reduction in bulk is more important than residual weight when the effect of incineration on the life of a sanitary landfill site is assessed. Tins and bottles, which come through the incineration process largely unchanged, make up a large proportion of the combustible weight and bulk of domestic refuse. If these items were segregated by the householder they could be hauled directly to a landfill site and thereby effect a considerable saving in incineration cost and the cost of residue hauling. However, the housewife finds the practice of segregating solid wastes into separate refuse containers (for example, garbage, combustible refuse and incombustible refuse) onerous and objects very vigorously to such a system. Therefore, the usual practice is to collect mixed refuse and haul the small incombustible items to the dump after they have passed through the incinerator.

Incineration, including burial of the residues, is a relatively expensive disposal method and costs about $5 per ton, as compared to $1 or $2 per ton for sanitary landfilling without incineration when conveniently located large tracts of cheap waste land are available for this purpose. When remote landfill sites must be utilized, transportation costs become an important fraction of the total disposal cost, and transfer of loads from 5-ton or 8-ton packer pickup trucks to 20-ton trailer trucks at intown locations becomes an economical procedure. The experience of Los Angeles shows that transfer operations increase handling costs by $1.25 per ton of refuse. Haulage costs are $12 per hour for an 8-ton truck ($1.50 per ton per hour) and $15 per hour for a 20ton trailer load ($0.75 per ton per hour).* Operating time has been found to be a more reliable guide to costs than the mileage covered, for per mile costs fluctuate widely, depending on local terrain and traffic conditions.

The small percentage of combustion products emitted to the atmosphere from waste incineration that is not carbon dioxide or water vapor consists of ' particulate matter (soot, smoke and gas-entrained solid residues), organic gases (hydrocarbons or aldehydes) and inorganic gases (sulfur dioxide, hydrogen chloride or oxides of nitrogen). These are all recognized as air pollutants. Under ideal operating conditions, a modern high-temperature municipalwaste incinerator totally destroys all organic matter, and the emissions that are of special interest because of their effect on the air environment will be inorganic - principally, particles of solid residue, oxides of sulfur and nitrogen and hydrogen chloride.

All particulate emissions, including smoke, can be eliminated or greatly reduced, even from old incinerators, by the use of dust collectors between the burning units and the discharge stack. Most incinerator dust collectors in current use are either dry cyclones or simple washers. Neither of these devices is capable of removing particles less than 10 H in diameter from the flue gases at high efficiency, and neither is in any nner effective for smoke

and soot. Washers have the added disadvantage of cooling the Aue gases and greatly increasing their density by the addition of water vapor so that they lose their buoyancy when released to the atmosphere and fail to become dispersed and diluted as they do when released in a hot, dry state. High-energy scrubbers, electrostatic precipitators and industrial cleanable cloth filters are the only kinds of collecting equipment capable of reducing particle emissions from incinerators to a low level consistant with modern concepts of acceptable control of air pollution. Of the 3, industrial cloth filters are preferred because they are capable of cleaning the fue gases to the point where no visible emission occurs (greater than 99.9 per cent efficiency), and the cost is no greater than for electrostatic precipitation or high energy scrubbing. At present no municipal incinerator in the United States is equipped with any of these devices except for 1 or 2 small-scale pilot test units. In Germany electrostatic precipitators are used on combination coal-burning and refuse-burning municipal central-station steam plants, but they would have been required, in any case, for burning coal.

The equipment and installation cost of first-class Hy-ash collection equipment for an incinerator suitable for a city of 100,000 to 200,000 population is presently about $500,000. When amortized over the life of the incinerator (twenty or more years) this is just a few pennies added to the tax rate. Therefore, it is difficult to understand why affluent suburban communities are eager to build multimillion dollar, campus-type schools containing swimming pools and other amenities of modern "education" while remaining content to build new incinerators that have been obsolete for twenty years. Unlike education and dogs, waste disposal fails, so far, to arouse aggressive interest among the citizenry, but perhaps a current concern for maintaining the quality of the environment will change this attitude.

Even with the best possible dust collectors to remove all incineration fly ash and complete de struction of all organic matter by high-temperature combustion, contamination of the air may still occur from inorganic gaseous compounds. Oxides of sulfur are formed from the buming of sulfur-containing substances such as protein in food wastes and vulcanized rubber. Most of the sulfur will be in the form of sulfur dioxide, but a small percentage will be converted to sulfur trioxide, and this fraction combines with water vapor in the flue gases to form submicron-sized sulfuric acid mist droplets. Hydro gen chloride is formed during the burning of chlorine-containing synthetic plastics, principally polyvinyl chlorides. The occurrence of hydrogen chloride is increasing with the greater use of plastic materials of all kinds but is not yet thought to be a serious problem of air pollution. Oxides of nitrogen. principally' nitric oxide and nitrogen dioxide, are formed by the fixation of nitrogen from the air in the high-temperature combustion


Hydrogen chloride and sulfur dioxide can be utilization of heat produced in incinerators for muscrabbed from the flue gases with water and chem- nicipal purposes will continue but there appears to al solutions, but this may produce water-pollution be little interest on the part of United States utility problems unless proper provisions are made for the companies in utilizing this form of fuel. There are treatment and disposal of the waste waters. In ad- many technical reasons why this attitude is unlikely dition, the cooling of the flue gases interferes with to change in the foreseeable future. effective atmospheric dispersion. No satisfactory Composting. The practice of solid waste comprocess is available for the removal of nitrogen ox- posting is well developed in certain European Kthes from the hot, dilute incinerator stack gases, and countries, especially in Holland, Germany and atmospheric dilution and dispersal are the only Switzerland. The microbiologic degradation of ormeans now available to prevent the buildup of ex- ganic substances before return to the soil is a well cessive concentrations in the vicinity of the ground. established agricultural process, and when animal Because higher flame temperatures favor the fixation manure is composted with plant refuse, the product of larger amounts of nitrogen, high-temperature has fertilizer value and contains valuable soil conmodem incinerators form more of these compounds. ditioners. Municipal refuse collections in the United In most communities emissions of these inorganic States, composed largely of paper and lacking the gases from municipal incinerators are not regarded rapidly degradable organic component lost to the * a serious problem when they constitute the sole garbage grinder, contain little compostable matter. ao contaminants from these operations and when Consequently, compost made from United States they are emitted at high temperature from tall refuse collections contains virtually no fertilizer stacks

value, and its only uses are for ground cover and There has been considerable interest in the soil conditioner for heavy soils. It has about the United States in 2 European practices: extracting same properties as peat moss. American farmers useful heat from the burning of refuse; and com- have shown no interest in this product, for it is posting of solid wastes.

difficult to apply to fields by automatic machinery Heat recotery The heat content of typical Ameri- and the cost of spreading or working it into the soil on municipal refuse collections is about 5000 Brit- exceeds the benefits that may be obtained. Although ish thermal units (B.T.U.) per pound. When it is several experimental composting plants have operrealized that coals of various grades contain 12,000 ated for brief periods in the United States, they Do 14.000 BT.U. per pound, it is apparent that, in have been uniformly unsuccessful in disposing of the negregate, municipal refuse, composed largely of their product to farmers. It has been proposed that paper products, is a substantial fuel resource. In processors use the fiber for a carrier and diluent of Egrupe coal and oil have been relatively expensive highly concentrated chemical fertilizers, but it does u compared to their cost in the United States, and not seem that that the market for this product (to be this has made recovery of the fuel value in refuse used on lawns and gardens) will support more than cure attractive to the European countries. Also, the a few composting plants. Large-scale utilization of extra manpower required to burn trash has been composted waste would require acceptance by less of a burden in the lower-wage European econ- large-scale farmers, who are generally to be found say In addition, most of the European power- quite remote from the urban centers where the enerating stations that make steam from refuse are waste originates. Perhaps it could be managed if

una ipally owned, and this seems to make the each householder were willing to accept a bag of construction of combined conventional fuel and composted waste in exchange for his weekly refuse terba se-buming central stations more attractive than accumulation. w the United States, where it is more usual for European farmers are also not very enthusiastic power-generating stations to be operated by private about compost from municipal refuse, but some utility companies or by regional governmental au- have been persuaded to accept it when the price is thorities that have no responsibility for refuse col- not much in excess of the cost of transporting it lection and disposal. There are exceptions, however. from the composting plant and the fertilizer value of The Boston Municipal Incinerator, completed a few the product has been raised by the addition of sewyear ago, produces steam for the adjacent Boston age sludge to the raw refuse. The heat generated by Cây Hospital. Although the incinerator must burn the microbiologic activity of composting is sufficient substantial quantities of supplementary fuel to meet to destroy disease-producing bacteria in the sludge te hospital's total requirements (in part, because after a few days, and the mixture is safe to put back the heat-release rate of the refuse has not been as on the soil after a few months of aging. Many Eurogreat a was estimated originally) some of the heat

peans see composting of municipal refuse primarily value to the refuse is being recovered. Many United as a means of disposing of sewage sludge, presently States incinerators utilize heat in the flue gases to a grave problem in central Europe. Many advocates prwide space heating and hot water for the incin- of composting in the United States, including Tutor plant, and a new incinerator on Long Island, manufacturers of composting machinery, have tended New York, is equipped to use waste heat to desali- to stress financial gains from selling the end product. mate sea water by distillation. It is likely that the This is probably a mistake because the income

[ocr errors]

from selling composted refuse is always likely development. One, utilizing an iron-melting cupola,
to be far short of covering the costs of manufacture. or blast furnace, reduces the residue from all man-
However, this approach to composting is probably ner of wastes to a glass-like slag that may be broken
unfair, for other refuse-disposal methods are not up and used for clean fill in road building or as an
required to pay their own way. It should be enough if aggregate for cement. The ability to handle wastes
the net cost of composting, including sales, is no that are ordinarily classed as incombustible and the
greater than the cost of other acceptable methods. compactness of the residue are noteworthy, but the
Although all previous composting plants in the need to purchase supplementary fuel (coke) to melt
United States have proved unsuccessful for tech- iron, clay, sand and similar refractory materials may
nical and financial reasons, the new Office of Sol- lead to excessive costs. In addition, severe fue-gas
id Wastes is preparing to support operational dem- cleaning problems are created by the blast of hot air
onstrations of the leading composting processes over that rises when the falling refuse is fed into the top
a period of several years to resolve, once and for all, of the furnace. Methods for cleaning the stack dis-
whether this is a reasonable refuse-disposal method charges to a satisfactory sanitary standard are avail-
in the United States.

able commercially, but the cost will be high.

Other projects currently supported by the Office Although disposal creates most of the solid-waste
of Solid Wastes include research on incinerator problems collection and transportation of refuse to a
ships at Harvard School of Public Health. Under disposal site represents up to 80 per cent of the
this plan waste collections would be transported to total system cost. It has been noted that "it costs
dockside and transferred to an ocean-going vessel. more to dispose of the New York Sunday Times
When loaded, the vessel would put to sea, burn the than it does a subscriber to buy it."1" Therefore, if
wastes and discharge the residue into deep holes in substantial economies of operation are to be
the ocean floor. Studies are under way to determine achieved, they must be looked for in this sector.
the biologic effects of incinerator residue on marine The widespread use of large packer-type trucks has
species ranging from phytoplankton and lobster greatly increased the quantity of refuse that can be
larvas to founders and clams, Acute and chronic collected between trips to the disposal facility. The
toxicity tests over a period of a year have shown no use of garbage grinders by entire communities
detrimental effects from well incinerated residue at makes it possible to reduce pickups from twice to
concentrations up to two or three times those likely once a week, or even once in two weeks, thereby
to be produced locally during full-scale ship opera- effecting substantial savings in collection costs. This
tions. Meteorologic measurements and analyses are practice increases processing costs at sewage-treat-
under way over offshore waters to locate ideal bum- ment plants, but the net savings will be substantial
ing sites that will avoid the movement of stack dis- Plans for the future include development of mo-
charges to the shore under all weather conditions, bile incinerators that can travel the streets and com
Systems analysis and high-speed computational ma- bine the collection and disposal function into one
chines are being employed to devise economical operation. Conveniently located city gas may be
methods of moving wastes to the water front, and used to assure complete combustion of the refuse.
engineering studies are being conducted to develop even during wet weather; water is available to
incineration and material-handling equipment espe- scrub the particles and soluble gases from the fue
cially adapted for ship use. Preliminary cost analy. gases, and the residues can be dumped into the
ses indicate that this method of waste handling city's sewage system for disposal at the treatment
compares favorably with land-based incineration. plant. Also under consideration are powerful grinders
Convenient dumping grounds (that is, holes in the and modified water-carriage systems that will be
ocean floor) located offshore of coastal cities, and capable of reducing refuse as well as garbage to a
already approved by the United States Coast Guard pulp suitable for transport to a central treatment
and Army Engineers and shown on current marine facility. Ultimately, it may be possible to eliminate
charts, are adequate for handling the residue from completely the use of glass bottles and metal cans
ship incinerators for a hundred or more years. It ap- so that all but a few large objects may be handled
pears practical, therefore, to utilize the vast assimi- in household grinders. Development of these and
lative capacity of ocean waters and the ocean at- other new methods of waste collection are being
mosphere to solve a troublesome urban problem. stimulated and assisted by the Office of Solid Wastes.
Studies show that this can be done without pollut- Junk automobiles present a special problem of
ing the environment, decreasing the recreational use solid-waste disposal for municipalities. New York
of the waters or interfering with commercial and City alone picks up from the streets about 25,000
sport fishing. Other disposal methods presently in abandoned cars per year, and other large metropol
the development stage that utilize the ocean include itan areas have similar experiences. Approximately
compression packaging of wastes and disposal of the 6,000,000 cars were scrapped in 1965. Some of
sealed packages in ocean deeps.

these were salvaged, and some joined the 25,000.-
Many new incineration processes are also under 000 to 40,000,000 already stored in dumps.* Each

automobile in the United States contains about 142
bons of metals, principally iron and steel. The cop-
per radiator, lead battery, cast-iron motor block and
some other special parts are easily removed and
find a ready market. The steel body shell has little
value to steel makers, however, until it is separated
from glass, upholstery, rubber and other nonferrous
materials that make up the usual automobile body.
For many years, it was customary in junk yards to
dram the gasoline from the junked car, pour it in-
sede the body and ignite it. The resulting fire con-
sumed the upholstery, shattered the windows and
therwise removed sufficient non ferrous materials to
make the product clean enough to be acceptable to
steel manufacturers. These fires produced enormous
clouds of black, sooty smoke and were severe local
air-pollution nuisances. Consequently, open burning
of automobiles is prohibited in most urban areas,
and specially designed incinerators, continuous and
batch type, with gas-fired afterburners and tall
stacks were developed for this purpose. These
proved to be satisfactory from the air-pollution-con-
trol standpoint but were costly to operate because of
fuel requirements and low production rate. The
increase in processing cost caused by more stringent
air-pollution control regulations, combined with a
reduction in demand (and price) for steel scrap be-
cause of technologic changes in steel-making meth-
ods, resulted in the buildup of large inventories in
jual car yards

A newer way of handling stripped automobile
body shells (called the Proler process) is to place
them in giant hammer mills and reduce them to
mull pieces of steel, cloth, rubber and so forth that
can be separated magnetically. The product is clean
steel scrap in the form of fist-sized fragments that
be easily handled for loading and unloading, pack
well for economical shipment and melt easily in the
steel fumace. The nonsteel residue is buried. A
sangle full-scale plant of this kind can handle 1000
body shells per day. One, soon to be operational in
the Boston area, will be capable of handling all the
punked cars in New England, and there appears to
be a profitable market for all the steel scrap that can
be produced by this process.

Morrisome solid-waste problems also exist outside
metropolitas areas. These include mining refuse of

all kinds and the severe disturbances to ground and
water caused by large-scale strip mining. Agricul-
tural waste disposal problems are countrywide,
ranging from long standing and severe pollution of
Long Island's inland bays by duck-raising farms and
duck-packing plants to enormous accumulations of
manure in California's cattle-raising western valleys.
However, these special problems are outside the
scope of urban solid-waste management.

An urgent need for better methods of solid-waste
management in all sectors of the economy, com-
bined with the powerful stimulus provided by Solid
Waste Act funds, is opening up a period of active
development and experimentation in solid-waște
technology that will result in the rapid introduction
of the modern systems now needed. The need will
be even more urgent by the end of the century. A
most hopeful sign is the current interest among
universities and research institutions in tackling
solid-waste problems as an interdisciplinary study
involving the special skills of urban planners, so-
ciologists and economists, with those of sanitary
engineers, public health administrators and public-
works specialists.


1. American Public Works Assixiation, Committee on Solid Wastes

Refuse Collection Practice. Third edition. Chicago: Public Admin-

istration Service. 1966. P. 27
2. Wegman, L. S. Cated in Refuse Collertion Practice.'
3. (hlbertson, W. E. Solid wastes: worsening urban problem.

Presented on September 12, 1966. before Public Works Congress

sponsored by American Public Works Assoxiation, Chicago, Illinois.
4. First, M. W., Viles, F. J. Jr., and Levin, S. Control of toxic and ex-

plosive hazards in buildings crected on landfills, Pub. Health Rep.

81:419, 1966
5. President's Science Advisory Committee, Environmental Polution

Panel. Restoring the Quality of Our Entrronment. The White House,

November, 1965. P. 17.
6. Committee on Science and Astronautics Subcommittee on

Science, Research, and Development, înted States House of Re-
presentatives, 89th Congress, 2nd Session. Environmental Pollution. A
challenge to science and technology. Washington, DC (overnment

Printing Office, 1966. P. 44
7. National Academy of Sciences -- National Research Council,

Committee on Pollution. Waste Management and Control: A report to the
Federal Council for Science and Technology. Washington, D.C.. Na-

tional Research Council, 1966. (Pub. No 1400.) P. 32.
8. American Public Works Association. Munucipal Refuse Disposal.

Second edition. Chicago. Public Administration Service, 1966 P. 42.
9. Bowerman, R. F., and Dair. F. R. Supplemental refuse transpor.

tation for incineration. Presented at 1966 National Incinerator Con-
ference, American Society of Mechanical Engineers, New York City.

New York, May 2, 1966.
10. Time 88 (21):57. November 18, 1966.

Copyright, 1966, by the Massachusetts Medical Society

Printed in the U. S. A.

Senator MUSKIE. The next witness is John C. Collins, director, division of environmental health and chief sanitary engineer for the Massachusetts Department of Public Health. It is a pleasure to welcome you, sir.


Mr. COLLINS. Delighted to be here, Senator.
Senator MUSKIE. Is this part of the Collins dynasty?

Mr. COLLINS. No; but I am sure if we reach far enough back, there is a relation. [Laughter.]

Senator MUSKIE. Well, I associate Boston with family dynasties for some reason. [Laughter.]

Mr. Collins. My dynasty is from north of Boston.
Senator MUSKIE. It is a pleasure to have you, sir.
Mr. COLLINS. Do you wish me to proceed?
Senator MUSKIE. Yes, please.

Mr. Collins. I have a prepared statement here and, of course, I would be delighted, after, to answer any questions which I may be able to.

I would like to point out that my remarks will be directed primarily to Massachusetts and the problems that we have here in Massachusetts.


The Massachusetts Department of Public Health has been greatly concerned for a number of years with the solid waste problem. I imply by that that we have had a great deal of involvement over the years. The department places a very high priority on the need for recognition of and resolution of this so-called "third pollution.” The present insanitary management of solid waste disposal creates not only sources of environmental pollution and nuisance conditions but provides a continuing potential for disease transmission.

Within the State the activities of the department primarily center around two pieces of legislation. One is a permissive piece of legislation allowing for regional approaches, development of regional facilities by municipalities. It is interesting to point out here that this was enacted in 1965, but as of this date no regional disposal facility has been established.

The other piece of legislation provides more or less a concurrent authority. It provides for an assignment of a site for a disposal facility by the local board of health, but allows the department of public health to hold public hearings in the event of problems with the operation of the facility.

I think it is particularly interesting that over the last few years the department has found it necessary to modify the assignment in many communities and require the elimination of the open-burning dumps and require the operation of the disposal site as a sanitary landfill.

One hearing held under the provisions of this legislation concerned a privately owned and operated commercial solid waste disposal facility serving some 15 communities, thousands of business establishments, institutions and similar agencies and numerous private-commercial refuse collectors throughout the Metropolitan Boston area.

« ForrigeFortsett »