Guidelines for the Design, Construction, Operation, and ...

1 Commonwealth of Massachusetts Department of Environmental Protection Division of Watershed Permitting Revised July 2018 Guidelines for the design , Construction, Operation, and Maintenance of Small wastewater Treatment Facilities with Land Disposal Final Revised July 2018 2 TABLE OF CONTENTS PAGE LIST OF TABLES & FIGURES 3 INTRODUCTION 4 ACKNOWLEDGEMENTS 6 I LAWS AND REGULATIONS A. STATE 7 B. LOCAL 9 C. FEDERAL 10 D. LIST OF ACRONYMS 11 II FILING FOR A GROUNDWATER PERMIT 15 III REQUIRED SUBMITTALS A.

2 HYDROGEOLOGIC STUDY 20 B. ENGINEERING REPORT 22 C. PLANS & SPECIFICATIONS 24 D. O&M PLAN 25 E. DOCUMENTATION OF OWNERSHIP AND FINANCES 26 F. CONTRACT SERVICES 30 IV wastewater FLOWS A. CALCULATION OF FLOWS 32 B. DETERMINATION OF UNUSED CAPACITY 37 V INFILTRATION/INFLOW & SEWER SYSTEM MAINTENANCE 39 VI SITE EVALUATION & SITING CRITERIA 40 VII EFFLUENT DISPOSAL 44 VIII GENERAL REQUIREMENTS FOR TREATMENT PLANTS REQUIREMENTS 54 WWTF REQUIREMENTS 57 C. CONSTRUCTION OVERSIGHT 63 IX design CRITERIA A. COLLECTION SYSTEM 64 B. PUMPING STATIONS 71 C. FLOW EQUALIZATION 73 D. PRELIMINARY AND PRIMARY TREATMENT 75 E.

3 SECONDARY TREATMENT 78 F. SECONDARY CLARIFICATION 88 G. NITROGEN & PHOSPHORUS REMOVAL 90 H. FILTRATION 97 I. OTHER ADVANCED TREATMENT PROCESSES 99 J. DISINFECTION 102 K. RESIDUALS MANAGEMENT/FOG REQUIREMENTS/ GREASE TRAPS 106 L. INSTRUMENTATION 109 TECHNOLOGIES 114 N. SCHOOLS & OTHER SEASONAL FACILITIES 115 X OPERATION & MAINTENANCE PLAN 117 XI GROUNDWATER PERMIT REQUIREMENTS 126 XII CERTIFICATION & PERFORMANCE GUARANTEES 129 Final Revised July 2018 3 LIST OF TABLES TABLE TITLE PAGE 1 REGULATION SUMMARY 12 2 MINIMUM ACCEPTABLE SEPARATION DISTANCES 43 3 design LOADING RATE GALLONS PER DAY PER SQUARE FOOT (GPD/SF)

4 47 4 SUMMARY OF PRIMARY CLARIFIER design CONSIDERATIONS 78 5 SUMMARY OF ROTATING BIOLOGICAL CONTACTOR CONSIDERATIONS 82 6 AERATION TANK CAPACITIES AND PERMISSIBLE LOADINGS 83 7 SECONDARY CLARIFIER design CONSIDERATIONS 90 LIST OF FIGURES FIGURE TITLE PAGE 1 MERRIMACK CURVE 36 2 TYPICAL UTILITY PIPE SEPARATIONS 67 APPENDIX A CERTIFICATION STATEMENT 131 B INFILTRATION RATE AND INFILTRATION RATE TEST 132 C DIVISION OF WATER SUPPLY POLICY BRP/DWM/WS/P03-1: 139 REVIEW OF SEWER LINE/WATER SUPPLY PROTECTION D SUGGESTED MAINTENANCE REQUIREMENTS 143 Final Revised July 2018 4 INTRODUCTION The field of environmental engineering and regulatory framework has advanced significantly since MassDEP developed the Guidelines for the design , Construction, Operation and Maintenance of Small Sewage Treatment Facilities with Land Disposal Second Draft: January 1988 and the subsequent revisions in April 2004.

5 The 2012 document includes a substantial updating to reflect improvements in wastewater treatment technology and new regulatory changes which establish proper design , construction and operational practices for small wastewater treatment works with discharge to groundwater. Our understanding of groundwater flow dynamics and the potential for impacts on downstream resources has grown. There are also a number of new MassDEP policies and initiatives which directly impact the groundwater program. Lastly, our experience in reviewing the design and operation of wastewater treatment facilities over the years has given us a keen insight into what is necessary to construct, operate, and maintain a modern facility.

6 This document is intended to serve as a technical guide for individuals involved in the design , construction, and use of small wastewater treatment facilities in the Commonwealth of Massachusetts. It outlines the current regulations, policies, and standards of MassDEP as they relate to facilities that discharge to the ground. For the purposes of this document, small treatment facilities are defined as those with a sewage flow of between 10,000 and 150,000 gallons per day (gpd). This document only applies to these small treatment facilities. It is the MassDEP s intent that this guidance be used as a supplement to the standards and design criteria found in the document published by the New England Interstate Water Pollution Control Commission titled TR-16: Guides for the design of wastewater Treatment Works 2011 Edition.

7 TR-16 is and will continue to remain as the primary design reference for MassDEP use. This additional guidance is not intended to replace TR-16, but rather to provide further information and standards, where necessary, given the particular problems that we face in Massachusetts in the design and construction of land-based systems. It should be emphasized that while this guidance is intended primarily for small systems, many of the principles and design criteria are also applicable to larger systems. The larger systems (> 150,000 gpd) present a different set of issues that have to be evaluated in a separate manner. As an example, such topics include flow derivation, size of effluent disposal reserve area and/or redundancy, and level of hydrogeologic evaluation.

8 Whenever possible, differences in approach will be noted in the text. In addition to TR-16, other documents used in the development of this guidance and to be read in conjunction with include: wastewater Engineering: Treatment, Disposal, and Reuse 3rd Edition Metcalf & Eddy Final Revised July 2018 5 Water Reuse: issues, Technologies, and Applications Metcalf & Eddy/AECOM Biological wastewater Treatment 2nd Edition Grady, Daigger, & Lim wastewater Treatment Plant design : Manual of Practice (MOP 8) Water Environment Federation Process design Manual.

9 Land Treatment of municipal wastewater United States Environmental Protection Agency (EPA 625/1-81-013) Process design Manual: Land Treatment of municipal wastewater Supplement on Rapid Infiltration and Overland Flow United States Environmental Protection Agency (EPA 625/1-81-013a) The Northeast Guide for Estimating Staffing at Publicly and Privately Owned wastewater Treatment Plants New England Interstate Water Pollution Control Commission (November 2008) Final Revised July 2018 6 ACKNOWLEDGEMENT This document represents the collective thought and expertise of many individuals both within and outside MassDEP of Environmental Protection.

10 Without the active involvement of these individuals and the organizations and agencies they represent, this publication would not be possible. Specifically, MassDEP would like to thank the following individuals and organizations for their time in reviewing and commenting on these documents: Mark Beaudry Meridian Associates Charles Button STANTECH Michael Giggey Wright-Pierce Engineers Thomas Parece AECOM George Preble Beals & Thomas, Inc. David Young CDM Smith Department of Environmental Protection Staff Kevin Brander June Mahala David Boyer Paul Nietupski Marybeth Chubb John Ostrosky Andrew Cohen Brett Rowe Lisa Dallaire Alan Slater Deirdre Desmond Harold Stephens Brian Dudley Greg Tomaszewski David Ferris Margaret Webber Claire Golden Ronald White Stephen Hallem Dana Hill Robert Kimball Alan Slater of the Massachusetts Department of Environmental Protection was the technical editor and project manager for this effort.