Under certain conditions, disposal of garbage 
through the sewage treatment plant may be advanta- 
geous to its operation by increasing gas production 
(Johnson, Gerald, 1955). (29) However, garbage 
grinding, either at homes on a large scale or at a 
central grinding station, requires that certain of the 
sewage treatment plant facilities (e.g., digestion 
and drying) be of greater capacity than would ordi- 
narily be required. When garbage from the home 
grinder is conveyed to a private sewage system, 
the capacity of the septic tank needs to be in- 
creased by about 50 percent. 
Composting 
Garbage composting is a biological process in 
which the material is usually shredded or ground 
and processed under anaerobic and/or aerobic 
conditions. Old World methods make use of anaero- 
bic processes initially, followed by aerobic stages. 
The completely aerobic process, generally recog- 
nized as superior, generates temperatures of ap- 
proximately 160° F. This heat accelerates fermen- 
tation, reduces dangers from pathogenic organisms 
and makes the mass unattractive to vermin. Control 
of moisture content, oxygen, pH, and temperature is 
important to the efficiency of the process. 
“In the modern sense, composting might be 
defined as a process in which under suitable envi- 
ronmental conditions facultative aerobic micro- 
organisms, principally thermophilic, break down 
organic matter to a fairly stable humus” (Reclama- 
tion of Municipal Refuse by Composting, 1953). (51) 
Composting has been in use in Europe and Asia 
for many years but in the United States its use has 
been largely experimental. A number of projects 
have been started on a commercial scale but for 
numerous reasons most have been discontinued. 
In the past few years renewed interest in this 
method of refuse disposal has resulted in increased 
research on the subject. However, further study and 
experimentation are necessary to determine the 
most efficient and practical methods for composting 
municipal refuse without creating conditions favor- 
able to flies and rats and to determine the economic 
feasibility of producing compost for use as a soil 
builder. 
NOTE: Since the Sanitary Landfill and the Inciner- 
ator are two of the more acceptable and satis- 
factory methods of refuse disposal, their planning 
and operation are described here in detail. 
THE SANITARY LANDFILL 
Introduction 
The sanitary landfill is an effective, proven 
method for the permanent disposal of refuse. It has 
been used in this country since about 1915, but has 
become a major method of disposal only since the 
late 1930’s. 
The sanitary landfill method can be used in any 
community where sufficient suitable land is avail- 
able. It is especially suited for cities of less than 
100,000 population because sufficient land is more 
likely to be available in these areas. Basically, 
this method of disposal consists of the following 
four steps: 
1. Depositing the refuse in a planned, con- 
trolled manner. 
2. Spreading and compacting it in thin layers to 
reduce its volume. 
3. Covering the material with a layer of earth. 
4. Compacting the earth cover. 
Preliminary Considerations 
Site Selection. The choice of a disposal site 
should be governed largely by the proximity to the 
source of refuse and by such factors as the avail- 
ability of suitable land, access roads, and bridges. 
This consideration usually determines whether or 
not the sanitary landfill method of refuse disposal 
can be used economically. 
1. Land must be available at reasonable cost 
and in sufficient acreage. 
2. It must be located so that hauling distances 
are not too great. It may be located close to 
residential areas. 
3. The most desirable landfill soils are sandy 
loams. However, where ideal soils are not 
available, operational procedures may be ad- 
justed to local conditions. When suitability 
of the soil is in question, samples should be 
collected by borings and should be analyzed 
to determine the composition. Locations hav- 
ing solid rock formations close to the surface 
or with large boulders should be avoided. 
4. Access roads and bridges must be capable of 
supporting loaded trucks. Stabilized or hard 
surface roads are especially important during 
wet weather operations. 
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