Okla. Admin. Code § 35:17-3-13

Current through Vol. 42, No. 4, November 1, 2024

Section 35:17-3-13 - Criteria for liners

(a) Soil liners shall be constructed to meet the following minimum requirements:

(1) Constructed in lifts or layers no more than six (6) inches thick when compacted.

(A) Soils used in the liner shall be free of foreign material, including trash, brush, and fallen trees.

(B) All side slopes and the floor of the retention structures shall be checked after each lift to ensure proper compaction and moisture content. All readings shall be recorded and properly documented. Minimum information required for documentation shall include:

(i) Project name.

(ii) Date.

(iii) Test method used per ASTM specification.

(iv) Site name.

(v) Technician name.

(vi) Location of reading, include sketch.

(vii) Percent compaction.

(viii) Wet density in pounds per cubic foot (pcf).

(ix) Dry density in pounds per cubic foot (pcf).

(x) Moisture content, percent.

(xi) Lift number.

(xii) Soils lab name, report number, and Proctor Test results used to obtain field measurements.

(2) Compaction to a minimum of ninety-five percent (95%) of Standard Proctor (ASTM D 698) at optimum or wetter moisture content.

(3) Hydraulic conductivities of no greater than 1x 10 ^-7 cm/sec. The field permeability of the liner shall be verified by using one of the following methods:

(A) If a sealed Double Ring Infiltrometer is used to determine the field permeability of the liner, at least one representative location on each corner and one location in the center of the waste retention structure bottom shall be selected for Double Ring Infiltrometer determination.

(B) At least four (4) representative undisturbed core samples, one from each corner of the waste retention structure bottom shall be retrieved for permeability determination in the laboratory. The permeability shall be determined using a Flexible Wall Permeameter (ASTM D 5084).

(4) Minimum thickness of one and one half (1.5) feet.

(5) Maximum hydrostatic head of ten and one half (10.5) feet.

(6) Hydrostatic head or water depth may be increased above ten and one half (10.5) feet in one of the following circumstances:

(A) Liner thickness above the minimum shall be increased by an amount needed to maintain the allowable seepage rate, which shall not exceed eighty three one hundredths (0.83) feet per year pursuant to Darcy's Velocity.

(B) Soils with permeabilities less than 1 x 10 ^-7 cm/sec are used to maintain the allowable seepage rate, which shall not exceed eighty three one hundredths (0.83) feet per year pursuant to Darcy's Velocity. Soils which do not meet the maximum criteria of 1 x 10 ^-7 cm/sec can be mixed with a sufficient amount of bentonite clay to achieve the desired standard.

(C) Any combination of (A) or (B). In no case shall hydraulic conductivity be used to reduce the minimum thickness of one and one half (1.5) feet or shall thickness be used to increase the maximum hydraulic conductivity of 1 x 10 ^-7 cm/sec.

(b) The owner shall maintain the liner to inhibit infiltration of wastewaters. Liners shall be protected from burrowing and other animals by fences or other protective devices. Liners shall also be protected from the potential root zone of all trees.

(c) Any mechanical or structural damage to the liner shall be evaluated by an environmental, agricultural, or other Department approved professional engineer registered in the state of Oklahoma within thirty (30) calendar days of the damage. Documentation of liner maintenance shall be kept with the Pollution Prevention Plan.

(d) Flexible membrane or synthetic liners may be used in connection with a soil liner or as a substitute for a soil liner. Geosynthetic liners and flexible membrane liners shall be installed so as to protect waters of the State from contamination.

(1) The subgrade soil shall be prepared according to the design standards. A subgrade verification form shall be submitted with liner documentation.

(2) The surface to be lined shall be rolled and compacted and free of irregularities, undulations, protrusions, vegetation, excessive moisture, loose soil, or abrupt changes in slope.

(3) The subgrade surface shall be free of foreign material including stones, cobbles, broken pieces of wood, plastic, or glass.

(4) The owner shall provide a copy of a completed Surface Acceptance Form indicating acceptable locations. In no case shall the installer deploy any geomembrane or flexible membrane liner in areas not acceptable within these rules.

(5) If at any time during the installation the subgrade surface deteriorates or is damaged, or in any way deemed unacceptable by the regulatory authority, all work shall stop until proper repair is performed.

(6) The anchor trench shall be constructed according to the standard industry practices. The trench shall be adequately drained to prevent ponding or softening of the side walls. After installation of the liner, the trench shall be back filled, compacted, and anchored according to the standards.

(7) The liner placement plan shall take into consideration the site drainage, low lying areas, temperature, and prevailing wind velocity and direction. Field panels shall be deployed one at a time and seamed as soon as possible to minimize the risk of wind or water damage.

(8) Field panel deployment shall not proceed at an ambient temperature below forty degrees (40°) F, unless Low Temperature Welding Procedures are used. All deployed panels should be amply ballasted or sand bagged at all times to avoid wind damage.

(9) Personnel responsible for placement of the liner shall not smoke, wear damaging shoes, or engage in other activities which may cause damage to the liner. The method of deployment shall not cause scratches, crimps, or tear the liner or damage the subgrade. Adequate sand bags shall be placed on the edges of the liner to avoid wind uplifting.

(10) The installer shall visually inspect the panels as soon as possible after deployment for damage or distressed surfaces.

(11) A seam is considered a separate entity if it joins two panels. Repairs are not considered seams in this context. Seams shall be generally oriented parallel to the line of maximum slope, or along instead of across the slope. In corners and odd shaped geometric locations the number of seams should be minimized.

(12) The Extrusion Process shall be used only for repairs and patching and shall not be used for the overall operation. The Fusion Process shall be used for seaming panels together using hot-wedge type or solid wedge type automated self-propelled apparatus equipped with temperature gauges.

(13) The nondestructive seam continuity test shall be performed during daylight hours and certified by the owner.

Okla. Admin. Code § 35:17-3-13

Added at 15 Ok Reg 102, eff 10-13-97 (emergency); Added at 15 Ok Reg 2508, eff 6-25-98; Amended at 15 Ok Reg 4247, eff 9-2-98 (emergency); Amended at 16 Ok Reg 1717, eff 6-1-99; Amended at 29 Ok Reg 903, eff 7-1-12

Amended by Oklahoma Register, Volume 37, Issue 24, September 1, 2020, eff. 9/14/2020