Environmental Impact Assessment
The partners commissioned the Geological Survey of Slovenia to produce a report on ‘the Potential Impacts on the Environment arising from Hydrocarbons Operations Using Hydraulic Stimulation in Deep Gas-Bearing Rocks in the Area of the Petišovci Field’ which concluded that:
- the exploitation of natural gas from Pg-10 and Pg-11A, using hydraulic stimulation, has not affected the environment to any significant level and will not do so provided it is carried out strictly in line with the ‘Safe Gas Extraction Procedures’ outlined here
- the environment will not be materially affected by the planned level of production of natural gas from Pg-10 and Pg-11A (below approx 500,000 m3/day), nor by the operation of the central gas station.
- The proposed gas production method is not expected to have any impact on potable or thermal waters due to the very thick sequences of sandstones and impermeable shales (approx 2,000 m) between the gas-bearing formations and the aquifers
- Emissions from flared gasses are not an issue as these are well within the prescribed limits. Emissions caused by damage to or failure of pipelines, well headings or the central gas station have not occurred because of good working practices. The risk of these happening in the future is negligible.
To summarise the Geological Survey of Slovenia’s findings:
The exploitation of unconventional gas using hydraulic stimulation in the Pg-10 and Pg-11A wells, the building of infrastructure etc and the treatment of gas in the central gas station are considered to be acceptable provided that ‘the six stages of Safe Gas Extraction ’ are adhered to, strict safety measure are applied, as defined in Slovenian legislation, and good practices are continued in order to avoid any negative impacts on the environment.
The contents and integrity of this report were commended by the Ministry of Agriculture and the Environment to Members of the Slovenian Parliament in a letter of 17 October 2012. At the same time, the Ministry drew the MPs’ attention to a report by the European Commission, which makes a distinction between the extraction of hydrocarbons from shale, widely used in the USA, and the extraction of hydrocarbons from sandstone, as in Petišovci. Negative publicity on the impact of hydraulic stimulation relates mainly to big stimulation operations in shale, rather than sandstone.
In the following month, November 2012, after much debate and as a display of confidence in the process, the European Parliament voted against a ban on hydraulic stimulation.