Okla. Admin. Code § 252:515-9-5

Current through Vol. 42, No. 3, October 15, 2024

Section 252:515-9-5 - Monitoring well number and location

(a)Site-specific considerations. A thorough characterization of the following shall be submitted with the permit application to support the number, spacing, and depths of monitoring wells proposed:

(1) aquifer thickness, groundwater flow rate, groundwater flow direction including seasonal and temporal fluctuations in groundwater flow; and

(2) saturated and unsaturated geologic units and fill materials overlying the uppermost aquifer, materials comprising the uppermost aquifer, and materials comprising the confining unit defining the lower boundary of the uppermost aquifer; including, but not limited to: thicknesses, stratigraphy, lithology, hydraulic conductivities, porosities and effective porosities.

(b)Minimum number. The minimum number of groundwater monitoring wells to be installed shall be as follows.

(1)Land disposal facilities. Except as provided in (2) of this Subsection, all land disposal facilities shall be equipped with at least one monitoring well located hydraulically upgradient of the disposal facility, and three located hydraulically downgradient of the disposal facility.

(2)C&D landfills. C&D landfills shall be equipped with at least one monitoring well located hydraulically upgradient of the disposal facility, and two located hydraulically downgradient of the disposal facility.

(3)Additional wells. The installation of additional monitoring wells may be required to adequately monitor groundwater in areas of complex hydrogeology.

(c)Alternative upgradient. The use of wells that are not hydraulically upgradient of the waste management area may be approved when:

(1) hydrogeologic conditions do not allow the owner/operator to determine what wells are hydraulically upgradient; or

(2) sampling at other wells will provide an indication of background groundwater quality that is as representative or more representative than that provided by the upgradient wells.

Okla. Admin. Code § 252:515-9-5

Added at 20 Ok Reg 1151, eff 6-1-03