Second Edition Natural Wastewater Treatment Systems Ronald W Crites E Joe Middlebrooks Robert K Bastian Sherwood C Reed 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 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organization that provides licenses and registration for a variety of users For organizations that have been granted a photocopy 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 Natural Wastewater Treatment Systems: An Overview 1.1 Natural Treatment Processes 1.1.1 Background 1.1.2 Wastewater Treatment Concepts and Performance Expectations 1.1.2.1 Aquatic Treatment Units 1.1.2.2 Wetland Treatment Units 1.1.2.3 Terrestrial Treatment Methods 1.1.2.4 Sludge Management Concepts .5 1.1.2.5 Costs and Energy 1.2 Project Development References Chapter Planning, Feasibility Assessment, and Site Selection 11 2.1 2.2 2.3 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 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 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 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 ix Contents 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 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 On-Site Wastewater Systems 495 for installation and monitoring of on-site treatment and disposal and reuse technologies Examples of five onsite management districts are presented below Stinson Beach, CA Stinson Beach is located in Marin County, California, just north of the Golden Gate Bridge and San Francisco Bay It developed in the late 1800s using on-site systems for wastewater treatment and dispersal In 1961, a survey found that existing on-site systems constituted a public health hazard and the Stinson Beach County Water District was formed in 1962 to provide sewerage services for the area (Crites and Tchobanoglous 1998) A bacteriological survey of the local creek found high coliform organism counts and led to a ban on the use of on-site systems Nine engineering studies were conducted to determine what should be done to correct the situation In each case the proposed plans were rejected because of local opposition or the failure of the plans to meet regulations (Crites and Tchobanoglous 1998) The Onsite Wastewater Management District was formed in 1978 under new state legislation There were 672 discrete on-site systems in Stinson Beach in 1998 ranging from pressure-dosed leachfields to intermittent sand filters The District regulates the permitting, development, design, and repair of the on-site systems and monitors both surface water and groundwater Sea Ranch, CA The Sea Ranch residential community features some of the most exclusive real estate in the country A total of 1500 homes sit on 2500 lots on rugged, rocky land that hugs the California coastline for about 10 miles on either side of the famed Highway in Sonoma County, CA Picturesque views, abundant wildlife, and the feeling of “getting away from it all” are some of the reasons that draw scores of weekend and holiday residents Officials with the Sea Ranch Association estimate that only 600 of the community’s homes are lived in by full-timers — and because more than 1200 of the community’s homes rely on on-site septic systems, the high number of part-time residents can cause serious wastewater problems Sea Ranch is unique because its residents are served by a combination of centralized and decentralized sewer services The 600 homes here that are not connected to on-site septic systems are instead served by one of two wastewater treatment plants owned by the Sonoma County Water Agency The staffers at the Sea Ranch Association Water Co are contracted by the county to maintain and operate the wastewater treatment plants The community’s central treatment plant can handle 27,000 gallons of water per day, while its north plant can take 160,000 gallons daily The ranch uses treated water from the north sanitation zone to irrigate its golf links It uses treated wastewater from the central plant for irrigation The Sea Ranch Onsite Waste Disposal Zone is responsible for record keeping, routine inspections, operating permits, abatement/enforcement, water quality monitoring, reports, and public education Homeowners are responsible for the design, construction, operation, and maintenance of their systems Paradise, CA The Town of Paradise has a population of 27,000 that is served by decentralized treatment systems The town started as a retirement community and then became a bedroom community to the city of Chico Spread across 18 square miles of foothills, the community cherishes its rural atmosphere Several attempts to develop centralized sewers were defeated After the 1992 sewer plan was defeated, an on-site zone became the means for Paradise to manage all the wastewater systems in town (Pinkham et al 2004) © 2010 Taylor & Francis Group, LLC 496 Natural Wastewater Treatment Systems Through the Onsite Wastewater Management Zone, the town requires operating permits for all new and existing systems; adopted design criteria, including special regulations for large systems and innovative systems; set up variance and enforcement procedures; and established a monitoring program Paradise also established a program of initial and periodic operational evaluation of all on-site systems by private evaluators Georgetown Divide PUD, CA Georgetown Divide Public Utilities District serves the area of El Dorado County, California, known as Auburn Lake Trails This Sierra Nevada foothill subdivision is located on 2500 acres Many of the lots are marginally suitable for on-site dispersal of septic tank effluent In 1971 the District was formed in response to environmental concerns about water quality The original intent was for the District to be an interim entity until sufficient housing density made conventional sewering feasible (Crites and Tchobanoglous 1998) However, because of the increasing cost of centralized sewering, improvements in on-site treatment and dispersal technology, and changing philosophy regarding on-site systems as being acceptable wastewater infrastructure, the District continues to provide initial site inspection, design, management, periodic system inspection, and educational and environmental surveillance services to on-site disposal system customers When on-site wastewater disposal systems were proposed, it was discovered that many of the 1800 lots had issues with limited soil depth, high seasonal groundwater, and unfavorable topographic conditions An initial soils investigation, involving over 4000 soil profiles and 6000 percolation tests were conducted so that on-site dispersal systems could be designed to overcome the physical restrictions The District inspectors work with the individual site contractors and homeowners during the process of location, design, and construction of individual on-site systems The District maintains a database of site conditions and enters new systems into the database including design criteria and inspection reports Charlotte County, FL Charlotte County is on the Gulf side of Florida to the south of Saratoga The availability of some 200,000 affordable quarter-acre lots led to rapid growth in the 1970s to the 2000 population of 140,000 (Pinkham et al 2004) Roughly half the lots have access to water distribution, but the original developers only provided sewer service to a smaller portion of the lots In 1993, the county prepared a master sewer plan with an estimated wastewater service cost of $462 million Public reaction was overwhelmingly negative and the county stopped the project In 1997, the county took an alternative approach It enacted a variety of growth management policies It developed “mini” sewer expansions in certain area, established a water-quality monitoring program, developed an ordinance to require advanced treatment (aerobic treatment units (ATUs)) or density-reducing lot combinations for small and waterfront lots, and created a septic system management program Under the ordinance, operating permits and service contracts with licensed maintenance companies are required for all ATUs The ATU ordinance met with initial resistance from realtors and builders who thought its cost would hurt their business, but is now largely accepted © 2010 Taylor & Francis Group, LLC On-Site Wastewater Systems 497 REFERENCES Anderson, D.L., Tyl, M.B., Otis, R.J., Mayer, T.G., and Sherman, K.M (1998) Onsite wastewater nutrient reduction systems (OWNRS) for nutrient sensitive environments, in Proceedings of the Eighth International Symposium on Individual and Small Community Sewage Systems, American Society of Agricultural Engineering, Orlando, FL, March 8–10, 1998 Ball, H.L (1994) Nitrogen reduction in an onsite trickling filter/upflow filter wastewater treatment system, in Proceedings of the Seventh International Symposium on Individual and Small Community Sewage Systems, American Society of Agricultural Engineers, Atlanta, GA, December 11–13, 1994, 499–503 Ball, H.L (1995) Nitrogen reduction in an onsite trickling filter/upflow filter system, in Proceedings of the 8th Northwest Onsite Wastewater Treatment Short Course and Equipment Exhibition, University of Washington, Seattle Beggs, R.A., Tchobanoglous, G., Hills, D., and Crites, R.W (2004) Modeling subsurface drip application of onsite wastewater treatment system effluent, in Proceedings of the Tenth International Symposium on Individual and Small Community Sewage Systems, American Society of Agricultural Engineering, Sacramento, CA, March 21–24, 2004 Bernhart, A.P (1973) Treatment and Disposal of Waste Water from Homes by Soil Infiltration and Evapotranspiration, University of Toronto Press, Toronto, Canada Bishop, P.L and Logsdon, H.S (1981) Rejuvenation of failed soil absorption systems, J Am Soc Chem Eng Environ Eng Div., 107(EE1), 47 Bounds, T., Ball, E.S., and Ball, H.L (2000) Performance of packed bed filters, in Proceedings of the National Onsite Wastewater Recycling Association Conference, Jekyll Island, GA, November 3–6, 1999 Bouwer, H (1978) Groundwater Hydrology, McGraw-Hill, New York Cagle, W.A and Johnson, L.A (1994) Onsite intermittent sand filter systems: A regulatory/ scientific approach to their study in Placer County, California, in Proceedings of the Seventh International Symposium of Individual and Small Community Sewage Systems, American Society of Agricultural Engineers, Atlanta, GA, December 11–13, 1994 California Resources Agency (1994) Graywater Guide, The Resources Agency, Sacramento, CA Christopherson, S.H., Anderson, J.L., and Gustafson, D.M (2001) Evaluation of recirculating sand filters in Minnesota, in Proceedings of the Ninth International Symposium on Individual and Small Community Sewage Systems, American Society of Agricultural Engineering, Ft Worth, TX, March 11–14, 2001 Converse, J.C and Tyler, E.J (1995) Aerobically treated domestic wastewater to renovate failing septic tank-soil absorption fields, in Proceedings of the Eighth Northwest Onsite Wastewater Treatment Short Course and Equipment Exhibition, University of Washington, Seattle Crites, R.W and Tchobanoglous, G (1998) Small and Decentralized Wastewater Management Systems, McGraw-Hill, New York Crites, R.W., Lekven, C.C., Wert, S., and Tchobanoglous, G (1997) A decentralized waste water system for a small residential development in California, Small Flows J., 3(1), 3–11 Crites, R.W., Reed, S.C., and Bastian, R.K (2000) Land Treatment Systems for Municipal and Industrial Wastes, McGraw-Hill, New York Darby, J., Tchobanoglous, G., Nor, M.A., and Maciolek, D (1996) Shallow intermittent sand filtration: Performance evaluation, Small Flows J., 2(1), 3–15 Elliott, R (2001) Evaluation of the use of crushed recycled glass as a filter medium, Water Eng Manage., July/August Furman, T.S., Calaway, W.T., and Gratham, G.R (1955) Intermittent sand filters: multiple loadings, Sewage Indust Wastes, 27(3), 261–276 Grantham, G.R., Emerson, D.L., and Henry, A.K (1949) Intermittent sand filter studies, Sewage Indust Wastes, 21(6), 1002–1015 © 2010 Taylor & Francis Group, LLC 498 Natural Wastewater Treatment Systems Hargett, D.L., Tyler, E.J., Converse, J.C., and Apfel, R.A (1985) Effects of hydrogen peroxide as a chemical treatment for clogged wastewater absorption systems, in Onsite Wastewater Treatment, ASAE no 701P0101, American Society of Agricultural Engineers, St Joseph, MI Harkin, J.N and Jawson, M.D (1977) Clogging and unclogging of septic system seepage beds, in Proceedings of the Second Illinois Symposium on Private Sewage Disposal Systems, Illinois Department of Public Health, Springfield Hines, M.J and Favreau, R.F (1974) Recirculating sand filter: An alternative to traditional sewage absorption system, in Proceedings of the National Home Sewage Disposal Symposium, Chicago, December 9–10, 1974, 130–136 Ingham, A.T (1980) Guidelines for Mound Systems, California State Water Resources Control Board, Sacramento, CA Jantrania, A.R., Sheu, K.C., Cooperman, A.N., and Pancorbo, O.C (1998) Performance evaluation of alternative systems: Gloucester, MA, demonstration project, in Proceedings of the Eighth International Symposium on Individual and Small Community Sewage Systems, American Society of Agricultural Engineering, Orlando, FL, March 8–10, 1998 Leverenz, H., Tchobanoglous, G., and Darby, J.L (2002) Review of Technologies for the Onsite Treatment of Wastewater in California, Report No 02-2, prepared for the California State Water Resources Control Board, Sacramento, CA, Department of Civil and Environmental Engineering, University of California, Davis Loomis, G., Dow, D., Jobin, J., Green, L., Herron, E., Gold, A., Stolt, M., and Blezejewski, G (2004) Long-term treatment performance of innovative systems, in Proceedings of the Tenth International Symposium on Individual and Small Community Sewage Systems, American Society of Agricultural Engineering, Sacramento, CA, March 21–24, 2004 Mancl, K.M and Peeples, J.A (1991) One hundred years later: reviewing the work of the Massachusetts State Board of Health on the intermittent sand filtration of wastewater from small communities, in Proceedings of the Sixth National Symposium Individual and Small Community Sewage Systems, ASAE Publ No 10-91, American Society of Agricultural Engineers, St Joseph, MI Mickelson, M.J., Converse, C., and Tyler, E.J (1989) Hydrogen peroxide renovation of clogged wastewater soil absorption systems in sands, Trans Am Soc Agric Eng., 32(5), 1662–1668 Nolte Associates (1992a) Literature Review of Recirculating and Intermittent Sand Filters: Operation and Performance, Town of Paradise, California, prepared for the California Regional Water Quality Control Board, Sacramento Nolte Associates (1992b) Manual for the Onsite Treatment of Wastewater, Town of Paradise, California, Sacramento Nolte Associates (1994) Fatal Flaw Analysis of Onsite Alternatives for Los Osos, California, prepared for Metcalf and Eddy and San Luis Obispo County, Sacramento, CA Nor, M.A (1991) Performance of Intermittent Sand Filters: Effects of Hydraulic Loading Rate, Dosing Frequency, Media Effective Size, and Uniformity Coefficient, Ph.D thesis, Department of Civil Engineering, University of California, Davis Otis, R.J (1982) Pressure distribution design for septic tank systems, J Am Soc Chem Eng Environ Eng Div., 108(EE1), 123 Patterson, R.A (1997) Domestic wastewater and sodium factor, in Site Characterization and Design of Onsite Septic Systems, Bedinger, M.S et al., Eds., ASTM STP 1324, American Society for Testing and Materials, Philadelphia Pinkham, R D., Magliaro, J., and Kinsley, M (2004) Case Studies of Economic Analysis and Community Decision Making for Decentralized Wastewater Systems, Project No WU-HT-02-03, prepared for the National Decentralized Water Resources Capacity Development Project, Washington University, St Louis, MO, by Rocky Mountain Institute, Snowmass, CO © 2010 Taylor & Francis Group, LLC On-Site Wastewater Systems 499 Prince, R.N and Davis, M.E (1988) Onsite System Management, paper presented at the Third Annual Midyear Conference of the National Environmental Health Association, Mobile, AL Reed, S.C (1993) Subsurface Flow Constructed Wetlands for Wastewater Treatment: A Technology Assessment, EPA 832-R-93-001, U.S Environmental Protection Agency, Washington, DC Reed, S.C., Crites, R.W., and Middlebrooks, E.J (1995) Natural Systems for Waste Management and Treatment, 2nd ed., McGraw-Hill, New York Ronayne, M.A., Paeth, R.A., and Wilson, S.A (1984) Oregon Onsite Experimental Systems Program, Oregon Department of Environmental Quality, EPA/600/14, U.S Environmental Protection Agency, Cincinnati, OH Sandy, A.T., Sack, W.A., and Dix, S.P (1988) Enhanced nitrogen removal using a modified recirculating sand filter (RSF2), in Proceedings of the Fifth National Symposium on Individual and Small Community Sewage Systems, American Society of Agricultural Engineers, Chicago, December 14–15, 1987 Siegrist, R.L (1987) Hydraulic loading rates for soil absorption systems based on waste water quality, in Proceedings of the Fifth National Symposium on Individual and Small Community Sewage Systems, American Society of Agricultural Engineers, Chicago, December 14–15, 1987 Tchobanoglous, G., Burton, F.L., and Stensel, H.D (2003) Wastewater Engineering, Treatment, and Reuse, 4th ed., McGraw-Hill, New York USEPA (1980) Design Manual: Onsite Wastewater Treatment and Disposal Systems, Municipal Environmental Research Laboratory, U.S Environmental Protection Agency, Cincinnati, OH USEPA (2002) Onsite Wastewater Treatment Systems Manual, EPA/625/R-00/008, Office of Water, Office of Research and Development, U.S Environmental Protection Agency, Cincinnati, OH USEPA (2003) Voluntary National Guidelines for Management of Onsite and Clustered (Decentralized) Wastewater Treatment Systems, Office of Water, EPA 832-B-03-001 Cincinnati, OH Washington State DOH (1996) Onsite Sewage System Monitoring Programs in Washington State, Community Environmental Health Programs, Washington State Department of Health, Olympia, WA Wert, S (personal communication, 1997) Roseburg, OR Winneberger, J.H.T (1984) Septic-Tank Systems: A Consultant’s Toolkit Vol Subsurface Disposal of Septic-Tank Effluents, Butterworth, Boston WERF (2007) Establishing Successful RMEs, prepared by Institute for Sustainable Futures at the University of Technology Sydney in Australia and Stone Environmental, Inc., Water Environment Research Foundation, Alexandria, VA WEF (2010) Natural Systems for Wastewater Treatment, Manual of Practice FD-16, Third Ed Water Environment Federation, Alexandria, VA © 2010 Taylor & Francis Group, LLC Appendix 1: Metric Conversion Factors (SI to U.S Customary Units) Multiply the SI Unit Name Hectare (10,000 m2) Square centimeter Square kilometer Square kilometer Square meter Square meter Kilojoule Joule Megajoule Conductance, thermal Conductivity, thermal Heat-transfer coefficient Latent heat of water Specific heat, water To Obtain the U.S Unit Symbol by Symbol Name cm2 km2 km2 m2 m2 Area 2.4711 0.1550 0.3861 247.1054 10.7639 1.1960 ac in.2 mi2 ac ft2 yd2 Acre Square inch Square mile Acre Square foot Square yard Energy 0.9478 2.7778 × 10–7 0.3725 0.1761 0.5778 0.1761 — Btu kWh hp·hr Btu/hr·ft2·°F Btu/hr·ft·°F Btu/hr·ft2·°F 144 Btu/lb British thermal unit Kilowatt-hour Horsepower-hour Conductance Conductivity Heat-transfer coefficient Latent heat of water 1.007 Btu/ lb·°F Specific heat of water kJ J MJ W/m2·°C W/m·°C W/m2·°C 344,944 J/kg 4215 J/kg·°C — Cubic meters per day Cubic meters per day Cubic meters per second Cubic meters per second Cubic meters per second Liters per second m3/d m3/d m3/d m3/s m3/s L/s Flow Rate 264.1720 2.6417 × 10–4 35.3157 22.8245 15.8503 22.8245 gal/d mgd ft3/s mgd gal/min gal/d Gallons per day Million gallons per day Cubic feet per second Million gallons per day Gallons per minute Gallons per day Centimeter Kilometer Meter Meter Meter Millimeter cm km m m m mm Length 0.3937 0.6214 39.3701 3.2808 1.0936 0.03937 in mi in ft yd in Inch Mile Inch Foot Yard Inch 501 © 2010 Taylor & Francis Group, LLC 502 Appendix Multiply the SI Unit To Obtain the U.S Unit Name Symbol by Symbol Name Gram Gram Kilogram Megagram (103 kg) (metric ton) Megagram g g kg Mg (mt) Mass 0.0353 0.0022 2.2046 1.1023 oz lb lb ton (t) Ounce Pound Pound Ton (short: 2000 lb) Mg 0.9842 ton Ton (long: 2240 lb) Kilowatt kW Power 0.9478 Btu/s Kilowatt kW 1.3410 hp British thermal units per second Horsepower Pa (N/m2) Pressure 1.4505 × 10–4 lb/in.2 Pounds per square inch °C K Temperature 1.8 (°C) + 32 1.8 (K) – 459.67 °F °F Degree Fahrenheit Degree Fahrenheit Pascal Degree Celsius Kelvin Kilometers per second Meters per second km/s m/s Velocity 2.2369 3.2808 mi/hr ft/s Miles per hour Feet per second Cubic centimeter Cubic meter Cubic meter Cubic meter Cubic meter Liter Liter Liter Megaliter (L × 106) cm3 m3 m3 m3 m3 L L L ML Volume 0.0610 35.3147 1.3079 264.1720 8.1071 × 10–4 0.2642 0.0353 33.8150 0.2642 in.3 ft3 yd3 gal ac-ft gal ft2 oz MG Cubic inch Cubic foot Cubic yard Gallon Acre-foot Gallon Square foot Ounce Million gallons © 2010 Taylor & Francis Group, LLC Appendix 2: Conversion Factors for Commonly Used Design Parameters Multiply the SI Unit To Obtain the U.S Customary Unit Parameter Symbol by Symbol Parameter Cubic meters per second Cubic meters per day Kilogram per hectare Metric ton per hectare Cubic meter per hectare per day Kilograms per square meter per day Cubic meter (solids) per 103 cubic meters (liquid) Cubic meters (liquid) per square meter (area) Grams (solids) per cubic meter Cubic meters (air) per cubic meter (liquid) per minute Kilowatts per 103 cubic meters (tank volume) Kilograms per cubic meter Cubic meter per capita Bushels per hectare m3/s m3/d kg/ha Mg/ha m3/ha·d 22.727 264.1720 0.8922 0.4461 106.9064 mgd gal/d lb/ac ton/ac gal/ac·d Million gallons per day Gallons per day Pounds per acre Tons (short) per acre Gallons per acre per day kg/m2·d 0.2048 lb/ft2·d Pounds per square foot per day ft3/MG Cubic feet per million gallons m3/103 m3 133.681 m3/m2 24.5424 gal/ft2 Gallons per square foot g/m3 8.3454 lb/MG Pounds per million gallons ft3/103·min m3/m2 1000.0 kW/103·m3 0.0380 hp/103 ft3 Cubic feet of air per minute per 1000 ft3 Horsepower per 1000 ft3 kg/m3 m3/capita bu/ha 62.4280 35.3147 0.4047 lb/103 ft3 ft3/capita bu/ac Pounds per 1000 ft3 Cubic feet per capita Bushels per acre 503 © 2010 Taylor & Francis Group, LLC Appendix 3: Physical Properties of Water Temperature (°C) Density (kg/m3) Dynamic Viscosity × 103 (N·s/m2) Kinematic Viscosity (g) × 106 (m2/s) 10 15 20 25 30 40 50 60 70 80 90 100 999.8 1000.0 999.7 999.1 998.2 997.0 995.7 992.2 988.0 983.2 977.8 971.8 965.3 958.4 1.781 1.518 1.307 1.139 1.002 0.890 0.798 0.653 0.547 0.466 0.404 0.354 0.315 0.282 1.785 1.519 1.306 1.139 1.003 0.893 0.800 0.658 0.553 0.474 0.413 0.364 0.326 0.294 505 © 2010 Taylor & Francis Group, LLC Appendix 4: Dissolved Oxygen Solubility in Freshwater Temperature (°C) 10 11 12 13 14 15 Dissolved Oxygen Solubility (mg/L) Temperature (°C) Dissolved Oxygen Solubility (mg/L) 14.62 14.23 13.84 13.48 13.13 12.80 12.48 12.17 11.87 11.59 11.33 11.08 10.83 10.60 10.37 10.15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 9.95 9.74 9.54 9.35 9.17 8.99 8.83 8.68 8.53 8.38 8.22 8.07 7.92 7.77 7.63 Note: Saturation values of dissolved oxygen when exposed to dry air containing 20.90% oxygen under a total pressure of 760 mmHg 507 © 2010 Taylor & Francis Group, LLC WATER ENGINEERING “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 wastewater This updated edition will only enhance its recognition as an industry 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 methods for the treatment and management of wastewater Based on work by prominent experts in natural waste treatment, this text provides a thorough explanation on how soil and plants can successfully sustain microbial populations in the treatment of wastewater Determining that natural systems cost less to construct and operate and require less energy than mechanical treatment alternatives, the text also explains how these processes produce lower amounts of residual solids and use little or no chemicals What’s New in the Second Edition: This revised edition includes current design and regulatory and operational developments in the natural wastewater treatment field It provides detailed examples and analyses along with significant operational data in each chapter It also considers how processes provide passive treatment with a minimum of mechanical elements and describes new approaches to partially mixed ponds, including dual-powered aeration ponds • Introduces the planning procedures and treatment mechanisms responsible for treatment in ponds, wetlands, land applications, and soil absorption systems • Presents design criteria and methods of pond treatment and pond effluent upgrading • Describes constructed wetlands design procedures, process applications, treatment performance data, and land treatment concepts and design equations • Provides new case studies of decentralized natural treatment and reuse systems • Includes examples of onsite wastewater management district operations Designed for practicing wastewater engineers and scientists involved in the planning, design, and operation of ponds, wetlands, land treatment, biosolids, and onsite soilbased treatment systems, the book integrates many natural treatment systems into one single source K18980 an informa business w w w c r c p r e s s c o m 6000 Broken Sound Parkway, NW Suite 300, Boca Raton, FL 33487 711 Third Avenue New York, NY 10017 Park Square, Milton Park Abingdon, Oxon OX14 4RN, UK w w w c rc p r e s s c o m