Your search resulted in 43 documents. Displaying 25 entries per page.
Termite resistance of pine wood treated with chromated copper arsenates
1997 - IRG/WP 97-30128
Two four-week, no-choice laboratory tests were performed with CCA-treated southern yellow pine and radiata pine against Formosan subterranean termites, Coptotermes formosanus. CCA retentions as low as 0.05 kg/m3 (0.03 pcf) provided protection from all but light termite attack (rating of 9 on a 10-point visual scale). Similar and consistent light attack on wafers containing retentions as high as 6.4 kg/m3 (0.4 pcf), coupled with complete termite mortality, demonstrates that the mode of action of CCA treatments relies upon toxicity rather than having any repellent effects against termites.
J K Grace
An introduction to environmental aspects of groundwater arsenic and CCA treated wood poles in Bangladesh
1997 - IRG/WP 97-50081
The environment comprises biosphere, lithosphere, atmosphere and hydrosphere. Therefore, environmental science is a multi-disciplinary study, includes life sciences, physical sciences, chemical sciences, geology, geography, meteorology, forestry, agriculture, soil science, hydrology, ecology, public health, engineering etc. Tremendous industrial and mining activities, deforestation and population explosion are threatening the very existence of life on earth.Groundwater is used for irrigation, drinking and other domestic purposes where other sources of water are not plenty. Groundwater contain different metals resulting from soluble minerals, deposited in ground during its origin. Thus concentration of metals in surface soils and water are increased day by day by lifting of groundwater. Surface soils and water also receive metals from industries and mines and as a result of multipurpose use of products from those. Deforestation is controlled by plantation and preservation of forest products by different wood preservatives. Recently groundwater in some underground rocks of Tertiary and Quarternary age in Bangladesh is very often known to contain arsenic (As) above permissible limits . On the other hand chromated copper arsenate (CCA) impregnated wooden poles has been used for rural electrification in Bangladesh since 1979. It is an attempt to find out through research and review of literatures that whether the groundwater As is contaminatable from As used in wood poles and whether the components of CCA cause environmental problems. Possible way of purification of arsenic containing groundwater for drinking have been suggested.
A K Lahiry
Performance of chromated copper arsenate-treated aspen fence posts installed in Forintek's Eastern test plot from 1951 to 1963
1984 - IRG/WP 3272
Aspen poplar fence posts were pressure treated by the full cell process using three formulations of copper chrome arsenate wood preservative. A total of one hundred and fifty nine of the posts were installed in service in Forintek's Chalk River post plot from 1951 to 1962. During the 1982 general inspection of the post plot all 159 posts were still in service. A groundline inspection was carried out on the material to determine the extent to which decay had progressed during this period. Samples were taken from the surface of tanalith C treated posts and subsequent microscopic examination revealed that soft rot attack was present in the outer portion of posts. The groundline area of posts treated with (K 33), CCA type B and (greensalt) CCA type A were in generally good condition after 22 years and 31 years respectively. Rate of decay was highest for CCA-C tanalith treated posts at 0.3 mm per year with a retention of 3.04 kg/m³ oxides.
C D Ralph
Treatability of Siberian larch and spruce with chromated copper arsenate
1996 - IRG/WP 96-40060
Heartwood of Siberian larch (Larix gmelini) and spruce (Picea jezoensis) was pressure treated with chromated copper arsenate (CCA) Type B using a full cell process. Larch heartwood was somewhat difficult to treat than the spruce, although both species did not meet a minimum requirements of penetration and retention specified by the American Wood Preservers' Association (AWPA) for difficult to treat wood species in ground contact. To improve the preservative treatability of refractory larch and spruce, end matched heartwood lumber had been incised using either a conventional or a double density incising pattern, and then pressure treated with CCA Type B. The use of double density incising is necessary for spruce heartwood in order to acheive adequate treatment with CCA; however, the increase in incision densities and/or the use of high treating pressure may be required for adequate treatment of larch heartwood.
Gyu-Hyeok Kim, Woo-Gue Jee, Jae-Jin Kim
Investigation of the fixation in wood of chromated zinc chloride and copperised chromated zinc chloride preservatives
1976 - IRG/WP 372
A biological method of evaluating the extent to which CZC and CCZC preparations are retained in wood in terms of the potential protection which they afford against destruction by Merulius lacrymans (dry rot) is given. CCZC is recommended for protection of wood under moderate leaching conditions, while the use of CZC under such conditions is not recommended.
V N Sozonova, D A Belenkov
A Soil Bed Test of the Effect of CCA Penetration on the Performance of Hem-fir Plywood
2004 - IRG/WP 04-30332
An accelerated decay test was set up to compare the performance of CCA-treated Western hemlock/amabilis fir plywood treated to meet the preserved wood foundation (PWF) retention standard with various patterns of preservative penetration. Short lengths of treated plywood and comparable untreated material were installed in a soil bed. After eleven years of exposure, the CCA treatments were all sound regardless of penetration, while the untreated material had failed due to decay within three years.
P I Morris, J K Ingram
Fixation of chromated copper arsenate (CCA) wood preservative in Australian hardwoods: A comparison of three Eucalyptus species
1996 - IRG/WP 96-30107
New environmental guidelines for the management of CCA treatment plants were released in Australia in 1995. This has stimulated interest in techniques for controlling or accelerating the fixation of CCA in freshly treated timber products. The ability to understand, then effectively control and/or accelerate fixation of CCA in treated timber products can be an economic, technical and environmental advantage. Data available on fixation of CCA in timber commodities however, is mainly on softwood not hardwood species. In this paper, the rate of fixation of CCA Type C Oxide in poles of three species of Australian Eucalyptus was monitored over a six week period following treatment. These results will assist in the design of adequate drip pad and undercover storage area for pole treaters in South East Queensland.
Acceleration of the fixation of chromated wood preservatives by UV-radiation
1989 - IRG/WP 3544
Preliminary laboratory tests demonstrated that the fixation of chromated water-borne wood preservatives may be accelerated by UV-radiation. The degree of fixation depends on the intensity of radiation and the prevailing temperature. Three hours radiation at 20°C in a device for artificial weathering diminished the leaching of chromium to 43% and of copper to 23% compared to not-radiated samples. Two hours radiation at 60°C gave almost complete fixation. Five to seven seconds radiation in a high energetic commercial plant for hardening of paints diminished the leaching of chromium to 75% and of copper to 30% and a second radiation of the same samples still increased the fixation. Further tests are necessary to obtain more details on the use of UV-radiation for fixation in practice.
H M Illner, H Willeitner, K Brandt
Wood Preservatives Science Issues: US EPA’s Perspective
2005 - IRG/WP 05-50224-2
The USEPA Office of Pesticide Programs (OPP), Antimicrobials Division (AD), regulates the use of chemicals registered as wood preservatives in the United States. An overview of the registration and re-registration process is presented. The wood preservatives data requirements include toxicological, human exposure, ecological, and environmental fate data. A detailed discussion of wood preservatives data requirements is presented. Currently, the three heavy duty wood preservatives (Pentachlorophenol, Chromated Copper Arsenate, and Creosote) are undergoing the re-registration process. This process is mandated by Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). The re-registration process ensures that older pesticides meet contemporary safety standards and data requirements. The challenges of regulating the treated wood will be discussed.
Effects of surfactants and ultrasonic energy on the treatment of wood with chromated copper arsenate
1977 - IRG/WP 3108
Sugar pine stakes 1'' x 1" x 16" were treated by a hot-water bath followed by soaking in cold CCA solution for 10 to 30 minutes. A similar number of stakes were treated by a cold-cold bath. Half of the stakes were subjected to ultrasonic energy during the CCA bath. The mean absorption for stakes given the hot-cold bath was 18.52 pcf (297 kg/m³) and 4.64 pcf (74 kg/m³) for those given the cold-cold bath. The rates of absorption were o.323 pcf (5 kg/m³) per minute and 0.053 pcf (0.85 kg/m³) per minute, respectively. The relationship between absorption in pounds per cubic foot (Y) and soaking time in minutes (X); Y = 12.27+0.323 X, was linear and significant. The linear relationship for the cold-cold treatment was poor (r = 0.305). Neither ultrasonic energy, nor its interaction with soaking time, had a significant effect on solution absorption for either the hot-cold or cold-cold treatments. In a second series, the stakes were treated in the CCA solution with a 3-minute dip, a 48-hour cold soak, and Lowry pressure. Half of the stakes were treated in the solution to which a surfactant had been added. The interacting effect of surfactant and method of treatment was significant. The highest absorption was obtained when the specimens were treated with the solution containing the surfactant by the Lowry method, 35.13 pcf (563 kg/m³). In comparison, the absorption was 22.55 pcf (361 kg/m³), 36 percent lower, when surfactant was not used. The surfactant had a beneficial effect on the results of the 3-minute dip, but not the 48-hour soak.
C S Walters
Equilibrium distribution of toxic elements in the burning of impregnated wood
2001 - IRG/WP 01-50172
The current work focuses on predicting the behavior of arsenic, chromium, and copper in the burning of impregnated wood. A theoretical method is used to study the chemistry of the system, with special interest directed towards the vaporization tendency of the potentially toxic elements. The core of the study is the global equilibrium analysis that simultaneously takes into consideration all chemical reactions. The results of the present study indicate that chromium and copper are unlikely to volatilize at combustion temperatures. Arsenic appears to be more volatile. Nevertheless, the prediction showed that it may be captured by calcium of the wood ash, and small amounts are likely to dissolve in the slag-phase of the ash. It may also form non-volatile compounds with magnesium, copper, and chromium and other elements of the impregnated wood, which efficiently hinders its emissions as gaseous species.
K Sandelin, R Backman
Soft-rot control in hardwoods treated with chromated copper arsenate preservatives. Part 3: Influence of wood substrate and copper loadings
1977 - IRG/WP 2100
The hypothesis is proposed that hardwoods need more chromated copper arsenate (CCA) than softwoods to protect them from soft-rot attack mainly because hardwoods are more readily consumed by soft-rot fungi. Simple model systems, using copper-supplemented agar or groundwood pulp treated with CCA showed that fungi tolerated more toxicant (copper) as more available substrate (malt) was provided. Soft-rot tests with CCA-treated hardwood blocks provided typical dosage-response curves when results were expressed as a ratio of substrate to toxicant (wood to copper). Furthermore, hardwoods needed 10 to 20 times more copper as CCA than softwoods to prevent soft-rot attack. When CCA was substituted by ammoniacal copper arsenate in 5 hardwoods, similar threshold values for soft-rot attack were obtained in terms of a wood-to-copper ratio. Hence, CCA may be behaving poorly against soft-rot fungi in our hardwood specimens mainly because the substrate contained too little copper. The practical implications of these results are discussed.
M A Hulme, J A Butcher
Incomplete fixation of chromium in the pre-treated wood with a solution of copper and arsenic compounds
1995 - IRG/WP 95-50052
Ponderosa pine wood thin sections were treated with a combination of chromium, copper, and arsenic chemicals. The wood sections was analyzed by electron spin resonance spectrometry (ESR) and X-ray photoelectron spectrometry (XPS) to elucidate the mechanism of fixation of the chromated-copper preservatives. The wood subjected to the two-step treatment with copper and arsenic followed by chromium exhibited a strong Cr(V) ESR signal. However both Cr(III) and weak Cr(V) signals were observed in wood subjected to the one-step treatment containing chromium, copper, and arsenic. XPS spectra also supported the Cr(V) formation in the former treatment. The further chromium reduction from Cr(V) to Cr(III) for samples treated in two steps did not proceed very well during the fixation period of 3 months. Copper arsenate formed in the wood could disturb the interaction of chromium with the wood. These results indicate that re-treatment of wood with chromium containing preservatives may result in incomplete fixation of chromium.
J N R Ruddick, K Yamamoto, F G Herring, P C Wong, K A R Mitchell
Preservative treatment of Golpata (Nypa fruticans) using CCA (Chromated Copper Boric Acid)
1999 - IRG/WP 99-40131
Golpata (Nypa fruticans) leaves provide a cheap but practical source of roof thatches. This study was carried out to determine whether the life span of Golpata could be extended by using CCB (Chromated Copper Boric Acid) treatment. Both leaves and midribs of Golpata , with different moisture contents ranging 16.63% to 70.67%, at the start of the experiment were treated with four different concentrations of CCB for 2, 4, 6 and 8 hours by dipping method. The treated samples were analyzed for chemical penetration and retention. Penetration was measured with a copper and boron indicator whilst retention was determined by X-ray spectroscopy. Results showed that moisture content had no significant effect for treating Golpata, but both chemical concentration and duration of dipping period have considerable effect on the preservation of Golpata. Better retention was exhibited by 6 hours of dipping time. Statistical analysis showed at 5% level of significance (confidence) that the effect of treatment times were also significant. Chemical concentration shows a significant effect on penetration of Golpata leaves but concentration has no effect on the retention. At 1% level of confidence, it is seen that the effect of chemical concentration, moisture content and their interaction on the penetration is not significant. For midribs it was found that the treatment time, different moisture content, chemical concentration and their interaction had no statistically significant effect at 1% confidence level on the increase of retention.
G N M Ilias, F Abdullah, M O Hannan, S M Feroz
Development of a model system to assess the efficacy and environmental impact of a chromated fluoride remedial treatment for creosoted distribution poles
1992 - IRG/WP 92-2395
A closed model system was designed to facilitate a controlled study of the leachability and environmental fate of a remedial preservative under laboratory conditions. The elements of the model include a precipitation apparatus above a treated pole section which is positioned in a representative soil profile supporting a sward of perennial ryegrass. The model will allow detailed examination of the movement of any toxic preservative constituents, in soil and water, released by an accelerated regime of simulated rainfall. Chemical analysis of soil and leachate will be complimented by plant analysis to identify bioaccumulation of any soil contaminants leached from the treated pole section. This paper details the design and development of the system from earlier environmental models, the difficulties encountered in construction and the sampling regimes to be employed. The benefits of such a system for inclusion in preservative testing protocols is discussed.
D C R Sinclair, G M Smith, A Bruce, B King
Preservative treatment of two bamboo species Borak (Bambusa balcooa Roxb) and Talla (Bambusa tulda Roxb) by Boucherie method
2003 - IRG/WP 03-40262
Bamboo is widely used as a construction material in rural and urban areas of Bangladesh. It is perishable in nature and highly susceptible to the attack of borer, termites and fungi. As a result, bamboo products do not last long. This short life of bamboo is increasing demand thereby increasing pressure on our homestead and natural reserve of bamboo. For this reason, it is needed to make the bamboo more durable by treating it with more simple and easy method with more effective preserving chemicals. Preservation of two bamboo species namely - borak (Bambusa balcooa Roxb.) and talla (Bambusa tulda Roxb.) has been carried out by Boucherie method with CCB (Chromated-Copper-Boron) chemicals. It has been observed that, talla can be easily treated than borak by this method. It has also been observed that total treating time varies with species, amount of pressure applied and the length of the bamboo species. The penetration of preservative throughout the bamboo is more or less similar for both the species.
M N Islam, A S M A Huda, A K Saha, S M Mithue
Performance of Paraserianthus falcataria treated with ACZA, ACQ, CC or CCA and exposed in Krishnapatnam harbour, India
2005 - IRG/WP 05-30382
Paraserianthus falcataria (=Albizia falcataria) treated to two retentions with ammoniacal copper zinc arsenate (ACZA), ammoniacal copper quaternary (ACQ), ammoniacal copper citrate (CC) and chromated copper arsenate (CCA) was assessed over 34 months in a tropical marine waters at Krishnapatnam harbour on the east coast of India. ACZA treatment showed comparatively better resistance than CCA, ACQ and CC, while CC provided the least resistance to marine borer attack. Eight species of borers i.e. Martesia striata, M. nairi, Teredo furcifera,T. parksi, Lyrodus pedicellatus, Nausitora hedleyi, Bankia campanellata and B. rochi were recorded on test panels. Of these, M. striata, L. pedicellatus, T. furcifera and B. campanellata were the dominant species, while other species settled sporadically. The results suggest that copper based preservatives are less likely to perform well under extreme tropical exposures without arsenic.
B Tarakanadha, K S Rao, J J Morrell
Fundamentals on steam fixation of chromated wood preservatives
1988 - IRG/WP 3483
Weathering of treated wood directly after impregnation leaches up to 2% of copper-chromate-containing wood preservatives. Almost total fixation of Cr+6 is achieved by steaming the treated wood at 100°C to 120°C, preferably 110°C. To initiate such spontaneous fixation 85°C to 90°C inside the wood are essential, which requires heating times ranging from 20 to 80 min, depending on timber species, retention, required depth of fixation, and steaming conditions. Lower temperatures without steam cause an increased leaching, due to drying effect without promotion of fixation. For softwoods the efficacy of the preservative is not effected; in the case of hardwoods treated with CCA, a certain reduction against softrot fungi was noticed. Both bending and compression strength of pine and spruce remained unchanged. A carefully performed steam fixation will effectively reduce pollution.
R-D Peek, H Willeitner
Laboratory studies of CCA-C-leaching: influence of wood and soil properties on extent of arsenic and copper depletion
2002 - IRG/WP 02-50186
The extent which a wood preservative leaches is important for efficacy studies and environmental concerns. However, little information exists on the effect soil properties have on leaching. This study investigated leaching of stakelets which had been cut from five different southern yellow pine (SYP) sapwood boards then treated with CCA-C to a target retention of 6.4 kgm-3 (0.4 pcf). All stakelets were leached for 12 weeks by a common laboratory method in five different soils or water, with five replicate stakelets per board/soil. The physical and chemical properties of the five different soils were determined and the average leaching of the individual components of CCA was correlated with the various soil properties. Unfortunately, migration of a soil component (likely iron) into the stakelets from at least one of the five soils interfered with Cr determination by X-ray fluorescence; consequently, Cr depletion was not studied. Stakelets cut from one board tended to have lower Cu and As losses than the average of the other four boards for all five soils and water, and stakelets from another board tended to have higher Cu losses. Stakelets from all five boards had similar initial Cu and As levels, suggesting that the board effect was not due to differences in initial retentions. Cu loss was approximately equal to or greater than As loss for stakelets exposed to all five soils, but for wood leached in water the As loss was about twice the Cu loss. The soil property which was most statistically correlated to Cu loss was % Base Saturation (r2 of 77%), with Soil Acidity (pH) also important as a single predictor, and the Cr and Cu Soil Contents important as secondary predictors. The relationship between % Base Saturation (or Soil Acidity) and % Cu leached was not linear, however. A negative correlation was observed between Soil Cu Content and the metal leached from wood. The best factor to predict As loss was the Soil Cu Content, with Exchangeable K and % Silt also contributing to give an overall r2 of 72.3%. The % Organic Matter and the Soil As Content were also important as secondary predictors. We conclude that depletion of CCA is extremely complex and that Cu and As depletion appears to be influenced differently by the soil properties. Furthermore, extent of leaching can vary between different wood samples of the same species and even samples cut from the same board; thus, leaching data are not precise. Recommendations are given for a standard laboratory method for ground-contact leaching.
D Crawford, R F Fox, D P Kamden, S T Lebow, D D Nicholas, D Pettry, T Schultz, L Sites, R J Ziobro
Water repellency of wood treated with alkylammonium compounds and chromated copper arsenate
2000 - IRG/WP 00-30231
The comparative water sorption properties of southern pine treated with CCA and several alkylammonium compounds was evaluated for freshly treated wood and for wood after exposure in a fungus cellar. It was found that CCA imparts considerable water repellency to wood which is reduced somewhat after exposure to wet soil. With the exception of a long chain (C20 -C22) compound, the alkylammonium compound treated wood exhibited an increased water sorption rate and also exhibited increased total swelling.
D D Nicholas, A Kabir, A D Williams, A F Preston
Rapid fixation of Chromated Copper Arsenate (CCA) wood preservatives by microwave treatment
2000 - IRG/WP 00-40184
Rapid microwave heating of freshly chromated copper arsenate (CCA) treated timber indicates that rapid preservative fixation is possible within approximately 40 seconds. The leaching of CCA was evaluated using simulated rainfall. Cost analyses indicates that microwave fixation using an on-line conveyor belt fixation process with an output of 4m3/hour using a microwave power supply of 230 kW costs approximately AU$ 16/m3 for electricity costs of AU$ 0.077/kW-h. When electricity cost are AUS$ 0.017/kW-h the treatment costs are reduced to AU$ 10/m3.
G Torgovnikov, P Vinden, E Mapanda, P R S Cobham
Studies of the mechanism of chromated-copper preservative. Fixation using electron spin resonance
1992 - IRG/WP 92-3701
Two softwoods and one hardwood species were treated with chromium trioxide, copper sulphate, chromated-copper wood preservative (CCA). The treated wood samples were analyzed during fixation by electron spin resonance (ESR). ESR spectra indicated that more than one Cr(V) species was generated from Cr(VI) soon after CCA treatment. The Cr(V) signal became strong within increased several hours followed by the gradual decay of Cr(V) accompanying with generation of single broad Cr(III) species. Cr(V) signal still remained at least up to six months after the treatment. ESR spectral parameters from Cu(II) signal consisted of a quadruplet at lower field with a unresolved absorption of higher field, suggesting a evidence of a dX²-Y² ground state of Cu2+ ions bound in inner-sphare complexes with "O4" ("O6") ligands arranged in square planar cordination (distorted octahedral) cordination. Cu(II) signal did not change significantly during fixation.
K Yamamoto, J N R Ruddick
Chromated copper arsenate preservative treatment of hardwoods. Part 2: leaching performance of seven North American hardwoods
1997 - IRG/WP 97-30132
Seven North American hardwood species were treated with 2% CCA-C solution and fixed at temperatures of 21°C and 50°C and conditions of high relative humidity (95%) as described in Part 1 of this presentation. Red pine (Pinus resinosa) was included as a softwood for comparison. Adequately fixed wood blocks (99.9% chromium fixation) were exposed to leaching tests according to AWPA E11-87 test. Particularly high leaching losses were determined for red oak, red maple and beech.. In the case of red oak all three elements were leached in high quantities, while from red maple and beech higher arsenic leaching occurred. Higher leaching of arsenic was observed in those red maple blocks that fixed the fastest. Leaching losses from aspen, basswood and yellow poplar were low and comparable for both fixation temperatures. Very low leaching of arsenic from aspen and yellow poplar was observed in all series of experiments. Leaching results obtained confirmed the validity of the division of the examined hardwoods into three groups according to the CCA fixation and leaching results: fast fixing/high leaching group (beech, red oak and red maple), intermediate fixation rate and leaching amount (white birch and red pine) and slow fixing and low leaching group (aspen, yellow poplar and basswood).
T Stevanovic-Janezic, P A Cooper, Y T Ung
Properties of particleboard made from recycled CCA-treated wood
2000 - IRG/WP 00-50146
Recovery of chromated copper arsenate (CCA)-treated wood for reuse ha s been the focus of several international research groups due to the imminent disposal problem created when large quantities of CCA-treated wood ultimately come out of service. Bioleaching with Bacillus licheniformis CC01 and oxalic acid extraction are two methods known to remove significant quantities of metals from CCA-treated wood. Remediated particulate CCA-treated southern pine was reassembled into particleboard (PB) using 10% urea-formaldehyde resin. Particleboard panels were evaluated for internal bond (IB), modulus of elasticity (MOE), modulus of rupture (MOR), thickness swell (TS) and water absorption compared to particleboard manufactured from virgin southern pine and CCA-treated southern pine. Particleboard panels prepared from the remediated chips showed an average 28% reduction in IB and a 13% reduction in MOR compared to values for PB prepared with virgin chips under the pressing parameters used in this study, though individual IB values for all specimens were above the ANSI standard for medium density particleboard. An 8% increase in MOE in the remediated chip PB compared to the virgin chip PB may indicate densification of the fiber surface as a result of the acid extraction step of the remediation process. Thickness swell and water absorption after 24-hour submersion also increased in PB prepared from remediated chips (15% and 14%, respectively). We conclude that pressing parameter optimization could alleviate decreases in MOR and IB seen in PB made from remediated chips, and that the effects of acid extraction on MOR and IB properties should be further evaluated.
C A Clausen, S N Kartal, J H Muehl
Management strategies for the disposal of CCA-treated wood
2000 - IRG/WP 00-50155
A two-fold management strategy is presented for the disposal of wood treated with chromated copper arsenate (CCA). The first part focuses on the use of alternative wood treatment preservatives. The second part of the management strategy addresses short-term disposal issues (less than 25 years) by developing new methods to handle the waste. A set of seven alternative wood preservatives were evaluated through this study. Issues evaluated included efficacy, depletion, corrosion, and costs. Results indicate that viable alternatives are available for CCA-treated wood for the lower retention levels (4 to 6.4 kg/m3). The development of disposal-end management strategies for CCA-treated wood began by tracking the discarded wood within the disposal sector of the State of Florida, USA. It was found that existing disposal methods, which included disposal within unlined landfills and recycling either as mulch or wood fuel, were not acceptable. New disposal-end management strategies evaluated included treatment methods for CCA-treated wood ash and two sorting technologies for separating CCA-treated wood from other wood types within the disposal stream. Results indicate that citric acid is effective at removing arsenic from CCA-treated wood ash. Chemical stain and x-ray based methods were found suitable for sorting treated from untreated wood.
H M Solo-Gabriele, T G Townsend