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  • https://au.linkedin.com/pub/dr-georgina-davis/52/454/511

In January 2015, Queensland began exporting Coal Seam Gas (CSG, otherwise known as coal bed methane) to Asian markets. The volumes expected with these exports are expected to realise 1400BCF in 2017 alone and combined with gas (including off-shore conventional gas) developments in Western Australia and the Northern Territories are expected to ensure Australia’s elevation to be the world’s leading exporter of Liquefied Natural Gas (LNG) by 2020.

The CSG industry has strongly embraced new technologies (including GRE through to polypipe in gas production operations), dealt with unknown challenges in geology and has shaped its own regulatory environment which has, in part, evolved the industries development and responded to community concerns.

Last year, there was increased concern surrounding the impacts from the disposal (or indefinite storage) of salt produced from CSG activities in Queensland. On 16 February, these concerns hit the front page of Queensland Country Life reflecting the anxiety within the agricultural community. The source of this concern was the approval by Western Downs Regional Council and the State Government of a salt disposal facility near Chinchilla; and the proximity of this site to critical surface water resources and the potential impacts to groundwater.

The current gas industry generates a number of by-products including, but not limited to, fracking fluids, drill muds, CSG waters and brine. Under the previous state government, the status of some of these waste products was amended, to remove them as ‘regulated waste’ under a beneficial use approval. This amendment meant that additional tracking, transport and disposal requirements now only apply to strongly saline CSG water, and brine concentrates. Whilst this resulted in a reduction in regulatory burden (and financial cost) for the majority of CSG waters, and indeed the gas industry, such measures do not necessarily provide confidence to the community.

The quality of CSG water quality varies greatly, however it is generally accepted to include varying concentrations of salts and other minerals. CSG water is currently reused for a number of purposes that have been deemed by the Department of Environment and Heritage Protection to be beneficially used for environmental releases, existing or new water users, and existing or new water-dependent industries. One of these water-dependent uses has been agriculture, ranging from stock watering to cropping and irrigation.

Salt extraction from reverse osmosis from ‘associated waters’, produced as the coal seams are depressurized to enable the flow of gas, has also allowed for the beneficial use of water. The treatment of CSG water using desalination technologies for example results in brine and, ultimately, salt residues that must be appropriately managed under a ‘Salt Management Plan’. The concentration and composition of salts depending on the characteristics of the CSG water and the treatment process.

The Coal Seam Gas Water Management Policy (2012), requires that saline waste is managed in accordance with the following two priorities, that firstly brine or salt residues are treated to create useable products wherever feasible; and secondly, if no markets are available once fully investigated, disposing of the brine and salt residues in accordance with strict standards that protect the environment. To date, there has been very little development of credible markets for usable products, not that the salt is unsuitable for a range of applications (from pool salt to hide curing in the leather industry), but reflecting the regional and remote locations in which the salt is generated and the economic constraints of supplying/transporting a low value product to far away markets.

As the CSG industry has expanded, there also has been a realization that the volumes of water and, in turn, salt and brine arising from the CSG sector has been significantly below early predictions which was based on modelling of 2-phase flow and included a high level of conservatism.

  2008-2012 predictions Updates for 2015-2016
Wells 20-25,000 18,000
Water plateau 120-300 GL/Yr ~80GL
Salt 30-60Mt ~5.5Mt

Source: Data collected by the Centre for Coal Seam Gas at the University of Queensland

These revised-down estimates and actual generations, coupled with the deregulation of some CSG waste streams, have had significant (negative) impacts on the waste management enterprises who, in the early days, provided new treatment infrastructure and increased vehicle fleets based on the expectation of high volume, high-hazard wastes over the life-time of the CSG industry. These early overestimations also resulted in the over-capacity of water treatment by the CSG companies themselves through to heightening community concerns.

Environmental Approvals (EAs) for both hazard dams and waste disposal have now also been granted to the major CSG proponents, with the storage and evaporation infrastructure engineered to meet on-site/in-situ disposal requirements if required (subject to no end market uses being developed for the brine and salts).

In future, the role for external off-site management of wastes for this industry appears to be restricted, limiting opportunities for the traditional waste management sector – especially for those only offering options at the bottom of the waste hierarchy.

Will Queensland’s newly emerging gas sectors offer more opportunity for the waste management sector? Possibly, but only to those companies offering high technology solutions far up the waste management hierarchy.   If the new gas sectors outlined in the Department of Natural Resources and Mines ‘Queensland Gas Supply and Demand Action Plan: Discussion Paper’ (November 2016) see operational roll-out; their regulation is likely to be similar to the existing CSG industry with government seeking to expedite the tenure, licencing and extraction phases. Undoubtedly, these gas industries will produce more complex and potentially hazardous wastes and one would anticipate that regulation (and technologies) would manage them responsibly and sustainably. Indeed, some of the fracking fluids will pose new risks and will require new treatment opportunities.

In considering this future, I always reflect on the guiding principles of environmental policy set out in the Intergovernmental Agreement on the Environment, including the ‘Precautionary Principle’, ‘Intergenerational Equity’ and the ‘Conservation of Biological Diversity and Ecological Integrity’.  This Agreement was designed to provide a mechanism to align the decision making between States and Federal Government, and to facilitate better environmental protection.

Within this agreement, Section 3.5.1 states the precautionary principle as –

Where there are threats of serious or irreversible environmental damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation. In the application of the precautionary principle, public and private decisions should be guided by:

  1. careful evaluation to avoid, wherever practicable, serious or irreversible damage to the environment; and
  2. an assessment of the risk-weighted consequences of various options”.Whilst there is always a perceived tension between development and the protection of the environment, we must take care to unduly ‘pick winners’, particularly where scientific evidence and precedent does not exist.  Such situations are exactly where the precautionary principle must be considered. It is also where clever recovery technologies and steadfast waste management businesses can provide real value.

Whilst there is always a perceived tension between development and the protection of the environment, we must take care to unduly ‘pick winners’, particularly where scientific evidence and precedent does not exist.  Such situations are exactly where the precautionary principle must be considered. It is also where clever recovery technologies and steadfast waste management businesses can provide real value.