NR 110.24(3)(e)(e) Lagoon shape. The shape of lagoons shall be such that there are no narrow or elongated portions. Islands, peninsulas or coves will not be approved. Dikes shall be rounded at corners to minimize accumulations of floating materials. Commonwall dike construction is encouraged. Round, square or rectangular lagoons with a length not exceeding 3 times the width are recommended. NR 110.24(3)(f)4.4. A minimum one meter (3 feet) freeboard from operating water surface to the top of dikes shall be provided. NR 110.24(3)(g)1.1. A minimum liquid depth of 0.6 meters (2 feet) for stabilization ponds and 1.8 meters (6 feet) for aerated lagoons shall be provided. NR 110.24(3)(g)2.2. Maximum water depth may not exceed 1.8 meters (6 feet) for stabilization ponds and 4.3 meters (15 feet) for aerated lagoons. NR 110.24(4)(a)(a) General. All lagoons shall be sealed to prevent excessive exfiltration. NR 110.24(4)(b)1.1. Loss of water from wastewater treatment or storage lagoons may not exceed 10 cubic meters per water surface hectare (1,000 gallons per acre) per day and loss of water from sludge storage or treatment lagoons or other sludge handling facilities may not exceed 5 cubic meters per sludge surface hectare (500 gallons per acre) per day. NR 110.24(4)(b)2.2. In circumstances where soil or groundwater characteristics, groundwater quality, or waste characteristics warrant, the department may require exfiltration rates less than 10 cubic meters per water surface hectare (1,000 gallons per acre) per day for wastewater treatment or storage lagoons. NR 110.24(4)(c)1.1. Soil materials or synthetic liners approved by the department may be used to seal lagoons. NR 110.24(4)(c)2.2. Soil materials or synthetic liners used to seal lagoons shall be compatible with the wastewater characteristics. NR 110.24(4)(d)1.1. Core samples taken to determine soil texture, grain size distribution or permeability shall be taken in accordance with ASTM D1586-08a, ASTM D1587-08, or ASTM 3550-01 (2007). NR 110.24(4)(d)2.2. Permeability shall be determined using a falling head permeability test. The test shall be performed at the same approximate density as the in-place field condition. Tests on remolded or undisturbed samples are acceptable. NR 110.24(4)(d)3.3. Sieve analyses performed to determine grain size distribution shall be performed in accordance with ASTM D422-63 (2007). NR 110.24(4)(d)4.4. Plasticity index shall be determined in accordance with ASTM D4318-10. NR 110.24(4)(d)5.5. Standard procter densities shall be determined in accordance with ASTM D698-07 e1. NR 110.24(4)(e)(e) Uniform construction. All lagoon seals shall be uniformly constructed across the lagoon bottom and interior dike walls. Seals shall extend up the dike wall to the berm. NR 110.24(4)(f)1.1. Synthetic liners shall have a minimum thickness of 0.8 millimeters (30 mils). NR 110.24(4)(f)2.2. All synthetic liners shall be installed under the supervision of a qualified manufacturer’s representative. NR 110.24(4)(f)3.3. Synthetic liners shall be protected by an inorganic soil layer. The soil layer shall have a minimum thickness of 30 centimeters (one foot). The soil shall be uniformly graded and free from large rocks, angular stones, soil clumps, sticks or other material which may puncture the liner. When a granular, noncohesive soil is used for the cover, a soil fabric shall be placed between the liner and the soil cover. The soil fabric shall be anchored at the dike berm.