Your search resulted in 70 documents. Displaying 25 entries per page.
Remediation of pentachlorophenol- and creosote-contaminated soils using wood-degrading fungi
1994 - IRG/WP 94-50021
Microbiological treatment of hazardous wastes has generally been associated with the use of bacteria. During the past decade a significant body of evidence has accumulated that demonstrates that fungi, in particular white-rot fungi, have the ability to degrade a wide range of hazardous organic compounds (xenobiotics) and thus might also be useful for treatment of materials contaminated with these compounds. Our work has focused on the development of a soil remediation technology that is based on the xenobiotic-degrading abilities of these fungi. This work has demonstrated that the technology is useful for remediation of pentachlorophenol-contaminated soils and may also be useful for creosote-contaminated soils. In this presentation the fungi and their xenobiotic-degrading abilities will be described and a summary of applications of this technology to remediation of PCP and creosote-contaminated sites and a discussion of technological developments necessary for commercialization of the technology will be given.
R T Lamar, T K Kirk
Optimisation of an analytical method for the determination of total fluoride in preservative-contaminated soils using water steam distillation and an ion-selective electrode
1999 - IRG/WP 99-20153
This paper describes a simple modified procedure for the quantitative fluoride determination of different origin in a soil matrix using a water steam distillation and an ion-selective electrode. Distillation methods generally require a preliminary preparation step like fusing. The modified method presented here is based on the direct distillation of fluoride so that no further sample preparation is necessary. The separation is carried out in a perchloric acid medium and the analysis takes place by means of a reduced Total Ionic Adjustment Buffer (TISAB) solution. This technique allows also the application of a battery equipment, i. e. simultaneous distillation will be possible. Using a 2-flask system approximately 10 soil samples with two parallels can be analysed per day. The adaptation of the test method, possible checked parameters of influence, the obtained results and observed problems are discussed. The results showed that in general satisfying (>90%) recovery rates can be received.
Wood preservation sites polluted by CCA. Is potassium diphosphate incubation a catalyst for the electrodialytic remediation of these soils?
1998 - IRG/WP 98-50106
As part of an evaluation of a newly developed electrodialytic soil remediation technique, we investigated the incubation of a contaminated soil (from a Portuguese wood preservation site polluted with CCA) with potassium diphosphate as a possible catalyst for the removal of heavy metals and metalloids. A chemical sequential extraction scheme (SE) applied to the soil has shown that the potassium diphosphate (0.1 M), used for the attack of forms organically bound, extracted 30% of Cu, 15% of Cr and 23% of As. Two electrodialytic laboratory experiments (E and O) were carried out for 35 days in a laboratory cell, with a current density of 0.2 mA/cm2. In Exp. E the contaminated soil was put in the cell as it was sampled, and in Exp. O, the soil was previously incubated with 0.1 M K4P2O7, for 51 h. The aim was to compare results of process efficiencies by maintaining either acid or basic pH conditions in the soil, both media known to keep solubilization of metals high. Results show that the remediation process was not more efficient in the soil submitted to the pre-treatment, for the considered time length, as total Cu, Cr and Zn soil concentrations were higher after Exp. O than after Exp. E. The K4P2O7 incubation did not succeed in maintaining a basic pH in the soil. However, the soil SE results show that Exp. O put more Cu, Cr and Zn in "soluble and exchangeable forms" than Exp. E. If the process had been run for a longer period, electromigration could have acted more efficiently and these elements are expected to be removed from the soil, increasing the overall efficiency of the process. Addition of extra alkali could have furthered the process.
A B Ribeiro, G Bech-Nielsen, A Villumsen, A Réfega, J Vieira e Silva
Leaching Potential of selected Mississippi Soils Contaminated with Pentachlorophenol (PCP) and Chromated Copper Arsenic (CCA)
2013 - IRG/WP 13-50293
Desorption of pentachlorophenol (PCP), and chromated copper arsenic (CCA) from five Mississippi soil regions was studied. The soils tested were Blackland Prairie (Dorman), the Interior Flatwoods (Winston), the Delta, the Coastal Plains (Wiggins) and the Loess soil (Raymond). Soils were contaminated with 500 ppm and 1000ppm PCP and 1000 ppm for CCA respectively. Toxicity Characteristic Leaching Procedure (TCLP) results revealed that the Wiggins soil desorption level for 500 and 1000 ppm PCP contaminated soils was significantly higher than other soil types. Dorman and Raymond soils leached the most copper and chromium. Dorman soil leached the highest arsenic level among CCA treated soils, while Winston soil consistently leached the least concentration of these metals.
K Ragon, H Borazjani, S Keshani Langroodi, S Diehl
Danish wood preservatives approval system with special focus on assessment of the environmental risks associated with industrial wood preservatives
2001 - IRG/WP 01-50166-01
The following is a description of the procedure used by the Danish Environmental Protection Agency to assess the environmental risks associated with preservatives used in the pressure impregnation of wood. The risk assessment covers issues considered to be of significance for the environment and which are adequately documented so as to allow an assessment. Such issues are persistence and mobility in soils, bioaccumulation and the impact on aquatic and terrestrial organisms. Unless required in special circumstances, the assessment does not apply to birds and mammals as the normal use of preservative treated wood is not expected to involve any noteworthy exposure of these groups. Approval of wood preservatives will be based on a general assessment of the environmental risk associated with the normal use of wood treated with the preservative in a realistic worst case situation. The assessment may address other aspects such as disposal and total life cycle.
Confocal laser scanning microscopy of a novel decay in preservative treated radiata pine in wet acidic soils
1997 - IRG/WP 97-10215
Light microscopy of radiata pine (Pinus radiata D. Don) field test stakes (20x20x500mm3) exposed in wet acidic (pH 3-4) soil for 12 - 24 months showed predominance of an unusual type of decay characte-rised by tunnelling attack of wood cell walls. After two years decay was moderate to severe in wood treated to ground contact CCA specifications and also equivalent retentions of creosote, and a number of new generation preservatives. Relative to other New Zealand temperate test sites and also an Australian tropical site, the New Zealand acidic soil test site was very aggressive. Correlative scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to elucidate the micromorphology of this attack. Tunnels of diameter 0.2-5 µm were present throughout all layers of the cell wall, and their orientation was not related to cellulose microfibril orientation. They also showed no preference for particular cell wall layers, indicating a lignin degrading capability. CLSM images showed that living, connecting fungal hyphae were present in the cell lumina and tunnels. This type of attack was predominant in wood that was highly saturated with water whereas wood that was less moist was predominantly attacked by classical white rot. Ongoing isolation and incubation studies in conjunction with further microscopy should enable identification of the fungal species involved.
R N Wakeling, Ying Xiao, A P Singh
A comparison of soft rot, white rot and brown rot in CCA, CCP, CCF, CCB, TCMTB and benzalkonium chloride treated Pinus radiata IUFRO stakes, after 9-15 years exposure at five test sites in New Zealand
1991 - IRG/WP 1485
The aim of this study was to determine if decay type varies significantly between five field trial test sites of different soil type, aspect and climate in 9-15 year old, replicate CCA, CCF, CCP. CCB, TCMTB and AAC treated IUFRO stakes. A visual on-site assessment of decay type on every test stake was made and observations confirmed by microscopical examination. Regression analyses were used to determine significant differences of percentage frequency of occurrence of each rot type between sites and preservatives. Large differences in percentage frequency of occurrence of rot type were evident between sites. One site was dominated by brown rot (85%) and two were dominated by soft rot (99 and 91%). The fourth site had intermediate proportions of brown rot (40%) and soft rot (71%) but had the second highest occurrence of white rot (32%) (highest = 37%; lowest = 11%). The fifth site was distinct in that a large proportion of stakes (69%) had both well established brown rot and soft rot. Stakes at the other four sites tended to have only one rot type. Some highly significant preservative effects were also found. Possible causes of these differences are discussed in terms of inter-site soil type, climate and other differences.
R N Wakeling
Soil virulence tests using Scots pine sapwood
1973 - IRG/WP 222
Following the tests reported in Document No: IRG/WP/210, in which soils from different laboratories were investigated for virulence, supplementary tests have been carried out using Scots pine sapwood and an extended incubation period.
J K Carey, J G Savory
Collaborative soft rot tests: Programme and test method
1973 - IRG/WP 229
J G Savory, J K Carey
Agenda:Workshop CCA failures in horticultural soils
1983 - IRG/WP 3241
J A Butcher, H Greaves
Collaborative soft rot tests: Results of analyses of soil samples
1976 - IRG/WP 263
C R Levy
Bacteria and wood. A review of the literature relating to the presence, action and interaction of bacteria in wood
1971 - IRG/WP 101
S E Rossell, E G M Abbot, J F Levy
Testing wood in ground contact: An artificial soil
1977 - IRG/WP 280
This document is an interim report on the development of the artificial soil medium. It includes some information on the relationship between soil, wood and water which is of relevance in testing.
E F Baines, D J Dickinson, J F Levy
Cu, Cr and As distribution in soils adjacent to CCA treated utility poles in Eastern Black Sea Region of Turkey
2004 - IRG/WP 04-50214
In this study, the main objective was to asses the distribution of Cu, Cr, and As in soils adjacent to CCA treated utility poles in Eastern Blacksea Region of Turkey (Trabzon, Rize and Artvin ) and determine the influence of soil composition. Surface (0-5cm), subsurface soil samples (30-40cm) were collected near CCA-treated utility poles and control soil samples away from CCA-treated utility poles were also collected. Water holding capacity, pH, mechanical properties of soil samples were determined for both depth levels. Results showed that Cu, Cr and As concentration in soil samples taken from all three cities in 0-5cm depth was higher than soil samples taken from 30-40cm depth. Cu, Cr and As concentrations were much higher in soil samples taken from city of Rize.
E D Gezer, Ü C Yildiz, A Temiz, S Yildiz, E Dizman
Factors affecting leaching of preservatives in practice
1978 - IRG/WP 3113
At the 7th Meeting of the IRG in Poland in May 1975, the findings of collaborative laboratory leaching techniques were discussed, and the dangers inherent in using such results to predict the behaviour of preservative-treated components in service were emphasised. In order to improve our understanding of the factors governing leaching of preservatives in practice, and to identify areas where further research is required, it was agreed that a literature review should be prepared. This is presented below. Some points may be made regarding its format and content. First, the review shows that a large number of factors are of importance, including the properties of the wood, the leach water, the preservative and method of application and the nature of the environment to which the product is exposed. In many situations these factors interact and it is clearly impossible within the scope of this short paper to discuss all aspects of the problem in detail. However, the compilation of references will give ready access to the literature on particular topics. For ease of collation, the findings are discussed under a number of different headings. Secondly, less than one-third of the references cited deal with the results of service or field trials, while the others describe laboratory experiments designed to provide comparative data. The reservations expressed above concerning such small-scale experiments must be borne in mind when considering the validity of these findings. The information available on this topic up till 1964 was comprehensively reviewed by Wallace who identified and commented upon many of the factors discussed below. Her paper contained discussion on the performance of individual preservatives and on the mechanism of their fixation within the wood. These topics will not be considered here in any detail except insofar as they reflect general trends.
R Cockcroft, R A Laidlaw
Nitrogen content of soils at field sites
1981 - IRG/WP 1133
Nine participants in the Collaborative Field Experiment submitted samples for nitrogen analysis to this laboratory as requested by Leightley (IRG/WP/3162). These arrived in a variety of conditions e.g. wet, dried, sterilised and unsterilised and sometimes spent a considerable time in transit. Soils varied in cellular fraction organic matter content, some were obviously sieved prior to postage while others contained significant quantities of large vegetative detritus. Samples were also taken at different times of the year and seasonal and climatic factors may have influenced the values subsequently obtained by analysis.
B King, G Mowe
Laboratory investigations about the mobility of some inorganic wood preservatives in soils
1998 - IRG/WP 98-50101-22
Wood preservatives and components of wood preservatives leached from impregnated wood can enter the soil and thus contribute to the pollution of the groundwater. However, there is lack of understanding concerning the interacting parameters of wood preservative, leachate, soil and soil solution. To characterise of the behaviour of active ingredients and for the assessment of their environmental impact, leaching and diffusion processes are of basic interest with which the concentration of the relevant ions in the soil solution is determined by the reactivity of the ion, and by the type of linkage between the ion and the soil. The concentration and the specific behaviour of the ions in the solid and liquid phases can be investigated using different methods, e. g. using soil column tests (lysimeter). Several designs of lysimeter have been tested with water-soluble wood preservatives and the results been compared with the behaviour of wood preservative components leached from impregnated wood. As a result of the variability of the experimental set-up, of the wood preservatives and of the different soils tested, it became obvious that a standard procedure has to be developed. By means of some examples of varying results the similarities and differences of different procedures are discussed.
E Melcher, R-D Peek
Antagonistic effect of Trichoderma spp. against Serpula lacrymans in the soil treatment test
1991 - IRG/WP 1473
Soil treatment tests for preventing growth of Serpula lacrymans were conducted using Trichoderma spp. as antagonists. Soil specimens tested were Kanuma-soil without organic matter and the horticultural soil which was collected from the test site of the stake test. Perfect efficacy of treatment with Trichoderma spp. was shown when the horticultural soil without sterilization was used as a soil specimen.
S Doi, A Yamada
Collaborative soft rot experiments 1974. Preliminary analysis of results
1975 - IRG/WP 251
J K Carey, J G Savory
Proposal for further work on environmental questions
1988 - IRG/WP 3494
Although very much is known about the environmental and health and safety aspects on various wood preservatives and treated wood knowledge is still lacking on some important issues. Some examples are: - The fate of wood preservatives in the environment, eg by leaching from treated wood and contaminated soil; - How big is the "problem" of pollution, etc from the wood preserving industry in comparison with that from other sources? - What are the consequences of using alternative materials when particular attention is paid to the environment, health and safety, service life, etc? We propose that the "Health and safety aspects" Sub-group identifies the most important problems regarding the environment, health and safety and that an action plan for further work is presented at the next meeting.
J Jermer, M-L Edlund
Comparison of the effect of different soil sources on the type and rate of decay of CCA-treated pine exposed in a soil-bed
1984 - IRG/WP 2213
The types of decay observed in CCA-treated pine posts in horticultural situations in New Zealand can be reproduced using a soil-bed exposure. Radiata pine stakelets, untreated or treated to 1.4, 2.7, or 5.4 kg/m³ with Tanalith NCA, were exposed to six different soil sources. The local nursery soil used for all standard laboratory tests was found to represent the greatest decay hazard to untreated pine. Poverty Bay horticultural soils were more hazardous than the local field test site soil to CCA-treated pine. Soil collected from adjacent to a 'decaying' post could decay treated wood faster than soil collected from around a 'sound' post. Brownrot, softrot, and bacterial degrade was observed. All failures of untreated pine and early failures of CCA-treated pine were caused by brownrot.
J A Drysdale
Review of remediation methods of sites contaminated by wood preservatives - testing of filter material for use in permeable barrier technology
1999 - IRG/WP 99-50141
Several treatment methods are currently available for treatment of contaminated sites. Soil and water can be treated by immobilisation, separation or destruction of contaminants. It has been common to use intensive treatment methods starting with soil excavation to reach strict purification goals. However, technical and financial reasons make it difficult to reach the desired treatment criteria. As a result, alternative treatment methods are now being allowed. Less intensive in situ methods are being developed, such as natural attenuation, phytoremediation and permeable barriers. A permeable barrier is a passive treatment method for contaminated groundwater. A study was conducted to test various barrier materials for filtering creosote contaminated groundwater. Peat, compost, bark, sewage sludge and sewage sludge pellets were tested out for sorption of phenol, 2-methylphenol and 2,4-dimethylphenol. Peat and compost showed best sorption efficiency. Peat and compost were mixed with sand in various fractions to see if sand can be used to improve hydraulic properties of the filter material.
G Rasmussen, H Iversen, S Andersen
A contribution to the adsorption/desorption behaviour of zinc-hexa-fluoro-silicate in different soils
1995 - IRG/WP 95-50056
The estimation of a possible endangering of the groundwater through wood preservatives and thereof deriving measures for the avoidance of secondary damages require among others exact knowledge concerning the behaviour of wood preservative compounds in the soil matrix. Adsorption and desorption behaviour were determined at four soils of different characteristics, which were brought in contact with aqueous solutions of zinc-hexa-fluoro-silicate. For the respective experiments four concentrations were prepared containing 10, 50, 100 and 250 ppm zinc ions. Water of p.a. quality served as reference. As to be expected the soils in question behaved different: the adsorption of inserted ions increased with increasing clay content of the soil. On the other hand significant differences exist also with respect to the adsorption behaviour of the zinc cation in relation to the hexa-fluoro-silicate anion. Within the concentration interval investigated, the same soil adsorbed approximately the same proportional zinc quantity. However, when increasing the hexa-fluoro-silicate-ion concentration a proportional decrease concerning the degree of adsorption was observed. The results show that it is not possible to conclude from partial results achieved with individual preservative compounds to the overall system "wood preservative"-soil and that further investigations are necessary for an inclusive description of the problem.
E Melcher, R-D Peek
Decay types observed in small stakes of pine and Alstonia scholaris inserted in different types of unsterile soil
1990 - IRG/WP 1443
The attack of various wood-degrading microorganisms occurring in mini-stakes of pine and Alstonia scholaris buried in various types of unsterile soil was studied. Attacks by white rot, brown rot, soft rot, erosion bacteria, tunnelling bacteria and actinomycetes were found. Soft rot occurred in all soils, whereas attack by white rot and especially brown rot and erosion bacteria was rare. The type of soil influenced the occurrence of attack by tunnelling bacteria and actinomycetes. The former were mainly associated with horticultural soils whereas the latter were associated with soils from coniferous forests.
T Nilsson, G F Daniel
Soft rot decay of Eucalyptus maculata Hook. in different soils from Queensland, Australia
1980 - IRG/WP 1113
In the present work, different Queensland soils were chosen and their gross effects on the decay of treated and untreated Eucalyptus maculata examined. The soils were also amended with various levels of phosphate to study the response of the wood decay mycota to an increasing supply of this nutrient. Phosphate amendment was chosen because of the wide-scale use of superphosphate on Queensland soils and the importance of inorganic phosphate in the carbohydrate metabolism of microorganisms.
L E Leightley, I W Russell