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Environmental Concerns With Reuse and Disposal of

Chromated Copper Arsenate (CCA) Treated Wood

William Hinkley Chief, Bureau of Solid and Hazardous Waste

Florida Department of Environmental Protection

New CCA Research Sponsored by the Florida Center For Solid and Hazardous Waste Management

Gainesville, Florida

Lena Ma, PhD., University of Florida, Gainesville, Florida

Helena Solo-Gabriele, Ph.D., P.E., University of Miami, Coral Gables, Florida

Timothy Townsend, Ph.D., University of Florida,

The Center’s mission is to coordinate and engage in research relating to solid and hazardous waste management issues

Participating Institutions

UWF FAMU

FSU/ UF

USF UCF FIT

FAU FIU/U M

I. Overview of CCA Treated Wood In Florida:

Types, Amounts and Disposal Forecast

Introduction for CCA Treated Wood

Q Most Common Wood Preservative Used in the U.S. and Florida, Approx. 80% of the wood preservation market (including creosote and pentachlorophenol)

Q Represents over 97% of the waterborne wood preservative market

Introduction

0

100

200

300

400

500

600V

olum

e, m

illio

n cu

bic

feet

CCA

All Products

All Products

CCA

Production

1970 1996 Year

World Production of Arsenic Trioxide: 1998

Mexico

Belgium

Kazakhstan

Russia Other

France China

Ghana

Chile Source: USGS

1969

1971

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

U.S. Demand for Arsenic (1969 - 1998)

0

5000

10000

15000

20000

25000

30000

35000 M

etric

Ton

s

Source: USGS

Treated Wood

Agriculture Other

TX 28

17

M

E

W A

1 3

OR 10

NV

1CA 1 1

ID 5

2

AZ2

N M 1

S D

3 N E

2 KS 0

O K

3

MN 9

I A2

MO

9 AR

LA 15

WI 1 1

IL 9

IN 7

MI 11

OH11

T N 7 S

2 1 AL 3 9

F

L25

ME 1

NY

6

G A

40

SC 17 N C 28

WV

9VA 20

PA 19

VT 0 NH 1

RI 1 NJ 2

DE

0

HI 5

AK

0

MD

6

ND

1

KY 8

MT 2

W A

1 3 D

C C

B

D

E A = Low D = High B = Moderate E = Severe C = Intermediate

Introduction

WY

2A

UT CO 5

MA 3

CT 1

Introduction

The Amounts of CCA Used For Different Applications

Application Retention Value (lb/ft3)

Above ground: lumber, timbers, and plywood 0.25 Ground/Freshwater contact: lumber, timbers, plywood 0.40 Salt water splash, wood foundations: lumber, timbers, and plywood Structural poles

0.60

Foundation/Freshwater: pilings and columns 0.80 Salt water immersion: pilings and columns 2.50

Table I-2: Retention Requirements for CCA-Treated Wood (AWPA, 1996)

Motivation

Q CCA ---> Chromated Copper Arsenate

Q CCA-Treated Wood contains high concentrations of chromium, copper, and arsenic (≈1000 mg/kg for each metal)

Q When burned, metals accumulate in the ash (concentrations ≈ 10,000’s mg/kg for each)

Motivation

Unburned Wood Burned Wood

Metals Reg. Limit

(mg/kg)

Other Woods (mg/kg)

CCA-Trt Wood

(mg/kg)

Other Woods (mg/kg)

CCA-Trt Wood

(mg/kg) Arsenic

Chromium

Copper

41 DL-1.5 290-1200 7-74 8600-64,000

1,200 DL-21 1740-2400 12-140 1700-41,000

1,500 DL-8.5 1000-1100 41-190 2600-39,000

Disposal Forecast Based Upon A Mass Balance Approach

Production Use Disposal

Extrapolated from Service Life Industry 25 to 40 yearsStatistics

Disposal Forecast

Quantity of CCA-Treated Wood Sold in Florida (1996),

Q 28 million ft3 of wood product ³(17 million treated in FL and 11 million imported)

Q 6300 tons of chemical ³3000 tons as CrO3 (1600 tons as Cr) ³1100 tons as CuO (920 tons as Cu) ³2200 tons as As2O5 (1400 tons as As)

Mill

ion

ft3, d

ispo

sed

Long-term Disposal Forecast

35 Florida Statistics No Change in CCA Use

Hypothetical Case If 100% Alt. Chem. Used by 2002

30

25

20

15

10

5

0

Today Hypothetical Case Year

1964

1968

1972

1976

1980

1984

1988

1992

1996

2000

2004

2008

2012

2016

2020

2024

2028

2032

2036

2040

2044

II. Fate of CCA Treated Wood Waste in Florida

How is Discarded CCA-Treated Wood Managed in Florida?

Q It is estimated that most discarded CCA-treated wood enters the construction and demolition (C&D) debris waste stream.

Q A small amount is disposed via lined municipal waste landfills and waste-to-energy facilities.

Q Reuse and recycling is minimal.

Wood is One of the Largest Components of C&D Debris

2% 6%15% 6%

2%

27% 42%

Wood

Source: NAHB Research Center Average of 4 Sites

Plastic

Roofing

Brick

Wood

Drywall

Metal

Misc.

How is Wood in the C&D Debris Stream Managed? Q C&D Landfills Q C&D Recycling Facilities ³ Major Market: Wood Fuel ³ Growing Market: Landscape Mulch

Wood from C&D Debris

Processed C&D Wood

How is CCA-Treated Wood Managed? Q C&D debris processing facilities that

separate wood for reuse and recycling are required to remove CCA-treated wood.

Q Very difficult to accomplish. Q Very difficult to enforce. Q Facility visits indicate that very little

separation is occurring.

C&D LandfillMSW Landfill

C&D DebrisCCA-Wood Removed

from Service

C&D Processing Facility

Processed Wood

Land Application

?

Wood Fuel Facility

Separated CCA Utility Poles

CCA-Treated Wood is Visible at Times

Most of the time, the identification of CCA-treated wood is difficult, especially for wood from demolition.

Once wood is processed, separation of CCA-treated wood is not a realistic possibility.

How much CCA-treated wood is present in C&D debris wood in Florida?

Q Samples of processed wood were collected from 12 facilities around the state.

Q Samples were homogenized and analyzed for Cu and Cr Concentrations.

Q A mass balance was performed to estimate the amount of CCA-treated wood present.

Sample Collection

0

1000

2000

3000

4000

5000

6000

7000 C

r in

Ash

ed S

ampl

e (m

g/kg

) Type A

Type B

Type C Comparison of Copper and Chromium Concentrations

0 500 1000 1500 2000 2500 3000 3500 4000

Cu in Ashed Sampled (mg/kg)

Results

Q The average amount of CCA-treated wood in recovered wood from C&D waste processing facilities was approximately 6% (based on 0.25 pcf, type C).

Q This amount ranged from background levels to over 20%.

Florida Regulatory and Cleanup Criteria for Arsenic

Q Drinking Water MCL: 50 ug/L

Q TCLP: 5 mg/L

Q Soil Clean Up Target Levels (SCTLs) ³ Residential: 0.8 mg/kg ³ Industrial: 3.7 mg/kg ³ Leachable: 27.5 mg/kg

Conclusions of the 1999 National Research Council report on the Drinking Water Standard for arsenic:

“…it is the subcommittee’s consensus that the current EPA MCL for arsenic in drinking water of 50ug/l does not achieve EPA’s goal for public-health protection and, therefore, requires downward revision as promptly as possible.”

Ash from the Combustion of Wood

Q Much of the recovered wood from C&D processing is combusted as fuel.

Q Research indicates that 6% of this wood on average is CCA-treated wood.

Q The presence of CCA-treated wood in the fuel stream presents potential environmental risks in regard to air emissions and management of the ash.

Note on Arsenic

Q It is well documented that arsenic volatilizes at higher temperatures.

Q The amount of oxygen also plays a role. Q In CCA-treated wood combustion studies in the

literature, arsenic is often missing from the mass balance at the end of the study.

Q High technology air pollution control equipment must be installed at facilities whose fuel stream includes CCA-treated wood.

Characterization of Ash

Q Ash could not be obtained from the wood-burning facilities.

Q Ash was produced in an industrial furnace. Q Specific wood streams were combusted. Q Ash was chemically analyzed to assess

management options.

Summary of Wood Burns

Batch # Description of Batch Burn Time Average Burn(min) Temp. (°F)

1 Untreated Wood 90 1018 2 CCA-treated wood, 0.25 pcf 90 1014 3 CCA-treated wood, 0.60 pcf 95 1039 4 CCA-treated wood, 2.50 pcf 95 953 5 Weathered Wood 105 1030 6 C&D 1 130 928 7 C&D 2 90 821 8 C&D 3 85 829 9 Mixture 1 95 1125 10 Mixture 2 105 1005

Sample Preparation, Shredding

Sample Ashing

Florida Power & Light Industrial Furnace

Grate

Ash Catch Pan

Ash

Analysis of Ash for Direct Human Exposure Risk

Q All ash samples exceeded Florida’s residential SCTL for arsenic.

Q All samples, with the exception of untreated wood ash, exceeded Florida’s residential SCTL for chromium.

Analysis of Ash for Leachability

Q Conduct TCLP ³ Is the ash a hazardous waste? ³ How much CCA causes the ash to be

hazardous? Q Conduct SPLP ³ Will metals leach from the ash under simulated

rainfall?

Clean W

ood 0.2

5 pcf

0.6pcf

2.5 pcf

Weathere

dC&D 1C&D 2C&D 3

5% C

CA a5%

CCA b

TCLP & SPLP Comparison for Arsenic A

rsen

ic L

each

ate

Con

cent

ratio

n (m

g/l)

1000

100

10

1

0.1

0.01

TCLP SPLP

TC (5)

GWCTL (0.05)

Summary

Q The amount of CCA currently in the C&D wood stream is approximately the same amount (6%) as will result in ash from combustion of the wood to be hazardous by toxicity characteristic for arsenic, and in some cases chromium.

How Does CCA-Treated Wood Behave under TCLP? Q Discarded arsenical-treated wood is exempt

under RCRA. Q This is not recognized by all states. Q TCLP results are also used to make other

risk-based decisions regarding the management of a waste.

Consider TCLP Results for a Commercially Purchased CCA-Treated Wood Q 0.25 pcf, Type C Dimensional Lumber. Q Size-reduced to consistency of sawdust.

TCLP Results on 0.25 pcf CCA (Type C) Sawdust Le

acha

te C

once

ntra

tion

(mg/

l) 7

6

5

4

3

2

1

0 As Cu Cr

Questions Have Been Raised on the Effect of Size Reduction Q The smaller the size, the greater the surface

area available for leaching. Q Same wood sample was tested at different

sizes.

Arse

nic

Con

cent

ratio

n (m

g/l)

As TCLP Results 0.25 pcf CCA (Type C) 8 as Function of Surface Area 7

All samples = 100g 6

5

4

3

2

1

0

One Block Five Blocks Chipped Wood Sawdust

Implication of TCLP Results

Q Tests were only for one wood sample, and thus can not be used to draw conclusions for all similar wood products (more testing will be conducted).

Q Results fall within the range of previously reported data.

Q Results indicate that CCA-treated wood of this nature should not be disposed in unlined landfills.

The TCLP is Sometimes Considered Too “Aggressive”

Q The acetic acid nature of the TCLP leaching fluid is considered by some to be an unrealistic occurrence in the “real world.”

Q The SPLP has been designed to look at leaching from acid rain.

Q SPLP was conducted on the same wood sample.

Arse

nic

Con

cent

ratio

n (m

g/l)

As SPLP Results 0.25 pcf CCA (Type C) as Function of Surface Area

9

8

7

6

5

4

3

2

1

0 One Block Five Blocks Chipped Wood Sawdust

Implication of SPLP Results

Q Results for SPLP are similar to TCLP, especially for Arsenic and Chromium.

Q Confirms that CCA-treated wood should not be disposed in unlined landfills, regardless of the acidity of the leaching solution.

What About Reuse Outside the Landfill?

Q It is widely agreed that size-reduced CCA-treated wood by itself should not be used as a landscape mulch.

Q But if C CA-treated wood is occurring in processed C&D wood, how much can be present with causing undue risk?

Leaching from Land Applied Mulch

Q The SPLP is the test most commonly used to assess leaching from a land applied waste.

Q Previous SPLP results were for whole wood. Q A small number of tests were performed on

various mixtures of CCA-treated wood and untreated wood.

As Concentration in SPLP Leachate from Artificial Mulch Mixes10

TC

Ars

enic

Con

cent

ratio

n (m

g/l)

1

0.1 GWCTL

DL 0.01

0% CCA 1% CCA 5% CCA 10% CCA 100% CCA

Land Application Considerations

Q If the same approach that is used for contaminated soil is used to assess the direct human exposure risk of mulch, the wood must be free of CCA-treated wood.

Q When considering leaching, CCA-treated wood must be present at levels of less than 1% to meet current groundwater standards.

Previous Results Indicated that CCA might Leach in a Landfill

Q Small-scale laboratory leaching tests might not always present the correct picture.

Q Plus, CCA-treated wood is one of only a number of components disposed in C&D landfills. Besides untreated wood, other components are concrete, metal, drywall, etc.

Q How does CCA-treated wood behave in actual landfills?

Laboratory Column Tests

Q As part of ongoing work characterizing C&D waste leachate, C&D landfills have been simulated in the lab.

Q While laboratory testing can never fully duplicate actual landfill conditions, such testing can provide very valuable information.

Q The most recent round of laboratory tests included CCA wood as part of the waste stream.

Laboratory Leaching Columns

Composition of C&D Test Columns

8.6%

32%13.7%

Southern Yellow

2.4% Pine

1.7%

SYP CCA Drywall Concrete Metal Roofing Other

0.25 pcf Type C,29.2% CCA Treated Wood

12.4%

1 62 3 4 5

Simulated Rainfall

Experimental Design

Collect Collect Leachate Leachate

0.40 Arsenic Concentrations A

s C

once

ntra

tion

(mg/

L)

0.35

0.30

0.25

0.20

0.15

0.10

0.05

0.00

Column 1 Column 6

in Leachate

0 50 100 150 200

Time (days)

Implications of Column Study

Q Only a small amount of CCA-treated wood in the waste stream can result in leachate exceeding the groundwater cleanup target level for arsenic.

Field C&D Test Cells

Q Additional work on the characterization of C&D waste leachate involved the construction of 4 lined test cells.

Q The cells were filled with residential construction debris.

Field Test Cells

Q Leachate that resulted from rainfall infiltrating through the waste was collected and analyzed.

Q Arsenic, Copper, and Chromium were included as part of the analysis.

Cell 1

Cell 4

Cell 3Cell 2

Arsenic in C&D Test Cell Leachate

0

20

40

60

80

100

120

140

160A

rsen

ic (u

g/L)

6/11

/98

6/25

/98

7/9/

98

7/23

/98

8/6/

98

8/20

/98

9/3/

98

9/17

/98

10/1

/98

10/1

5/98

10/2

9/98

11/1

2/98

11/2

6/98

Chr

omiu

m (u

g/L)

80

70

60

50

40

30

20

10

0

Cell 1

Cell 4

Cell 3

Cell 2

Chromium in C&D Test Cell Leachate

6/11

/98

6/25

/98

7/9/

98

7/23

/98

8/6/

98

8/20

/98

9/3/

98

9/17

/98

10/1

/98

10/1

5/98

10/2

9/98

11/1

2/98

11/2

6/98

Implications of Tests Cell Results

Q The presence of CCA-treated wood may present an environmental risk during disposal in unlined landfills.

Q Leachate constituent concentrations in actual C&D debris landfills of similar waste composition will be greater (deeper waste, more compact landfill).

Arsenic Concentration in Leachate from Lined Florida Class III Landfills Which Take

Primarily C&D Waste (In ug/L)

Site Min Max Ave of Detects #Detects PBCSWA Site Cell C 7 77 21 18 PBCSWA Site Cell D 13 33 22.3 6 West Pasco 1 4 125 77.5 4

Summary of Environmental Issues Q Ash with even very small amounts of CCA

can not be applied outside the landfill. Q When wood fuel contains 3 to 5% or more

CCA-treated wood, the resulting ash will very likely be a hazardous wastes.

Summary of Environmental Issues Q Although exempt under RCRA, discarded

CCA treated wood will at times exceed the toxicity characteristic under RCRA.

Q The presence of CCA-treated wood in processed C&D wood used for mulch greatly limits this reuse option for wood. Amounts as small as 1% may cause exceedances of drinking water standards for arsenic with the SPLP.

Summary of Environmental Issues Q Leachate from C&D debris landfills

containing CCA-treated wood does contain arsenic and chromium, often at levels above regulatory limits.

Q Disposal of CCA-treated wood should be in lined landfills.

III. Potential Soil Contamination Issues

Background Concentrations ofBackground Concentrations of Arsenic in Florida Surface SoilsArsenic in Florida Surface Soils

M. Chen, L.Q. Ma, W.G. Harris & A.G. Hornsby

Soil and Water Science Department University of Florida

Geographical representationGeographical representation

Arsenic Concentrations and Frequency DistributionArsenic Concentrations and Frequency Distribution

0

10

20

30

40

50

60

70

80

90

100

110

5 10

25

10099989590

84 7573

55 50

Acc

umul

atio

n %

Median GM

DEP cleanup goal

Upper baseline limit

95% limit

<0.03 <0.09 <0.17 <0.35 <0.42 <0.8 <0.95 <1.71 <2.99 <5.58 <7.03 <16.9 <50.6

Arsenic concentrations in soils

As,

mg/

kg .

Arsenic Concentrations (ppm) inArsenic Concentrations (ppm) in Wet, Borderline and Dry soilsWet, Borderline and Dry soils

100.0 H

emis

ts

Sapr

ists

Aqu

ents

Aqu

epts

Aqu

olls

Aqu

ults

Aqu

alfs

Udu

lts

Uda

lfs

Psam

men

t

Hum

ods

Aqu

ods

BorderlineSoils (82)

GM = 0.48

Wet Soils (71) GM = 1.67

Upland Soils (288) GM = 0.27

10.0

1.0

0.1

0.0

Arsenic Concentrations in Soil Samples From Beneath CCA Treated Decks in Connecticut (mg/kg)

Deck # Deck Age

Range Avg. Background Soil Avg.

1 .3 3-19 9 2.6 2 2 7-91 34 4.2 3 5 34-99 61 4.9 4 7 44-333 139 4.9 5 7 57-215 113 2.7 6 8 50-350 138 4.4 7 15 6-80 40 1.9 Overall 3-350 76 3.7

Source: Stilwell, D.E. and K.D. Gorny. 1997. “Contamination of soil with Copper, Chromium and Arsenic Under Decks Build from Pressure Treated Wood”. Bull. Environ. Contam. Toxicol. (1997) 38:22-29

Fil Jro. 35211601$3 ,. 1

ate lllilllries 48 • Talem 88 • fm98 • Wealll!t108

----~ PLAYGROUND AT mumrn cum

Pesticide~ foundat t Kidspac~I

..• AddIUonal soil tt$ll will be ., conducted after the <hemiCJI from pl'CS"'-"'·trc'l•cd wood,.,.. found, bur tM school will opco_Moo<by. , ·

,C

NO SKATEBOARDS OR BIKE RIDING. NO BARE FEET. WEAR PROPER FOOTWEM_NO ALCOHOLIC BfYERi1ccr

0 '

HULES or .KIDS SPACE -

Arsenic concentrations in soil samples taken on 8/4/99 around the school playground

Sample ID Sample location

wt (g)

vol (L)

Response (ug/L)

dilution Concentration in soils (mg/kg)

Target % recovery

Blank Reagent blank 1.0 0.1 3.5 1 0.35 Reference SRM 2710 1.0 0.1 267.2 20 534 626 86% Reference SRM 2710 1.0 0.1 314.5 20 629 626 101%

1 under east stair ramp 1.0 0.1 32.6 1 3.26 2 east ramp-btwn boards 1.0 0.1 151.4 1 15.1 3 slide pole 1.0 0.1 65.8 1 6.58 4 under deck 1.0 0.1 89.1 1 8.91 5 front end of car 1.0 0.1 69 1 6.90 6 inside car 1.0 0.1 146.3 1 14.6 7 front ramp-btwn boards 1.0 0.1 160.6 1 16.1 8 picnic table 1.0 0.1 118.7 1 11.9 9 west pole @ swing 1.0 0.1 63.6 1 6.36 10 under seating deck 1.0 0.1 208.9 1 20.9 11 under jungle gym 1.0 0.1 141.9 1 14.2 12 under tire manhole 1.0 0.1 37.1 1 3.71 13 under "bath tub" 1.0 0.1 51.7 1 5.17 14 upper tunnel 1.0 0.1 59 1 5.90 15 under tunnel 1.0 0.1 50.5 1 5.05 16 under tunnel platform 1.0 0.1 289.8 1 29.0 17 clean soil 1.0 0.1 2.5 1 0.25 18 east steps 1.0 0.1 54.8 1 5.48 19 electric pole east 1.0 0.1 356.3 1 35.6 20 electric pole west 1.0 0.1 118.8 1 11.9 21 "bark" from e-pole west 0.5 0.1 2290 20 9160

Mean arsenic concentrations in soils = 10.9 mg /kg

TALLAHASSEE 1

CHILDREN'S PLAYGROUND

IV. Management and Regulatory Options

Mill

ion

ft3, d

ispo

sed

Long-term Disposal Forecast

35 Florida Statistics No Change in CCA Use

Hypothetical Case If 100% Alt. Chem. Used by 2002

30

25

20

15

10

5

0

Today Hypothetical Case Year

1964

1968

1972

1976

1980

1984

1988

1992

1996

2000

2004

2008

2012

2016

2020

2024

2028

2032

2036

2040

2044

Sources Of Construction and Demolition Debris Waste In The U.S. (EPA, 1998)

Sources of Construction and Demolition Debris in the U.S. (EPA, 1998)

Commercial NewConstruction

3% Residential New Construction

5% Residential Demolition

15% Commercial Rennovation

21%

Commercial Demolition 33%

Residential Rennovation 23%

Construction and Demolition (C&D) Landfills In Florida

Q 168 Permitted Sites Total:

³ 97 All C&D Debris

³ 71 Landclearing Debris Only

³ Down from 278 in 1996

Q Sites taking all C&D Debris must have ground water monitoring, financial assurance, other BUT no liners

Potential Management Options For CCA Treated Wood

Q Source separation at const./demolition sites Q Identification/separation at C&D MRFs Q Work with large end-users (e.g. utilities,

FDOT, agriculture) Q “Take back” program for poles and pilings Q Mark/stamp CCA and non-CCA wood

Sorting Study

Sorting Study Results: Construction Debris

Lumber - CCA Cutoffs 5%

10% Plywood - CCA

8%

Cutoffs - CCA 15%

Plywood 35%

Pallets 8%

Lumber 19%

Identifying CCA-Treated Wood in Mixed Wood Streams Treated Untreated

Q Chemical Stains Very Promising Advantage: Low Capital Cost Disadvantage: Labor Intensive

Q X-ray Fluorescence Very Promising Advantage: Potential for On-line System Disadvantage: Cost

Potential FDEP Regulatory Options For CCA Treated Wood

Q Prohibit disposal at unlined C&D landfills Q Require disposal in lined landfills Q Require separation at C&D MRFs Q Prohibit production of mulch from CCA wood Q “Unadopt” CCA exemption in 261.4(b)(9)CFR Q Remediation at existing C&D sites?

Estimates of Mercury in Florida Discards (Tons) Product/Year 1995 1996 1997 2000 Hsehold Batteries 7.42 5.63 3.65 1.24 Electric Lighting 1.11 1.17 1.25 0.98 Switches, thermostats 2.96 2.97 2.93 3 Other (amalgams, etc) 0.44 0.41 0.38 0.3 Total 11.93 10.18 8.21 5.52

Estimates of Lead in Florida Discards (Tons) Product/Year 1995 1996 1997 2000 Veh. Batts (95%recy) 4646 1524 2567 2586 Small Sealed Batts 339 377 402 572 TV Tubes 1144 1144 1144 1768 Computer CRTs 691 742.00 736 1033 Glass&Ceramics 450 453 456 463 Circuit Bds 141 123 105 51 Plastics 166 137 124 127 Other(solder, cans) 169 144 142 138 Total 7745 4644 5676 6738

Estimates of Cadmium in Florida Discards (Tons) Product/Year 1995 1996 1997 2000 NiCd Batteries 100.24 112.99 123.86 185.43 Plastics 10.47 10.49 10.52 10.58 Pigments 0.52 0.52 0.52 0.52 Plating 4.11 3.00 3.07 1.51 Other (Rubber, misc) 6.92 7.62 2.56 2.65 Total 122.26 134.62 139.93 200.69

V. Alternative Wood Preservatives

Alternative Wood Preservatives Chemicals Meeting These Criteria

Q AAC: Alkyl Ammonium Compound (a.k.a. DDAC) Q ACC: Acid Copper Chromate Q ACQ: Ammoniacal Copper Quat Q Borates Q CBA: Copper Boron Azole Q CC: Ammoniacal Copper Citrate Q CDDC: Copper Dimethydithiocarbamate

Alternative Chemicals - Status Q AAC - Three AAC manufacturers were contacted

and all indicated that AAC is not generally marketed as a “stand-alone” wood preservative. Ü ACQ, Cu + AAC.

Q Borates - Can not be used outdoors Ü taps into a NEW treated wood market, “whole house”

Q ACC - Contains Chromium

Remaining Chemicals: ACQ, CBA, CC, CDDC

Use Product ACQ Type B&D

CBA CC CCA CDDC

Above ground lumber, timbers, ties 0.25 0.204 0.25 0.25 0.10*

Above Ground plywood 0.25 0.25E 0.25 Soil or Water Use lumber, timbers, ties 0.40 0.40 0.40 0.20 Soil or Water Use plywood 0.40 0.40 0.40 General Construction posts and columns 0.40 0.40 0.40 0.20 Structural Composites lumber & timbers 0.60 0.60 0.20 Used on Permanent Wood Foundations

lumber & plywood 0.60 0.60

Highway Construction poles 0.60 0.60 Land and Freshwater Foundations

piles 0.80

Marine & Coastal Waters

lumber, timbers, ties, & plywood

2.50 2.50

Marine & Coastal Waters

piles 2.50

AWPA Standardization, Values Provided are Chemical Retention

Alternative Chemical Costs

Costs for a 12 foot deck board (1 1/4” x 6 “)

CCA CDDC ACQ ACQ with Water Repellant

$8.94 $10.29 $9.90 $11.47

($6.99-$11.69) ($9.28-$12.00) ($9.29 - $10.50) ($9.95-$14.25)

n=15 n = 16 n = 2 n = 10

Restrictions and Bans on CCA in Other Countries

Q Total bans: Switzerland, Vietnam, Indonesia

Q Restrictions: Japan, Denmark, Sweden, Germany

“The ACQ preservative in Preserve treated wood is a copper plus quat system that provides the same level of protection to wood as CCA preservatives against decay, rot and termite attack without the use of arsenic and chromium.”

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s:•., rs s:11•""• • .flollY•G 8•• ,,!'! .. , ,ii :AQswers to

commonly asked ) uestions

“…Copper Azole is a significant improvement over traditional CCA treatment as it substantially reduces reliance on and exposure to the more toxic heavy metals such as chromium and arsenic throughout all stages of production, distribution and use. …it is environmentally responsible to specify or use Copper Azole treated lumber.”

Announcing New Tanallth® E

Koppers:.l::llclison Is pleased to announce the New Zealand launch of our new non-chromiurT1., non-arseni Qreservative product, Tanallth®E.

Why a new product 7

Tanalith® CCA has a proud record of use in NZ for more than 50 years, and internationally fo, longer still. In this time h has been proven to be an effective and safe product to use, protecting countless millions of cub~ metres of timber from blofogicar attack. As effective as it is however, the continued use of CCA is corr1n9 under 1hrrun .d.u&__t_Q the po1enua1 and pe1ce1ved throats posed oy 1rie ,nc1us1on of t\ed~ metals 111,;e chromium arid arsen~ ~tJ11Qred•en1s­

The threats to CCA use have arisen In different forms in different countries. In Japan, CCA is t1t11ng out of filvou.r oue 10 re~ons on landfill di~sal of treated WOod that has been removed from se!Vlce, and also difflelJlty meeting tough Slormwater limits at treatment plants fo, arsenic. In parts of Scandinavia, CCA use has been restricted to in-ground and lnduSlrlat timber applications only.

Closer to home, we lind that due to percaived risks and the wish to promote an "eco-lrlendly" Image, no CCMreated WOod may be used In the Sydney OIY'll)lc VIiiage; tbe NSW Department of Public Works Is Intending to adopt the same policy tor a.II tt's construction from 2000 on.

tn NZ no restriction& have so far been tmposed oo CCA use, t-1,_1wever ;round cun1art11r1.111on 3n-:Js1urn1waler d1sc:11a,g~ l!lnl!S may fo,ce rre<11~rs an,t , e:a1lers ltJ upgral'Je storage af83S to m1n11nlS& lh& 1n1~ olJ Q.a.cil,ate trom lreolllY. C.CA· l<tUIIQ,.j WOOCI

The 111ck!iot1 wcutd-w1r1e g,oup of compdn1e.; (of which Ko~Js:l;.!lckson Is a member) t"fav~ oeen avnue ot lhttse tJnvet9p1rtg_ tre,,u1s tor >ome 1ur11,, aod have been develop ng Tanalith® E as a possible CCA-altsrnalive.

Ko ppers-Hlc.kson Timber Protection (New Ze.al.,ndJ Umlted

“The aim of the development program was to create a wood preservative that had the same excellent timber durability properties as CCA but without the inclusion of chromium or arsenic. An additional desired feature was complete compatibility with existing CCA treatment plants and processes.”

Key Unknowns

Q Current EPA re-registration review and recommendations in RED (Spring, 2000?)

Q Revisions to As MCL (Jan, 2001?) Q Results of As Bioavailability Study Q Additional FL soil contamination studies Q Actions by the European Community