface waters;

(d) Current and future uses of surface waters in the area and water quality standards established for those surface waters; and

(e) Existing quality of surface water, including other sources of contamination and the cumulative impact on surface water quality; and

(4) Of a release on the land surrounding the tank system, taking into account the:

(a) Patterns of rainfall in the region; and

(b) Current and future uses of the surrounding land.

F. Procedures for Requesting a Variance. If requesting a variance from the requirements for secondary containment, the owner or operator shall:

(1) Notify the Secretary in writing of the intent to conduct and submit a demonstration for a variance from secondary containment as allowed in §§A-E of this regulation according to the following schedule:

(a) For existing tank systems, at least 24 months before the date that secondary containment shall be provided in accordance with Regulation .10-4A of this chapter; or

(b) For new tank systems, at least 30 days before entering into a contract for installation;

(2) As part of the notification required by §F(1) of this regulation, submit to the Secretary a description of the steps necessary to conduct the demonstration and a timetable for completing each of the steps;

(3) Address in the demonstration for a variance each of the factors listed in §D or E of this regulation, as appropriate; and

(4) Complete the demonstration for a variance within 180 days after notifying the Secretary of intent to conduct the demonstration.