e. Operational Data. To determine landfill
operational requirements and associated costs, the
Prior to disposing of solid waste at a new landfill
following information is needed:
facility, samples from monitoring wells will be
(1) Hours of landfill operation.
collected and analyzed in order to obtain baseline
(2) Hours of equipment operation.
data on existing ground-water conditions. Samples
(3) Fuel consumption.
should be collected from all monitoring wells and
(4) Major repairs.
analyzed at least once a year. The analytical
(5) Hours of down time for major repairs.
methods specified in 40 CFR 136 will be followed.
c. Facility and Structures. All enclosed struc-
(6) Labor hours spent on major repairs.
(7) Routine maintenance.
tures at a landfill disposal facility should be
(8) Labor hours spent on routine maintenance.
monitored regularly to detect accumulations of
(9) Cover material used.
explosive gases such as methane. Detection of
(10) Daily weather conditions.
other gases which might pose a safety hazard to
The operational and trench data should be main-
employees and workers should also be considered.
tained in a computerized form, and also recorded
Explosive gases, can be detected with a device
manually in a log book.
called an "explosimeter." Toxic or asphyxiating
gases should be monitored on a regular basis with
d. Perimeter Soil Monitoring. In most cases
a. General. Monitoring is an essential activity in
where landfills are lined and the material used for
establishing, operating, and closing a solid waste
daily cover is relatively porous, gases generated
landfill disposal facility. Where possible, monitoring
within the landfill will not move laterally away from
should be coordinated with State and local air and
the site, and thus perimeter soil monitoring is not
water quality management activities. Landfill
necessary. However, if such soil gas monitoring is
disposal facilities should be monitored as follows
required, the following shall be observed:
for the purposes of determining if and when a
(1) Suitable probes should be installed in the
contingency remedial action plan should be
soil at the property boundary surrounding the
implemented to correct an environmental problem.
landfill to enable detection of gases migrating away
b. Ground-water. A ground-water monitoring
from the facility.
system will be installed at all landfill disposal
(2) Explosive gases should be monitored for
facilities which have the potential for generating
concentrations above the lower explosive limit.
substantial quantities of leachate. In no case shall
(3) Toxic or asphyxiating gases should be
ground-water monitoring wells be installed through
monitored on a regular basis with appropriate
the bottom of the landfill proper since such
installation could create a conduit for the direct