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