Download presentation
Presentation is loading. Please wait.
Published byEileen Leonard Modified over 9 years ago
1
Disposal Strategies for CCA-Treated Wood August 13, 2003 National RCRA Conference Washington D.C.
2
Funding Received from Florida Center for Solid and Hazardous Waste Mngt. Florida Power and Light Sarasota County Florida Department of Environmental Protection Florida International University/NIEHS Rutgers University/NIEHS
3
Helena Solo-Gabriele, Ph.D., P.E., Assoc. Prof., Civil/Environ. Engrg Lora Fleming, M.D., Ph.D. Assoc. Prof., Epidemiology/Ph.D. Timothy Townsend, Ph.D. Assoc. Prof., Environ/Solid Waste Engrg Yong Cai, Ph.D. Assist. Prof., Chemistry Active Faculty Researchers
4
Students Supported on Project Sean Bennie Kenneth Brown Vandin Calitu Zhangrong Chen 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 Tomoyuki Shibata Jin-Kun Song Kristin Stook Sheena Szuri Thabet Tolaymat Lakmini Wadanambi
7
Untreated SYP CCA-Treated 0.25 pcf CCA-Treated 0.60 pcf CCA-Treated 2.5 pcf Above Ground Structural Poles Saltwater Splash Saltwater Immersion Pole/Pilings
8
Background CCA Chromated Copper Arsenate As toxic to humans, carcinogen Cr toxic to humans, carcinogen Cu toxic to aquatic organisms Toxicity Fn of Speciation As(V) and As(III) toxic with As(III) more toxic Cr(VI) more toxic than Cr(III)
9
Regulatory Issues CCA currently under-going reregistration Industry issued a nation-wide phase out for CCA used in residential applications Exempt at federal level from being classified as a hazardous waste during disposal
10
Original Motivation For Project Ash Disposal Problem
11
How Much CCA-Treated Wood is Disposed?
12
Disposal Model
13
How Much CCA-Treated Wood in Florida? (Preliminary)
14
Amount of CCA-Treated Wood To Be Discarded Cumulative Volume Imported = 660 million cubic feet Volume in Service = 440 million cubic feet Statistics for the Year 2003 (Florida) 216,000 miles of 2 x 4’s 100 yds x 50 yds x 2.7 miles 9 times around
15
How Much CCA-Treated Wood In Florida? (Preliminary)
16
C&D Landfill MSW Landfill C&D Debris Recycling Facilities CCA-Wood Removed from Service Processed Wood (6% CCA in 1996) Land Application Wood Fuel Facility Ash
17
Background Research conducted found CCA-treated wood in C&D waste piles 6% in 1996 (12 C&D facilities) 9 to 30% in 1999 (3 C&D facilities) 22% in 2001 (1 C&D facility studied extensively)
18
Background (From SFPA) U.S. Statistics for Southern Pine Production
19
C&D Landfill MSW Landfill C&D Debris Recycling Facilities CCA-Wood Removed from Service Processed Wood (6% CCA in 1996) Land Application Wood Fuel Facility Ash
20
Disposal Through Wood Ash Industrial Furnace Grate Ash Catch Pan Shred Ashing
21
Leaching of Wood Ash - Total Arsenic
22
Wood Ash The presence of CCA-treated wood as 5% of the wood mix caused the ash to be characterized as hazardous.
23
Leaching of Wood Ash - Speciation As,SPLP
24
Leaching of Wood Ash – Speciation Cr,SPLP
25
Leaching of Wood Ash – Speciation Cr,SPLP
26
C&D Landfill MSW Landfill C&D Debris Recycling Facilities CCA-Wood Removed from Service Processed Wood (6% CCA in 1996) Land Application Wood Fuel Facility Ash
28
Leaching of Mulch SamplesNo.No. Exceeding GWCTL for As No. Exceeding GWCTL for Cr C&D Debris20185 Yard Waste311 Colored Mulch 320 Vegetative Mulch 300
29
Leaching of Mulch
30
Mulch n Must contain < 0.2 % CCA-treated wood in order to pass GWCTL
31
C&D Landfill MSW Landfill C&D Debris Recycling Facilities CCA-Wood Removed from Service Processed Wood (6% CCA in 1996) Land Application Wood Fuel Facility Ash
32
TCLP Results – Total TCLP Limit
33
Leaching - Speciation
34
Possible Solutions “Short–Term” Solution Develop Strategies By Which to Better Manage CCA-Treated Wood “Long-Term” Solution Use Wood Treated With Non-Arsenical Preservatives
35
Long-term Solution Use Wood Treated With Non-Arsenical Preservatives
36
Alternative Chemicals Contain no arsenic Have been used commercially to some extent Standards provided by the AWPA Waterborne preservative Chemicals Considered
37
Phase I: Alternative Chemicals AAC: Alkyl Ammonium Compound (a.k.a. DDAC) ACC: Acid Copper Chromate ACQ: Ammoniacal Copper Quat Borates CBA: Copper Boron Azole CC: Ammoniacal Copper Citrate CDDC: Copper Dimethydithiocarbamate Chemicals Initially Considered
38
General Comments About Remaining 4 Alternative Chemicals Efficacy Depletion/Leaching Corrosion Mechanical Properties Costs Just as Effective for Standardized Products Leach less As but more Cu Similar to CCA Some require SS fasteners Cost 10 to 30% more
40
Leaching Tests Synthetic Rainfall
41
Toxicity Tests Less Toxic CCA CDDC CBA ACQ CC
42
“Short-term” Solution for the Disposal Problem Develop Sorting Technologies
43
C&D Landfill MSW Landfill C&D Debris Recycling Facilities CCA-Wood Removed from Service Processed Wood (6% CCA in 1996) Land Application Wood Fuel Facility Ash Add a Wood Sorting Step CCA-Treated Wood 99.9% Untreated Wood
44
Objective Construct and Operate an On-Line System for Sorting Treated From Untreated Wood
45
Most of the time, the identification of CCA-treated wood is difficult, especially for wood from demolition.
46
Sorting Technologies Low Capital Cost, Labor Intensive Chemical stains UntreatedTreated
47
Suitable for On-Line System, High Capital Costs X-ray Technology (XRF) Laser Technology (LIBS) Sorting Technologies
48
DETECTORS laser x-ray
49
Laser configuration Laser To PC
50
Wood Plasma Caused By Laser
51
Output signal for detection of treated wood Strobe Light On -Positive
52
LIBS Spectrum of CCA-treated Wood
53
Analysis of single laser shots Treated Lumber Untreated Lumber 100% accuracy 99% accuracy 10-shot average 92% accuracy 95% accuracy Single-shot analysis Cr Signal
54
Summary of LIBS Results Successfully detect CCA-treated wood by presence of chromium in the field Indicator strobe enables real-time, on-line sorting with accuracy approaching 100% Some inefficiencies noted in this study wet wood and surface coatings. Can be overcome with a more powerful laser.
55
X-ray Detector ¾”
56
Treated vs. Untreated Wood
57
Dry vs. Wet Treated Wood
58
Alternative Chemicals
59
Distance readings
60
XRF Summary Advantages Very consistent. It can not only differentiate between treated and untreated wood but gives the actual amount treated in specific units. Disadvantages Limited to no more than 1” distance.
61
Sorting Summary Both X-ray & Laser Methods Are Very Promising Improvements, Develop Logic Between Detector and Shear Arm Full Scale Field Demonstration Recommended to Further Substantiate Performance and Cost Effectiveness
62
Ultimate Disposal?
63
Lysimeters 2 Monofills / 2 C&D / 2 MSW Untreated (mg/L) Treated (mg/L) Wood Monofill (100% wood) < 0.025 – 43 As(III), As(V) C&D Waste (34% wood) <0.060.4 – 1.8 As(III), As(V), DMAA, MMAA MSW (2% wood) < 0.70.4 – 2.3 As(III), As(V), DMAA, MMAA
64
Overall Recommendations Arsenic and Chromium burden will continue to increase even with proposed industry phase out Switch to alternative chemicals + for terrestrial systems - for aquatic ecosystems (Cu) Sorting will be necessary At Source At C&D Facilities Disposal Within Lined Landfills Preferred Over Unlined Landfills, Mulch, and Ashing
65
Questions? www.ccaresearch.org hmsolo@miami.edu
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.