Sec. 26.13.05.06-2. General Ground Water Monitoring Requirements

For any ground water monitoring program developed to satisfy Regulation .06-4, .06-5, or .06-6 of this chapter, the owner or operator shall:

A. Obtain approval of the Secretary before installation;

B. Ensure that the ground water monitoring system:

(1) Consists of a sufficient number of wells, installed at appropriate locations and depths, to yield ground water samples from the uppermost aquifer that represent the quality of background ground water that has not been affected by leakage from a regulated unit; and

(2) Satisfies the following conditions if the determination of background water quality includes sampling of wells that are not hydraulically upgradient of the waste management area:

(a) Hydrogeologic conditions do not allow the owner or operator to determine what wells are hydraulically upgradient; and

(b) Sampling at other wells will provide an indication of background ground water quality that is as representative as, or more representative than, that provided by the upgradient wells;

C. Ensure that the ground water monitoring system:

(1) Represents the quality of ground water passing the point of compliance; and

(2) Allows for the detection of contamination when hazardous waste or hazardous constituents have migrated from the waste management area to the uppermost aquifer;

D. Ensure that separate ground water monitoring systems are provided for each regulated unit unless other provisions for sampling the ground water in the uppermost aquifer will enable detection and measurement at the compliance point of hazardous constituents from the regulated units that have entered the ground water in the uppermost aquifer;

E. Ensure that installation of the ground water monitoring system is:

(1) Approved by an individual who has:

(a) A bachelor's degree in geology or a related field of earth science from an accredited college or university; and

(b) At least 3 years experience in the design and installation of these systems; and

(2) Conducted in accordance with the requirements of COMAR 26.04.04;

F. Ensure that each monitoring well meets all of the following requirements:

(1) The well is cased in a manner that maintains the integrity of the monitoring well bore hole;

(2) The casing is screened or perforated and packed with gravel or sand, when necessary, to enable collection of ground water samples; and

(3) The annular space, that is, the space between the bore hole and well casing, above the sampling depth, is sealed to prevent contamination of samples and the ground water;

G. Ensure that the ground water monitoring program includes consistent sampling and analysis procedures that are designed to provide a reliable indication of ground water quality below the waste management area by including, at a minimum, procedures and techniques for:

(1) Sample collection;

(2) Sample preservation and shipment;

(3) Analytical procedures; and

(4) Chain of custody control;

H. Ensure that the ground water monitoring program includes sampling and analytical methods that are appropriate for ground water sampling and that accurately measure hazardous constituents in ground water samples;

I. Ensure that the ground water monitoring program includes a determination of the ground water surface elevation each time ground water is sampled;

J. Satisfy the following conditions in implementing the detection monitoring program as required by Regulation .06-4 of this chapter or in implementing the compliance monitoring program as required by Regulation .06-5 of this chapter:

(1) Collect data on each hazardous constituent specified in the permit to be collected from background wells and wells at the compliance point or points;

(2) Ensure that the number and kinds of samples collected by the owner or operator to establish the background are appropriate for the form of statistical test employed, following generally accepted statistical principles;

(3) Ensure that the sample size is as large as necessary to assure with reasonable confidence that a contaminant release to ground water from a facility will be detected; and

(4) Determine an appropriate sampling procedure and interval for each hazardous constituent listed in the facility permit for specification in the permit upon approval by the Secretary;

K. Ensure that the sampling procedure required by §J of this regulation consists of either:

(1) A sequence of at least four samples taken by the owner or operator at an interval that assures, to the greatest extent technically feasible, that an independent sample is obtained, considering the:

(a) Uppermost aquifer's effective porosity;

(b) Hydraulic conductivity of the uppermost aquifer;

(c) Hydraulic gradient in the uppermost aquifer; and

(d) Fate and transport characteristics of the potential contaminants; or

(2) An alternate sampling procedure proposed by the owner or operator and approved by the Secretary.

L. Maintain, as part of the facility operating record, ground water monitoring data collected in accordance with §§J and K of this regulation, including actual levels of constituents;

M. Submit ground water monitoring data collected in accordance with Regulation .06B of this chapter to the Secretary for the Secretary's review on a schedule as specified in the facility CHS permit.