DESIGN STANDARDS FOR PUBLIC SEWAGE SYSTEMS

1 CIRCULAR DEQ-2 DESIGN STANDARDS FOR PUBLIC SEWAGE SYSTEMS 2018 2016 Edition CIRCULAR DEQ-2 (formerly Circular WQB-2) Adopted 03/24/95 Initially Effective 04/28/95 Revised 8/30/99 Revised 10/12/12 Revised 6/03/16 Revised 12/21/18 Montana Department of Environmental Quality (Established 07/01/95; formerly Montana Department of Health and Environmental Sciences) I TABLE OF CONTENTS I CHAPTER 10 ENGINEERING REPORTS AND FACILITY PLANS .. 3 10. GENERAL .. 3 11. ENGINEERING REPORT OR FACILITY PLAN .. 3 CHAPTER 20 ENGINEERING PLANS AND SPECIFICATIONS .. 13 20. PLANS AND SUPPORT DOCUMENTS.

2 13 21. SPECIFICATIONS .. 16 22. REVISIONS TO APPROVED PLANS .. 16 23. ADDITIONAL INFORMATION REQUIRED .. 17 24. DEVIATIONS FROM STANDARDS .. 17 25. OPERATION & MAINTENANCE MANUAL .. 17 CHAPTER 30 DESIGN OF SEWERS .. 19 31. SEPARATION OF CLEAR WATER .. 19 32. DESIGN CAPACITY AND DESIGN FLOW .. 19 33. DETAILS OF DESIGN AND CONSTRUCTION .. 19 34. MANHOLES .. 25 35. INVERTED SIPHONS .. 27 36. SEWERS IN RELATION TO STREAMS .. 27 37. AERIAL CROSSINGS .. 28 38. PROTECTION OF WATER SUPPLIES .. 28 39. SEWER SERVICES AND PLUMBING .. 30 CHAPTER 40 wastewater PUMPING STATIONS .. 31 41. GENERAL .. 31 42. DESIGN .. 31 43. SUCTION LIFT PUMP STATIONS.

3 36 44. SUBMERSIBLE PUMP STATIONS - SPECIAL CONSIDERATIONS .. 37 45. SCREW PUMP STATIONS SPECIAL CONSIDERATIONS .. 37 46. ALARM SYSTEMS .. 38 47. EMERGENCY OPERATION .. 38 48. INSTRUCTIONS AND EQUIPMENT .. 41 49. FORCE MAINS .. 41 CHAPTER 50 wastewater TREATMENT FACILITIES .. 43 51. PLANT LOCATION .. 43 52. QUALITY OF EFFLUENT .. 43 53. DESIGN .. 43 54. PLANT DETAILS .. 45 55. PLANT OUTFALLS .. 47 56. ESSENTIAL FACILITIES .. 47 57. SAFETY .. 50 58. LABORATORY .. 53 CHAPTER 60 SCREENING, GRIT REMOVAL, AND FLOW 61 61. SCREENING DEVICES .. 61 I 62. COMMINUTORS AND GRINDERS .. 64 63. GRIT REMOVAL FACILITIES .. 65 64.

4 PRE-AERATION .. 67 65. FLOW EQUALIZATION .. 67 CHAPTER 70 SETTLING .. 69 71. GENERAL .. 69 72. DESIGN CONSIDERATIONS .. 69 73. SLUDGE AND SCUM 72 74. PROTECTIVE AND SERVICE 73 CHAPTER 80 SLUDGE PROCESSING, STORAGE, AND DISPOSAL .. 75 81. GENERAL .. 75 82. PROCESS SELECTION .. 75 83. SLUDGE THICKENERS .. 75 84. ANAEROBIC SLUDGE DIGESTION .. 76 85. AEROBIC SLUDGE DIGESTION .. 82 86. HIGH PH STABILIZATION .. 85 87. SLUDGE PUMPS AND PIPING .. 87 88. SLUDGE DEWATERING .. 88 89. SLUDGE STORAGE AND DISPOSAL .. 90 CHAPTER 90 BIOLOGICAL TREATMENT .. 95 91. TRICKLING 95 92. ACTIVATED 98 93. wastewater TREATMENT PONDS.

5 105 94 ROTATING BIOLOGICAL CONTACTORS .. 114 95. BIOLOGICAL NUTRIENT REMOVAL (BNR) .. 115 96. SEQUENCING BATCH REACTOR (SBR) .. 121 97. MEMBRANE BIOREACTOR (MBR) .. 127 98. OTHER BIOLOGICAL SYSTEMS .. 131 CHAPTER 100 DISINFECTION .. 133 101. GENERAL .. 133 102. CHLORINE DISINFECTION .. 133 103. DECHLORINATION .. 137 104. ULTRAVIOLET RADIATION DISINFECTION .. 139 105. OZONE .. 141 CHAPTER 110 SUPPLEMENTAL TREATMENT PROCESSES .. 143 111. CLARIFICATION PROCESSES .. 143 112. HIGH RATE EFFLUENT FILTRATION .. 149 CHAPTER 120 IRRIGATION AND RAPID INFILTRATION SYSTEMS .. 153 3 121. STANDARDS FOR THE USE OF RECLAIMED wastewater FOR.

6 153 122. STANDARDS FOR RAPID INFILTRATION 172 APPENDIX A HANDLING & TREATMENT OF SEPTAGE AT A wastewater TREATMENT PLANT ..A-1 NEW APPENDIX B WATER RECLAMATION & REUSE .. B-1 APPENDIX C ALTERNATIVE SEWER COLLECTION NEW APPENDIX D GUIDELINES FOR SEWER REHABILITATION ..D-1 NEW APPENDIX E CAPACITY DEVELOPMENT FOR PUBLIC SEWAGE E-1 4 I FOREWORD The Board of Environmental Review of the State of Montana, as authorized by 75-6-103(2)(f), MCA, has adopted the following STANDARDS for wastewater works. The terms "Department", as used in these STANDARDS refer to the Montana Department of Environmental Quality (DEQ) or its authorized agents.

7 These STANDARDS are intended to establish planning and DESIGN criteria for PUBLIC SEWAGE SYSTEMS as defined in 17-6-102(13) MCA insofar as the criteria are applicable to normal situations for an individual project. The DESIGN criteria in these STANDARDS are intended for the more conventional municipal wastewater collection and treatment SYSTEMS where any industrial component of the wastewater is relatively small. When a significant industrial component exists or is planned within a collection system, an effective pretreatment program must be enacted to ensure toxic substances will not disrupt the biological treatment process.

8 Lack of description or criteria for a unit process does not suggest it should not be used, only that consideration by the Department will be on the basis of information submitted with the DESIGN . Engineering data that may be required by the Department, for new process and application evaluation is included in Section (Engineering and Performance Requirements for Innovative wastewater Treatment Alternatives). These STANDARDS are intended to define limiting values for items upon which an evaluation of such plans and specifications will be made by the Department; and to establish, as far as practicable, uniformity of practice.

9 Users should also be cognizant of applicable federal requirements. Where monitoring or sampling procedures are required within this document, the procedures and methods used to analyze each sample must follow the Standard Methods for the Examination of Water & wastewater , 21st edition or its updates. Deviations from the criteria are allowed on a case-by-case basis. The DESIGN engineer must submit a request, with appropriate technical justification, for a deviation from a specific section of the STANDARDS indicating how the criteria will be changed. The terms "shall", "must" and "required" are used where practice is sufficiently standardized to permit specific delineation of requirements or where safeguarding of the PUBLIC health or protection of water quality justifies such definite action.

10 Other terms , such as "should," "may," "recommended," and "preferred," indicate desirable procedures or methods. Definition of terms and their use in these STANDARDS is intended to be in accordance with GLOSSARY- WATER AND wastewater CONTROL ENGINEERING, jointly prepared by APHA, ASCE, AWWA and WEF (formerly WPCF). The units of expression used are in accordance with those recommended in WEF (formerly WPCF) MANUAL OF PRACTICE NUMBER 6, UNITS OF EXPRESSION FOR wastewater TREATMENT. These STANDARDS are based on Circular DEQ-2, Montana Department of Environmental Quality, DESIGN STANDARDS for wastewater Facilities, 1999 Edition, that were based on "The Recommended STANDARDS for wastewater Facilities", 1997 Edition, prepared by the Great Lakes - Upper Mississippi River Board of State and Provincial PUBLIC Health and Environmental Managers.