Presence of Karoo shale gas 'uncertain'

Visual simulations of a wellpad located in the Central Karoo landscape. During the day (top) and at night (middle) indicating visibility at a range of distances from 500 m to 5 km, before mitigation. The flatness and low vegetation in the Central Karoo enhances visibility. Night time visibility of lights would tend to be pronounced in the dark rural landscape of the Karoo. A visual simulation of a wellpad in a Karoo landscape at a distance of about 300 m (bottom). The adjacent farmhouse gives an indication of the scale of the drilling rig. pic Assessment report

Visual simulations of a wellpad located in the Central Karoo landscape. During the day (top) and at night (middle) indicating visibility at a range of distances from 500 m to 5 km, before mitigation. The flatness and low vegetation in the Central Karoo enhances visibility. Night time visibility of lights would tend to be pronounced in the dark rural landscape of the Karoo. A visual simulation of a wellpad in a Karoo landscape at a distance of about 300 m (bottom). The adjacent farmhouse gives an indication of the scale of the drilling rig. pic Assessment report

Published Nov 21, 2016

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THE Strategic Environmental Assessment (Sea) report, assessing the possible impact of fracking, says there may be no economically extractable gas in the Karoo.

The report, released by the CSIR, the South African National Biodiversity Institute (Sanbi) and the Council for Geoscience this month, says that while the Karoo Basin is known to contain natural gas, geological upheavals hundreds of millions of years ago – specifically the intrusion of hot lava and the pushing up of the Cape Fold Mountains – are believed to have reduced the volume of gas originally in place, and the total quantity of shale gas that occurs within the area is uncertain.

“Indications are that remaining gas is most likely concentrated in the area between the Cape Fold Mountains to the south, and the doleritic Nuweveld Mountains to the north, and at depths greater than 2km below the surface,” the report says.

Gas is versatile in the national energy mix as it has a range of direct and indirect end uses.

In addition to generating electrical power, natural gas could be used for transportation, as feedstock to produce liquid transportation fuels for fertiliser production, for industrial heat processes, for space heating and for residential cooking and water heating, if appropriately priced and secure in supply, the report says.

But without mitigation, the risk to shale gas workers of exposure to air pollutants is high, as is the risk to the climate from unintended methane leaks.

Under the "Big and Small Gas Scenarios", the risks of exposure to waste streams is high.

The report says the cumulative and unforeseen impacts of shale gas development (SGD) on biodiversity, as well as effectiveness of mitigation, must be monitored.

SGD could also deliver significant economic opportunities, with the potential to create 2 575 direct operational jobs in drilling, trucking and power generation.

Residents of the study area will probably be able to fill 15 to 35 percent of these positions initially, with the number increasing over time as training proceeds.

“The decision regarding SGD is not a binary ‘yes’ or ‘no’ question.

"There are a number of decisions which are made through multiple decision-making 
processes spanning all spheres of government and civil 
society.

"If South Africa does choose to proceed with exploration, and an economically and technically suitable reserve is discovered in the future, due assessment of regional and cumulative impacts should inform decision-making prior to commencing with production of gas in the Central Karoo at a significant scale,” the study says.

Treasure Karoo Action Group chief executive Jonathan Deal said: “Coming on the heels of the Assaf (Academy of Science of South Africa) report, the Sea is 
in our view a further vindication of the concerns raised since 2011.

The tone of the findings is cautious and very 
honest about unknown risk accumulation and the unpreparedness of South Africa in 
technical, legislative, monitoring and infrastructure 
terms to manage an 
activity such as shale gas development.

"The findings, in many instances, dovetail with those of the ASSAF scientists,” said Deal.

The departments of Environmental Affairs and Energy did not respond to queries by deadline.

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