Pennsylvania Code › Title 25 - ENVIRONMENTAL PROTECTION › Part I - Department of Environmental Protection › Subpart C - Protection of Natural Resources › Article I - Land Resources › Chapter 78a - UNCONVENTIONAL WELLS › Subchapter C - ENVIRONMENTAL PROTECTION PERFORMANCE STANDARDS › Section 78a.59a - Impoundment embankments

Current through Register Vol. 54, No. 28, July 13, 2024
(a)
						Embankments constructed for well development impoundments for oil and gas
						operations must meet the following requirements:
(1) The foundation for each embankment shall
						be stripped and grubbed to a minimum depth of 2 feet below existing contour
						prior to any placement and compaction of fill.
(2) Any springs encountered in the embankment
						foundation area shall be drained to the downstream toe of the embankment with a
						drain section 2 feet by 2 feet in dimension consisting of PennDOT Type A sand,
						compacted by hand tamper. Geotextiles may not be used around sand. The last 3
						feet of this drain at the downstream slope must be constructed of AASHTO # 8
						material.
(3) The minimum top width
						of the embankment must be 12 feet.
(4) The inside and outside slope must have a
						slope no steeper than 3 horizontal to 1 vertical.
(5) Soils to be used for embankment
						construction must be classified in accordance with ASTM D-2487 (Unified Soils
						Classification). Soil samples must be classified at a minimum rate of one
						sample per 10,000 cubic yards of placed fill with at least one test per source
						with an additional test conducted each time the material changes. At least one
						sample must be classified in accordance with ASTM D-2487. Soils utilized during
						embankment construction shall be described and identified in accordance with
						ASTM D-2488-09A (Standard Practice for Description and Identification of Soils
						(Visual-Manual Procedure)). Soil identification and description in accordance
						with this procedure shall be performed at a minimum rate of one sample per
						1,000 cubic yards of placed fill. Results of testing of materials shall be
						provided to the Department upon request.
(6) The embankment must be constructed out of
						soils designated as GC, GM, SC, SM, CL or ML, only. Soils with split
						designations when one of the designations is not GC, GM, SC, SM, CL or ML may
						not be used. Soils must contain a minimum of 20% of No. 200 sieve materials or
						larger. Results of testing of materials shall be provided to the Department
						upon request.
(7) Particles greater
						than 6 inches in any dimension may not be used for embankment
						construction.
(8) Soil used in
						embankment construction must be compacted. Soil compaction shall be conducted
						in accordance with the following:
(i)
						Compaction shall be conducted with a sheepsfoot or pad roller.
(ii) The maximum loose lift thickness must be
						9 inches.
(iii) Soil shall be
						compacted until visible nonmovement of the embankment material.
(iv) Soil shall be compacted to a minimum of
						95% of the standard proctor in accordance with ASTM D698 (Standard Test Methods
						for Laboratory Compaction Characteristics of Soil Using Standard Effort).
						Satisfactory compaction shall be verified by field density testing in
						accordance with ASTM D1556 (Standard Test Method for Density and Unit Weight of
						Soil in Place by the Sand Cone Method) or ASTM D6938 (Standard Test Method for
						In-Place Density and Water Content of Soil and Soil-Aggregate by Nuclear
						Methods (Shallow Depth)) with a minimum of one test per 2,000 square yards of
						lift surface and at least one test per lift.
(9) Exposed embankment slopes shall be
						permanently stabilized using one or a combination of the following methods:
(i) Exposed embankments shall be limed,
						fertilized, seeded and mulched, and permanent vegetative ground covering in
						compliance with §
														102.22 (relating to site
						stabilization) shall be established upon completion of construction of the
						impoundment.
(ii) Compacted rock
						fill or riprap placed on the downstream face of the embankment as a cover
						having a minimum depth of 2 feet. The rock fill must be durable, evenly
						distributed and underlain by a Class 2, Type A
						geotextile.