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on the grounded cylinders by the appropriate adjustment of the rate of gas flow. In the second chamber-consisting of alternately charged, loosely packed and parallel plates-satisfactory precipitation can be attained by applying a lower potential than that required in the charging chamber, since there is no need for a corona discharge.

The corona discharge is usually produced by making the center wire the cathode, because precipitation efficiency is greater under such an operating condition. Less ozone is produced, however, by reversing the polarity, and a positively charged wire is employed in the cleaning of air if the presence of ozone is objectionable.

The high-voltage direct current is generally produced by either mercury vapor or vacuum tube rectifiers. The power requirements vary from 2-5 kWh per million cubic feet of polluted gas being treated, and the variation will be a function of the quantity, size, and physical properties of the particulates that are being removed.

Figure 15 is a cutaway view of an Opzel plate precipitator, manufactured by Research-Cottrell, Inc.

Effect of precipitators on suspended particulates in an ambient atmosphere. Electrostatic precipitators were installed to supplement mechanical ash collectors at one of the TVA plants after a special investigation was conducted to determine the relationships between SO2 concentrations and suspended particulates in the vicinity of the plant where maximum ground level concentrations of stack emissions occurred. Data were analyzed with the results shown in Fig. 16. From the two derived equations indicated on the graph, TVA estimated that the electrostatic precipitators reduced the suspended particulates by 85 percent in the ambient atmosphere at ground level during those periods when SO, was present.

The TVA believes that an additional-although unproved-possible benefit from the electrostatic precipitators is a reduction in the maximum ground level SO, concentrations in the vicinity of steam plant emissions. This is predicated on data indicating that the maximum recorded SO, concentration during the four years of precipitator operation is about 25 percent less than that recorded prior to precipitator operation.

Power plant pollution potential under air stagnation (temperature inversion) conditions. Air pollution control plans developed for the Kingston plant, until recently the largest steam-electric station in the TVA system, gave special attention to the SO, problem associated with periods of atmospheric stagnation.

This plant is located on the floor of an Appalachian valley. The local terrain has parallel ridge features that vary from 400 to 1000 feet above the plant grade level.

During the period from November 9-11, 1964, a temperature inversion occurred in the Kingston plant area. The U.S. Weather Bureau, by prearrangement, alerted the TVA beforehand, and précautionary air pollution control measures and monitoring were initiated.

Sulfur dioxide autometers were checked at regular intervals, and mobile sampling was conducted during the 3-day period by specially equipped helicopters and cars. The frequency and concentration of SO, recorded at ground level were no higher than during normal atmospheric conditions. The absence of an SO, buildup was attributed to penetration of the low-level inversion by the hot, high-velocity stack gases and dispersion of the smoke plume from the area by light and steady winds. Figure 17 indicates the time and temperature conditions aloft,

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and the plume elevation during a timed sequence on November 10.

From the data obtained during this monitoring, it is possible that air pollution predictions should consider power plants as a special case for which normal meteorological criteria may not apply.

The other half of the foggy, smoggy brew

If the witch's brew concocted in the smokestacks of American industry seems appalling, cheer up; for it is only half of the dirty story. Most of the other half may be found in Fig. 18. The U.S. Public Health Service estimates that the 88 million motor vehicles on the nation's highways belch into the atmosphere about 350 000 tons of carbon monoxide, volatile hydrocarbons, and nitrogen dioxide daily. The automobile population in the United States is increasing at more than double the rate of the human population! Urban traffic jams are providing civilization with one of its most diabolical methods of multiplying the problems of air pollution; and, unless

something is done to correct this man-made plague, our metropolises will soon become obsolete and deadly places for human habitation.

Pollution control devices for cars. In addition to assuring more complete combustion of hydrocarbon fuels in internal combustion engines by simple carburetor and ignition system adjustments, there are two basic devices that can effectively reduce the amount of air contaminants released from motor vehicle exhausts. For an investment of about $5, crankcase blowby units, which return unburned gases to the combustion chambers, can be installed. Properly maintained blowbys can reduce an automobile's hydrocarbon emission by at least 25 percent. There is also an "afterburner" device, which, when attached to the tailpipe of a motor vehicle, will complete the combustion of carbon monoxide and other unburned gases. When used in conjunction with a crankcase blowby, the afterburner would eliminate the major portion of pollutants now poisoning the air from this source.

It is no secret that the automobile industry has been dragging its feet for a long time in resisting the factory installation of these control accessories. The weight of public opinion, and public officials who have been aroused by the menace of the motor vehicle situation, has forced the hand of the manufacturers. These devices will be required by law for 1966 model cars to be sold in California.

A pollution survey, city by city

The Pittsburgh story. Since the 1940s, a generation of young Pittsburghers has grown up convinced that the sky above them is really blue, ar. 1 not murky gray as they were assured by their parents. And it is possible to put on a white shirt in the morning, wear it all day, and still find it reasonably clean. Housewives, too, are able to hang out a line of wash without having to relaunder it the same day.

Before the 1940s, Pittsburgh was the classic American example of continual air pollution. Since the middle period of the Industrial Revolution, the "Smoky City" blamed its railroads and concentrated industry for its plight. The Pittsburgh Chamber of Commerce appointed its first committee on smoke abatement in 1899, and a smoke control ordinance was passed in 1906. For the next 35 years, the Chamber of Commerce and other civic groups hoped that education in matters of proper fuel combustion and pollution control devices would help to solve the problem. But the results of self-regulation were negligible; the situation deteriorated, and enforced regulation seemed to be the only answer.

The City of Pittsburgh Smoke Control Ordinance was passed in 1941, and more stringent amendments were added in 1943, 1946, and 1951. Dual enforcement by Allegheny County and the city is in effect today.

Under the provisions of the ordinance for smoke and air pollution control, limitations are established on the emission of smoke, fly ash, soot, cinders, toxic or radioactive substances, noxious acids, fumes, oxides, gases, and odors, or any other matter that may create atmospheric pollution. These regulations further stipulate that the home owner should do one of several things:

1. Burn highly volatile bituminous coal by installing a stoker.

2. Burn briquettes or other forms of prepared coal, coke, anthracite, or less volatile bituminous coal. 3. Use gas or oil.

Emissions from furnaces of the steel and allied industries are generally restricted to two parts of solids in every 3000 parts of gas, but these limits can vary somewhat dependent upon the types of furnaces employed.

The installation and repair of furnaces, boilers, and other fuel-burning equipment must be done under a permit issued by the terms of the Rules and Regulations of the Pittsburgh Smoke Control Ordinance. With the exception of installations in private residences, furnaces or other fuel-burning equipment are subject to periodic inspection by the Bureau of Air Pollution Control.

To date, the result has been gratifying. Pittsburgh has an average sootfall of only 30 tons per square mile per month as compared with 60 tons for a similar area and time period in New York.

Chicago-soot, smoke, and steel. The nation's second largest metropolis-population 4 million-is gravely

endangered by both air and water pollution from the Calumet region of neighboring Indiana. The concentration of steel mills at Hammond and Gary, a scant 15 miles from the Chicago loop, belch a continuous barrage of acrid fumes, and the smoke plumes from these emissions are an ever-present facet of the seascape over Lake Michigan. The legal aspects of this situation are complex. As one leading Chicago spokesman put it: "The cities and towns along the lakefront are not doing a good job of pollution control. And Illinois state agencies are unable to cope satisfactorily with the issues since interstate problems are involved." In view of this, the general sentiment among Chicago officials is that the Federal Government should enforce antipollution controls under Congressional authority.

Air pollution control is being handled by a special city agency. In the three years since its formation, this agency has held 2800 hearings, handled 5000 smoke complaints, inspected 50 000 furnaces, and has filed almost 600 suits for the prosecution of chronic violators. There are also 20 rooftop monitoring stations in the city that were established to trap pollutant particulates in the air, and another 35 specially equipped stations measure the dustfall and SO, content.

A three-year Federal grant of $357 000 has assisted Chicago in putting teeth into its enforcement of pollution control. It is hoped that, by 1968, all improper burning of combustible refuse will be banned. This would put the damper on about 30 000 Chicago apartment houses that foul the atmosphere with soot from coal-fired boilers.

Like all major cities, Chicago has its smog—a noxious blend of automobile fumes, industrial pollutants, and soot. The present sootfall is about 43 tons per square mile per month.

Recently, the four major steel producers in the Calumet region agreed to appropriate $50 million over the next seven years for pollution control equipment. It is believed, hopefully, that this equipment will cut the 60 000 tons of pollutants released annually to half that amount by next year.

Chicago has no illusions about quick and easy solutions to its overall pollution problems, but at least the city is doing something about them.

Houston an industrial complex of chemicals and contaminants. Houston, Tex., is probably the fastest growing city in the United States. And concurrent with this phenomenal growth is the tremendous increase in the number of petrochemical plants, oil refineries, paper mills, and other heavy industries that gird the city's perimeter. Although pollutants from coal combustion are no problem here (natural gas is the most common fuel for both industrial and domestic use), the melange of chemical fumes released into the air is causing considerable apprehension. When the wind is from the southeast quadrant, the sickening fumes from "old smoky”– a sulfite process paper mill in suburban Pasadena-are very apparent in downtown Houston.

Carbon monoxide and the nitrogen dioxides, caused primarily by the heavy automobile traffic, are found in the same ranges of concentration as those reported in other large cities.

However, the general feeling in Houston is that the air pollution problem, at least, is under fairly good control. Private industry has shown an inclination to comply with local city ordinances, primarily because it knows that the

"The problem of sulphur pollution has grown (in New York) until now the measured concentrations of sulphur dioxide are higher than in any other major city in which such measurements are taken." -V. G. MacKenzie,

Assistant Surgeon General,
Chief of the Air Pollution Division,
U.S. Public Health Service

city is quite willing to initiate court action to curb flagrant violations.

Los Angeles and New York. Reams of copy have been written over the past 20 years about the lethal smogs, principally caused by the fantastic motor vehicle population and domestic trash burners, in Los Angeles; and any further emphasis on the situation in this West Coast metropolis would seem boring and repetitious to the reader. Suffice to say that, in 1960, California passed a law requiring all new motor vehicles sold in the state to be equipped by the owners with the crankcase and tailpipe devices previously described. State officials estimate that more than 4 million California vehicles are now equipped with these devices and they are removing about 200 000 gallons of unburned gasoline from the atmosphere each day.

The air pollution situation in New York, however, is so far out of gontrol that this writer could be panicked into leaving the city after reviewing his own copy. New York channels most of its air contamination problems into the municipal Department of Air Pollution Control, whose commissioner, Arthur J. Benline, frankly confesses that far too little money is appropriated either by the city or by the Federal Government to do an adequate job. During a recent television interview, Benline summed up the New York situation in two terse sentences: "The air over our city is helping our citizens to shuffle off this planet at a much higher rate than they would ordinarily go. Yet there has not been any overall demand from the public to clean up our dirty air." So, in the meanwhile, the city muddles through, and everyone hopes that, by some miracle, adequate corrective measures will be taken before any future prolonged temperature inversion produces the disaster that many health authorities fear.

The air pollution situation throughout most urban areas in the United States closely parallels the samplings just described in five major cities.

A utility answers its critics

At a recent hearing called by the Special Committee to Investigate Air Pollution (authorized by the New York City Council), the Consolidated Edison Company of New York replied to the Committee's accusation that Con Edison is one of the principal contributors to the air pollution problem. Otto W. Manz, Jr., the company's executive vice president, contended that the utility has done a conscientious job of providing adequate air pollution control equipment and devices in its city generating plants to minimize the emission of contaminants. In outlining future plans on the subject of air pollution con

trol, Manz listed the following activities, presently under way, that will either decentralize electric generation to remote areas or significantly reduce objectionable stack emissions in city-located generating stations:

1. The construction of the Cornwall pumped-storage station, which will produce about 2000 MW of power, and will permit the retirement, or placement on cold standby, of about 750 MW of generating capacity that is presently being supplied by city steam-electric stations.

2. The possible substitution of more natural gas for coal as an alternative fuel for generating purposes.

3. The establishment of firm interconnections, by EHV transmission, with the CONVEX group of New England utilities and with the Pennsylvania-New JerseyMaryland (PJM) complex.

Manz believes that the ultimate answer to the problem of air pollution in metropolitan areas, insofar as power generation is concerned, is the use of nuclear energy. He cited the Indian Point nuclear generating station in suburban Westchester County that has been in operation for almost three years and is a firm and reliable producer of power for the Con Edison system.

The Con Edison spokesman sounded a warning note, however, on the subject of who will eventually pick up the tab for air pollution control measures. To quote from Manz' 8-page prepared statement:

"Our estimate is that on and after October 1, 1969, when the maximum sulfur content in these [coal) fuels will be 2.2 percent by weight, the additional annual cost of the fuels used by Con Edison and which will be passed on to the consumer could be as much as $20 million."

Where do we go from here?

As one public health official bluntly put it: "Perhaps we are worrying about the wrong menace. Our urban civilization stands a much better chance of being suffocated by air pollution than being annihilated by atomic weapons."

From numerous surveys, it is obvious that the sources of air pollution are numerous and complex. There is no single group or interest toward whom we can point an accusing finger as being the sole villain of the drama. Until heavy industry, the utilities, car manufacturers, and the general public become totally aware of the truth about air pollution and the consequences of irresponsibility, the already intolerable situation will become impossible.

Piecemeal solutions are not the answer. A city committee cannot correct a situation-such as in Chicago and to some extent in New York-whose origins are interstate. Total and effective remedial action must be undertaken by joint commissions that represent municipal, state, Federal, and private interests.

Life depends upon the air we breathe.

The author wishes to acknowledge the following picture credits: Fig. 1, N. Y. Journal-American; Figs. 2 through 8, U.S. Public Health Service, Division of Air Pollution; Figs. 9 and 10, Mechanical Engineering magazine; Fig. 13, Research-Cottrell, Inc.; Fig. 18, Los Angeles Times.

REFERENCES

1. Dinman, B. D., Frankenberg, T. T., Gartrell, F. E., Gerber, A., Ireland, R. L., Jones, J. R., Perry, H., and Ripperton, L. A., "Panel discussion of the clean air problem," presented at the American Power Conf., Chicago, Ill., Apr. 27-29, 1965.

2. Frankenberg, T. T., "Sulfur removal: for air pollution control," Mech. Eng, vol. 87, no. 8, pp. 36-41; Aug. 1965.

Solid waste management is an area in which innovative research and development activities are sorely needed. It is possible to put a rough price tag on the desirable level of research and development funding, if the practice of industry is used as a yardstick. Ordinarily industry invests something on the order of 5 percent of its gross income on research and development. These funds are used for basic research, the results of which may have no immediate practical applicability, and for efforts to improve quality of output and reduce costs. A segment of industry involved in an area of rapid technological change or growth may invest as much as 10 percent annually in research and development in order to secure a position in the forefront of technological advancement, and thus to maintain a competitive advantage.

The solid waste management field is somewhat analogous. Solid waste collection, processing, and disposal cost the Nation in excess of $3 billion each year. Since this is a field in which technological innovation is needed and will have to be paid for, it would seem reasonable to assume that an amount equal to 5 to 10 percent of the annual solid waste "business" should be invested in research and development-that is, somewhere between $150 and $300 million a year. În our view, taking into account the public health aspects of the solid waste problem as well as its economic, technological, and public policy ramifications, annual expenditures for solid waste research and development would best be allocated in the following way:

Public health and environmental pollution control, 50 percent;
Solid waste technology improvement, 35 percent;

Public administration, systems analysis, cost-benefit analysis, 15 percent.

A division of funds such as this is, of course, not without some areas of overlap. Technology improvement, for example, would have to take into consideration the public health implications of new, experimental techniques and procedures.

By no means all of the cost of solid waste research and development on this scale should be borne by the Federal Government. State and local governments should be expected to contribute, but industry should assume responsibility for a major share of these costs, particularly in the area of solid waste technology improvement. This assignment of funds should assure rapid progress toward the control of environmental health hazards associated with solid waste generation and disposal.

Question 3: During his testimony, Mr. MacKenzie indicated that there were numerous laws and regulatory codes which inhibited or appeared to inhibit progress or enforcement of pollution abatement action. Please furnish a list of such laws and regulatory codes and the extent to which such laws and codes interfere with pollution abatement and enforcement.

Answer: Mr. MacKenzie's testimony on this point was given in response to a question on whether more rapid progress could be made by spending more money for air pollution abatement. This was Mr. MacKenzie's response: "I think one of the impediments to making more rapid progress than has been indicated in Mr. Cohen's statement relates to the existence and scope of activity of State and local government regulatory control activities. I would like to point out to the

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