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Large volumes of engineered wood products (EWPs) and paper are routinely placed in landfills in Australia, where they are assumed to decay. However, the extent of decay for EWPs is not well-known. This study reports carbon loss from EWPs and paper buried in landfills in Sydney, Brisbane and Cairns in Australia, located in temperate, subtropical and tropical climates, respectively. The influence of pulp type (mechanical and chemical) and landfill type (municipal solid waste - MSW and construction and demolition - CD) on decay levels were investigated. Carbon loss for EWPs ranged from 0.6 to 9.0%; though there is some uncertainty in these values due to limitations associated with sourcing appropriate controls. Carbon loss for paper products ranged from 0 to 58.9%. Papers produced from predominantly mechanical pulps generally had lower levels of decay than those produced via chemical or partly chemical processes. Typically, decay levels for paper products were highest for the tropical Cairns landfill, suggesting that climate may be a significant factor to be considered when estimating emissions from paper in landfills. For EWPs, regardless of the landfill type and climate, carbon losses were low, confirming results from previous laboratory studies. Lower carbon losses were observed for EWP and paper excavated from the Sydney CD landfill, compared with the Sydney MSW landfill, confirming the hypothesis that conditions in CD landfills are less favourable for decay. These results have implications for greenhouse gas inventory estimations, as carbon losses for EWPs were lower than the commonly assumed values of 23% (US EPA) and 50% (Intergovernmental Panel on Climate Change). For paper types, we suggest that separate decay factors should be used for papers dominated by mechanical pulp and those produced from mostly chemical pulps, and also for papers buried in tropical or more temperate climates.

Several alkaline wastes are likely to pose a threat to the ambient environment due to their high alkalinity and fine particles, if disposed improperly. These alkaline wastes include paper pulp and mill waste (lime mud), bauxite mining residue (red mud ), and cement and demolition wastes. In this chapter, the characteristics of these alkaline solid wastes from paper industry, construction, and mining process are discussed. In addition, the situations and challenges in conventional utilization of the alkaline wastes are illustrated. After appropriate treatment or activation processes, the solid wastes can be utilized in various novel approaches, such as coagulant and adsorbent for water purification process.

Searching for best stabilizer to overcome the problems in the place of Expansive soils are being a main concern still, not only to achieve the required soil’s engineering properties but also to meet the cost efficiency of the project undergone. The main objective of this paper was to review the materials and methods that have been adopted to stabilize the Expansive soil based on experimental studies. Investigation on various materials such as industrial granite waste, demolition waste and quarry dust and foundry waste sand. The effectiveness of these materials as soil stabilizer is observed with the experimental results only in terms of strength, based on California Bearing Ratio (CBR) tests and shear tests that have been conducted. The Engineering properties of the Expansive soil were increased comparatively and these materials have potential to be used as a soil stabilizer in construction practices and these are also economic.

Buildings consume a vast amount of energy during the life cycle stages of construction, use and demolition. Total life cycle energy use in a building consists of two components: embodied and operational energy. Embodied energy is expended in the processes of building material production, on-site delivery, construction, maintenance, renovation and final demolition. Operational energy is consumed in operating the buildings. Studies have revealed the growing significance of embodied energy inherent in buildings and have demonstrated its relationship to carbon emissions. Current interpretations of embodied energy are quite unclear and vary greatly, and embodied energy databases suffer from the problems of variation and incomparability. Parameters differ and cause significant variation in reported embodied energy figures. Studies either followed the international Life Cycle Assessment (LCA) standards or did not mention compliance with any standard. Literature states that the current LCA standards fail to provide complete guidance and do not address some important issues. It also recommends developing a set of standards to streamline the embodied energy calculation process. This paper discusses parameters causing problems in embodied energy data and identifies unresolved issues in current LCA standards. We also recommend an approach to derive guidelines that could be developed into a globally accepted protocol.

This document is the final version of a paper submitted to the Waste Management Symposia, Phoenix, 2010, abstract BJC/OR-3280. The primary document from which this paper was condensed is In-Situ Measurement of Low Enrichment Uranium Holdup in Process Gas Piping at K-25 Using NaI/HMS4 Gamma Detection Systems, BJC/OR-3355. This work explores the sufficiency and limitations of the Holdup Measurement System 4 (HJVIS4) software algorithms applied to measurements of low enriched uranium holdup in gaseous diffusion process gas piping. HMS4 has been used extensively during the decommissioning and demolition project of the K-25 building for U-235 holdup quantification. The HMS4 software is an integral part of one of the primary nondestructive assay (NDA) systems which was successfully tested and qualified for holdup deposit quantification in the process gas piping of the K-25 building. The initial qualification focused on the measurement of highly enriched UO{sub 2}F{sub 2} deposits. The purpose of this work was to determine if that qualification could be extended to include the quantification of holdup in UO{sub 2}F{sub 2} deposits of lower enrichment. Sample field data are presented to provide evidence in support of the theoretical foundation. The HMS4 algorithms were investigated in detail and found to sufficiently compensate for UO{sub 2}F{sub 2} source self-attenuation effects, over the range of expected enrichment (4-40%), in the North and East Wings of the K-25 building. The limitations of the HMS4 algorithms were explored for a described set of conditions with respect to area source measurements of low enriched UO{sub 2}F{sub 2} deposits when used in conjunction with a 1 inch by 1/2 inch sodium iodide (NaI) scintillation detector. The theoretical limitations of HMS4, based on the expected conditions in the process gas system of the K-25 building, are related back to the required data quality objectives (DQO) for the NBA measurement system established for the K-25 demolition project. The combined review of the HMS software algorithms and supporting field measurements lead to the conclusion that the majority of process gas pipe measurements are adequately corrected for source self-attenuation using HMS4. While there will be instances where the UO{sub 2}F{sub 2} holdup mass presents an infinitely thick deposit to the NaI-HMS4 system these situations are expected to be infrequent. This work confirms that the HMS4 system can quantify UO{sub 2}F{sub 2} holdup, in its current configuration (deposition, enrichment, and geometry), below the DQO levels for the K-25 building decommissioning and demolition project. For an area measurement of process gas pipe in the K-25 building, if an infinitely thick UO{sub 2}F{sub 2} deposit is identified in the range of enrichment of {approx}4-40%, the holdup quantity exceeds the corresponding DQO established for the K-25 building demolition project.

The City of Cape Town has recently drafted an energy strategy and an integrated waste management plan. The creative implementation of these strategies requires knowledge of potential sources of energy and flows of waste. Inventories of requisite data are sparse. Wood and paper are interesting cases in point, as they are significant contributors to waste and potential energy carriers. A better knowledge of all related flows is obtained by means of a Material Flow Analysis (MFA). Data have been gathered for the fuel wood sector, the manufacturing, construction and demolition sector, the pulp and paper market, the municipal solid waste sector and the wastewater sector. Analysis shows that ∼70% of the renewable energy target of the City (10% of energy demand to be covered by renewables by 2020) could be met via the redirection of woody material flows within the Cape Metropolitan Area and the utilisation of innovative transformation technology.

Accounting for emissions associated with the demolition of buildings can help reduce the environmental footprint of the structures.

With the development of the urbanization and demolition in recent years in China, the amount of construction and demolition waste has annually increased rapidly. In consideration of the successful application of construction and demolition waste, this study aims to enhance the content of recycled aggregate and evaluate the performances of cement stabilized mixture with recycled aggregate from construction and demolition waste. Two types of recycled aggregates based on two processing techniques, stationary processing, large-scale processing, and four contents (20%, 30%, 50%, and 100%) were selected. The performances of cement stabilized mixture with recycled aggregate were evaluated through mechanical performance test, freeze–thaw test, scour test, drying shrinkage test and fatigue performance test. The results indicated that the large-scale processing technology was helpful to improve the content of recycled aggregate. Under the premise of the same mixture composition, the unconfined compressive strength, indirect tensile strength, and compression modulus of resilience exhibited non-linear increase with age. With the increase in the amount of construction waste recycled materials, the frost resistance of cement stabilized recycled mixtures weakened. The large-scale processing technology was helpful to improve the content of the recycled aggregate, benefit to reduce the shrinkage coefficients, and slightly enhanced the anti-scouring ability of the mixture. The cement stabilized recycled aggregate mixture with recycled aggregate had lower mechanical sensitivity than that of the mixture without recycled aggregate, while the mechanical sensitivity increased with the increase of the recycled aggregate.

In the case of an uncontrolled demolition or a terrorist attack no prior knowledge is usually available as to what the exact explosives is and what the exact charge weight is. As well, in most cases the authorities have no idea what the target is to be in advance of an attack. For a designer to design a structure to minimize the damage in such cases is somewhat difficult if not impossible but, nevertheless, it must be done. Once the explosive, either as an improvised explosive device or vehicle improvised explosive device, has detonated the normal aftermath of such events such as fragmentation, primary and secondary fires, ground cratering and building collapse are all obvious. From a designers’ point of view, the starting point is to understand in detail all building collapse mechanisms to be able to design for such events and so allow time, if possible, for all those caught inside a building to escape and for structural damage to be minimized. To obtain such design parameters the designer must refer to past uncontrolled demolitions on Australian soil or in countries close by to gauge the most likely threat. Prior to design commencing one also must have clear criteria and strategy in mind to be able to complete a suitable design to ensure his obligation to allow time for people to escape from its collapse is met and damage is minimized. Designers not only have to address new building designs to withstand blast and ballistic loadings but also how to retrofit existing buildings cost effectively against such blast and ballistic loadings. Detailed lists of required criteria and strategies that are necessary so at to arrive at a suitable design for any blast or ballistic loadings likely to being applied to a structure are provided within the paper based on all aspects of an uncontrolled demolition (explosion) that may confront a designer.

Use of water-borne wood preservatives began in approximately the 1950s. Residential and commercial uses rapidly developed for products such as decking, fences, and other outdoor structures. Nearly all such products were treated by preservatives using arsenic as a major ingredient. The most common preservative was chromated copper arsenate (CCA). A smaller volume used ammoniacal copper zinc arsenate (ACZA). Preservative label changes made in 2003 limited uses of these arsenical treatments to industrial or agricultural type uses, such as poles, piles, ties, bridges, and fencing. Use volumes of preservative-treated wood continued to grow after the label change, but the types of preservatives used changed greatly. The amounts of water-borne treated wood reaching end-of-life and being disposed also continued to grow, reflecting the increasing inventory of volume in service. However, the volume of arsenical-treated wood being disposed peaked in approximately 2008 and is now only approximately one-quarter of that volume. Most of the arsenical-treated wood now being disposed consists of large, easily identified and separated pieces, such as round poles, piles, and fence posts and timbers, which can be easily managed separated from other wood construction and demolition (C & D) waste. Thus, managing C & D waste to limit arsenic contamination of potential products, such as mulch, will be much more practical than some have feared.