Page 398 - Materials Chemistry, Second Edition

CAT3525_C10.qxd 1/31/2005 12:00 PM Page 369
The Sanitary Landfill 369
EXCEL EXERCISE

GROUNDWATER QUALITY AT A MIDWEST LANDFILL
FILE NAME: LANDFILL.XLS

The Situation
In the 1970s, a gravel pit located in the Midwest United States was converted into a landfill opera-
tion. At that time, no state regulations existed which would prohibit such a conversion. Therefore,
although the land was completely unsuitable for such use, landfilling began. Landfill operation was
relatively small (30 acres), and in 1977, the owners expanded operations to a total of 55 ha. In 1979
the state began to regulate landfill activities and, where the site did not meet the instituted state reg-
ulations, it was permitted to continue operations under a “grandfather clause.”
The data for this exercise can be located at www.crcpress.com/e_products/downloads/
download.asp?cat_no=3525
In 1982 a new operator purchased the facility. During the first year of operations the new owner
had problems with leachate, runoff, and trash released from the site. The company decided to insti-
tute sound landfill management practices. They also began to buy land surrounding the original site.
Since that time, the operation of the landfill improved, meeting the requirements of the state regu-
latory agency. Trees were planted to improve the aesthetics of the operation. The perimeter of the
facility is patrolled and the company conducts business in the community. The landfill currently
employs over 30 people from the community.
In 1995 the owners began petitioning the Area Planning Commission to expand the land that
was permitted for landfill operation. The land for which they are seeking zoning is an additional
100 acres.
Practical Issues of the Landfill

1. Contamination from the current landfill has the potential to contaminate drinking water,
not only of the immediate community, but also of other nearby communities. This poten-
tial results from two conditions:
(a)The landfill is sited on a drainage divide. The drainage to the south of the landfill
enters one river basin, and the drainage to the north enters a second river basin.
Therefore, any contamination from the landfill will pollute two water systems, which
pass through as many as 18 counties.
(b)The subsurface of the land in question contains at least three aquifers. Test wells
drilled show that water occurs at depths of 20 to 25 ft. In addition, a moraine, which
lies beneath the landfill, conducts underground water away from the landfill in several
directions. Data for a range of inorganic contaminants in test wells appears in the
spreadsheet, “GW_LF”, Sheet 1.
2. Limited tests of water taken from wells at the perimeter of the landfill have shown con-
tamination from total organic carbon. The presence of certain halogenated organic com-
pounds was also identified. Other volatile organic compounds such as trichloromethane
and dichloroethane were found. These data appear in Sheet 2.
3. The effects of leachate contamination from special waste and other wastes disposed at
the landfill are not presently known. The potential for adverse environmental, health,
safety, and social impacts must be considered.
4. Now that the number of landfills in the state have decreased significantly, it is probable
that this facility will handle even greater amounts of wastes in the coming decade.