Solid Waste 2017 Flashcards
Define refuse
mixture of organic and inorganic materials
no such thing as “trash”
Define rubbish
inorganic material component of refuse
does not break down by decomposition
ex: bottles, cans
Define garbage
organic waste material component of refuse
readily breaks down
makes up 50% of refuse
What are the three types of landills?
Trench method
Area method
Valley or Ravine method
What is the Trench method?
Commonly used in level terrain
Large earth moving equipment digs trenches through excavation
solid waste filled into trench
backfilled and compacted
aka “Cut and Fill” method
What is the Area method?
uses side of hill or sloped area
refuse dumped and covered with dirt
most common method in the US
continued until entire slope is leveled
What is the Valley or Ravine method?
Landfill located in area with large depressions or slopes such as a valley or ravine
refuse dumped, filled with dirt, and compacted
once leveled or exhausted, can be used as golf course or parks
commonly used by large cities
What are the three classifications of landfills?
Class 1 - hazardous materials accepted for disposal
Class 2 - low level hazardous materials accepted for disposal
Class 3 - no hazardous materials accepted
What type of soil is used in landfills?
sandy loam is soil choice
What are the rules on landfill cover?
Minimum daily cover is 6”
compacted to prevent fly larvae emergence
min final cover is 24”
What are the slop rules for landfill cells?
ideal slope 1:2, 50% 26.3 degree angle
final closing slope is 1:3, 33%, 18.3 degree angle
What type of decomposition gases do you find in a landfill and where do they come from?
methane
CO2
Hydrogen sulfide
anaerobic decomposition
What are the states of a landfill in regards to bacteria?
aerobic state is between 4-60 days
anaerobic state after 60 days
What is leachate?
Any liquid waste that comes out of a landfill
What are windrows?
Rows of compost piles positioned to allow air to flow through promoting aerobic decomposition
What is incineration?
burning of waste products
What are the rules of smokeless incinceration?
temp should be maintained at 1500-1800F
What are the rules for hospitals with incineration?
incineration of bio-hazards can be set to ideal temp of 1500F
after proper incineration, expect 25% solid residual ash which can be used to enrich soil
What are the landfill setback requirements?
must be 200’ min from lakes/streams
must be 500’ from human habitation (communities)
citing landfill sites should be for duration of at least 20/40 years
What are the classes of soil in order of most to least absorptive? (6)
sand - most absorptive
sandy loam
loam
silt loam
clay loam
clay
What would red/brown soil result in in regards to absorption?
typically good water absorption
What would blue/black soil result in in regard to absorption?
typically bad perc rates, slow water absorption
What would mottled soil result in in regards to soil absorption?
not very good soil for water absorption
