Monday 28 April 2014

Clarence-Moreton Basin CSG Bioregional Assessment with some Philosophy

I was fortunate enough to be invited to a short presentation on hydrology and coal seam gas in the Clarence-Moreton basin last week. It was particularly good, in part, since lunch was provided and one of the presenters from the CSIRO ended up being someone I knew but had not seen for nearly a year. The topic of the presentation was an assessment that has recently commenced on the effects of coal seam gas (CSG) on water resources. Alas, it is something that the media has all but ignored. So a bit of information and a bit of philosophy in the blog post today!

This year a large investigation (a bioregional assessment) into all the possible effects of CSG on water commenced in earnest. It is a project funded by the Federal Government with many scientific project partners including the CSIRO. The project is based exclusively in the first case, on the compilation of scientific information. It is at arms-length from government and politics, so it is entirely technical. Therefore, this assessment is something which I personally find interesting and feel is of great value. The project scope has been set up by the Independent Expert Scientific Committee on Coal Seam Gas and Large Mining Development. The committee was established in 2012 and works under the authority of the Environmental Protection and Biodiversity Conservation Act 1999. A link to the CSIROs summary of its involvement can be found here.

The Clarence-Moreton basin bioregional assessment itself is one part of many bioregional assessments in numerous Australian coal basins. These assessments are themselves divided up into many different components including hydrogeology, ecology, ecotoxicology, environmental protection and many others. The presentation that I attended was specifically related to the hydrogeological modelling that is being developed. It briefly covered the different data sources and data limitations that were going to go into the modelling. It was good to see the thoughtfulness and consideration given to all the hydrogeological issues. Sometimes just figuring out what needs to go into a model is very hard in itself… but by far the hardest task is making sure the modelling reflects the real world. This is because of the varying amounts of "weighting" required to each of the input variables.

However, one of the things that saddens me is the lack of media time this assessment has been given. Many people are concerned that not enough is known about CSG activities in our region or in Australia or even more broadly, around the world. The media tends to focus on the conflicts that are occurring and not on the advances in technical knowledge that will lead to better decision making in the near future. The media does not seem to like reporting on things that we are learning but instead increases the confusion about matters that could lead to social conflict. Conflict, not cooperation seems to sell newspapers these days.

I was also a little saddened by some questions that were asked of the CSIRO presenters. One (Environmental Economics and Policy Academic!) asked whether it was ethical to undertake this assessment because it may lead to a CSG development being regarded as “safe”. To consider an increase in human knowledge of the world in which we live un-ethical is a big worry for me. Especially from a senior academic. In many ways it questions the very basic concepts of scientific endeavour. Having a scientific background, I feel we should not avoid learning something new because the facts that may arise could potentially contradict with a pre-determined world view. We are of-course moving from science to philosophy. I know my philosophical motives in life are to use knowledge to give the best outcomes for the environment and people that live in our region.

So, to end on this philosophical note: I recommend thinking about the knowledge that we have and how we use or ignore it. The media practice of looking only at conflict and dumbing down its stories on scientific and technical matters is well entrenched. I’m starting to genuinely believe that the media is making it harder to distinguish between facts and opinions purely in the media’s self-interest of creating a story to make money from. Recognising this is helpful to understanding where scientific information can guide us in the right decisions, as such I provide here a link to an ABC presentation on the media by an excellent modern day philosopher (one of my favourite non-science authors) Alain De Botton.

Monday 7 April 2014

Where Does the Groundwater Flow?

There has been renewed interest in groundwater resources in the Northern Rivers of late. In part this is due to peoples concern about "unconventional" gas exploration and production in the area. Surprisingly, less known is the release of Rous Water's Future Water Strategy which includes groundwater as first on the list for new water sources. Rous Water is a major bulk drinking water supplier in the region. I've previously covered an area within the coastal sands groundwater source called the Woodburn Sands but this was a cursory look and I'd not covered where the groundwater actually goes.

Groundwaters do not exist as an underground lake in our region
Image courtesy of International Association of Hydrologists
Groundwater is often seen as a bit of an unknown, a black box, or some kind of underground lake (see the cartoon). It is quite difficult to observe and therefore people can get the wrong idea of what goes on underground.

One area that is not understood is that groundwater usually discharges somewhere. Sometimes groundwater discharge is obvious through springs. But where it intersects with permanent surface water it is much less obvious. The Evans Head area is a good example of where discharge from the Woodburn Sands aquifer and broader Coastal Sands aquifers is concealed.
Spring-fed creek on Chinaman's Beach.

While walking along Chinaman's Beach south of Evans Head during a recent long dry spell, I couldn't help notice the dark coloured water flowing over parts of the beach. This is one of those discharge areas I'm talking about (most people might be more used to seeing freshwater flowing over a beach from contaminated urban stormwater drains). The coastal sands above Chinaman's Beach holds groundwater and slowly discharges it at the beach. The dark colour of the water is from dissolved humic matter from coastal vegetation soaking into the sand. Tasting the water it was apparent there was no salt in it and understanding the groundwater area I knew it was clean. The springs I observed on Chinaman's Beach were obvious areas of groundwater discharge. The vegetation in the springs was lush and clearly reliant on the groundwater. This is formally known as as groundwater dependent ecosystems.

The lesser known discharge is not all through visible springs like those on Chinaman's Beach. Much of the discharge from the coastal sands aquifers is actually concealed by the sea. It might be a surprise to many in some areas just off the coast there are zones with freshwater. The amount of water that can be discharged underground into the sea can exceed the discharge from terrestrial springs (e.g. Santos et al. 2009). These are the undersea equivalent of the Chinaman's beach springs. This is interesting from a aquatic ecology point of view because it may mean that there are ecosystems in the ocean that are dependent on freshwater! That is, groundwater dependent ecosystems in the sea.

Groundwater is an interesting feature of our region. It is a source of drinking water, irrigation water and even industrial water. It is often important as some ecosystems are dependent on it. It is also surprising since ecosystems can be dependent on fresh groundwater even when out to sea.

Postscript: about a month after this blog post a story emerged in the local newspaper about sinkholes or zones of quicksand on Chinamans Beach. These quicksand 'pits' look just like typical groundwater discharge areas. The Northern Star article can be found here.

*Santos, I.R, Burnett, W.C., Chanton, J., Dimova, N. & Patterson, R. (2009). Land or Ocean?: Assessing the driving forces of submarine  groundwater discharge at a coastal site in the Gulf of Mexico. Journal of Geophysical Research. vol114.

Tuesday 1 April 2014

Filling a gap with weathering textures

I've been a bit slack lately in posting. I usually have a post ready to go on the first day of every month with a few more over the month. But not so this time. It seems that life just hasn't given me the time to write over the last few weeks. So instead no post at all, here are a few pretty pictures of weathering patterns from the area.

Phyllite of the Neranleigh-Fernvale beds. In this case the darker part of the rock has been preferentially eroded by wind and wave action creating the early stages of a tessellated pavement. The quartz veins that are present stand proud from the surface. Technically this is not actually weathering per se... but oh well it looks pretty.
Weathering of the cross-bedding in this sample of Kangaroo Creek Sandstone develops a very pretty pattern.
Differential weathering in phyllite of the Neranleigh-Fernvale beds. The fabric of the rocks leads to some minerals being more susceptible to weathering by reactive sea water.