PURPOSE: This rule sets forth procedures and requirements for requesting and granting variances.

1. (1) Conditions of Variance. The department may grant one (1) or more variances to any water system from any maximum contaminant level (MCL) requirement, except for those MCL violations that present an acute, short-term risk to public health, or a specified treatment technique.

   1. (A) A variance from an MCL may be granted upon a finding that, due to characteristics of raw water sources which are reasonably available, the system cannot meet the MCL requirement despite application of the best available technology, treatment techniques or other means, which the department, taking cost into consideration, finds generally available; and the granting of a variance will not result in an unreasonable risk to persons served by the system.
   2. (B) A variance from a specified treatment technique may be granted upon a finding that a public water system applying for this variance has demonstrated that the treatment technique is not necessary to protect persons served by the system because of the nature of the raw water source.

2. (2) Variance Request. A supplier of water seeking a variance shall submit a written request to the department. Suppliers of water may submit a joint request for a variance when they seek similar variances under similar circumstances. Any written request for a variance shall include the following information:

   1. (A) The nature and duration of the variance requested;
   2. (B) Relevant analytical results of water quality sampling of the system including sampling of raw water relevant to the variance request;

   3. (C) Requests made under provisions of section (1) shall include:

      1. 1. Full discussion with supporting data

regarding the best available treatment technology and techniques including evidence of the inability of the system to comply, despite the application of the technology and techniques;

1. 2. Economic and legal factors relevant

to ability to comply;

1. 3. A proposed compliance schedule,

including the date each step toward compliance will be achieved;

1. 4. The date by which the connection of

an alternative raw water source or an improvement of an existing raw water source will be initiated;

1. 5. The date by which an arrangement for

an alternative raw water source or for an improvement of an existing raw water source will be completed;

1. 6. The date by which final compliance is

to be achieved;

1. 7. A plan for the provision of safe drink-

ing water should there be an excessive rise in the contaminant level for which the variance is requested; and

1. 8. A plan for interim control measures

during the effective period of variance;

1. (D) Any request made under the provisions of this rule shall include, as a condition of the variance, a statement that the system will perform monitoring and other reasonable requirements prescribed by the department;
2. (E) Any other information the applicant believes to be pertinent; and
3. (F) Other information as the department may require.

1. (3) Consideration of Variance Request. In considering whether the public water system—

   1. (A) Is unable to comply with a contam-

inant level requirement because of the nature of the raw water source, the department shall review factors it considers to be relevant, including the following:

1. 1. The availability, effectiveness and

reliability of treatment methods for the contaminant for which the variance is requested; and

1. 2. Cost and other economic considera-

tions in implementing treatment, improving the quality of the source of water or using an alternate source; and

1. (B) Should be granted a variance to a required treatment technique because the treatment is unnecessary to protect the public, the department shall consider the following factors:

   1. 1. Quality of the water source including

water quality data and pertinent sources of pollution; and

1. 2. Susceptibility of the source to con-

tamination and the source protection measures employed by the public water system.

1. (4) Disposition of a Request for Variance. If the department determines that a request for 10 CSR 60-6

a variance is inadequate or incomplete, it may deny the request.

1. (A) If the department proposes to grant a variance request submitted pursuant to section (2), it shall notify the applicant of its decision in writing. The notice shall identify the variance, the facility covered and shall specify, as appropriate, the period of time for which the variance will be effective.
2. (B) For the type of variance specified in section (1), the notice also shall provide that the variance will be terminated when the system comes into compliance with the applicable rule and may be terminated upon a finding by the department that the system has failed to comply with any requirements of a final schedule issued pursuant to 10 CSR 60- 6.030.

3. (C) For the type of variance specified in section (1), the notice shall provide for termination of the variance at any time based upon a finding that the—

   1. 1. Nature of a raw water source is that

the specified treatment technique required by the variance is necessary to protect persons; or

1. 2. Public water system has failed to

comply with monitoring and other requirements prescribed by the department as a condition to the granting of a variance.

AUTHORITY: section 640.120, RSMo (1994).* Original rule filed May 4, 1979, effective Sept. 14, 1979. Amended: Filed April 14, 1981, effective Oct. 11, 1981. Amended: Filed June 2, 1988, effective Aug. 31, 1988. Amended: Filed Dec. 4, 1990, effective July 8, 1991. Amended: Filed Feb. 1, 1996, effective Oct. 30, 1996. *Original authority 1978, amended 1989, 1992.