To mark this year’s World Water Day, UNESCO and UN Water released the 2014 World Water Development report highlighting the key role that water and energy play in economic development. According to the report, some 768 million people do not have access to an improved source of water, while 2.5 billion people do not have access to adequate sanitation. To assume, however, that people living in developed countries are somehow exempt from legitimate concerns about the safety and quality of their water belies today’s reality.
Take the concerns about the potential effects on water quality in the US from a well completion technique known as hydraulic fracturing, or ‘fracking’. The above report identifies water as a critical input for hydraulic fracturing and cites typical water injection volumes at 8 to 30 million liters per well. Admittedly, this is a very wide range and of little help to understand the environmental impact without knowing the underlying assumptions. In the US, two historic laws regulate the safety of water supplies: the Clean Water Act (CWA, 1972) and the Safe Drinking Water Act (SDWA, 1974). The SDWA, which is administered by the Environmental Protection Agency (EPA), allows for the protection of water quality by regulating the subsurface emplacement of fluid by well injection. It is noteworthy that the Energy Policy Act of 2005 added language to exclude “the underground injection of fluids or propping agents (other than diesel fuels) pursuant to hydraulic fracturing operations related to oil, gas, or geothermal production activities” – meaning that any chemicals mixed with water and injected into shale formations in this process are beyond the regulatory scope of the law. The typical composition of fracking fluids is 98% sand and water along with 2% chemicals – such as “acids, surfactants, biocides and scaling inhibitors” – all added to increase well productivity. Here the UN-Water report makes the following points:
“As producers become more water efficient, using less water per well, the relative proportion of chemicals increases. A significant fraction of the injected fluid comes back out of the wells as wastewater (including drilling muds, flowback water and produced water). The volume of produced water that is returned varies greatly, depending on the geological characteristics of the formation; it can be as low as 15 per cent and as high as 300 per cent of the injected volume. (…) Oil and gas extraction yields high volumes of ‘produced water’, which is water that comes out of the well along with the oil and gas. Produced water usually has very high salinity and is difficult to treat. (…) In many cases, the volume of produced water far exceeds the volume of fuel produced.”
In general, all types of wastewater are governed by the Clean Water Act (CWA), which regulates pollutants and protects any type of surface waters such as lakes and rivers. Counterintuitively however, wastewater from ‘fracked’ wells is exempt from federal requirements for handling hazardous waste. In addition, the EPA cannot regulate the drilling process itself due to restrictive language of the SDWA. Consequently, both laws do not reflect today’s realities and require congressional overhaul and/or amendments to allow for further safe expansion of the shale gas revolution without potentially compromising vital water supplies. Up-to-date regulation has to march in lockstep with the expansion of the shale revolution. It is high time – borrowing words from Russell Gold in his new book “The Boom – How Fracking Ignited the American Energy Revolution and Changed the World” – to end the unofficial policy of drilling first and asking questions later.
Read a 3-part Breaking Energy series covering various wastewater recycling technologies currently employed by the oil & gas industry to address this issue here.
The graphic below shows several potential sources of water-related pollution not adequately addressed by current pre-shale revolution laws:
- Risk of leakage from wells into the water table
- Risk of leakage from fracking fluid or from ‘produced water’ into the water table
- Risk of leakage from improperly treated ‘produced water’ and fracking fluids from flowback into the soil and water table
- Risk of infiltration of fracking fluid into water table; risk of migration of naturally occurring toxic substances