Background Prerequisites The background prerequisites for this textbook are general chemistry, mathematics up to calculus, and fluid mechanics. In very few instances, an elementary knowledge of calculus is used, but mostly the mathematical treatment makes intensive use of algebra. In fluid mechanics, the only sophisticated topic used is the Reynolds trans- port theorem. Although this topic is covered in an undergraduate course in fluid mechanics, it was thought advantageous to review it here. The other background prerequisite is general chemistry. Environmental engineering students and civil engi- neering students, in particular, seem to be very weak in chemistry. This part will therefore also provide a review of this topic. Depending upon the state of knowledge of the students, however, this part may or may not be discussed. This state of knowledge may be ascertained by the instructor in the very first few days of the course, and he or she can tailor the discussions accordingly. The contents of this “Background Prerequisites” section are not really physical– chemical treatment but just background knowledge to comfortably understand the method of approach used in the book. This book is analytical and therefore must require extensive use of the pertinent chemistry, mathematics, and fluid mechanics. This section contains two chapters: “Introduction” and “Background Chemistry and Fluid Mechanics.” TX249_Frame_Intro Page 1 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero Introduction This book is titled Physical–Chemical Treatment of Water and Wastewater . This chapter begins by defining wastewater and physical–chemical treatment of water and wastewater and treats briefly the coverage. It also addresses the unit operations and unit processes. In addition, in the environmental engineering field, construction of water and wastewater treatment plants and the requirements of their levels of performance are mostly driven by government laws and regulations. For example, the Clean Water Act mandates construction of wastewater treatment facilities that, at least, must produce the secondary level of treatment. The Safe Water Drinking Water Act also requires performance of treatment plants that produce drinking water of quality free from harmful chemicals and pathogens. For these reasons, the Clean Water Act and the Safe Drinking Water Act are discussed at length, detailing their developments and historical perspectives. WASTEWATER Wastewater is the spent water after homes, commercial establishments, industries, public institutions, and similar entities have used their waters for various purposes. It is synonymous with sewage , although sewage is a more general term that refers to any polluted water (including wastewater), which may contain organic and inor- ganic substances, industrial wastes, groundwater that happens to infiltrate and to mix with the contaminated water, storm runoff, and other similar liquids. A certain sewage may not be a spent water or a wastewater. The keyword in the definition of wastewater is “used” or “spent.” That is, the water has been used or spent and now it has become a waste water . On the other hand, to become a sewage, it is enough that water becomes polluted whether or not it had been used. When one uses the word wastewater, however, the meaning of the two words is blended such that they now often mean the same thing. Wastewater equals sewage . PHYSICAL–CHEMICAL TREATMENT OF WATER AND WASTEWATER What is physical–chemical treatment of water and wastewater? The dictionary defines physical as having material existence and subject to the laws of nature. Chemical , on the other hand, is defined as used in, or produced by chemistry. Being used in and produced by chemistry implies a material existence and is subject to the laws of nature. Thus, from these definitions, chemical is physical. The fact that chemical is physical has not, however, answered the question posed. TX249_Frame_Intro Page 3 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero To explore the question further, we go to the definition of chemistry. Chemistry is defined as the branch of science that deals with the composition, structure, and properties of substances and the transformation that they undergo. Now, from this definition can be gleaned the distinguishing feature of chemical—the transformation that the substance undergoes. The transformation changes the original substance into an entirely different substance after the transformation. Chemical transformation can be distinguished from physical transformation. In physical transformation, although also involving a change, the change is only in appearance but not in substance. For example, FeO in the beginning is still FeO in the end; the size of the particles may have changed, however, during the process. We now define physical treatment of water and wastewater as a process applied to water and wastewater in which no chemical changes occur. We also define chemical treatment of water and wastewater as a process applied to water and wastewater in which chemical changes occur. Gleaning from these definitions of physical and chemical treatments, in the overall sense, physical–chemical treatment of water and wastewater is a process applied to water and wastewater in which chemical changes may or may not occur. UNIT OPERATIONS AND UNIT PROCESSES Figure 1 shows the schematic of a conventional wastewater treatment plant using primary treatment. Raw wastewater is introduced either to the screen or to the comminutor. The grit channel removes the larger particles from the screened sewage, and the primary clarifier removes the larger particles of organic matter as well as inorganic matter that escapes removal by the grit channel. Primary treated sewage is then introduced to a secondary treatment process train downstream (not shown) where the colloidal and dissolved organic matter are degraded by microorganisms. The scheme involves mere physical movement of materials, no chemical or biological changes occur. In addition, the function of the various operations in the scheme, such as screening, may be applied not only to the primary treatment of sewage as the figure indicates but to other plant operations as well. For example, bagasse may be screened from sugar cane juice in the expression of sugar in a sugar mill, or the larger particles resulting from the cleaning of pineapples in a pineapple factory may be screened from the rest of the wastewater. To master the function of screening, it is not necessary that this be studied in a wastewater treatment plant, in FIGURE 1 A primary treatment system. Raw sewage Comminutor Grit channel Screen Primary clarifier Effluent Sludge TX249_Frame_Intro Page 4 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero Introduction 5 a sugar mill, or in a pineapple factory. It can be studied in any setting where screens are used. Furthermore, the functions of the operation of the primary clarifier may be applied not only to the treatment of sewage as indicated in the schematic but also to the clarification in a water treatment plant, as well as in the clarification of tailings in a mining operation. Similar statements may be made about the operation of the grit channel. In other words, to master the function of clarification and grit removal, it is not necessary that these be studied in a sewage treatment plant or in a water treatment plant. It can be studied in any setting where clarifiers and grit removal are used. The foregoing operations are physical; they are therefore physical treatments. These physical treatments are called unit operations and as gleaned from the previous discussion they may be defined as physical treatments that are identified only accord- ing to their functions without particular reference to the location of the units utilizing the functions. For example, screening may be studied without particular reference to any sugar mills or pineapple factories. The unit operations of clarification may be studied without particular reference to any wastewater or water treatment plants or mining operations. The unit operations of grit removal may also be studied without particular reference to any sewage plant but only to any setting where grit removal is involved. The unit operations discussed previously are all physical operations. In the biological or chemical scene where materials are changed, unit operations have counterparts called unit processes . Examples of unit processes are coagulation and biological oxidation . In coagulation, a chemical called coagulant undergoes a chem- ical reaction. This chemical reaction may occur in any plant or factory or any location at all where the function of the chemical reaction in coagulation is utilized. For example, coagulation is employed in water treatment to enhance the settling of the turbidity of raw waters. Coagulation may also be used in the clarification of sugar cane juice to remove the fibers that the juice may contain. The other unit process, biological oxidation, is used in sewage treatment; it may also be used in biofiltration applied in water treatment. The biological reaction that occurs in either sewage treatment or biofiltration are the same. In other words, the function of the biological reaction is the same whether the reaction occurs in sewage treatment or in biofiltration. Coagulation and biological oxidation are identified on the basis of the function of their characteristic chemical or biological reactions irrespective of the plant, factory, or any other location that uses the reactions. The function of a coagulation reaction is coagulation whether the reaction occurs in a water treatment plant or in a sugar plant; and the function of a biological oxidation reaction is biological oxidation whether the reaction occurs in a sewage treatment plant or in a water treatment plant. The setting is immaterial; what is of concern is the function of the chemical reaction. Unit processes may therefore be defined as chemical (or biolog- ical) treatments that are identified only according to the functions of the chemical (or biological) reactions irrespective of where the units utilizing the reactions are occurring. TX249_Frame_Intro Page 5 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero 6 Physical–Chemical Treatment of Water and Wastewater COVERAGE This book is divided into four general parts and addresses important topics on the physical–chemical treatment of water and wastewater. The “first” part is titled Background Prerequisites. Its contents are not really physical–chemical treatment but just background knowledge to comfortably understand the method of approach used in the book. This book is analytical and therefore requires the use of pertinent chemistry, mathematics, and fluid mechanics. Relevant prerequisite topics are dis- cussed in this part. Part I, Characteristics of Water and Wastewater, covers the chapters on quantity and constituent physical and chemical characteristics of water and wastewater. Part II, Unit Operations of Water and Wastewater Treatment, includes the chapters on flow measurements and flow and quality equalization; pumping; screening, sedimentation, and flotation; mixing and flocculation; conventional filtration; advanced filtration and carbon adsorption; and aeration and stripping. Part III, Unit Processes of Water and Wastewater Treatment, includes the chapters on coagulation; water softening; chem- ical stabilization; removal of iron and manganese; removal of phosphorus; removal of nitrogen by nitrification–denitrification; ion exchange; and disinfection. Removal of nitrogen by nitrification–denitrification, on the surface, is a biological process. To control the process, however, its intrinsic chemical reactions must be unraveled and totally understood. The treatment (as used in this textbook) therefore turns toward being chemical in nature. The organisms only serve as mediators (i.e., the producer of enzymes needed for the reaction). Thus, on the most fundamental level, nitrogen removal by nitrification–denitrification is a chemical process (more, accu- rately, a biochemical process), which is subsequently included as a chapter in Part III of this book. CLEAN WATER ACT To gain a broader perspective of the Clean Water Act, it is important to know about the United States Code (USC).* This code is a consolidation and codification of the general and permanent laws of the United States. It contains several titles; in one of these titles, the Clean Water Act is codified. Because many of the general and permanent laws required to be incorporated into the code are inconsistent, redundant, and obsolete, the Office of the Law Revision Counsel of the House of Representatives revises for enactment into law each title of the code. This process is called positive law codification . Positive law codification is the process of preparing a bill and enacting it into law, one title at a time, a revision and restatement of the general and permanent laws of the United States. This codification does not change the meaning or legal effect of the statute but removes ambiguities, contradictions, and other imperfections from the law. Certain titles of the code have now been enacted into positive law, and pursuant to Section 204 of Title 1 of the code, the text of these titles is legal evidence of the law. The other titles of the code that have not been * The United States Code itself is public domain. Portions of the code can be used and redistributed without permission from the U.S. Government Printing Office. TX249_Frame_Intro Page 6 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero Introduction 7 enacted into positive law are prima facie evidence of the laws contained in these titles. Table 1 shows the listing of all the titles of the USC. Refer to Table 1. The codification of the Clean Water Act is within Title 33, Navigation and Navigable Waters. This title contains 41 chapters, the first chapter being Navigable Waters Generally and the 41st chapter being National Coastal Monitoring. Chapter 26 of this title is Water Pollution Prevention and Control. This is the codification of the Clean Water Act. Each title of the USC is divided into several sections. Title 33, of course, starts with Section 1, which is under Chapter 1, Navigable Waters Generally. Chapter 26 starts at Section 1251 and ends at Section 1387. A portion of the USC is cited by specifying the title number before the USC and the section or the range of sections after the USC. For example, 33 USC 1251-1387 is the codification of the Clean Water Act. Environmental pollution is global. Both developed and developing countries all experience this problem. These countries therefore enact laws and regulations to TABLE 1 The United States Code Title 1 General Provisions Title 26 Internal Revenue Code Title 2 The Congress Title 27 Intoxicating Liquors Title 3 The President Title 28 Judiciary and Judicial Procedure Title 4 Flag and Seal, Seat of Government, and the States Title 29 Labor Title 30 Mineral Lands and Mining Title 5 Government Organization and Employees Title 31 Money and Finance Title 32 National Guard Title 6 Surety Bonds (repealed) Title 33 Navigation and Navigable Waters Title 7 Agriculture Title 34 Navy (repealed) Title 8 Aliens and Nationality Title 35 Patents Title 9 Arbitration Title 36 Patriotic Societies and Observances Title 10 Armed Forces Title 37 Pay and Allowances of the Uniformed ServicesTitle 11 Bankruptcy Title 12 Banks and Banking Title 38 Veterans’ Benefits Title 13 Census Title 39 Postal Service Title 14 Coast Guard Title 40 Public Buildings, Property, and Works Title 15 Commerce and Trade Title 41 Public Contracts Title 16 Conservation Title 42 The Public Health and Welfare Title 17 Copyrights Title 43 Public Lands Title 18 Crimes and Criminal Procedure Title 44 Public Printing and Documents Title 19 Customs Duties Title 45 Railroads Title 20 Education Title 46 Shipping Title 21 Food and Drugs Title 47 Telegraphs, Telephones, and Radiotelegraphs Title 22 Foreign Relations and Intercourse Title 48 Territories and Insular Possessions Title 23 Highways Title 49 Transportation Title 24 Hospitals and Asylums Title 50 War and National Defense Title 25 Indians TX249_Frame_Intro Page 7 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero 8 Physical–Chemical Treatment of Water and Wastewater control the continuing pollution of the environment. In the United States, the passage of the Rivers and Harbors Act of 1899 may be considered as the first law controlling water pollution. Subsequently, the Federal Water Pollution Control Act, codified as 33 U.S.C. 1251-1387, was passed in 1948. The Federal Water Pollution Control Act is the full name of the Clean Water Act mentioned in the previous paragraphs. This Act is the principal law governing pollution of surface waters of this country. The following years show various amendments to this act: 1956, 1961, 1965, 1966, and 1970; but it was in 1972 that the act was totally revised by amendments to have taken practically its current shape. The 1972 legislation spelled out ambitious programs for water quality improvement that have since been expanded by various additional amendments. Congress made certain fine-tuning amendments in 1977, revised portions of the law in 1981, and enacted further amendments in 1987, the last year that the act was amended. Table 2 traces the dates of the major amendments to the Clean Water Act and Table 3 summarizes the major sections of the Act (indicated in the second column) as codified in the corresponding sections of the USC (first column). The following events were common before 1972: Lake Erie was dying; the Chesapeake Bay was deteriorating rapidly; and the Potomac River was clogged with blue-green algae blooms. Many of the rivers were like open sewers, and sewage frequently washed up on shores. Fish kills were a common sight. Wetlands were disappearing. The Cuyahoga River in Cleveland, Ohio, was burned because of gross pollution due to a discharge of oil. To stop this widespread water pollution, in 1972, Congress enacted the first comprehensive national clean water legislation— the Federal Water Pollution Control Act Amendments of 1972 . The Clean Water Act focuses on improving the water quality of the nation. It provides for establishment of standards, development of technical tools, and financial assistance to address the causes of pollution and poor water quality, including municipal and industrial wastewater discharges, nonpoint source runoff pollution TABLE 2 Clean Water Act (Chapter 26) and Major Amendments Year Act Public Law 1948 Federal Water Pollution Control Act P. L. 80-845 (June 30, 1948) 1956 Water Pollution Control Act of 1956 P. L. 84-660 (July 9, 1956) 1961 Federal Water Pollution Control Act Amendments P.L. 87-88 1965 Water Quality Act of 1965 P.L. 89-234 1966 Clean Water Restoration Act P.L. 89-753 1970 Water Quality Improvement Act of 1970 P.L. 91-224, Part I 1972 Federal Water Pollution Control Act Amendments P.L. 92-500 1977 Clean Water Act of 1977 P.L. 95-217 1981 Municipal Wastewater Treatment Construction Grants Amendments P.L. 97-117 1987 Water Quality Act of 1987 P.L. 100-4 TX249_Frame_Intro Page 8 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero Introduction 9 TABLE 3 Major U.S. Code Sections of the Clean Water Act Code Section Subchapter Subchapter I—Research and Related Programs 1251 Congressional declaration of goals and policy, Sec. 101 1252 Comprehensive programs for water pollution control, Sec. 102 1253 Interstate cooperation and uniform laws, Sec. 103 1254 Research, investigations, training and information, Sec. 104 1255 Grants for research and development, Sec. 105 1256 Grants for pollution control programs, Sec. 106 1257 Mine water pollution demonstrations, Sec. 107 1258 Pollution control in the Great Lakes, Sec. 108 1259 Training grants and contracts, Sec. 109 1260 Applications for training grants and contracts, allocations, Sec. 110 1261 Scholarships, Sec. 111 1262 Definitions and authorization, Sec. 112 1263 Alaska village demonstration project, Sec. 113 1265 In-place toxic pollutants, Sec. 115 1266 Hudson River reclamation demonstration project, Sec. 116 1267 Chesapeake Bay, Sec. 117 1268 Great Lakes, Sec. 118 1269 Long Island Sound, Sec. 119 1270 Lake Champlain management conference, Sec. 120 Subchapter II—Grants for Construction of Treatment Works 1281 Congressional declaration of purpose, Sec. 201 1282 Federal share, Sec. 202 1283 Plans, specifications, estimates, and payments, Sec. 203 1284 Limitations and conditions, Sec. 204 1285 Allotment of grant funds, Sec. 205 1286 Reimbursement and advanced construction, Sec. 206 1287 Authorization of appropriations, Sec. 207 1288 Areawide waste treatment management, Sec. 208 1289 Basin planning, Sec. 209 1290 Annual survey, Sec. 210 1291 Sewage collection system, Sec. 211 1292 Definitions, Sec. 212 1293 Loan guarantees, Sec. 213 1294 Wastewater recycling and reuse information and education, Sec. 214 1295 Requirements for American materials, Sec. 215 1296 Determination of priority, Sec. 216 1297 Guidelines for cost effective analysis, Sec. 217 1298 Cost effectiveness, Sec. 218 1299 State certification of projects, Sec. 219 ( continued ) TX249_Frame_Intro Page 9 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero 10 Physical–Chemical Treatment of Water and Wastewater TABLE 3 ( Continued ) Major U.S. Code Sections of the Clean Water Act Code Section Subchapter Subchapter III—Standards and Enforcement 1311 Effluent Limitations, Sec. 301 1312 Water quality-related effluent limitations, Sec. 302 1313 Water quality standards and implementation plans, Sec. 303 1314 Information and guidelines, Sec. 304 1315 State reports on water quality, Sec. 305 1316 National standards of performance, Sec. 306 1317 Toxic and pretreatment effluent standards, Sec. 307 1318 Records and reports, inspections, Sec. 308 1319 Enforcement, Sec. 309 1320 International pollution abatement, Sec. 310 1321 Oil and hazardous substance liability, Sec. 311 1322 Marine sanitation devices, Sec. 312 1323 Federal facility pollution control, Sec. 313 1324 Clean lakes, Sec. 314 1325 National study commission, Sec. 315 1326 Thermal discharges, Sec. 316 1327 Omitted (alternative financing), Sec. 317 1328 Aquaculture, Sec. 318 1329 Nonpoint source management program, Sec. 319 1330 National estuary study, Sec. 320 Subchapter IV—Permits and Licenses 1341 Certification, Sec. 401 1342 National pollutant discharge elimination system, Sec. 402 1343 Ocean discharge criteria, Sec. 403 1344 Permits for dredge and fill materials, Sec. 404 1345 Disposal or use of sewage sludge, Sec. 405 Subchapter V—General Provisions 1361 Administration, Sec. 501 1362 Definitions, Sec. 502 1363 Water pollution control advisory board, Sec. 503 1364 Emergency powers, Sec. 504 1365 Citizen suits, Sec. 505 1366 Appearance, Sec. 506 1367 Employee protection, Sec. 507 1368 Federal procurement, Sec. 508 1369 Administrative procedure and judicial review, Sec. 509 1370 State authority, Sec. 510 1371 Authority under other laws and regulations, Sec. 511 1372 Labor standards, Sec. 513 1373 Public health agency coordination, Sec. 514 1374 Effluent standards and water quality information advisory committee, Sec. 515 TX249_Frame_Intro Page 10 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero Introduction 11 from urban and rural areas, and habitat destruction. For example, the Clean Water Act requires: • Establishment of water quality standards by the states and tribes for their waters and development of pollution control programs to achieve them • Establishment of a minimum level of wastewater treatment for all publicly owned facilities • Meeting of performance standards by major industries to ensure pollution control • Funding by the Federal government to states and communities to help meet their wastewater infrastructure needs • Protection of wetlands and other aquatic habitats through a permitting process that ensures environmentally sound development The 1972 Clean Water Act declared as its objective the restoration and mainte- nance of the chemical, physical, and biological integrity of the nation’s waters. Two goals were established: (1) zero discharge of pollutants by 1985; and (2) as an interim goal, water quality that is fishable and swimmable by the middle of 1983. These goals were, of course, not being met. Aside from research and related programs provision, essentially, the Clean Water Act consists of three major parts: 1. Regulatory requirements under the title of Subchapter III 2. Provisions that authorize federal financial assistance for municipal sewage treatment plant construction under the titles of Subchapters II and VI 3. Permits and enforcement under the titles of Subchapters IV and III, respectively. In terms of historical perspective, these parts are discussed in sequence next. TABLE 3 ( Continued ) Major U.S. Code Sections of the Clean Water Act Code Section Subchapter 1375 Reports to Congress, Sec. 516 1376 Authorization of appropriations, Sec. 517 1377 Indian tribes, Sec. 518 Subchapter VI—State Water Pollution Control Revolving Funds 1381 Grants to states for establishment of revolving funds, Sec. 601 1382 Capitalization grant agreements, Sec. 602 1383 Water pollution control revolving loan funds, Sec. 603 1384 Allotment of funds, Sec. 604 1385 Corrective actions, Sec. 605 1386 Audits, reports, fiscal controls, intended use plan, Sec. 606 1387 Authorization of appropriations, Sec. 607 TX249_Frame_Intro Page 11 Friday, June 14, 2002 1:45 PM © 2003 by A. P. Sincero and G. A. Sincero [...]... nature of wetlands, the wetlands permit program is a controversial part of the law Some of the wetlands are privately owned If the owner wants to develop the area, the law can intrude and impede private decision of what to do with the property On the other hand, environmentalists seek more protection for remaining wetlands and want limits on activities that can take place there The other sections of the... MCLGs as feasible and are based upon treatment technologies, costs, and feasibility factors such as availability of analytical methods and treatment technology For lead and copper, MCLGs and MCLs are not used; instead of specifying standards, water treatment is required The process of determining an MCL starts with an evaluation of the adverse effects caused by the chemical in question and the doses needed... levels for the pollutants and provide guidance to states for establishing water quality standards that will achieve the goals of the Act Disposal of dredge or fill materials into receiving bodies of water, including wetlands, is controlled under a separate type of permit program Authorized by Section 404 of the Act, the U.S Army Corps of Engineers administers this program subject to and using environmental... fundamental concepts of the unit operations and unit processes used in the treatment of water and wastewater The authors hope to enlighten engineers and other professionals, who are engaged in water and wastewater treatment practice, with the ability to © 2003 by A P Sincero and G A Sincero TX249_Frame_Intro Page 24 Friday, June 14, 2002 1:45 PM 24 Physical–Chemical Treatment of Water and Wastewater answer... Quarantine Act of 1893, drinking water standards were not legally binding until the passage of the Safe Drinking Water Act of 1974 As shown in Table 5, the Act was amended several times, the last being 1996 HIGHLIGHTS OF THE SAFE DRINKING WATER ACT The most important of the safe drinking water acts are the Safe Drinking Water Act of 1974, the Safe Drinking Water Act Amendments of 1986, and the Safe Drinking... information on the presence of suspicious but still unregulated substances If a violation of the standard occurs, the notifications must contain information about the health effects of the contaminants in question 2 Establishment of programs to train and certify competent water treatment plant operators 3 Establishment of key drinking water standards for Cryptosporidium, certain carcinogens, and other contaminants... government sets the agenda and standards for pollution abatement, while states carry out day-to-day activities of implementation and enforcement (Section 510) Delegation agreements are signed between the governor of a state and the EPA SAFE DRINKING WATER ACT Refer to Table 1 The codification of the Safe Drinking Water Act is found in Title 42, “The Public Health and Welfare.” The chapters of this title range... of the use of the common cup on carriers of interstate commerce such as trains The first act of Congress that had national importance was the Safe Drinking Water Act (SDWA) of 1974 But before this enactment was made, several revisions of the drinking water standards were made in 1914, 1925, 1942, 1946, and 1962.* The following treatment traces the history of the gradually increasing trend of the drinking... forests, construction sites, and urban areas It is this type of pollution that was the cause of a Pfiesteria piscicida outbreak in August 1997 in the Chicamacomico River on the Eastern Shore of Maryland This is a microorganism that releases toxic substances and is widely believed to be responsible for major fish kills and diseases in several mid-Atlantic states As the rain runs off, it picks up pollutant... limit for the total bacterial plate count of 100 organisms/mL and stipulated that not more than one of five 10-cc portions of each sample examined could contain B coli (now called Escherichia coli) The standards were legally binding only on water supplies used by interstate carriers By 1925, the technology of filtration and chlorination was already established, and large cities encountered little difficulty . Sec. 30 5 131 6 National standards of performance, Sec. 30 6 131 7 Toxic and pretreatment effluent standards, Sec. 30 7 131 8 Records and reports, inspections, Sec. 30 8 131 9 Enforcement, Sec. 30 9 132 0. 30 1 131 2 Water quality-related effluent limitations, Sec. 30 2 131 3 Water quality standards and implementation plans, Sec. 30 3 131 4 Information and guidelines, Sec. 30 4 131 5 State reports on water. Characteristics of Water and Wastewater, covers the chapters on quantity and constituent physical and chemical characteristics of water and wastewater. Part II, Unit Operations of Water and Wastewater