WATER ENGINEERING Crites Second Edition Middlebrooks “The first edition of Natural Wastewater Treatment Systems has long served as the basis for understanding the design and performance of natural systems in treating Bastian wastewater. This updated edition will only enhance its recognition as an industry Reed standard.” —Michael Hines, M.S., P.E., Founding Principal, Southeast Environmental Engineering, LLC Calling for ecologically and economically sound wastewater treatment systems, the authors of Natural Wastewater Treatment Systems explore the use of wetlands, sprinkler irrigation, groundwater recharge, and other natural systems as sustainable N methods for the treatment and management of wastewater. Based on work by T prominent experts in natural waste treatment, this text provides a thorough explanation r a on how soil and plants can successfully sustain microbial populations in the e treatment of wastewater. Determining that natural systems cost less to construct and t operate and require less energy than mechanical treatment alternatives, the text also a u explains how these processes produce lower amounts of residual solids and use little or no chemicals. t r m a What’s New in the Second Edition: l This revised edition includes current design and regulatory and operational e developments in the natural wastewater treatment field. It provides detailed examples W Natural n and analyses along with significant operational data in each chapter. It also considers how processes provide passive treatment with a minimum of mechanical elements t a and describes new approaches to partially mixed ponds, including dual-powered aeration ponds. S s • Introduces the planning procedures and treatment mechanisms y t Wastewater e responsible for treatment in ponds, wetlands, land applications, and soil s absorption systems w t • Presents design criteria and methods of pond treatment and e a pond effluent upgrading m • Describes constructed wetlands design procedures, process applications, t Treatment treatment performance data, and land treatment concepts and design e s equations r • Provides new case studies of decentralized natural treatment and reuse systems • Includes examples of onsite wastewater management district operations Systems Designed for practicing wastewater engineers and scientists involved in the planning, Second design, and operation of ponds, wetlands, land treatment, biosolids, and onsite soil- Edition based treatment systems, the book integrates many natural treatment systems into one single source. Ronald W. Crites K18980 E. Joe Middlebrooks Robert K. Bastian 6000 Broken Sound Parkway, NW Suite 300, Boca Raton, FL 33487 711 Third Avenue an informa business New York, NY 10017 Sherwood C. Reed 2 Park Square, Milton Park www.crcpress.com Abingdon, Oxon OX14 4RN, UK www.crcpress.com Second Edition Natural Wastewater Treatment Systems Second Edition Natural Wastewater Treatment Systems Ronald W. Crites E. Joe Middlebrooks Robert K. Bastian Sherwood C. Reed Boca Raton London New York CRC Press is an imprint of the Taylor & Francis Group, an informa business CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2014 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Version Date: 20140114 International Standard Book Number-13: 978-1-4665-8327-6 (eBook - PDF) This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information stor- age or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copy- right.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that pro- vides licenses and registration for a variety of users. For organizations that have been granted a pho- tocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com Dedication We dedicate this book to the memory of Sherwood C. “Woody” Reed. Woody was the inspiration for this book and spent his wastewater engineering career planning, designing, evaluating, reviewing, teaching, and advancing the technology and understanding of natural wastewater treatment systems. Woody was the senior author of Natural Systems for Waste Management and Treatment, published in 1988, which introduced a rational basis for design of free water surface and subsurface flow constructed wetlands, reed beds for sludge treatment, and freezing for sludge dewatering. Woody passed away in 2003. © 2010 Taylor & Francis Group, LLC Contents Preface.....................................................................................................................xxi Authors .................................................................................................................xxiii Chapter 1 Natural Wastewater Treatment Systems: An Overview .......................1 1.1 Natural Treatment Processes .....................................................1 1.1.1 Background ..................................................................1 1.1.2 Wastewater Treatment Concepts and Performance Expectations............................................2 1.1.2.1 Aquatic Treatment Units ...............................2 1.1.2.2 Wetland Treatment Units ..............................2 1.1.2.3 Terrestrial Treatment Methods .....................5 1.1.2.4 Sludge Management Concepts ......................5 1.1.2.5 Costs and Energy ..........................................7 1.2 Project Development ..................................................................8 References ............................................................................................9 Chapter 2 Planning, Feasibility Assessment, and Site Selection ........................11 2.1 Concept Evaluation ..................................................................11 2.1.1 Information Needs and Sources .................................13 2.1.2 Land Area Required ...................................................13 2.1.2.1 Treatment Ponds .........................................13 2.1.2.2 Free Water Surface Constructed Wetlands ................................................15 2.1.2.3 Subsurface Flow Constructed Wetlands .....16 2.1.2.4 Vertical Flow Wetlands ..............................16 2.1.2.5 Overland Flow Systems ..............................16 2.1.2.6 Slow-Rate Systems......................................17 2.1.2.7 Soil Aquifer Treatment Systems .................18 2.1.2.8 Land Area Comparison ..............................18 2.1.2.9 Biosolids Systems .......................................18 2.2 Site Identification .....................................................................19 2.2.1 Site Screening Procedure ...........................................20 2.2.2 Climate .......................................................................25 2.2.3 Flood Hazard ..............................................................26 2.2.4 Water Rights ...............................................................26 2.3 Site Evaluation .........................................................................26 2.3.1 Soils Investigation ......................................................27 2.3.1.1 Soil Texture and Structure ..........................29 2.3.1.2 Soil Chemistry ............................................29 vii © 2010 Taylor & Francis Group, LLC viii Contents 2.3.2 Infiltration and Permeability ......................................31 2.3.2.1 Saturated Permeability ...............................31 2.3.2.2 Infiltration Capacity ....................................33 2.3.2.3 Porosity .......................................................33 2.3.2.4 Specific Yield and Specific Retention ........34 2.3.2.5 Field Tests for Infiltration Rate ...................35 2.3.3 Subsurface Permeability and Groundwater Flow ......37 2.3.3.1 Buffer Zones ...............................................38 2.4 Site and Process Selection .......................................................38 References ..........................................................................................39 Chapter 3 Basic Process Responses and Interactions .........................................41 3.1 Water Management ..................................................................41 3.1.1 Fundamental Relationships ........................................41 3.1.1.1 Permeability ................................................41 3.1.1.2 Groundwater Flow Velocity ........................42 3.1.1.3 Aquifer Transmissivity ...............................43 3.1.1.4 Dispersion ...................................................43 3.1.1.5 Retardation..................................................44 3.1.2 Movement of Pollutants ..............................................45 3.1.3 Groundwater Mounding .............................................48 3.1.4 Underdrainage ............................................................55 3.2 Biodegradable Organics ..........................................................57 3.2.1 Removal of BOD ........................................................57 3.2.2 Removal of Suspended Solids ....................................58 3.3 Organic Priority Pollutants and CECs ....................................59 3.3.1 Removal Methods .......................................................59 3.3.1.1 Volatilization...............................................59 3.3.1.2 Adsorption ..................................................61 3.3.2 Removal Performance ................................................65 3.3.3 Travel Time in Soils ...................................................66 3.4 Pathogens .................................................................................67 3.4.1 Aquatic Systems .........................................................67 3.4.1.1 Bacteria and Virus Removal .......................67 3.4.2 Wetland Systems ........................................................69 3.4.3 Land Treatment Systems ............................................70 3.4.3.1 Ground Surface Aspects .............................70 3.4.3.2 Groundwater Contamination ......................71 3.4.4 Sludge Systems ...........................................................71 3.4.5 Aerosols ......................................................................72 3.5 Metals ......................................................................................76 3.5.1 Aquatic Systems .........................................................77 3.5.2 Wetland Systems ........................................................78 3.5.3 Land Treatment Systems ............................................78 © 2010 Taylor & Francis Group, LLC Contents ix 3.6 Nutrients ..................................................................................80 3.6.1 Nitrogen ......................................................................80 3.6.1.1 Pond Systems ..............................................80 3.6.1.2 Aquatic Systems .........................................81 3.6.1.3 Wetland Systems .........................................81 3.6.1.4 Land Treatment Systems ............................81 3.6.2 Phosphorus .................................................................82 3.6.3 Potassium and Other Micronutrients ..........................83 3.6.3.1 Boron ..........................................................84 3.6.3.2 Sulfur ..........................................................84 3.6.3.3 Sodium ........................................................84 References ..........................................................................................85 Chapter 4 Design of Wastewater Pond Systems .................................................89 4.1 Introduction .............................................................................89 4.2 Facultative Ponds .....................................................................91 4.2.1 Areal Loading Rate Method ......................................91 4.2.2 Gloyna Method ...........................................................93 4.2.3 Complete-Mix Model .................................................95 4.2.4 Plug-Flow Model ........................................................96 4.2.5 Wehner–Wilhelm Equation ........................................97 4.2.6 ASM3 Extended Version ..........................................101 4.2.7 Comparison of Facultative Pond Design Models .....101 4.3 Partial-Mix Aerated Ponds ....................................................103 4.3.1 Partial-Mix Design Model .......................................104 4.3.1.1 Selection of Reaction Rate Constants .......105 4.3.1.2 Influence of Number of Cells ...................105 4.3.1.3 Temperature Effects ..................................106 4.3.2 Pond Configuration ..................................................106 4.3.3 Mixing and Aeration ................................................107 4.4 Complete-Mix Aerated Pond Systems ..................................117 4.4.1 Design Equations ......................................................118 4.4.1.1 Selection of Reaction Rate Constants .......118 4.4.1.2 Influence of Number of Cells ...................119 4.4.1.3 Temperature Effects ..................................119 4.4.2 Pond Configuration ..................................................120 4.4.3 Mixing and Aeration ................................................121 4.4.4 Comparison of Conventional and Metcalf and Eddy Aerated Lagoon Designs .................................126 4.5 ASM1, ASM2, and ASM3 Models ........................................128 4.5.1 Introduction ..............................................................128 4.5.2 Description of Models ..............................................128 © 2010 Taylor & Francis Group, LLC