Issue 11 2012
SPECIAL EDITION: LANDFILLS BUMPER ISSUE
Landfills and energy Sampling and Groundwater production analysis plans remediation Cleaning up to produce energy A crucial first step Hobart zinc smelter case study uncertainty inriskassessment,andcleaningup. challenges ofbestpracticepolicy, bettermeasurement, minimising agency partners,CRCCARE’s research program focusesonthe and air. Withauniquemixofindustry, universityandgovernment assessing, preventing andremediating contaminationofsoil,water CRC CAREisAustralia’s leadingscience-basedpartnershipin Cooperative Research Centre forContamination Assessment andRemediationoftheEnvironment www.crccare.com sites program through anationaldemonstration Fast-tracking sciencetothefield workshop program Extensive industrytrainingand contamination skilled atsolvingandpreventing Australian professionals highly Producing agenerationofyoung internationally and endusers,nationally industry participants,researchers Collaborations betweenmajor Cluster (ARIC) the AustralianRemediationIndustry technology andknowledgethrough Promoting industryaccesstonew
editor’s note Remediation Australasia is a quarterly industry magazine produced by When the seeds of CRC CARE were the Australian Reme- sown in 1999, the remediation diation Industry Cluster industry was worth $300 million per (ARIC) for the Australian year. Following the establishment remediation industry. of CRC CARE and ARIC, this figure has grown to more than $3 billion. International companies focusing on Circulation remediation have also increased in The publication is currently number, from a small handful to more distributed to more than 2,000 than 20. In this environment of rapid recipients throughout Australasia, growth, ARIC’s challenge – to drive free of charge. growth further and deliver even more value in the remediation industry – is Editorial and production Welcome, reader, to Issue 11 of significant indeed. Editor-in-chief Remediation Australasia. ARIC relies on researchers and Ravi Naidu I would like to extend a warm personnel involved with contaminated site assessment and remediation Editor welcome to those of you who have Adam Barclay recently joined ARIC. If you are a to contribute to workshops and newcomer, you may not be familiar conferences. These training Techical editor with our scope or purpose. ARIC was events are crucial in educating Prashant Srivastava launched in July 2007 to promote the policy makers and the community Australian remediation industry. Our about contaminants that harm the Editor, production goal was to make the industry more environment and human health, as Sharmin Patard editor’s note editor’s competitive by introducing advanced well as about potential liability issues. new site assessment and remediation Editorial enquiries The insights, case studies, reports, Adam Barclay, CRC CARE technologies, build capacity and explorations and innovations from our develop skills in these areas, and 08 8302 3925 magazine contributors and industry [email protected] share information about technology, members – along with our readers’ policy and market opportunities in support – are an integral to ARIC’s Front cover image: A Thiess Services Australia and beyond. ability to achieve its mission. In this remediation project in Western Australia How effective has ARIC been light, we are seeking to expand and saw the relocation of contaminated in fostering networking among disseminate our knowledge even further. landfill after the deployment of an industries, universities and policy innovative remediation technique. The current issue of Remediation Turn to page 20 to read the full story. makers, and, as a consequence, Australasia includes a particular expanding the remediation industry? focus on landfills. The large volume Articles which appear in Remediation Since its launch in 2007, ARIC of waste that we generate, much Australasia may be reproduced with has attracted around 2,500 of which finds its way into landfills, written permission from ARIC and members worldwide, and is now is an intergenerational issue – will CRC CARE. Acknowledgement of the technology diffusion arm of CRC we leave this for our children and the source of both the research and CARE. ARIC has actively: grandchildren to manage? To me, the story will be a requirement. This publication is provided for the purpose • built capacity in the remediation the concept of ‘zero waste’, although of disseminating information relating industry sector by hosting training admirable, is a pipe dream – we are to scientific and technical matters. workshops for new and imminent never likely to see a manufacturing Participating organisations of ARIC and graduates sector or individual households that CRC CARE do not accept liability for can exist without generating waste. any loss and/or damage, including • extended new technologies Tell us what you think – I welcome financial loss, resulting from the reliance by enhancing networking your thoughts on waste management, upon any information, advice or among companies, consultants, landfills old and new, and where you recommendations contained in this researchers and policy makers publication. The contents believe the remediation industry will of this publication should • collaborated with local Environment be 20 years from now. not necessarily be taken Protection Authorities to diffuse new As always, please contact us via to represent the views policy as well as the outcomes [email protected] if you have any of the participating of the National Environmental feedback or would like to contribute. organisations. Protection Measure, and We would love to hear from you. ISSN 2201-1714 • conducted workshops for industry Prof Ravi Naidu and government to identify knowledge gaps in environmental Managing Director, CRC CARE Printed on Certified Carbon Neutral, FSC Mix Certified, 55% recycled (30% pre consumer, 25% post-consumer) paper. and remediation industry policy. Editor, Remediation Australasia
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08 Landfilling the 20 An innovative energy gap approach to Taking a closer look at how landfills can relocating operate as biorefinery sites for biomass landfill production, and how to harness CH4 as a fuel source How do you relocate contaminated materials to a landfill cell, if the chemical classification isn’t right? A case 13 Mining landfills for study in using on-site chemical energy and more treatment of contaminated soils Using alternative waste treatment technologies to recover recyclable 24 Using materials and organic waste from mixed waste streams groundwater interception systems Heavy metal contamination 16 What to consider in water, and the power of when developing groundwater interception your sampling and systems – cleaning up the analysis plan legacy of zinc smelters The crucial first step in assessing the presence of contamination at a site where potentially contaminating
contents activities have occurred – developing a sampling and analysis plan (SAP)
4 Remediation Australasia Issue 11 2012 20 24
Photo competition Winner! 22
every issue
30 Australia’s 06 ReMEDIAtion landfill future Brief summaries of remediation Navigating policies, regulations and contamination in the media and legislative instruments on the complex and dynamic landscape of waste management in Australia 38 Research RoundUp An update on current research 34 Perception of focused on environmental brownfield contamination assessment and sites: Myth or remediation in Australia reality? Australia’s brownfield sites are 41 Training and often perceived by the public as events ‘risky’, despite potentially posing no risk. Learn more about public opinion and perceptions of 42 Publications brownfield sites, and the problems Update of remediating these sites
www.remediationaustralasia.com.au 5 Your guide to environmental ReMEDIAtion contamination and remediation Tas EPA approves first hazardous landfill Tasmania is set to get its first Category C landfill issues in the licenced to take hazardous waste, with the hope of getting rid of materials previously stockpiled or media sent interstate. Southern Waste Services – a conglomerate run by Kingborough, Sorell, Clarence City and Tasman councils – will build the proposed $10 million new landfill project. The group hope to build the facility at the Copping landfill site, which has Recycling trumps landfills been operating as a Class B landfill since 2002. The Copping landfill is located A new report confirms the Australian about 50km east of Hobart near Marion Bay. recycling sector is a bigger employer With a proposed void capacity of 300,000 cubic metres, the site recently and generates more revenue than the received approval from the Tasmanian EPA. The site would cover about 2.5ha landfill sector, but significant barriers on the 707ha site, which is currently a former quarry.Major hazardous wastes remain to its growth and development. waiting for a home in Tasmania include 200,000 tonnes of Jarosite from Nyrstar’s The report draws on recent figures zinc smelter in Hobart, but the site will also receive a range of hazardous wastes that 26 m t of material was recycled including acids, alkalis, inorganic and organic chemicals, paints, solvents, in Australia in 2008/09. The study pesticides, oil, clinical wastes and industrial sludges. See Using groundwater noted the value of recycling in interception systems on pages 24-28 for a case study on remediating Australia was around $6.145 billion. groundwater contaminated by heavy metals emanating from the smelter. Most of this revenue (50% or so) is More information: http://bit.ly/TASEPAhazwaste attributed to the sale of recovered materials, but the report cautions markets are highly variable. More than half ($3.8 billion) of the revenue ‘Plastic Oceans’ - a Catalyst report from recycling was generated in A plastic bag outlives its usefulness NSW and Victoria. after around 15 minutes. A plastic The contribution of the recycling sector bottle might last a little longer, party to Australian employment is estimated balloons a whole occasion. But at a little less than 1% - meaning the ocean likes to hang onto these approximately 22,000 people (full discarded treasures for decades, time equivalents) are employed in even centuries – giving many other recycling in Australia.This equates consumers a taste for plastic. Of to 9.2 full time employees for every concern is the prevalence of plastic 10,000 t of waste processed. being found in birds, in some cases INSET A plastic bag can spend centuries in the ocean. While recycling remains a relatively representing up to 8% (the equivalent small employer in Australia, the report of a person carrying 3 - 5 kg of plastic in their stomach). It’s estimated makes clear the environmental benefits neurological damage to infertility. of recycling are considerable. In total, that 3.5 m pieces of new plastic enter the world’s oceans daily. Carried It is estimated that fish in the North the report estimates recycling generate Pacific now consume up to 24,000 approximately 241,000,000 GJ- on global currents, they accumulate in huge circulating gyres causing t of plastic a year. As one predator equivalent of energy savings. This is eats another contaminates biomagnify. enough energy to power around 5 countless injuries to marine life along the way. This means the most vulnerable million homes. animal to the effects of toxic plastic A summary of the barriers impeding A nationwide study to tackle these contamination is the one at the very greater recycling put a lack of questions, and is the first time marine top of the food chain: us. With each investment in recycling and limited debris has been assessed on such a one of us contributing around 67 kg of infrastructure as the primary challenges huge scale. To fill in information gaps plastic waste a year, avoiding single facing the sector. A lack of business CSIRO is joining forces with Earth use plastics can make an enormous recycling uptake, the distance of Watch and training up volunteers. difference to the environment and materials to markets and consumer Mercury is just one of the many toxic ultimately are own wellbeing. behaviour are also key barriers. contaminants found in and on plastic More information: http://bit.ly/ More information: debris. Aside from death, mercury can CatalystPlastic http://bit.ly/RecycleReport cause a wide array of effects from
6 Remediation Australasia Issue 11 2012 Asbestos takes its toll Action needed to reduce hazards from chemicals Children who spent their childhoods ReMEDIAtion exposed to asbestos in the north- Coordinated action by governments and west of Western Australia are now industry is urgently needed to reduce the developing a range of cancers risks to human health and the environment or dying at a rate well above the posed by the unsustainable management of average population, according to a chemicals worldwide, according to a new new study by researchers from The report by the United Nations Environment University of Western Australia. Programme (UNEP). Mining of the potentially deadly blue These risks are compounded by the steady asbestos at Wittenoom, 1106km shift in the production, use and disposal of north of Perth, ceased in 1966 chemical products from developed countries and the town was later closed after to emerging and developing economies, airborne fibres in dust from mining where safeguards and regulations are often operations were found to cause weaker, says the report. malignant mesothelioma, lung UNEP’s recently released Global Chemicals cancer, asbestosis and other serious Outlook highlights the major economic diseases. A new asbestos study is looking burden caused by chemical hazards, at the long-term health of children While data collection has previously exposed to asbestos in WA. particularly in developing countries. Sound looked at asbestos-related diseases chemicals management can reduce these caused by occupational asbestos financial and health burdens, improve exposure among men (either working in asbestos mining towns or livelihoods, support ecosystems and reduce using asbestos products), this study is the first to look at the long- pollution. term health of children exposed to asbestos at Wittenoom. The release of the report - the first The study, published in the American Journal of Industrial comprehensive assessment of its kind - Medicine, shows that girls who lived in Wittenoom up to the age follows renewed commitments by countries of 15 have been more likely to develop mesothelioma, ovarian at the Rio+20 summit in June to prevent the and brain cancers and have had increased death rates. Boys illegal dumping of toxic wastes, develop who spent their childhood and early teenage years in Wittenoom safer alternatives to hazardous chemicals during the years that asbestos was mined (1943-1966) now in products, and increase the recycling of have elevated rates of mesothelioma, leukaemia, prostate, brain waste, among other measures. and colorectal cancer, diseases of the circulatory and nervous The Global Chemicals Outlook lays system, and excessive death rates. out other specific recommendations for These ‘Wittenoom kids’ are now reaching the age where chronic countries, corporations and civil society adult diseases are becoming more prevalent and many have to accelerate progress towards the 2020 died. goal, and ensure the sound management More information: http://bit. More information: http://bit.ly/Wittenoom of chemicals. ly/UNEPchemreport
US funds Agent Orange groundbreaking next week for the US to intensify its effort clean-up in Vietnam and ensure its commitment to reduce the public health impact in Vietnam. During the Vietnam War, what’s now known as Da Nang International Airport was a major storage depot for Agent Agent Orange was one of a class of herbicides that the US Orange. This was the name used for one of the powerful military used during the 1960s in Vietnam. It destroyed, it herbicides and defoliants used by the U.S. military in was a defoliant, it destroyed the vegetation over large areas, herbicidal warfare against opposing forces. Da Nang is just but along with it came this contaminant dioxin and this is the one of 28 former US Military bases that were contaminated source of today’s concern. Dioxin is highly poisonous. with toxic chemicals that continue to pose a health risk. America’s International Development agency,USAID, has Listen to this report at ABC Radio Australia: http://bit.ly/ committed more than $40 million to help clean up the ABCAgentOrange remains of Agent Orange at Da Nang Airport. Charles Bailey (director, Aspen Institute’s Agent Orange in Vietnam Program): It’s now 37 years after the end of the war, but the harmful affects of dioxin contamination left by the spraying of Agent Orange is still being felt by millions in Vietnam, including children. But recent progress has created a window of opportunity for the US symbolised by this
www.remediationaustralasia.com.au 7 LANDFILLS SPECIAL ISSUE Landfilling the energy gap
Nanthi Bolan, Balaji Seshadri and Ramya Thangarajan
While landfilling provides an economic means of waste disposal, if not managed properly, it can degrade the environment through the release of contaminants. The major environmental challenges associated with the sustainable management of landfills are surface water and groundwater contamination, and greenhouse gas (GHG) and odour emissions.
Landfills as a biorefinery for biorefineries – facilities that as adequate rooting substrate is Safe waste disposal is one of the process and convert biomass into maintained. products such as fuels, power, heat major environmental issues facing Increasingly, phytocaps are being and useful chemicals. This article society today, and landfills – sites considered for use at a range provides an overview on the role developed for the disposal of waste of waste-disposal sites in many of landfills as potential biorefinery material, which is usually buried countries, including Australia. This sites for biomass production and and covered with soil – provide the alternative technology enhances the harnessing CH as a fuel source. most economical and simple means 4 aesthetic qualities of landfills, many of disposing waste globally. For of which are adjacent to urban example, in Australia, the majority Revegetation technology to communities. It also introduces of municipalities have been manage landfill sites and to economic benefits such as biomass managing landfill sites for waste produce biomass generation for energy, timber and disposal, with more than 2,000 The primary objective of landfill fodder. Biomass feedstocks can be landfill sites estimated nationwide. design and management is to grouped into four general categories Despite a significant increase in the contain waste materials and limit (see far right). reduction, reuse and recycling of off-site transport of dust and The production of biofuel solid waste, disposal to landfill will leachate. Traditionally, landfill feedstock needs to address long- inevitably remain the most widely covers have been designed to term ecological sustainability, used waste-management method. minimise water entry through reduction in production costs, and In recent times many local the use of low permeability layers production on a large scale using governments have introduced (e.g. compacted clay caps and non-agricultural crops and sites engineered landfills with gas geosynthetic liners). However, that are not used for agricultural recovery systems, which aim to often this is not achieved because, production. However, some as landfills age, cracks form due capture methane (CH4) as a fuel agricultural crops can be grown source. Increasingly, revegetation to drying and wetting cycles. on landfill sites if they target (i.e. ‘phytocapping’) is practiced Therefore, constructed caps are bioenergy production and thereby in traditionally managed landfill vegetated to prevent exposure negate any threat to food security sites to mitigate the environmental and degradation of the clay or pressure on agricultural lands. impacts resulting from leachate barrier. Even though the primary The type of biomass required for generation and GHG emissions. management goal is to develop industrial energy production is Revegetation also provides a vegetation cover to increase principally determined by the major source of biomass for evapotranspiration and prevent energy conversion process and energy production, making such cap exposure, high-yielding plant the form in which the energy is landfill sites potential locations species may be established, as long
8 Remediation Australasia Issue 11 2012 THE FOUR BIOMASS FIGURE 1 Irvington Generating Station. Operated by Tucson Electric Power, the station produces electricity by fossil fuel combustion. The fuels used consist of coal, natural gas, FEEDSTOCKS liquid fuel and landfill gas. SOURCE Bill Morrow http://bit.ly/FlickrBillMorrow CATEGORIES
“Revegetation provides a major source ENERGY CROPS of biomass for energy production, herbaceous and woody crops, industrial crops, agricultural making landfill sites potential locations for crops and aquatic crops biorefineries – facilities that process and agricultural residues convert biomass into products such as fuels, and waste power, heat and useful chemicals.” crop waste and animal waste
required. Numerous plant species plants could also be used for biomass forestry waste have been tested for commercial production on closed landfill sites with and residues energy farming internationally. purpose-built phytocaps. An ideal mill wood waste, logging Perennial grasses/herbaceous plants in energy crop for a landfill site should residues, tree and shrub residues particular may be suitable for biomass have high yield and low nutrient
production on closed landfill. The4 C demand, and require low input for industrial and plants, such as Miscanthus, switchgrass maintenance and harvesting. municipal wastes and Napier grass have been proposed municipal solid waste, sewage as the main perennial grass species for Technologies for biomass sludge and industry waste energy production because of their conversion to energy high photosynthesis rates (plants Biomass can be converted into Some of these may be exhibit two main photosynthetic fuels and carbon-based products by produced on landfill sites and pathways, known as C and C , with 3 4 biochemical and thermochemical can be used in generation of the latter being more efficient and methods (see Figure 1). heat or electrical energy, or as characteristic of higher-biomass Thermochemical routes of biomass plants). In addition to grasses, woody transport fuels in the form of solid (e.g. wood), liquid (oil seeds) or gas. www.remediationaustralasia.com.au 9 FOUR BENEFITS OF LANDFILL GAS slow pyrolysis, heating of biomass oxygenated hydrocarbons and water takes place at slow heating rates from the original biomass. The major CAPTURE-AND- (5 - 80°C/min) and long residence constituent in TCL gaseous products
times (600-6000 s) and results in is CO2 (>70%) with traces of CO, COMBUSTION higher char yield compared with H , CH , C -C gases, NH and 2 4 2 4 3
high heating rate (1000°C/min) H2O. Char can be used as high-value PROJECTS with extremely short residence products such as soil conditioner. times (0.5-5 s) in fast pyrolysis. The Gasification is the conversion of Improved groundwater quality liquid yield in slow pyrolysis is low biomass into a combustible gaseous (30%) compared with fast pyrolysis resulting from effective leachate fuel by partial oxidation of biomass (75%). Hence, commercial collection and disposal at high temperature in the range of pyrolysis units adopt fast/flash 800-900oC. The process can take place pyrolysis to maximise bio-oil yield in air, oxygen or steam as the reaction Improvement of air quality through and produce biochar. Since biochar medium. The resulting gas, known as has an estimated longevity of 100 burning less coal for electricity producer gas (or syngas), is a mixture to 1000 years in soil, it can be generation and reduction of LFG of CO, CO , H , CH and N gases. considered as a significant means 2 2 4 2 released into the air The gas is more versatile than the for sequestration of CO from the 2 original solid biomass, and can be atmosphere to the soil. burnt to produce heat and steam, or Reduced risks of dangerous CH 4 Thermochemical liquefaction used in internal combustion engines gas concentrations (TCL) is the conversion of biomass or gas turbines to produce electricity. in sub/supercritical water reactions. Gas quality and composition can vary Reduced exposure of residential TCL resembles the pyrolysis depending on the gasifying agent, process in some ways, where the method of operation, operating areas to unattractive odours biomass is heated in an oxygen- conditions and biomass composition free atmosphere in the presence or and properties. absence of a catalyst that enhances conversion are more attractive and the hydrolysis, depolymerisation Methane capture as a fuel have certain advantages, including and condensation reactions to produce source higher productivity, complete bio-oil (also called bio-crude) as the Landfill gas (LFG) recovery, although utilisation of feedstocks leading major product along with gases, water an expensive technology, is being to multiple products, applicability solubles and char as co-products. implemented and adopted in many to a wide range of feedstocks, and However, unlike pyrolysis where the developed countries, including better control over the process biomass conversion takes place at Australia. Feasibility of LFG system relative to biochemical processes. near or slightly above atmospheric greatly depends on which gases, and Thermochemical conversion routes pressure, in TCL, biomass is converted how much CH , are emitted by the include pyrolysis, liquefaction and at significantly higher pressures (5 to 4 landfill. In recent years in Australia, gasification. 40 atm) and lower temperatures (280- LFG projects have increased in 370oC). A key difference is that TCL Pyrolysis is the thermal decomposition number and production, from only can process wet biomass without drying of biomass to liquid (bio-oil), solid 15 projects in 1998 to 42 in 2005, and is therefore energetically more (char) and gaseous products in the with a total electricity output of 103 efficient than pyrolysis. absence of oxygen at 350-700°C. MWh. Similarly, in the US, there Based on the operating temperature Bio-oil produced from TCL is usually has been a dramatic increase in the and residence time, the process is a dark brown, viscous liquid that has number of projects aiming to convert known as slow pyrolysis, intermediate a distinctive odour similar to pyrolysis LFG to energy. In 1999 there were pyrolysis, or fast/flash pyrolysis. In bio-oils and is a complex mixture of 300 operational facilities, which
FURTHER READING Bolan, NS, Thangarajan, R, Seshadri, B, Jena, U, Das, KC, residues obtained from different methods’, Applied Engineering Wang, H & Naidu, R 2012, ‘Landfills as a biorefinery to in Agriculture, vol. 27, pp. 107–113. produce biomass and capture biogas’, Bioresource Technology (accepted manuscript) doi: 10.1016/j.biortech.2012.08.135 Jena, U, Das, KC & Kastner, JR 2012, ‘Comparison of the effects of Na2CO3, Ca3(PO4)2, and NiO catalysts on the Bolan, NS, Park, JE, Robinson, B, Naidu, R & Huh, KY thermochemical liquefaction of microalga Spirulina platensis’, 2011, ‘Phytostabilization: A green approach to contaminant Applied Energy, vol. 98, pp. 368–375. containment’, Advances in Agronomy, vol. 112 , pp. 145–204. Jena, U & Das, KC 2011, ‘Comparative evaluation of Das, KC, Singh, K, Bibens, B, Hilten, R, Baker, SA, Greene, thermochemical liquefaction and pyrolysis for bio-oil production WD & Peterson, JD 2010, ‘Pyrolysis characteristics of forest from microalgae’, Energy Fuels, vol. 25, pp. 5472–5482.
10 Remediation Australasia Issue 11 2012 FIGURE 1 Conceptual biorefinery for production of fuels and value-added co-products from landfill waste via TCL, along with carbon sequestration. increased to 555 facilities in 2010 producing approximately 14 TWh electricity. Plant growth
Global CH4 emissions from landfill are estimated Plant residues/ to be in the range of 9-70 m t/yr. Introduction Municipal solid waste waste biomass of CH -capture cap designs, where LFG is 4 Landfill collected and combusted either as a source of electricity or disposal, is likely to reduce CH Processing 4 CH4 capture emissions by approximately 5 m t/yr. Capturing LFG helps to reduce odours and other hazards Biomass/organic wastes associated with LFG emissions, and reduces recycling the contribution of CH to global climate 2 Heat & electricity CO 4 recycling ACP change. Furthermore, combustion of LFG for Thermochemical the production of energy contributes to GHG liquefaction emission reduction in two ways. LFG capture
prevents the release of CH4 into the atmosphere
(as a GHG, CH4 is 25 times as powerful as CO2)
and the electricity subsequently produced by LFG Aqueous phase Gaseous products Bio-oil Solid residue/char co-product (ACP) combustion produces less CO2 than conventional Separation fossil fuel combustion. Upgrading C-sequestration Concentration LFG is often extracted from landfills using a
series of wells and a blower/vacuum system. This Fuel gas Liquid fuels Soil conditioner N, P, K system directs the collected gas to a central point Sale where it can be processed and treated according to its ultimate use. From this point, the gas can be flared, used to generate electricity, replace biomass production is relatively small compared with fossil fuels in industrial and manufacturing operations, other marginal and degraded lands such as mine sites, upgraded for direct use, landfill sites are readily accessible, thereby providing or processed into an alternative vehicle fuel. an attractive option for biomass production. Biomass Due to economic and infrastructure constraints, only a from landfill sites can be converted to energy through various processes including pyrolysis, gasification and small fraction of landfill CH4 is harvested and used for electricity production. Although LFG capture and use co-generation. has been widely practiced in developed countries, its Landfills with gas-recovery systems can be used to
application in developing countries could be limited by a capture CH4 as a fuel source. LFG capture is likely to number of factors, including lack of legislation enforcing contribute to a number of environmental and social LFG extraction with or without utilisation, unfavourable benefits including improved groundwater and air quality,
financial performance to attract investment funding, and reduced risks of CH4 gas emissions, reduced exposure lack of technology know-how and infrastructure. of residential areas to odour, and improved local employment opportunities and community programs. Filling the energy gap While the primary objective of phytocapping landfill This article is a condensed version of the resource paper: Bolan sites is to mitigate leachate generation, this technique et al. 2012, ‘Landfills as a biorefinery to produce biomass and can be used to revegetate the area with endemic plants capture biogas’, Bioresource Technology (doi: http://dx.doi. species for the creation of a natural ecosystem and to org/10.1016/ j.biortech.2012.08.135); further details can be produce biomass for energy production. found in the reference list at the bottom of the page. Although the potential landfill area available for
Jena, U, Das, KC & Kastner, JR 2011, ‘Effect of operating T 2011, ‘Biochar reduces the bioavailability and phytotoxicity of conditions of thermochemical liquefaction on biocrude production heavy metals’, Plant and Soil, vol. 348, pp. 439–451. from Spirulina platensis’, Bioresource Technology, vol. 102, pp. 6221–6229. Seshadri, B, Bolan, NS, Naidu, R & Brodie, K 2010, ‘The role of coal combustion products in managing the bioavailability of Lamb, D, Venkatraman, K, Bolan, N, Ashwath, N, Choppala, G nutrients and heavy metals in soils’, Journal of Soil Science and & Naidu, R, 2012 ‘Phytocapping: An alternative technology for Plant Nutrition, vol. 10, pp. 378–39. the sustainable management of landfill sites’,Critical Reviews in Environmental Science and Technology (in press). Venkatraman, K & Ashwath, N 2009, ‘Phytocapping: Importance of tree selection and soil thickness’, Water, Air, & Soil Pollution: Park, JE, Choppala, GK, Bolan, NS, Chung, JW & Chuasavathi, Focus, vol. 9, pp. 421–430.
www.remediationaustralasia.com.au 11
LANDFILLS SPECIAL ISSUE Trash and treasure: Mining landfills for energy and more
Paul Clapham, SKM Consulting
With its origin in the domestic midden, landfill Other forms of AWTs include the advanced thermal represents the oldest method of dealing with the waste technologies pyrolysis and gasification. The pyrolysis from human societies. However, landfill is increasingly process thermally degrades organic waste and plastics being seen as the least desirable option for managing our in the absence of air or oxygen to produce synthesis waste. The waste hierarchy (Figure 1) favours higher- gas (‘syngas’) which is rich in hydrogen and methane. order management options as such waste prevention, Gasification uses higher temperatures and sub- reuse of waste materials, recycling, and energy recovery stoichiometric quantities of air, oxygen or steam in preference to landfilling. In response to this, many to produce syngas from organic materials. Plasma nations have adopted (or are in the process of adopting) gasification is a technology that is starting to be used to legislation that requires the pre-treatment of waste recover energy from mixed waste streams through syngas before its disposal to landfill. For example, the European production, whilst facilitating the recovery of metals and Union’s Landfill Directive requires the pre-treatment of an inert slag from the inorganic fraction of the waste. waste sent to landfill within its member states (e.g. the The use of AWTs means that only residual materials are United Kingdom, the Republic of Ireland, Germany, sent to landfill, thereby helping to reduce society’s impact France, etc.). Some countries (e.g. Sweden), as well as upon the environment in terms of mineral extraction some municipalities in North America, have banned the whilst maximising the remaining void space in existing landfilling of organic waste and/or recyclable materials landfills. However, over a century of landfilling industrial such as metals, plastics, paper and glass. Nevertheless, and municipal waste has left us with a legacy of scattered it can be argued that there is a place for landfill as part sites, which in many cases represent environmental of an integrated waste management solution. In some hazards, but at the same time can be considered treasure circumstances, such as remote communities, landfill can troves of previously used resources. represent the best practicable environmental option for the management of waste. The rationale for this is that This article is the first of a series of three that considers the carbon impact of landfilling of recyclable materials landfill and landfill mining (i.e. the recovery of produced by remote communities is significantly energy and resources from landfills) in the context of less than that of transporting the materials to distant sustainable materials management. reprocessing plants. The Organisation for Economic Co-operation and A range of alternative waste treatment technologies Development (OECD) Working Group on Waste (AWTs) enable the recovery of recyclable materials and Prevention and Recycling has defined sustainable organic waste from mixed waste streams. For example, materials management (SMM) as an approach to mechanical biological treatment (MBT) is a generic promote sustainable materials use, integrating actions term for various combinations of sorting and separation targeted at reducing negative environmental impacts technologies that extract recyclable materials (including and preserving natural capital throughout the life cycle metals, cardboard, plastics, glass and other inert of materials, taking into account economic efficiency materials) from the organic fraction of municipal solid and social equity. The first policy principle of SMM is waste (MSW) and commercial and industrial (C&I) to preserve natural capital; the second is to design and waste streams. The separated organic fraction is either manage materials, products and processes for safety composted to produce a ‘compost like output’ (CLO), or and sustainability from a life-cycle perspective. At face alternatively it can be processed via anaerobic digestion value, SMM appears to have little in common with (AD) which produces biogas – a methane rich fuel that the landfilling of waste. However, if one considers can be burnt in an internal combustion engine or furnace landfills as potential repositories of resources, then to produce electricity. The CLO and digestate (the semi- their exploitation through landfill mining can help solid material left over in the AD reactor once the process satisfy the first policy principle of SMM; the better has completed) can be used to restore brownfield sites. management of recovered resources through the
www.remediationaustralasia.com.au 13 FIGURE 1 The waste hierarchy or a geosynthetic different categories of landfill, or Most preferred option membrane to prevent are deposited into separate cells the contamination within the same landfill. Thus, of groundwater; and older landfills typically contain is equipped with a wide variety of waste materials Reduce extensive collection that have been deposited in an and treatment unstructured way; whereas more systems for leachate modern landfills generally contain Reuse and landfill gas. wastes that are more consistent Many large landfills in character – though the Recycle in Europe and North composition of different municipal America are now waste streams can vary considerably substantial generators between different councils within Energy recovery of renewable energy the same country. from the combustion In its simplest form, landfill of landfill gas (which Landfill mining can take the form of is rich in methane), scavenging – a practice that is produced by the all too common in developing Least preferred option decomposition of countries. Health and safety the organic matter risks alone make the scavenging in the waste (also of landfills an unacceptable see ‘Landfilling the practice, but it can be difficult to production and consumption life- energy gap’ on p. 8). The collected outlaw such activities where local cycle (Figure 2) can help satisfy landfill gas is burnt in dedicated employment opportunities are policy principle 2. gas engines on site to produce limited, and there is insufficient electricity which is exported to the Before considering landfill resource available to enforce local grid. mining in detail, it is important laws and regulations forbidding to understand the history of Over time, the range of wastes that such activities. landfilling, and how the age have been landfilled has varied, and composition of a landfill reflecting our changing culture. “In its simplest form, influence its value in terms of the The industrialisation of society has resources that it may contain. led to the production and disposal landfill mining can Up until the mid-1970s, landfills of industrial wastes (many of which (even within developed nations are toxic), as well as changes in take the form of in Europe and North America) the composition of the municipal scavenging – a were unsophisticated affairs waste stream (i.e. waste that is that bore closer resemblance collected from households and practice that is to dumpsites than designated similar properties by councils). In waste management facilities. In the past it was common practice to all too common traditional societies, the contents dispose of both municipal wastes in developing of dumpsites were largely of and industrial wastes (including organic origin and the material liquid wastes) in the same landfill countries. …At the decayed over time releasing the – a process known as co-disposal. greenhouse gases carbon dioxide Much of this disposal of waste was other end of the (during the aerobic phase) and unregulated and led to significant spectrum, industrial methane (during the anaerobic local environmental and health phase). Other environmental impacts. technologies can issues included odour problems from the decaying matter, and the Reforms in landfill practices have be applied to the production of a liquid leachate been gradually introduced in with a high biochemical oxygen North America, Europe, and other mining of landfills.” demand (BOD) that was capable of parts of the world over the course adversely affecting water quality in of the last 30 years, which has At the other end of the spectrum, the local area. meant that liquid wastes are now industrial technologies can be either treated or solidified before applied to the mining of landfills. By contrast, a modern sanitary being sent to landfill and MSW In its most developed form, landfill is typically a well-engineered and C&I waste are either sent to landfill mining recovers more facility that is lined either with clay
14 Remediation Australasia Issue 11 2012 than just energy from the decaying landfill is usually poor, making • fly ash (the fine-grained waste. The true purpose of landfill them unsuitable for recycling. This material that is carried through mining is to maximise resource material is usually added to the by the combustion gases), and recovery from both closed and recovered organic fraction (which • air pollution control residues, operational landfills. The re- may include partially decomposed that are usually highly caustic opening of a closed landfill can paper, cardboard, wood and woody due to the use of an excess be problematic. In older landfills, vegetation) to produce a waste- of lime to neutralise the acid the distribution of different waste derived fuel that is fed into an gases. types within the landfill mass can energy recovery plant. hamper the efficient recovery of More recently, plasma technology There is a variety of energy from valuable materials from the waste has been applied to landfill mining. waste processes that can be used mass; the disturbance of the waste This process treats the recovered to process material recovered from material can cause health, safety, waste at temperatures in excess a landfill. Combustion plants o and environmental issues. Where of 2,000 C which vaporises the using reciprocating grates are the there is no documentary evidence organic material in the waste (both mainstay of the energy from waste about the waste that was deposited the plastics and the vegetable industry. Modern energy-from- in a landfill, it is good practice to matter) to produce a hydrogen- waste plants are complex facilities investigate the waste mass using rich syngas which is combusted that control the combustion of the bore holes or sample pits, to build to produce electricity. The metals waste to minimise the production up a picture of the waste present present in the waste melt to form of furan and dioxins. while acid in the landfill before mining a pool of molten metal that can gases and heavy metals are removed commences. be tapped off. The various metals from the flue gases using a variety can then be separated out using The extraction of the waste material of clean-up equipment including metallurgical processes. Any from the landfill can be achieved lime injection, bag filters and inorganic matter present in the through the use of mechanical electrostatic precipitators. The waste fed to the plasma gasifier diggers which feed a combination residues from the combustion becomes a vitrified slag that has a of sorting and separation process are low leaching potential and can be equipment to recover metals, and • incinerator bottom ash (the used as a construction material, separate out the dense inorganic burnt material that is left on engineering fill or road base. material such as builder’s rubble, the grate after it has passed The increasing scarcity of certain stones and glass. The quality of the through the combustion resources (such as semi-precious plastics that are recovered from chamber) metals that are used in computer circuit boards and other electronic equipment) as well as rising energy costs will help to stimulate further interest in landfill mining. In addition, landfill mining has the Manufacture of goods potential to help restore degraded land for productive use, as well Use of goods Mineral extraction as cleaning up environmental & harvesting of biological resources problems due to poor waste management practices in the past. The next article in this three-part series will take a more detailed look
Recycling at the technologies that are used to mine landfills, whilst the final Landfill of treated residual material article will consider the concept of enhanced waste management – an approach that considers the use of landfills as temporary stores of Recovery materials until economic conditions or technological advances make their recovery viable.
FIGURE 2 The production and consumption life cycle
www.remediationaustralasia.com.au 15 ARTICLE 3 OF 3: CONTAMINATED SITES SERIES
Using your conceptual site model: What to consider when developing your sampling and analysis plan
Ruth Keogh and James Corbett, Parsons Brinckerhoff
The development of a sampling and analysis plan To develop an appropriate SAP, it is important to (SAP) is the first step in the implementation of an consider the following issues on a site-specific basis. intrusive investigation program to assess whether It is also prudent to allow some flexibility once field contamination is present at a site on which potentially personnel are deployed, field conditions are better contaminating activities have occurred. Every SAP understood and professional experience and judgement must include clear objectives and should detail can be brought into play. information such as sampling patterns, locations and depths, appropriate field methodologies, laboratory What are your objectives? analytical programs and procedures, and quality Establishing clear objectives is a fundamental first assurance/quality control (QA/QC) requirements. step and should take account of factors such as To ensure that a SAP provides the best possible chance client requirements, current and future land uses of encountering any contamination present at the site, and the phase of work underway. For example, the it is essential to base this plan on the foundation of requirements of an initial site investigation program knowledge obtained during the site characterisation may vary substantially to those of a validation program and historical investigation program1, and refined undertaken subsequent to remediation whereas in the via the development of the preliminary conceptual latter stages of site investigation (when remediation site model (CSM).2 A CSM is a written or a pictorial is likely to be required) it is also important to collect representation of an environmental system and the additional site data (e.g. geophysical properties) biological, physical and chemical processes that relevant to remediation design. determine the transport of contaminants from sources To this end, the data quality objective (DQO) process through environmental media to environmental (as defined by US EPA (2000)4 and discussed in 3 receptors in the system (ASTM International E1689- Standards Australia (2005)4) can provide valuable 95 (2008) Standard Guide for Developing Conceptual assistance in structuring an investigation program Site Models for Contaminated Sites). such that relevant questions are posed at the start, As with the development of a CSM, intrusive site an appropriate SAP is developed and optimal data investigation may prove to be an iterative process if are obtained. A DQO also helps organise a complex contamination is present, and a SAP should therefore problem into a series of more manageable problems. be developed for each stage of work, taking account of the results obtained during any preceding stages.
FURTHER READING 1 Keogh, R & Corbett, J 2012, ‘Developing a comprehensive 4 US EPA 2000, Guidance for the Data Quality Objectives conceptual site model: What should you be looking for and Process QA/G-4, EPA/600/R-96/055, Office of Environmental where?’, Remediation Australasia, Issue 8 Information, Washington DC. 2 Keogh, R & Corbett, J 2012, ‘Developing a comprehensive 5 Standards Australia 2005, Guide to the Sampling and conceptual site model: Using your site history information Investigation of Potentially Contaminated Soil Part 1: Non-Volatile effectively?’, Remediation Australasia, Issue 10 and Semi-Volatile Compounds, Australian Standard AS4482.1- 3 ASTM International 2008, Standard Guide for Developing 2005, Sydney, New South Wales. Conceptual Site Models for Contaminated Sites, E1689-95..
16 Remediation Australasia Issue 11 2012 Which samples should you submit for laboratory analysis, and what should you analyse for?
The nomination of samples for laboratory analysis, and the choice of appropriate analytes, can be based initially on the results of the site history investigations and preliminary CSM, with consideration given to the following: • likely sources of impact (surface vs. subsurface chemical application/release) • possible preferential migration pathways (media and depth(s) most likely affected) • likely contaminants of potential concern/behaviour (e.g. persistence, mobility) and possible breakdown products of individual chemicals, and/or • data requirements for remediation design (including geophysical requirements). Field conditions will also play a pivotal role in refining the analytical program. Factors such as the presence of imported fill material(s), inclusions of foreign bodies capable of causing contamination (e.g. asbestos or ash/ cinders/slag), abnormal field parameter (e.g. photoionisation detector or water quality) results, and visual or olfactory evidence of contamination (e.g. odour, staining) should prompt sample selection for relevant analyses and may result in the modification of the original SAP.
What should you look for characterisation and historical Consideration should also be given and where should you look? investigations, as well as the to obtaining background data in There are a number of strategies preliminary CSM, taking into order that regional conditions can that have been developed to account the following: be defined and naturally occurring substances identified. maximise the efficiency and • site area robustness of sampling programs, • confirmed and/or likely For subsequent site assessment including accelerated site contaminant source locations, programs, the project objectives characterisation techniques which as identified from: (e.g. delineation of previously advocate the collection of large identified contamination, - locations and types of current volumes of low-resolution data validation of excavated areas and/or and former site infrastructure to provide good spatial coverage collection of data for remediation and other relevant features of a site, rather than just high- design) as well as available field and resolution data at limited sampling - current and former site laboratory data will play a strong points. Whichever sampling activities role in determining the scope of strategy is employed will be highly • likely soil profile, depth to the sampling program. dependent on site characteristics groundwater and the nature of and project objectives. Factors the aquifer(s) underlying the such as relevant media, appropriate site sampling patterns (e.g. random, • possible preferential targeted/judgemental, stratified contaminant migration and/or systematic), locations and pathways, and depths should be identified based • potential receptors, exposure on the results of the previous site pathways and routes.
www.remediationaustralasia.com.au 17 How should you ensure techniques will be largely dictated • selection of analytical that appropriate field by a combination of the project laboratories that are accredited methodologies and QA/QC objectives, field conditions, by the National Association procedures are adopted? nature of contaminants, likely of Testing Authorities for the extent of impacts, required data selected analytes, and Guidance on relevant field and professional judgement. QA • stipulation of required analytical methodologies and QA/QC procedures should include the parameters, including laboratory procedures is available in a following (as a minimum): detection limits (i.e. taking number of publications relevant to • employment of trained and account of relevant screening Australian conditions, including experienced personnel in the criteria and/or remediation (but not necessarily limited to): field goals) and analytical procedures. • Australian/New Zealand • recording of detailed field Standard (1998) Water Quality In addition to the above, notes, including soil logs, well Sampling, Part 1: Guidance on consideration should also be given construction information and the Design of Sampling Programs, to obtaining any necessary permits water purging/sampling records Sampling Techniques and the or clearances, as well as developing Preservation and Handling of • use of dedicated sampling an appropriate health, environment Samples. AS/NZS 5667.1:1998 equipment or decontamination and safety plan prior to attending of sampling equipment prior to, the site. • Department of Environment and between, the collection of (1998) Draft Guidelines for The Standards Australia document individual samples the Assessment & Management for Australian Standard AS4482.1- of Contaminated Land in • calibration of field instruments 20054 states that ‘no sampling Queensland and recording of calibration plan, however exhaustive, data • Department of Environmental can completely eliminate the Protection (2001) Development • correct location of proposed possibility that contaminants are of Sampling and Analysis sampling points, in accordance present on a site – a satisfactory Programs. Contaminated Sites with SAP plans, adjusted as sampling plan is one which has an Management Series required on the basis of field acceptable probability of detecting conditions and observations the presence of contaminants’. • EPA Victoria (2000) However, basing your SAP on a Groundwater Sampling • recording of individual firm foundation of knowledge Guidelines sampling locations (e.g. GPS co-ordinates, surveying) regarding the site (as defined in • National Environment the CSM), rigorous planning, and • unique identification of Protection Measure (1999) adapting your approach in response individual sampling locations National Environment to field conditions will provide the and samples Protection (Assessment of Site best chance of encountering any Contamination) Measure: • use of laboratory-supplied site contamination present. Schedule B(2) Guideline on Data sample containers with Collection, Sample Design and appropriate preservatives (where Reporting required) • South Australian Environment • collection of QC samples Protection Authority (2007) in accordance with rates Regulatory Monitoring and stipulated in relevant standards Testing Groundwater Sampling or guidelines, including blind • Standards Australia (2005) coded field duplicate and Guide to the Sampling and triplicate (spilt) samples and Investigation of Potentially blanks (equipment rinsate, trip, Contaminated Soil Part 1: field and container) Non-Volatile and Semi-Volatile • appropriate sample preservation Compounds. AS4482.1-2005 following collection and during transport The choice of appropriate field techniques should be primarily • transportation to analytical aimed at collecting representative laboratories within specified and reproducible data. To this analyte holding times and using end, the selection of field sampling chain-of-custody documentation
18 Remediation Australasia Issue 11 2012 JOINT AUSTRALIAN AND NEW ZEALAND SOIL SCIENCE CONFERENCE Soil solutions for diverse landscapes
WREST POINT HOTEL AND CONVENTION CENTRE, HOBART, TASMANIA 2 – 7 DECEMBER 2012
The Tasmanian Branch of Soil Science Australia invite you to the Island State to experience our rugged landscapes, beautiful forests, diverse soils and sample our cool climate food and wine. Come to Hobart from 2 – 7 December 2012 and “Discover Tasmania”. Photographic Acknowledgment: Tourism Tasmania.© George Apostolidis Tasmania.© Tourism Photographic Acknowledgment:
Visit the conference website for more information www.soilscience2012.com
www.remediationaustralasia.com.au 19
9619_Soil_Science_A4_Ad.indd 1 31/08/12 2:31 PM LANDFILLS SPECIAL ISSUE
Reducing contamination levels: An innovative approach to relocating landfill
Michelle Cousins and Ian Brookman, Thiess Services
A remediation project in Western Australia has used a new method to chemically treat contaminated soils on- site, thereby reducing the chemical classification to a lower class. This process enabled the reclassified material to be relocated to a landfill cell. These works were the first of their kind in the Pilbara region; only a handful of similar projects have been undertaken in Perth.
A joint remediation venture between Thiess’ construction • the excavation of 180,000 m3 of contaminated waste and services arms, and Hicks Civil & Mining, has and 70,000 m3 of non-contaminated material successfully completed a $30 million contract at the Rio • sorting and classifying of existing landfill cell contents Tinto Cape Lambert Port Facility. Named ‘Garlanja’, • bulk earthworks the venture is unique in its approach to fostering the employment and training of an Aboriginal workforce in • road and drainage works, and Western Australia, and also in its approach to remediation. • works to construct a new best-practice landfill cell. Cape Lambert is one of the sea ports used to export iron The landfill contained significant amounts of asbestos, ore from Rio Tinto’s mining operations in the Pilbara. hydrocarbon and heavy metal-contaminated soils, Rio Tinto is developing the port to more than double its batteries, oil drums, conveyor belt, concrete, general annual capacity, and so Garlanja was contracted to move waste and scrap steel. the existing 40-year-old Cape Lambert landfill to enable Once the waste was sorted, tested and classified, road construction of the port facility’s stockyards. trains hauled it to the new landfill site. The newly The landfill, constructed in the 1970s as part of the classified Class 1 landfill was constructed using a series original Cape Lambert Port, needed to be relocated of bunds and included a high-density polyethylene about 5 km from its current location. This relocation (HDPE)-lined Class II cell. When finished, the landfill took the Garlanja team nearly 11 months to complete, was closed with more than 48,000 m3 of clean material during which a total of 250,000 m3 of waste were including a 1 m-thick cap. The works also included recovered from the old landfill. The remediation and security fencing, access road construction and future cell relocation works included preparation.
20 Remediation Australasia Issue 11 2012 “This (project) avoided the transport of more than 20,000 tonnes of contaminated waste over 1,600 km to Perth for disposal at specified landfills. The technology... has set the precedent for contaminated waste management methods in the Pilbara in years to come.”
During works, high-efficiency particulate air filters blend of cementitious material and activated carbon were fitted to all machines to filter potentially asbestos- to the contaminated soil to immobilise and stabilise contaminated soil. Work practices were reviewed and the hydrocarbons and heavy metals. This avoided the modified where required to provide a safe workplace. transport of more than 20,000 t of contaminated To ensure any contaminated materials were handled waste over 1,600 km to Perth for disposal at specified without risk, ongoing monitoring and sampling landfills. The technology, along with significant savings of groundwater, dust, fibrous building materials, to the client and the environment, has set the precedent hydrocarbons, gases and heavy metal particulates was for contaminated waste management methods in the undertaken throughout the excavation process. Pilbara for years to come. The project was successful on a number of fronts, A treatment first including no lost time injuries on site over 67,000 Garlanja, in consultation with the client, project work hours, and a 25% cost reduction through the managers Sinclair Knight Merz, and the Western use of the treatment process. Rio Tinto’s head office in Australia Department of Environment and London commissioned an audit of the Cape Lambert Conservation, proposed a method to chemically treat Project which included all aspects of health, safety and the class IV contaminated soils on-site. This reduced environment. A special commendation was given by the the classification of the contaminated soil containing auditors for the immobilisation works at the landfill. hydrocarbons and heavy metals to a lower class and The works were recognised as being innovative and enabled the reclassified material to be relocated to the exceeding the scope, rather than just being compliant new cell. The method involved adding a proprietary with the works specified.
www.remediationaustralasia.com.au 21 Announcing the WINNERS of the Remediation Australasia photo competition!
Back in July, we asked you for your photos of all things environmental. The photos we received from across Australia showed us how many different industries our readers come from! The winning entry was from Mark Hunter (right), with his image of a dust monitoring consultant.
As it was such a difficult competition to judge, with a spectacular array of images from stunning locations, gorgeous environmental scenes, curious images of laboratory work and a unique insight into on-site investigations, we’ve also included two notable entries that caught also our eye. Visit www. facebook.com/CRCCARE to browse even more entries. Taken a photo lately that you’d like to share with us for publication? Flick it to [email protected] and we can come up with a story to match for future issues. Submitted by Prue Pettett, CDM Smith. Underground mining practices will help ensure the habitat of Limnodynastes ornatus (ornate burrowing frog) will remain intact – Submitted by Ben McCarthy, LandCorp. An impact compactor traverses a site in the Australian taken during field assessments in the Emerald region for Marine Complex (Henderson, WA) following geotechnical improvement works. Instead of removing a proposed underground mining project, which is set acid sulfate soil, high-impact energy dynamic compaction methods minimised waste, environmental demonstrate how farming and mining can work together. management requirements and cost. The site is now home to significant marine, oil and gas-based companies, and is critical to servicing the oil and gas fields off Australia’s north-western shelf.
22 Remediation Australasia Issue 11 2012 Announcing the WINNERS of the Remediation Australasia photo competition!
Submitted by Mark Hunter, JBS Environmental. This photo, taken through some piling ducts, depicts a colleague dust tracking on a job in Sydney’s west.
Submitted by Prue Pettett, CDM Smith. Underground mining practices will help ensure the habitat of Limnodynastes ornatus (ornate burrowing frog) will remain intact – taken during field assessments in the Emerald region for a proposed underground mining project, which is set demonstrate how farming and mining can work together.
www.remediationaustralasia.com.au 23 GROUNDWATER REMEDIATION
Nyrstar’s Hobart zinc smelter: Using groundwater interception systems
Barry Mann, GHD Pty Ltd FIGURE 1 Final design layout of Nyrstar’s groundwater interception system (GIS) The Derwent estuary is a place of extraordinary natural beauty and great biodiversity. Situated at the heart of the Hobart metropolitan area, it is the largest estuary in south- eastern Tasmania, covering almost 200 km2.
Despite the estuary’s iconic status, Nyrstar recognised that groundwater 2005-06 Nyrstar retained GHD to sediments in the lower Derwent show contamination remained a major conduct a review of existing pilot extremely high levels of heavy metal pollution and compliance issue. groundwater remediation schemes, contamination, in part as a result of followed by detailed hydrogeological Between 1996 and 2002, the majority the activity of the nearby zinc smelter, investigations in 2006-07. The of heavy metals entering the Derwent formerly operated by Pasminco and latter included additional nested from the smelter were considered now owned by mining and metals monitoring bores, pumping test and to be associated with diffuse, rather company Nyrstar. analysis, and hydrochemical analysis, than point sources, and groundwater to provide a better understanding The state government-funded Derwent appeared to contribute the largest of site groundwater conditions Estuary Program (DEP) has found proportion of heavy metals. Existing relevant to remediation design. that levels of mercury, lead, zinc and pilot systems intercepted some of the Using the results, GHD produced cadmium in sediments and aquatic heavy-metal loading in groundwater preliminary designs for a full-scale (benthic) organisms exceed national discharged to the Derwent River, but groundwater remediation system, guidelines, to the point that it Nyrstar’s groundwater interception with key objectives of maximising cautioned against consuming fish from system (GIS; Figure 1) aims to provide metals recovery underneath the the Derwent in general, and advised significant further reductions. main source (the electrolysis plant) against consuming shellfish altogether. Responding to the need to remediate while minimising operation and While this situation has improved, the existing contamination, in maintenance requirements.
24 Remediation Australasia Issue #7 Spring 2011
The 2013 ICOBTE Conference Organizing Committee Hydrogeology cordially invites you to The site is located on a rocky headland, participate in the and the steep hydraulic gradient present between the electrolysis plant and the Derwent River (in the order of 0.1 to 0.2 m per metre) reflects the steep 12th International topographic gradient (Figure 3). The estimated range of groundwater Conference flow velocities at the site is between 70 on the and 150 m/year. These are relatively fast groundwater flow rates, with important implications for a groundwater Biogeochemistry of remediation system, which would need to cope with transient, high-rate, low- Trace Elements volume groundwater conditions. The site geology (Figure 2) is characterised by two main bedrock June 16 - 20, 2013 types: Jurassic-aged dolerite (brown Athens, Georgia, USA coloured zone) and sandstone (green coloured zone). The two bedrock types are separated by a large fault The biennial ICOBTE Conference brings together zone which runs directly beneath scientists, professionals and policy makers. the electrolysis plant. Detailed It provides a multi-disciplinary arena for hydrogeological investigations discussing the latest scientific developments. identified horizontal layering in the Areas of interest include the biogeochemistry dolerite. Two saturated zones were of trace elements and metalloids, analytical identified generally between 5-15 methods for trace element detection, m, and 20-25 m depth respectively, speciation and bioavailability, recent advances in which are separated by a massive, remediation technologies and regulatory measures unsaturated layer ranging from 5 to for trace element contaminated sites. 15 m thick. Pumping test analysis indicated shallow aquifer permeability in the order of 0.3 to 0.5 m/day. Deep aquifer permeability was approximately one third of the shallow aquifer. Importantly, testing did not indicate IMPORTANT that the faulted zone was acting as a preferential pathway for groundwater DATES FOR 2012 contamination. November 01 Deadline for online abstract The dissolved zinc plume is situated submission directly down hydraulic gradient
of the electrolysis plant (Figure 4), November 30 Early online registration and extends to the Derwent River approximately 400 m away. The high levels of zinc – and to a lesser extent, cadmium and copper, which remain dissolved due to the low pH (2 to VENUE 3) groundwater – were attributed to University of Georgia historic and current releases from zinc sulfate as well as acid feedstock Conference Center & Hotel storages and pipes in the vicinity of www.georgiacenter.uga.edu/uga-hotel the electrolysis plant. Dissolved zinc concentrations range from 82 to 13,700 mg/L, averaging around 7000 mg/L downgradient of the plant. for further information visit the conference website:
www.icobte2013.org/www.remediationaustralasia.com.au 25
FIGURE 2 Geology of Nyrstar’s zinc smelter site
Dissolved zinc flux to river Based on the advective flow rates and mapped zinc concentrations, the estimated flux of dissolved zinc to the Derwent River ranged up to 130 tonnes per year. The current groundwater recovery schemes remove an approximate total range of between 40 and 70 t/yr.
Conceptual site model - conceptual system design The conceptual system design was based on a The conceptual system design was based on a series of horizontal bores, spudded in at a location FIGURE 3 Groundwater elevation contours across the site. topographically lower than the electrolysis plant and terminated at a specified depth below the plant. The bores would then free-drain any groundwater intercepted beneath the plant and the bore entry point. While the concept of free-draining horizontal bores (commonly used to dewater mine pits) is not new, the key unknown construction variables which significantly influence costs are: • how many bores are required • how long the bores need to be, and • how deep the bores need to be to provide effective capture of contaminated groundwater between the plant and the river.
System design modelling To answer the above questions, a three-layer numerical groundwater model (Visual MODFLOW) combined with a particle tracking model (MODPATH) was built to assess the degree of capture provided by different bore layout designs. The bore numbers, lengths, angles and termination depths were all subject to design FIGURE 4 The extent of zinc groundwater contamination around the electrolysis plant in March 2007 modelling. A total of 14 different designs, both free- draining and pumping, were evaluated. Flow data from the existing horizontal pilot bore (referred to as EB02) were used to assist in calibration (Figure 5). The green line in the top left corner, and near and parallel to the river, is EB02. Note that the model predicts particles to bypass EB02 and discharge to the river (purple cells). The Nyrstar GIS design was based on a series of 13 free-draining, 150 mm diameter horizontal bores ranging in length from 160 to 220 m each, with a total length of just under 2,000 m. The horizontal bores are arranged in a fan-like pattern, grade upwards at 1:125, and terminate at between 20 to 22 m below the electrolysis plant. The green lines represent the horizontal bores, while the blue lines indicate the path of a particle in groundwater. This design provided the greatest degree of capture (approximately 90%) in the area of highest zinc concentrations, located between the electrolysis plant and the process control building, and was free-draining. The latter was an important objective for Nyrstar, who wanted to keep operation and maintenance requirements to a minimum.
26 Remediation Australasia Issue 11 2012 The model design was used as a basis for technical specifications for drilling contractor tenders. The successful tenderer was selected primarily on their ability to track the borehole position and grade with high accuracy. This was an important consideration, given that the number, angle, termination depth and grade of the boreholes were critical to capture efficiency and, just as importantly, the boreholes were to be drilled underneath critical plant infrastructure. The bores were manifolded together and flow is directed to a wastewater storage pond. The system was commissioned in August 2008 and first operated in September 2009. The horizontal bores were spudded into a large retaining wall, taking advantage of a cleared area due to recent decommissioning of an old plant area (Figure 6).
FIGURE 5 The calibrated flow Performance monitoring results and particle tracking model. The system performance was measured by four key indicators: station. Inflows ranged between 13 to 34 3m /day, • predicted vs. measured drain inflows averaging around 16 m3/day (i.e. approximately half of • drawdown of the shallow aquifer water table in the the predicted inflow). vicinity of the borefield This is probably due to the highly variable rainfall • the concentrations of heavy metals in intercepted conditions during the monitoring period, to which groundwater, and the borefield is very responsive. The ability to respond • the mass recovery rate of heavy metals in to increased rainfall, groundwater recharge and intercepted groundwater. generation of contaminant plumes was a key objective of the free-draining system. Drain inflows Predictions of the inflows to the drainage borefield Watertable depression between electrolysis indicated a steady state inflow to the borefield of plant and river approximately 30 m3/day. Inflows for the period Drawdowns measured in monitoring bores located were measured (including an assumed average inflow downgradient of the electrolysis plant screened in of 15.5 m3/day for March–September 2010, when the shallow aquifer were plotted, indicating a drop in measurements were not taken), taking account of daily water level, varying from a 3-4m decrease in MB77 rainfall and 30-day moving average rainfall at Lutana and MB79 (shallow aquifer), to an approximately 0.8 m drop in MB84 (deep aquifer). The smaller degree FIGURE 6 The finished bore manifold at the base of the retaining wall. of decrease in MB84 is attributable to the deeper water level in this bore (around 12 m) and therefore the smaller head over the drainage bores, relative to the other bores (between 1 and 4 m). In general, the data showed that the water table underneath and downgradient of the electrolysis plant is being depressed, indicating successful capture of contaminated groundwater in the key source area. The recovery of water table levels after December 2009 was due to shutting in of the system.
www.remediationaustralasia.com.au 27 Metals concentrations in bores are installed into dolerite terms of volume and mass, 1 m3 intercepted groundwater rock, whereas downriver bores are (1,000 L) of groundwater contains installed in sandstone. Heavy metal on average 7 kg of zinc. Figure 7 is a combined plan concentrations were recovered by and plot which shows the zinc the GIS for the period September concentrations in intercepted Mass recovery rates 2009 to March 2010, showing groundwater. Figure 8 shows the total mass an average zinc concentration of of heavy metals and inorganics around 7,000 mg/L, with other Zinc concentrations were captured by the GIS for the period metals at concentrations an order measured in individual bores, as September 2009 to August 2012. of magnitude lower. It is unclear of December 2008, approximately The mass recoveries have been whether the different hydrogeology 2 months after commissioning. estimated based on average daily is responsible for the variation in The highest zinc concentrations recovery rates. The figure does zinc concentrations, or whether occurred in the upriver bores, not include the estimated 3,500 this is due to differences in plant located under the western end m3 of groundwater generated operation and spill locations. In of the electrolysis plant. These during system commissioning, when all bores were full of backed- up groundwater. At an average concentration of 7,000 mg/L zinc, the commissioning water is estimated to have contained approximately 25 tof zinc. The mass recovery rates represent the removal of environmentally significant amounts of heavy metals from the Derwent River ecosystem. The Nyrstar GIS will provide an ongoing, low-maintenance means by which to significantly reduce heavy-metal loading to the Derwent River, and represents a marked improvement to the sustainable management of this critical ecosystem.
FIGURE 8 Mass recovery rates of heavy metals and sulfate FIGURE 7 Zinc Concentrations in Nyrstar GIS as of December 2008
28 Remediation Australasia Issue 11 2012 MAJOR CleanUp 2013 incorporates Australia’s Conference premier contaminated site and themes remediation industry forum: • Site the 5th International Contaminated characterisation Site Remediation Conference • Risk assessment and characterisation • Human health: Hold The Date effects of 15–18 September 2013, exposure to contaminants Crown Conference Centre, Melbourne • Soil and sediment assessment and remediation • Groundwater assessment and remediation • Soil and waste treatment facilities • Landfills • Environmental drilling • Sustainability • Regulatory and legal • Communication and social www.cleanupconference.com www.remediationaustralasia.com.au 29 LANDFILLS SPECIAL ISSUE
Living with waste: Australia’s landfill future
Jade Herriman, Dustin Moore, Anna Gero, Damien Giurco, Stuart White, Leah Mason and Dana Cordell, UTS Institute for Sustainable Futures
Waste management in Australia is a complex and dynamic landscape, featuring a large and varied group of stakeholders including operators, regulators, entrepreneurs and community members, with varying levels of interest and awareness of waste issues. These groups are required to navigate a range of policies, regulations and legislative instruments from the national to the local level.
Currently, landfills play a significant role in the There is an extensive body of literature on the direct (or management of waste within Australia, where historically ‘tangible’) costs and particular technological challenges they have been the preferred means of disposing of waste. of minimising local landfill impacts on the environment, Landfills have long been the preferred means of disposing specifically through containment of contamination and of waste worldwide. This continues to be the case globally then remediation. The Commonwealth Government’s and in Australia, where landfills play a major role in the current National Waste Policy2 follows the waste hierarchy management of waste. There are difficulties in managing [see ‘Trash and treasure: mining landfills for energy and increased waste generation using existing landfill systems. more’ on p. 13], and aims to: The historical, and in some cases, contemporary view that • avoid the generation of waste ‘there is no lack of land to fill’ is increasingly challenged • reduce the amount of waste (including hazardous by more recent developments in the social and physical waste) for disposal landscape. These developments include: • manage waste as a resource • increasing population coupled with increasing consumption per head of population leads to rapidly • ensure that waste treatment, disposal, recovery filling landfills, and and re-use are undertaken in a safe, scientific and environmentally sound manner, and • increasing proximity of settlements to landfills coupled with an increasing understanding of the social, • contribute to the reduction in greenhouse gas economic and environmental impacts of landfill as a emissions, energy conservation and production, water waste management technology is leading to difficulties efficiency and the productivity of the land. in creating new landfills near large population centres. There is no high-level integrated framework or tool to Both factors point to increased costs of landfills as a waste support decision-making on sustainable waste mitigation disposal option through increased transport costs for all strategies. The Institute for Sustainable Futures is waste going to landfills which are sited ever further away undertaking the Landfill Futures project, which has from the sources of wastes. reviewed current sustainability challenges as well as: Individual state and territory jurisdictions are the primary • emerging trends in sustainability frameworks for waste administrators of waste and resource recovery. It is their management role to establish and manage policies and legislation, • technologies and systems for resource recovery and while local government has the primary responsibility for disposal delivering services to the residential community and, in • waste policies at state and federal levels 1 some cases, commercial enterprises as well. Both local • stakeholder views on the future of waste, and government organisations and private companies own and • sustainable initiatives for managing waste as a resource. run waste infrastructure and provide waste collection and transport services.
30 Remediation Australasia Issue 11 2012 FAST FACTS Australia currently disposes of an Some positive recent changes estimated 20 million tonnes of waste to Leaders in this field have identified a around 655 landfills. range of recent ‘high points’ – from the introduction of waste levies in Queensland, During 2006-07, around 48% of Australia’s to changes in how organics and food waste are being treated nationally. Many of these waste was disposed to landfill. recent changes affect local government as waste service providers. Between 2001 and 2007, the volume of waste Waste avoidance and its role in deposited to landfill increased by 12%. policy FURTHER READING Almost all state and territory waste strategies are framed within the waste Environment Protection and Heritage Council 2010, National Waste Report 2010, prepared for the Department of the hierarchy with avoidance at the top, Environment, Water, Heritage and the Arts mirroring the National Waste Policy and Department of Climate Change 2009, National Inventory aligning to COAG’s 1992 National Strategy Report 2007 Volume 2 for Ecologically Sustainable Development. Waste Management Association of Australia 2008, Bioreactor landfill technology – Discussion paper The Australian Capital Territory limits its for information and comment aspirations to ‘reducing’ waste.3 Despite this, there is very little commentary on the role of reduced consumption in achieving this policy objective. Waste industry and government stakeholders are Local government has a major responsibility for interested in costing and pricing, as well as funding waste management.4 The implications of a steadily waste options. People aspire to a future for waste and increasing waste stream for local government are waste management that has strong national leadership significant, as councils continue to try to manage and adequate funding. There are a range of views about the increasing burden of recovering or disposing of the extent to which waste levies (tied to waste disposal materials discarded by households and businesses. at landfills) should be used for waste avoidance/ reduction activities versus general spending. Costs of waste disposal and waste recovery Waste disposal and waste recovery methods have Can integrated resources planning be financial, environmental and social costs. Victoria’s applied effectively to waste? Zero Waste Strategy was backed by a benefit-cost Integrated resources planning (IRP), also known analysis5; however, other states do not appear to be as least-cost planning, is an approach to planning attempting to gain a robust understanding of the for resources that considers both supply-side (e.g. full costs associated with waste management and providing more of the resource) and demand-side mitigation. The relatively low cost of landfill is another (e.g. efficiency) interventions to make sure there is impediment to the development of alternative waste enough to meet future demands. IRP as an established management and mitigation options. While the cost and successful record of use, originally in the US of landfill may continue to be adjusted to encourage energy sector in the 1970s, and more recently in the development of alternatives, levies do not always the Australian water and energy sectors. Its strength achieve the desired results. This may be in part due is in evaluating new supply options and demand- to the failure to factor intangible costs (such as management options on a consistent basis. IRP follows consuming virgin resources) into pricing. a cycle of planning, analysing, developing and selecting
FURTHER READING 1 WME 2011, Waste Industry Report 2011/2012. Chapter 3 Department of the Environment, Climate Change, Energy 4 Commonwealth Waste Management Frameworks. and Water (DECCEW) 2010, ACT Sustainable Waste www.wme.com.au/insidewaste/downloads/ch.4_ Strategy 2010-2015, Australian Capital Territory, Canberra. IndustryReport_Preview.pdf 4 Australian Local Government Association 2008, Inquiry 2 Environment Protection and Heritage Council (EHPC) into the Management of Australia’s waste streams, Canberra, 2009, National Waste Policy: Less waste, more resources, Australia. Department of the Environment, Water, Heritage and the Arts.
www.remediationaustralasia.com.au 31 options based on least-cost and There is a need for decision- sustainability criteria. “At federal and state making frameworks that can adequately assess The next step involves implementing government levels, existing different waste mitigation a portfolio of waste minimisation and management options (demand reduction) and waste policy poses a against agreed objectives, management (e.g. increasing landfill strong challenge for in specific contexts. As the supply) options to achieve supply- costs and impacts for all demand balance, followed by addressing fragmentation forms of waste disposal monitoring and evaluation as part of and mitigation become an adaptive management philosophy. in the waste system.” better understood, the IRP can also be linked to costs and objectives of deliberative processes for agreeing on Data availability is a key concern waste policy will need to goals and generating and selecting for Australia, as data at all levels be better integrated. The industry options, to assist with reconciling of government are either poor, also needs to better understand trade-offs and planning under not publicly available or not being community expectations regarding uncertainty. Although IRP has been used for decision making. Some levels of service, manage the risks successfully applied in the Australian levels of government may have entailed in more sophisticated waste water sector and internationally in reservations about using comparative management/mitigation systems, the energy sector, it has not yet been data to rank performance across minimise greenhouse gas emissions, applied in systems with the variety jurisdictions (either across all local and develop the expertise required of materials currently involved in the governments within a jurisdiction to achieve sustainability across the waste system. or across states and territories in waste, energy and land-use planning Australia). nexus. Possible information gaps At federal and state government Conclusions High-quality, robust and relevant information is needed to help the levels, existing waste policy Australian cities and towns face poses a strong challenge for sector make decisions concerning considerable challenges to mitigate these emerging challenges. Effective addressing fragmentation in the and manage growing waste waste system. This is evident waste management and mitigation production from an increasing, planning in Australia require the when observing inconsistencies ever-consuming populace. To tackle in waste-management knowledge collation and analysis of strategic these challenges, the waste industry data and a long-term view to and expertise, and differing levels – together with stakeholders across of infrastructure constraints to inform an adaptive decision making the production consumption chain – process, as well as acknowledge innovation in waste management, must adopt new supply-and-demand across states and territories. the constraints of the past. strategies to reduce waste generation, Importantly, waste reduction and Discussions about the relative improve waste management and waste management infrastructure merits of landfill, waste-to-energy protect our environment, all in must be considered together, as technologies and composting a transparent and cost-effective sister strategies to meeting the technologies for alternative waste manner. goal of managing material flows in management are taking place This research challenges the sustainable settlements. in a rapidly changing technical effectiveness of the objectives and environment, often with limited targets set by state and territory This paper is based on findings of independent guidance. This is governments, without detailed the CRC CARE-funded Landfill particularly clear with respect to implementation plans informed Futures project undertaken by the local government, which must by consideration of the real costs Institute for Sustainable Futures, continue managing a steadily growing in involved in the day-to-day which were presented under the title waste burden while responding management of waste. It observes Waste Futures: project overview and to community expectations about that the economic and financial preliminary findings to the Australian public health standards and key constraints on local government are Centre of Excellence for Local environmental issues. not always well represented in the Government researcher’s forum at There are inconsistencies in waste objectives and target setting of state University of Technology, Sydney on data, standards and definitions government policy. 15 December 2011. across Australia’s jurisdictions.
FURTHER READING 5 Allen Consulting Group, 2003. Benefit–Cost Analysis of Victoria’s Towards Zero Waste Strategy, Report to Eco-Recycle Victoria.
32 Remediation Australasia Issue 11 2012 Department of Industry Innovation, Science, Research and Tertiary Education
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Cleantech Industry Capability Teams are targeting five different customer groups:
Manufacturing Built environment and Mining/resource and minerals processing infrastructure Developing countries Food and beverage production and processing
To register your interest to participate in the Cleantech Capability Teams, download and complete the registration form on our website: www.auscleantech.com.au/ACT_Cleantech-Capability-Teams.html BROWNFIELDS REMEDIATION
Perception of brownfield sites: Myth or reality?
Connie Susilawati and Kelsey Thomas, Queensland University of Technology
The scarcity of large parcels of usually semi-rural property that is and additional housing options, land in well-serviced areas is undeveloped except for agricultural reduced commuting times, a one motivator for redeveloping use).2 reduction in public health issues, industrial or commercial property and improvement in the quality Brownfield site redevelopment is that is abandoned or underused of life through additional services often put in the too-hard basket and often environmentally and infrastructure due to new by private developers who would contaminated – so-called development and renewal. prefer to develop greenfield sites, brownfield land. Poor industrial which are perceived to incur lower However, the historical waste disposal practices caused costs and risk levels. This stigma has connotations can mean that the by industrial activities including been experienced at some brownfield public perceives brownfield sites gas works, factories, railway land sites where contamination issues are as contaminated, which can be a and waste tips have contributed to perceived by the public but don’t major barrier for redevelopment – many instances of contaminated actually exist. even when this is not necessarily land identified as brownfield sites. the case. Perhaps this recognition It is estimated there are between In this article we examine public of negative public perception of 10,000 and 160,000 brownfield opinion and perceptions of brownfields sites has had some sites in Australia, with Queensland brownfield sites, including findings impact on the composition of the accounting for around 4000 of from a public survey. We also current South-East Queensland these.1 look at the problems, and the Regional Plan 2009-2031, in positive and negative impacts, of Despite the range of definitions which the words ‘sustainable remediating brownfield sites. available for the concept of development’, ‘urban renewal’, brownfield sites, there is a stigma The redevelopment of brownfield ‘infill development’, ‘contaminated attached to that term – meaning sites offers such economic, social land’ and ‘greenfields’ appear that the public perceives the site as and environmental benefits to have been used instead of risky. Further, the redevelopment as the renewal of suburbs and the word ‘brownfields’. The of a brownfield site is perceived as centres, creation of new jobs, the most common definition of costlier and riskier than working introduction of new investment sustainable development, as used with a greenfield site (piece of into the area in the form of new by the Queensland Department development, increased new of Infrastructure and Planning in the current version of that regional FIGURE 1 Risks plan, is ‘development that meets the needs of the present without compromising the ability of future DEGRADATION OF generations to meet their own 13% 12% CHARACTER OF needs’. 13% THE AREA It is important to note that ENVIRONMENTAL ‘brownfield’ does not necessarily 1 2 mean ‘contaminated’, and that 62% 3 DAMAGE 4 contamination for some brownfield HEALTH RISKS sites are issues of perception, not reality. As well as dampening the OTHER enthusiasm for redevelopment, this leads to the same negative
34 Remediation Australasia Issue 11 2012 TABLE 1 Level of concern demonstrated by people living in redeveloped brownfield areas. Respondents UNAWARE Respondents AWARE 0 = no concern; 10 = grave concern. of nearby brownfields of nearby brownfields Redeveloped 4.33 3.65 brownfield site Redeveloped 6.33 3.75 contaminated site
connotations associated with a (DEHP). DEHP provides advice When a site is located in a built-up site that is actually contaminated. on legislation and technical urban area, constraints are placed Additionally, the communication requirements, reviews contaminated on the type of development due to about the existence of site investigations and approves site the site shape, access to the site, the contaminated land sites and management plans. greater town planning restrictions, proposed remediation solutions and any restrictions due to To reduce the level of risk for land are very complex, and has to be existing infrastructure maximum buyers, potentially contaminated balanced between procedure and allowances. Redevelopment can also sites are registered with the outcomes. place increased strain on existing Environmental Management infrastructure and public services, Register (EMR) and Contaminated erode green space in the case of Brownfield redevelopment Land Register (CLR) by the vacant sites and infill development, Queensland government; DEHP Queensland first legislatively and negatively impact neighbours maintains this register. Registration addressed the issue of brownfield through noise and air pollution. on the EMR is required for land and contaminated land in 1991 The redevelopment of a brownfield that is (or has been) used for with the Contaminated Land site can negatively and positively notifiable activities (activities that Act, which led to the Queensland change the amenity, and values of are likely to cause contamination) Environmental Protection Act the suburb. 1994 with the aim to ‘protect or has been contaminated by a Queensland’s environment while hazardous contaminant. DEHP One such example is the Brisbane allowing for development that states that the ‘registered sites pose Urban Renewal Project, which was improves the total quality of a low risk to human health and initiated in 1991 to renew urban life, both now and in the future, the environment under the current areas in Brisbane. A combined in a way that maintains the land use’, and that ‘entry on the area of approximately 730 hectares ecological processes on which life EMR does not mean the land must covering the suburbs of Fortitude depends (ecologically sustainable be cleaned up or that the current Valley, New Farm, Teneriffe, development).’ The Queensland land use must stop’. DEHP states Newstead and Bowen Hills was Environmental Protection Act 1994 that registration on the CLR is earmarked by the Brisbane City places great emphasis on managing for ‘proven contaminated land Council for renewal. which is causing or may cause the environment and, in chapter 7 The areas have transformed serious environmental harm… of the act, outlines the management from declining, outdated and when scientific investigation shows of known contaminated sites unattractive precincts to vibrant, it is contaminated and action and potentially contaminating diverse inner urban areas of needs to be taken to remediate activities in Queensland to increasingly high amenity. The or manage the land’. Scientific prevent environmental and health majority of works are complete, but investigations and site management risks. Management is led by the not all areas are finished. Department of Environment plans are carried out by industry and Heritage Protection professionals, and reviewed by DEHP.
FURTHER READING 1 Brebbia, CA 2008, Brownfields IV: Prevention, Assessment, Rehabilitation, Restoration and Development of Brownfield Sites, Portugal, WIT Press. 2 Johnston, N 2010, ‘Unlocking the productive potential of brownfield sites’,Remediation Australasia, Issue 3.
www.remediationaustralasia.com.au 35 TABLE 2 Purchase and rent decisions based on EMR/CLR checks Respondents UNAWARE of Respondents AWARE of nearby brownfields nearby brownfields Performed Did not perform Performed Did not perform a check a check a check a check
For purchasing 26 4 16 0
For renting 5 25 7 9
Negative impacts of brownfield sites Brownfields Vacant, unused brownfield sites (whether contaminated or only areas of land previously used perceived as contaminated) contribute to a loss in property value, for industrial or other purposes loss of jobs, loss of tax revenue, a threat to public health and the available to be redeveloped environment, and potential liability for the contamination.2 for alternative purposes During development, blow-outs in expected cost and time can be (Queensland Government) anticipated, due to the remediation of the contamination, and the potential for lawsuits and liability relating to the remediation of Contaminated the site.2 A site located in a built-up urban area can constrain the type of development possible, due to the site shape, access to the land site, greater town planning restrictions, and existing infrastructure land so damaged by industrial maximum allowances. Brownfield redevelopment can also place or other development that it increased strain on existing infrastructure and public services, is incapable of beneficial use can erode green space in the case of vacant sites and infill without treatment development, and negatively affect neighbours through noise and air pollution. The lack of redevelopment of a brownfield site can Infill development diminish a suburb’s amenity and property values.2 new development that occurs within established urban areas Positive impacts of the re-development of brownfield where the site or area is either sites vacant or has previously The redevelopment of brownfield sites has positive impacts for been used for another urban both the surrounding society and the developer. Such a project can purpose. (Queensland improve a suburb’s amenity and property values. Renewing older Government) suburbs and past industrial areas is high on government planning agendas. It is already happening in Brisbane and southeast Urban renewal Queensland, with exceptional results for society and developers regeneration of disused alike. In the United States, redevelopment of brownfield sites is industrial or government land encouraged by state-led voluntary brownfield clean-up programs. which may be suitable for residential development Public perception A survey of 47 respondents who work in the Brisbane central Greenfield sites business district aimed to capture the general population’s areas of undeveloped or ‘raw’ perception of brownfield sites and redevelopment in southeast land free from contamination… Queensland. Definitions (summarised from the literature critique) that are suitable for urban of ‘brownfield’ and ‘contaminated land’ were given to respondents development. to ensure they had a clear understanding of the terms. Queensland Department of The majority of the population were not aware of any brownfield Infrastructure and Planning sites near their residence, and those who were aware showed very
36 Remediation Australasia Issue 11 2012 TABLE 3 Contamination/remediation actions and their effect on decisions to live on a redeveloped site Respondents UNAWARE Respondents AWARE of of nearby brownfields nearby brownfields
Did affect the decision 24 (52.17%) 14 (30.43%)
Did not affect the decision 6 (13.04%) 2 (4.35%)
little concern about their proximity to the site. The their decision to live on a redeveloped contaminated majority of respondents believed that petrol stations site (see Table 3). were the most likely source of brownfield status. Only around two-thirds (65%) of respondents were Respondents’ greatest concern was environmental unaware of any contaminated land near where they damage, over and above degradation of character of the live. There were slightly different attitudes between area and health risks (see Figure 1). Participants who awareness related to decisions made for purchase were aware of existing of brownfield sites near their and decisions made for renting. Those who were home showed a lower level of concern, regardless of aware of any contaminated land indicated that any whether they live on a redeveloped brownfield site future decision to purchase their primary residence (contaminated or not). However, participants unaware in future would include a check of the EMR or CLR. of a nearby brownfield site were more concerned about However, people were not overly concerned about living on a redeveloped brownfield site, particularly such checks if they intended to rent. one that had been contaminated (see Table 1). Table 2 illustrates the number of respondents who made Unfortunately, few people were aware of the purchasing or rental decisions based on an EMR or existence of contaminated land, or knew how to CLR search. minimise their risk by checking the EMR or CLR. Redevelopment of “The redevelopment of brownfield sites has brownfield sites is often drawn out when it comes positive impacts for both the surrounding society to approving a remediation and the developer. Such a project can improve management plan and removal from the CLR. a suburb’s amenity and property values.” More realistic timelines may be achieved by gathering Asked if they would conduct an EMR or CLR search evidence of turnaround time and general fees if planning to purchase a property for use as a primary through initial interviews with builders, developers residence, most respondents (91%) said they would and consultants, as well as a DEHP official. perform such a check. The 9% who responded ‘no’ In summary, a majority of respondents (65%) were were unaware of nearby brownfield sites. Around unaware of any brownfield sites near their homes, three-quarters (74%) of respondents indicated that but those who knew of such sites were less concerned they would not perform such a check on property about the idea of living on them. People looking to they planned to rent. This discrepancy was expected, purchase a primary residence were more motivated as renting is generally viewed as a short-term form of to investigate contamination than potential renters. accommodation posing a shorter exposure period to However, relatively few people were aware of the the risks from contamination. existence of contaminated land or how to minimise their risk by checking the registration through EMR/ Contamination and remediation CLR. It is likely that a better-informed public would Most (83%) respondents said that the type of lead to less contentious decisions at all stages, from contamination and remediation action would affect developing a property through to buying a home.
www.remediationaustralasia.com.au 37 Research RoundUp Research Roundup aims to keep you up-to-date with current research on environmental contamination assessment and remediation in Australia. By keeping content succinct and focusing on particular projects, Remediation Australasia makes it easier for you to find the time to read about areas which are relevant to you. In this issue, the focus is on CRC CARE funded projects. CRC CARE’s second term of operation commenced in July 2011, and the research programs have an increased focus on helping to develop uniform national standards for assessing and remediating contamination. The outputs from the research programs will fill knowledge gaps and allow adoption of remediation that balances health and environmental protection with economic and social considerations. With this in mind, the CRC has funded the following projects:
Environmental risk assessment of nanomaterials for soil and groundwater remediation Contaminant transport by naturally occurring nanoparticles (i.e. colloids) has been identified In recent years as a key process underlying the unexpected movement of low-solubility environmental contaminants away from their source. It is likely that this type of unwanted transport may be further facilitated by the addition of manufactured nanomaterials to the environment. This project aims to reduce the uncertainties regarding the potential side effects of manufactured nanomaterials designed for use in soil/groundwater remediation. The project will focus on nanomaterials already employed or being developed specifically for remediation (e.g. nanoscale zerovalent iron and pther nanomaterials close to the commercialisation stage). The knowledge gained will support the design of effective yet sustainable nanomaterials; it will also help remove impediments to commercialisation by strengthening industry and regulator confidence, and ensuring that inadequate risk assessment does not disrupt market growth. The outputs will increase certainty that the target technologies are safe for commercial scale application.
Aggregate structure before flocculant addition. 1 & 3: Without Ultrasonic equipment ultrasonic pre-treatment. 2 & 4: With ultrasonic pre-treatment In the last decade, new high power ultrasonic treatments to improve thickening in food 1 2 technology and in industrial and sewage wastes have been highly successful. This technology has not yet been applied to mineral processing concentrates and wastes but offers major potential in this field. A project with Rio Tinto, UniSA, High Power Ultrasonics P/L and CRC CARE investigated using ultrasonic treatment to enhance thickener performance 3 4 in increased settling rates, consolidation rates, underflow solids density and water recycle with tailings containing significant clay content. Tests showed that settling rates at the same flocculant dosage could be increased by up to 40% and underflow solids densities by 20% for both commercial kaolin and real high-clay tailings. On these results translated into practice, estimates at one Rio Tinto mine would give 3.5 gigalitres p.a. water saving worth more than A$5.5 million to that operation. Dr Jason Du working with Prof. Roger Smart identified, by understanding the changes in aggregate structure of the clays, how and where in the thickening sequence the ultrasonics need to be applied for maximum benefit. This is critical to effective dewatering and now
protected in the joint patent with CRC CARE.
38 Remediation Australasia Issue 11 2012 Arsenic bioavailability, biomagnification, detoxification in aquatic systems and eco- toxicological validation Besides soil contamination, aquatic systems (particularly freshwater bodies) have been contaminated by arsenic in many countries from natural and anthropogenic sources. Arsenic is one of the deadly toxic elements ubiquitous in the environment; its toxicity is associated with its speciation and concentration.The Mole River mine is a well-known point- contamination source of arsenic in Australia. Mining and processing of arsenopyrite ore at several localities in northern NSW and southern Queensland in the 1920s and 1930s have resulted arsenic contamination of freshwaters in these areas. Aquatic microorganisms contribute to the occurrence of thermodynamically unstable arsenite and methylarsenic compounds in natural waters, which are then converted to less toxic organoarsenic compounds. In order to provide a complete toxicological assessment of arsenic detoxification to limit its toxicological impacts in aquatic systems, it is thus important to assess the persistent forms of arsenic and their bioavailability. In natural aquatic systems, phytoplankton plays an important role in the detoxification of highly toxic inorganic arsenicals to less toxic methylarsenicals and organoarsenic compounds such as arsenosugars, arsenobetaine. This project will provide validation of arsenic detoxification mechanism (metabolism of highly toxic methylarsenicals to organoarsenic compounds) by phytoplankton as an effective remediation technique, and thus, having potential for the advancement of bioremediation technology. The specific objectives are to- (i) characterize arsenic pollution and its biological impacts in Australian aquatic systems, (ii) investigate the bioavailability and trophic transfer of arsenic in aquatic food webs, (iii) calibrate the response of relevant dominant phytoplankton to arsenic in relation to the concentration and chemistry, develop an in situ bioassay procedure to evaluate arsenic toxicity using phytoplankton, and assessing the competence of As-detoxification by calibrated phytoplankton, and (iv) arsenic uptake in Australian native aquatic plants grown in contaminated aquatic systems to evaluate their potential for phytoremediation.
Developing environmental experts.
CRC CARE supports the growth of highly qualified and suitably trained researchers and decision makers in environmental risk assessment and remediation through:
PhD and Honours research opportunities workshop training for environment industry professionals linkages with other industry peak bodies focusing on end user needs a suite of publications and guidance documents hosting the biennial ‘CleanUp’ industry conference
Contact CRC CARE for further information. Cooperative Research Centre for Contamination Assessment and Remediation of the Environment
www.crccare.com
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Remediation Australasia is a quarterly magazine Issue 8 2012 Issue 9 2012
for the Australasian remediation industry. Issue 10 2012 Remediation Australasia includes a range of full technical articles, REMEDIATION New methods for regulator updates, case studies, training events, publications, and news DeconstructingPROCESSES: IDENTIFYING DUST The importance of paper mills: TOXICITY community consultation relating to new technologies and research developments, keeping the CLEANING UP reader ahead of the public debates and scientific advances within the THE MERCURY BIOREACTIVE ORGANOCLAYS A new technology for industry. It informs people working in the remediation industry about new environmental remediation research and outcomes that may impact on their business, and helps
USING LIDAR TO them to better respond to the challenges of dealing with contamination. POWER A NATION Using lidar and wind power for Kenya’s energy needs To subscribe, fill out the form below and return it to us, or email us with
CONTAMINATED SITE LAW AND POLICY your details. Updates on recent QUANTIFYING changes in Australia TPH IN SOILS MINE DUMPS AND Measurement quality and novel analytical methodologies SITE HISTORY Remediation usingLANDFILLS the giant REVIEWS reed WhatArundo data donax should you be REDUCING METHANElooking for, and where? USING SITE HISTORY EMISSIONS Transforming animal waste INSURANCE FOR INFORMATION ENVIRONMENT How to make the most of it SUBSCRIPTION FORM How much is it worth?
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October 3 Environmental management plans – Who 22 Petroleum vapour intrusion (PVI) Assessment reads ALGA / Sydney training course www.landandgroundwater.com/#/events/calendar CRC CARE & ALGA http://bit.ly/PVIinvitation 10 Introduction to environmental site assessment (CPD training, module 8) 23 – 26 Australian Groundwater Modelling ACLCA / Melbourne School using GMS www.aclca.org.au/cms-events/index.phps SRIT / Perth www.srit.com.au/course_details.php?id=32 10 – 12 Occupational Health and Safety 3 Day Course 24 Petroleum vapour intrusion (PVI) Assessment ACLCA / Melbourne training course www.aclca.org.au/cms-events/event-registration.phps CRC CARE & ALGA http://bit.ly/PVIinvitation 17 Olympic Dam expansion (Groundwater issues/innovations/etc) 26 Petroleum vapour intrusion (PVI) Assessment ALGA / Adelaide training course www.landandgroundwater.com/Industry%20Calendar.html CRC CARE & ALGA http://bit.ly/PVIinvitation 17 SuRF and sustainable remediation - The great debate 29 Oct – 1 Nov Groundwater modelling using ALGA / Melbourne ArcHydro GW www.landandgroundwater.com/Industry%20Calendar.html SRIT / Perth www.srit.com.au/course_details.php?id=41
November 13 Expert witness seminar – State 21 Landfill BEPM administrative tribunal. Neutral expert within? ALGA / Melbourne ALGA / Perth www.landandgroundwater.com/#/events/calendar www.landandgroundwater.com/#/events/calendar TBC Introduction to environmental site 14 – 16 Sustainable Remediation 2012 assessment (CPD training, module 8) EURODEMO+, US EPA & CL:AIRE / Vienna ALGA / Melbourne www.umweltbundesamt.at/sustainable_remediation2012 www.landandgroundwater.com/#/events/calendar
15 A look back on the first year of theNational Environmental Standard for Managing Contaminants in Soil ALGA / Auckland www.landandgroundwater.com/#/events/calendar
December 2 – 7 Joint ASSSI and NZSSS Soil Science Conference: Soil Solutions for Diverse Landscapes ASSSI & NZSSS / Hobart www.soilscience2012.com/
www.remediationaustralasia.com.au 41 Publications Update This section contains publications that have been published in the last 3 months (since the last edition of Remediation Australasia). The publications may originate from research institutions, regulators or industry groups. Let us know if you have any appropriate publications (no promotional material) for inclusion by emailing [email protected].
Use of inorganic and Gasification of biomass organic wastes for in situ micron fuel with oxygen-en- immobilization of Pb and Zn riched air: Thermo-gravimet- in a contaminated alkaline soil ric analysis and gasification Zhou, Haynes & Naidu 2012, in a cyclone furnace Cheng, Environmental Science and He, Xiao, Hu, Liu, Zhang & Pollution Research, vol. 19, iss. Cai 2012, Energy, vol. 43, 4, pp. 1260–70. iss. 1, pp. 329–333.
Degradation of p-nitrophenol by immobilized Urinary excretion of bilirubin oxidative cells of Bacillus spp. isolated from soil metabolites in arsenite-treated mice Sreenivasulu, Megharaj, Venkateswarlu & Arthur, Ng, Lang & Abu-Bakar 2012, Naidu 2012, International Biodeterioration & Journal Toxicological Sciences, vol. 37, Biodegradation, vol. 68, pp. 24–27. iss. 3, pp. 655–661.
Comparison of the effects Optimal identification of of conventional organic groundwater pollution sources amendments and biochar on using feedback monitoring the chemical, physical and information: A case study microbial properties of coal fly Chadalavada, Datta & ash as a plant growth medium Naidu 2012, Environmental Belyaeva & Haynes 2012, Forensics, vol. 13, iss. 2, pp. Environmental Earth Science, vol. 140–153. 66, iss. 7, pp. 1987–1997.
Effect of synthetic dairy factory effluent Metabolism of bilirubin by human cytochrome P450 2A6 containing different acids (H3PO4, HNO3 Abu-Bakar, Arthur, Wikman, Rahnasto, Juvonen, and CH3COOH) on soil microbial and Vepsäläinen, Raunio, Ng & Lang 2012, Toxicology and chemical properties and nutrient leaching Applied Pharmacology, vol. 261, iss. 1, pp. 50-58. Liu & Haynes 2012, Biology and Fertility of Soils doi: 10.1007/s00374-012-0678-1. Bioavailability of lead in contaminated soil depends on the nature of bioreceptor Organoclays reduce arsenic bioavailability Ming, He, Lamb, Megharaj & Naidu 2012, Ecotoxicology and bioaccessibility in contaminated soils and Environmental Safety, vol. 78, pp. 344–350. Sarkar, Naidu, Rahman, Megharaj & Xi 2012, Journal of Soils and Sediments, vol. Interactions between Ca, Mg, Na and K: Alleviation of 12, pp. 704–712. toxicity in saline solutions Kopittke 2012, Plant Soil, vol. 352, pp. 353–362.
42 Remediation Australasia Issue 11 2012 Enhance your career with a research degree in environmental remediation.
CRC CARE is offering three PhD scholarships, valued up to $28,500 p.a. (tax free) for three years, for potential candidates to undertake projects focussed on light non-aqueous phase liquids (LNAPLs).
Australian petroleum industry and regulatory agencies wish to support improved understanding of the sustainable remediation of LNAPLs, such as petroleum fuels in groundwater environments. Such improved understanding will be developed through better field-scale quantification of the effectiveness of remediation strategies in removing LNAPLs from aquifers, thereby reducing exposures and risks. There are currently 3 research projects available:
Field evaluation of the inter-comparison of petroleum (LNAPL) remediation technology efficiencies in complex fractured and/ or porous media Multiphase modelling of petroleum (LNAPL) remediation options in aquifers with complex geologies Quantifying the transient risk due to petroleum (LNAPL) removal from impacted sites
The PhD students will work closely with project investigators, consultants and other specialist staff on this well funded, industry linked project. The projects will be conducted at CSIRO Land and Water, Floreat Western Australia in partnership with the University of Technology Sydney (UTS), and jointly with industry partners where field investigations are undertaken and applications tested.
For further project related information, please contact: Colin Johnston Robert McLaughlan CSIRO Project Leader UTS Supervisor +61-(0)8-9333 6328 +61-(0)2-9514 2614 [email protected] [email protected]
Visit www.crccare.com for more information on these and other scholarship opportunities.
A safer, cleaner environmental future www.crccare.com