Transcript Environmental Health Issues in Solid Waste Management

Environmental Health Issues
in Solid Waste Management
Alan Eschenroeder, Ph.D. and
Katherine von Stackelberg, S.M.
Harvard School of Public Health
18 November 2002
A Four Step Policy Hierarchy in
Municipal Waste Management
Analyses Compare Landfill with Combustion
Two size scales; Two technology scenarios

Microscale: Local human health impacts
 Macroscale: Global climate change impacts
 Current regulation defines technology level.
 Pollution prevention determines technology level.
Waste Stream for Both Facilities

Source reduction and recycling are constant.
 2000 tpd of MSW stays level through 30 years.
 Both have a post-closure period of 70 years.
Health Risk Methodology
for Both Facilities

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Identify hazards, and characterize emissions.
Assess dose-response relationships.
Assess human exposures through various routes.
Characterize health risks.
Follow EPA protocol for analyzing risk.
Contemporary Landfill Scenarios:
Present Regulation: Subtitle D - “dry tomb”
Pollution Prevention: Leachate recycling - “wet cell”
Contemporary Combustor Scenarios:
Present regulation: Max. Available Control Tech.
Pollution Prevention: Energy Answers System
The risk analysis includes many pathways.
The landfill generates gas for a long time.
How do health risks compare?
landfill versus combustion assuming equal recycling
Most of the landfill risk is in groundwater
Compare climate change impacts

Calculate GHG emissions over a 100 year period
 Model CO2 atmospheric response from IPCC data
 CH4, N2O, and CFC removal follow IPCC kinetics
 Obtain radiative forcing histories for both facilities
Cases Studied in Climate Change Analysis

Case 1: Landfill (LF) with no gas collection;
neither landfill or resource recovery (RR) is
credited for displacing fossil fuel power plants.
 Case 2: LF collects its gas; both LF and RR
receive fossil fuel emission displacement credits.
 Case 3: Identical to Case 1 except both LF and RR
receive biogenic carbon discounts.
 Case 4: Identical to Case 2 except both LF and RR
receive biogenic carbon discounts.
How do IPCC biogenic discounts work?
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Materials of recent biogenic origin are credited by assuming
that the CO2 emitted cancels out that taken up in the plant of
origin
Bioreactive wastes include paper, paperboard, wood products
natural fiber, food waste and yard trimmings.
Materials of not-so-recent biogenic origin are not credited.
Nonreactive materials include fossil fuels, plastics, synthetic
fibers, rubber and leather [Aren’t cows and rubber trees recent
enough?].
Climate Change Comparison: Case 1
without energy credits LF/RR=115
Annual Radiative Forcing - w/km^2
50
40
30
LF
RR
20
10
0
0
20
40
60
Time - yrs
80
100
Climate Change Comparison: Case 2
with energy credits LF/RR=45
Annual Radiative Forcing - w/km^2
14
12
10
8
LF
RR
6
4
2
0
0
20
40
60
Time - yrs
80
100
Climate Change for Four Cases
in terms of watt-years/ square kilometer
Case
Landfill
ResRecov
LF/RR
1
2528
22
115
2
635
14
45
3
2523
4.1
613
4
632
2.3
276
Concluding Observations

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Health concerns drive opposition to combustion.
Health risk usually is not considered for landfills.
Combustion wins out over landfills on health risk
especially if groundwater quality is a factor.
The climate change impacts of combustors are
significantly less than those caused by landfills.
Climate change issues are still being debated.
Environmental Health Research Needs

Improved communication of relative risks and
social tradeoffs among alternative outcomes
 Modeling and risk comparisons for fine particle
health impacts of waste management facilities
 Gas / particle partitioning of dioxins in plume and
ambient environments
 Reexamination of global warming potentials under
scenarios of continuous rather than puff emissions
Carbon Balance on Landfilled Waste
Carbon Sequestration by Forest Products
Geochemical Carbon Cycle Time Scales