History of Research Project on CCA-Treated Wood

Presented May 6, 2002Gainesville, Florida

Funding Received from

Florida Center for Solid and Hazardous Waste Mngt.

Florida Power and LightSarasota County

Florida Department of Environmental ProtectionFlorida International University/National Institute for

Environmental Health Science

Helena Solo-Gabriele, Ph.D., P.E.,

Assoc. Prof., Civil/Environ. Engrg

Timothy Townsend, Ph.D.

Assoc. Prof., Environ/Solid Waste Engrg

Yong Cai, Ph.D.

Assist. Prof., Chemistry

Active Faculty Researchers

Students Supported on Project Sean Bennie Kenneth Brown Vandin Calitu Brajesh Dubey Tim Franklin Kelvin Gary Myron Georgiadis Naila Hosein Kendiro Iida Gary Jacobi Jenna Jambeck Bernine Khan

Monika Kormienko Brian Messick Tom Moskal Jennifer Penha Donna May Sakura Catalina Santamaria Ajay Seth Jin-Kun Song Kristin Stook Thabet Tolaymat Lakmini Wadanambi

Background

CCA-Treated Wood is the most common wood preservative used today (>80% market)

CCA ---> Chromated Copper Arsenate

Background

Above Ground

Structural PolesSaltwater Splash

Saltwater ImmersionPole/Pilings

pcf = pounds of CCA per cubic foot of wood

20,000 mg/kg As

2,000 mg/kg As

Background

CCA ---> Chromated Copper ArsenateThe treated wood contains very high concentrations of Cr, Cu, and As

As toxic, known carcinogen

Soil background levels for arsenic in Florida are low

Strict disposal guidelines

Why Was this Project Initiated?

High metals concentrations were observed in the ash from wood cogeneration facilities located in Florida

Year 1 (1996-1997)

Year 1: Disposal Forecast

0

5

10

15

20

25

30

3519

64

1968

1972

1976

1980

1984

1988

1992

1996

2000

2004

2008

2012

2016

2020

2024

2028

2032

2036

2040

2044

Year

Mill

ion

ft3

, dis

po

se

d

No Change in CCA Use

Today Hypothetical Case

If 100% Alt. Chem.Sold by 2002

C&D LandfillMSW Landfill

C&D Debris Recycling Facilities

CCA-WoodRemoved

from Service

Processed Wood (6% CCA in 1996)

Land Application

Wood Fuel Facility Ash

Year 2 (1997-1998)

Year 2

Develop Tools for Disposal End Management

Leaching Studies, ash Hazardous when CCA-treated wood represents

5% of wood burned

Solvents can extract metals from ash, citric acid very promising (40 to 100% As removed) ------> Explore Potential Recycling?

Year 2 (continued)

Sorting Studies, Laboratory Chemical stains, low capital cost

labor intensive

X-ray methods, high capital costsuitable for on-line system

Untreated Treated

Year 3 (1998-1999)

Year 3

Disposal-End Management

Field Demonstration of Sorting Technologies Stains suitable for sorting small quantities of wood

Evaluation of Pyrolysis Technology Appears promising for ultimate disposal

Resource book for Wood Disposal Sector

Year 3 (Continued) Alternative Chemicals

Four Promising Alternative Chemicals for CCA: ACQ, CBA, CC, CDDC

All standardized for applications requiring 0.25 & 0.4 pcf Comparable to CCA: efficacy

Leach less As but generally more Cu

Cost 10 to 30% more at retail establishment

Ash Problem

Inventory

SortingLab

Ash Char & Trt

SortingField

Alt. Chem.Lit Review

Year 1

Year 2

Year 3

The Research Team Was Invited to the Minnesota Proceedings

Minnesota’s Listed Metals Advisory Council[Cd, Pb, Hg, and Cr(VI)]

Speciation Debated

In-Service Issues Debated

Lack of Scientific Data

Year 3 Supplemental

Impacts of CCA on Soil during In-Service Use

Use Sectors for CCA-Treated Wood

Leaching of CCA-treated Wood and C&D Debris Wood Mulch

Literature Reviews, Alt. Chem.Cr & As Speciation

Minnesota

Lit ReviewsAlt Chem, As, Cr Spec

DeckStudy

Leaching Wood & Mulch

UseSectors

Leaching of CCA During In-Service Use

Year 3 Supplemental

Leaching of CCA-Treated Wood During In-Service Use

Year 3 Supplemental

Chemicals Do Leach from CCA-treated Wood During In-Service Use

Leaching of CCA-Treated Wood During In-Service Use

0

10

20

30

40

50

60

70

80

90

BP BR PP LT TB MG AD TP OP

Ars

en

ic C

on

cen

tra

tio

n (

mg

/kg

)

Control Under Deck

Gainesville MiamiTallahasseeNot CCA-Treated

FDEP Industrial SCTL

Leaching of CCA-Treated Wood During In-Service Use

0

2

4

6

8

10

12

0 10 20 30 40 50 60 70 80

Arsenic Concentration (mg/kg)

Approximately 39 square miles of Florida land covered by CCA-treated decks. Top 8 inches of this area would correspond to 60 million tons of soil.

Use Sectors for CCA-Treated Wood

Year 3 Supplemental

Use Sectors for CCA-Treated Wood

Marine & Freshwater Applications

16%

Outdoor Decks, Landscaping,

Fences, & Highway

Construction

Utility Poles5%

Alternative ChemicalTreated Wood Available for These Uses

79%

Year 3 Supplemental

28,600 tons of As, Cumulative

1600 tons Asimported per year In-service losses (10%):

2900 tons

Disposed to date:1600 tons

Future disposal(for that imported through 2000):

24,100 tons

Year 3 Supplemental

Leaching of CCA-treated Wood and

C&D Debris Wood Mulch

Year 3 Supplemental

Leaching of CCA-Treated Wood

0

5

10

15

20

25

30

35

40

TCLP SPLP EPTOX WET

As

Co

nce

ntr

atio

n (

mg

/L)

Sawdust

Chipped Wood

5 20-g Blocks

100-g Block

TCLP Limit

Leaching of Mulch

Samples No. No. Exceeding GWCTL for As

No. Exceeding GWCTL for Cr

C&D Debris 20 18 5

Yard Waste 3 1 1

Colored Mulch

3 2 0

Vegetative Mulch

3 0 0

Year 3 Supplemental

Ash Problem

Inventory

SortingLab

Ash Char & Trt

SortingField

Alt. Chem.Lit Review

Minnesota

Lit ReviewAlt Chem, As, Cr Spec

DeckStudy

Leaching Wood & Mulch

UseSectorsSorting

Field

FDEP/SarasotaInnovative Recycling Grant

laser

x-ray

Innovative Recycling Grant

Output signal for detection of treated wood

Strobe LightOn -Positive

Alt ChemLeach/Tox

UnderReview

As & Cr Spec

On-going

Mulch Study

Proposed

Ash Problem

Inventory

SortingLab

Ash Char & Trt

SortingField

Alt. Chem.Lit Review

Minnesota

Lit ReviewAlt Chem, As, Cr Spec

DeckStudy

Leaching

Wood & Mulch

UseSectors

SortingField

FDEP/SarasotaInnovative Recycling GrantCompleted

Add’l Deck & Dock

FIU/NIEHSOn-going

Alt ChemLeach/Tox

UnderReview

As & Cr Spec

On-going

Mulch Study

Proposed

Ash Problem

Inventory

SortingLab

Ash Char & Trt

SortingField

Alt. Chem.Lit Review

Minnesota

Lit ReviewAlt Chem, As, Cr Spec

DeckStudy

Leaching

Wood & Mulch

UseSectors

SortingField

FDEP/SarasotaInnovative Recycling GrantCompleted

Add’l Deck & Dock

FIU/NIEHSOn-going

Questions?Comments?

Reports available atwww.ccaresearch.org