Wyoming Administrative Code
Agency 020 - Environmental Quality, Dept. of
Sub-Agency 0011 - Water Quality
Chapter 28 - STANDARDS FOR ISSUING PERMITS FOR COMMERCIAL OILFIELD WASTE DISPOSAL FACILITIES
Section 28-10 - Minimum Design and Construction Standards

Universal Citation: WY Code of Rules 28-10

Current through September 21, 2024

(a) Receiving facility and phase separation facility designs shall meet the following standards:

(i) Liquid hydrocarbons shall be removed from wastewater before it is discharged to the evaporation ponds.

(ii) All open-topped tanks in the receiving facility and the phase separation facility shall be covered with netting, screen, or other approved method to prevent the entry of birds and other wildlife. The netting, screen, or approved covering shall be constructed to remain intact and above the surface of the liquid in the tank even during winds up to eighty (80) mph, or when weighted with snow, ice, or rain.

(b) To protect birds and other wildlife, evaporation ponds shall be kept virtually oil free at all times or shall be completely netted or screened to the standards required for open-topped tanks. Hydrocarbon sheen on any part of the evaporation ponds shall be removed immediately.

(c) The facility design shall meet the following earthwork standards:

(i) For evaporation ponds specified to be lined with a geomembrane liner:
(A) Rocks larger than six (6) inches in length shall not be placed within five (5) feet of the interior slope of any evaporation pond embankment. All rocks and other material that could damage the geomembrane shall be removed from the surface to be covered with the geomembrane;

(B) Material containing by volume less than twenty-five (25%) percent of rock larger than six (6) inches and less than twelve (12) inches in length may be placed in the remainder of the embankment.

(ii) Outer dike slopes shall not be steeper than a ratio of one (1) vertical to three (3) horizontal in order to prevent surface runoff from entering the evaporation ponds. The Administrator may require flatter slopes to maintain slope stability.

(iii) Inner dike slopes shall be between a ratio of one (1) vertical to four (4) horizontal and one (1) vertical to three (3) horizontal.

(iv) The minimum top dike width shall be twelve (12) feet to allow access to maintenance vehicles. Top dikes wider than twelve (12) feet shall be required when necessary to ensure structural stability.

(v) Freeboard design shall comply with the following requirements:
(A) The minimum freeboard at the maximum operating level shall be three (3) feet.

(B) In order to prevent unauthorized discharges to the air, land or Waters of the State, the Administrator may require increased freeboard, on a case-by-case basis, in order to compensate for wave action due to evaporation pond design, meteorological, or topographic conditions that may exceed the proposed freeboard.

(d) The facility design shall meet the following liner base, primary and secondary liner, and leak detection system standards:

(i) All evaporation ponds shall be constructed with a compacted clay secondary liner base or a geosynthetic clay secondary liner base that is contoured to include individual sub-cells that can be isolated if a leak is detected, as required in Section 10(d)(iv)(C)(I).
(A) Compacted clay secondary liner bases shall be a minimum of one (1) foot thick with a maximum permeability of 1 X 10-5 cm/sec and shall be constructed with maximum compacted lifts of one-half (1/2) foot.
(I) Tests for water content and density shall be taken during the placement of each lift of the liner base.
1. Either permeability testing of undisturbed core samples from the in-place seal or detailed tests such as particle size distribution and Atterberg limits shall be conducted.

2. Detailed tests shall confirm that the soil specified was used for liner construction. One (1) test shall be conducted per acre per lift. For core sampling of the in-place liner, one (1) core of the completed liner shall be tested per acre.

3. The permittee shall provide the Division a written certification by a Wyoming Professional Engineer that the base was constructed according to the permit and that final testing indicated results within the allowable limits established by the permit.

(II) For compacted clay secondary liner bases, a method of maintaining the seal at or above optimum moisture conditions is required.

(B) Geosynthetic clay secondary liner bases installed according to the manufacturer's instructions are acceptable, provided that:
(I) Geosynthetic clay liner bases shall have a maximum hydraulic conductivity of 1 X 10-8 cm/sec;

(II) The manufacturer of the geosynthetic clay liner base shall have more than ten million square feet of their product installed;

(III) The geosynthetic clay liner base installation contractor shall be approved by the manufacturer; and

(IV) Geosynthetic clay liners that are used as secondary liner bases require surface erosion and abrasion protection and shall be protected during installation consistent with the manufacturer's requirements. If interior pond slopes steeper than 3:1 horizontal to vertical are proposed, the factor of safety for slope failure on the composite liner shall be shown to be at least 1.5:1.

(C) Handling, installation, and testing of geosynthetic clay liners shall be in accordance with the following specifications:
(I) ASTM D5887/D5887M-16;

(II) ASTM D5888-19;

(III) ASTM D5889/D5889M-18;

(IV) ASTM D5890-19;

(V) ASTM D5891/D5891M-19;

(VI) ASTM D5993-18;

(VII) ASTM D6072/D6072M-19;

(VIII) ASTM D6102-15;

(IX) ASTM D6243/D6243M-16;

(X) ASTM D6788-02(2017);

(XI) ASTM D6495/D6495M-18;

(XII) ASTM D6768/D6768M-19;

(XIII) ASTM D6496/D6496M-19;

(XIV) ASTM D6243; and

(XV) GRI GCL3.

(ii) All evaporation ponds shall be constructed with a high-density polyethylene (HDPE) geomembrane secondary liner that shall have a minimum thickness of 40 mils.
(A) HDPE geomembrane liners that conform to Geosynthetic Research Institute Standard Specification GRI-GM13, are acceptable.

(B) Handling, installation, and testing of HDPE liners shall be in accordance with the following specifications:
(I) GRI GM13;

(II) GRI GM9;

(III) ASTM D751-19;

(IV) ASTM D792-13;

(V) ASTM D814-95(2020);

(VI) ASTM D882-18;

(VII) ASTM D1004-13;

(VIII) ASTM D1203-16;

(IX) ASTM D1204-14;

(X) ASTM D1505-18;

(XI) ASTM D1593-19;

(XII) ASTM D1603-14;

(XIII) ASTM D1790-14;

(XIV) ASTM D3895-19;

(XV) ASTM D4218-15;

(XVI) ASTM D4833/D4833M-07(2013);

(XVII) ASTM D5199-12(2019);

(XVIII) ASTM D5321/D5321M-20;

(XIX) ASTM D5397-19a;

(XX) ASTM D5596-03(2016);

(XXI) ASTM D5721-08(2018);

(XXII) ASTM D5885/D5885M-17;

(XXIII) ASTM D5994/D5994M-10(2015)e1;

(XXIV) ASTM D6392-12(2018);

(XXV) ASTM D6497/D6497M-02(2015)e1;

(XXVI) ASTM D6693/D6693M-04(2015)e1;

(XXVII) ASTM D7466/D7466M-10(2015)e1; and

(XXVIII) ASTM D7238-06(2017)07/01/2017.

(C) The liner manufacturer shall have more than ten million square feet of their product installed.

(D) Geomembrane liners installed and operated according to this Section shall not allow a discharge to groundwater by direct or indirect discharge, percolation or infiltration.

(iii) All evaporation ponds shall be constructed with a leak detection system that when installed, shall allow monitoring as required in Section 11(b) of this Chapter.

(iv) The leak detection system shall include drainage layers between the primary and secondary liners that shall have a minimum hydraulic transmissivity of one (1) gpm/foot.
(A) Synthetic drainage media may be used.

(B) The drainage layer shall have a minimum grade of four-tenths of one percent (0.4 %).

(C) Perforated or slotted collection lines shall be installed in the drainage layer arranged to create sub-cells with a maximum area of two (2) acres or less.
(I) Collection lines shall be configured to isolate sub-cells in the collection system for the purpose of locating leaks.

(II) No portion of the drainage layer shall be more than 140 feet from a collection line.

(D) The collection lines shall drain to a sump contained by the secondary liner.
(I) The sump shall be designed so that the maximum high liquid level during operating conditions is below the invert of any collection line discharging to the sump.

(II) The sump shall be large enough to allow a pump to be installed to remove all fluid from the sump.

(v) All evaporation ponds shall be constructed with a primary liner that shall be an HDPE geomembrane liner with a minimum thickness of sixty (60) mils.
(A) HDPE geomembrane liners shall conform to Geosynthetic Research Institute Standard Specification GRI-GM13;

(B) Handling, installation, and testing of HDPE liners shall meet the requirements of paragraph (d)(ii)(B) of this Section;

(C) The liner manufacturer shall have more than ten million square feet of their product installed;

(D) Geomembrane liners installed and operated according to this subparagraph shall not allow a discharge to groundwater by direct or indirect discharge, percolation, or filtration.

Disclaimer: These regulations may not be the most recent version. Wyoming may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.