Page 274 - Materials Chemistry, Second Edition

CAT3525_C08.qxd 1/29/2005 10:03 AM Page 245
Composting MSW 245
EXCEL EXERCISE

SOIL AND GROUNDWATER QUALITY AT A COMPOSTING FACILITY
FILE NAMES: COMPOST_SOIL.XLS

COMPOST_GW.XLS
The Situation
In 1992, a municipality in the eastern United States installed a MSW and food waste composting
facility. A local farmer contracts some of his property for the facility. Surficial materials are silt
loam or silty clay loam. At a depth of approximately 40 cm (16 in.) below ground surface, loam is
the predominant texture, and beyond this horizon there are occasional lenses of coarse sand and
gravel. Three small streams occur within 0.5 to 3 mi of the facility. There were no siting regulations
at the time of the installation, and therefore no concrete pad was installed during construction.
Rainfall ranges from 42 to 48 in. per year.
The data for this exercise can be located at www.crcpress.com/e_products/downloads/
download.asp?cat_no=3525
MSW arrives at the compost site from two municipalities (‘MSW1’ and ‘MSW2’); both have
previously processed their wastes via shredding and magnetic separation. A third facility tips sig-
nificant quantities of vegetable processing wastes including plant waste and washings. These three
wastes are composted separately for a research project (below).
MSW1 contained large proportions of yard waste whereas MSW2 did not. Additionally, MSW2
contained a significantly higher proportion of inerts such as glass, stone, and some metals.
Research plots were established on the property (see map) by a university group to test the
effects of the composts (if any) on soil and groundwater properties. Maize, soybeans, and pasture
hay were grown on the plots. Plot setups are shown below.

The materials applied at the East Fork site were as follows:

Material Plot Designation
MSW1 1A, 1B, 1C
MSW2 2A, 2B, 2C

Inorganic fertilizer 3A, 3B, 3C
Food processing waste 4A, 4B
No treatments Control

For the Powder Creek site:

Material Plot Designation
MSW1 5A, 5B, 5C
MSW2 6A, 6B, 6C

Inorganic fertilizer 7A, 7B, 7C
Food processing waste 8A, 8B
No treatments Control