lysimeter study simulate landfill disposal of cca 6 pvc columns 22 feet high, 1-foot diameter...
TRANSCRIPT
Lysimeter Study
• Simulate landfill disposal of CCA
• 6 PVC Columns
• 22 feet high, 1-Foot diameter
• Natural Precipitation infiltrates through a cap and creates leachate
Disposal Scenarios
• CCA Monofill
• Construction and Demolition (C&D) Landfill
• Municipal Solid Waste (MSW) Landfill
Construction
FRONT LYSIMETER VIEW SIDE LYSIMETER VIEW
CONCRETE
BLOCKS
SUPPORT
POST
STRAPPING STRAPPING
TREATMENT
PLANT RAILING
GROUND LEVEL
12” 12”
21’
CONCRETE
PAD
20’ WASTE
20’ WASTE
CATCHMENT
BASINS
DRAINAGE
MATERIAL DRAINAGE
MATERIAL
12”
Lysimeter Construction Layers
Layers from the Bottom-up 6-inch of washed 1” gravel Stainless steel screen 6-inch washed 1” gravel 20 feet of simulated waste Cap with distribution system Upside down cap to catch precipitation
Filling
Lysimeters
• Lysimeter 1 – Untreated wood
• Lysimeter 2 – CCA: 50% old, 50% new
• Lysimeter 3 – Typical C&D mix
• Lysimeter 4 – C&D w/CCA
• Lyimeter 5 – MSW w/untreated wood
• Lysimeter 6 – MSW w/CCA
Monofill Disposal
• No interaction of other materials with the CCA
• Lysimeter 1 – Control
• Lysimeter 2 – Experimental
• Densities– Lysimeter 1 – 593.6 pcy– Lysimeter 2 – 544.6 pcy
Lysimeter 1
Lysimeter 1 Composition by Weight
100% Untreated
Wood
Lysimeter 2
Lysimeter 2 Composition by Weight
New CCA50%
Old CCA50%
C&D Landfill Disposal
• Where typically managed in FL, landfills unlined
• Lysimeter 3 – Control
• Lysimeter 4 – Experimental
• Densities– Lysimeter 3 – 580.2 pcy– Lysimeter 4 – 603.6 pcy
Lysimeter 3
Lysimeter 3 Composition by Weight
Drywall12.4%
Concrete29.3%
Untreated Wood33.7%
Aluminum0.6%
Steel Bar0.6%
Steel Sheet0.6%Copper Wire
0.6%
Roofing13.7%
Insulation0.6%
Cardboard8.0%
Lysimeter 4
Lysimeter 4 Composition by Weight
Old CCA5.1%
New CCA5.1%
Drywall12.4%
Concrete29.3%
Untreated Wood23.5%
Copper Wire0.6%
Steel Sheet0.6%
Aluminum0.6%
Steel Bar0.6%
Roofing13.7%
Insulation0.6%
Cardboard8.0%
MSW Landfill Disposal
• Landfills lined, more expensive than C&D landfills, smaller portion of waste stream
• Lysimeter 5 – Control• Lysimeter 6 – Experimental• Densities
– Lysimeter 5 – 494.5 pcy– Lysimeter 6 – 493.0 pcy
Lysimeter 5
Lysimeter 5 Composition by Weight
MSW89%
Dog Food9%
Untreated Wood2%
Lysimeter 6
Lysimeter 6 Composition by Weight
MSW89%
Old CCA1%
New CCA1%
Dog food9%
Monitoring
• Lysimeters began operation on August 28 (Wood, C&D) and September 27, 2002 (MSW)
• Weather station records temp, rainfall, wind speed, etc. on a continuous basis
• Weekly temperature taken inside the lysimeters at 3 different depths (5, 10, 19 feet from the top of waste)
Monitoring
• Collect leachate when generated and analyze for general water quality prameters and As, Cu, and Cr
• Record volume and characterize gas produced– Test gas with Landtec Gem 500
(methane, CO2) and Jerome (H2S)
Preliminary Results
• Weekly Temp monitoring fluctuates with ambient temps
• Weekly gas monitoring – methane just detected in MSW lysimeters in last month
• Leachate generated from lysimeter 2 only, collected three dates
Lysimeter Temperatures
0
5
10
15
20
25
30
35
40
8/2
8/0
1
9/1
1/0
1
9/2
5/0
1
10
/9/0
1
10
/23
/01
11
/6/0
1
11
/20
/01
12
/4/0
1
12
/18
/01
1/1
/02
1/1
5/0
2
1/2
9/0
2
2/1
2/0
2
2/2
6/0
2
3/1
2/0
2
3/2
6/0
2
4/9
/02
4/2
3/0
2
Date
Te
mp
(C
)
Ambient
Lys 1
Lys 2
Lys 3
Lys 4
Lys 5
Lys 6
Preliminary Results – Lysimeter 2
Date
Volume (ml)
pH
As (mg/L)
Cr (mg/L)
Cu (mg/L)
9/28/01 620 6.67 3.78 0.705 0.122 1/28/02 1880 6.24 5.308 0.9575 0.2433 4/2/02 1330 5.58 6.254 0.9342 0.2728
Future
• Experiment and monitoring will continue through next May (at least)
• Once leachate is generated, gas will be monitored more frequently
• Natural precipitation will continue to be used, unless not enough leachate generated