Federal US regulators came to the conclusion that the recent earthquakes in the us state of Texas, obviously, associated with the disposal of waste water during drilling in the oil and gas industry, which confirms the findings of scientists of the universities of the state, writes Reuters.
Officials of the Agency for environmental protection (EPA), the United States made a comment in a letter to the Commission on the Railways of Texas, which regulates the oil industry in the main oil-producing region of the country. The quakes were tied to the injection of salt water used in the drilling of wells during hydraulic fracturing. In the past, the Commission has questioned the results of University research.
“EPA believes that there is a significant likelihood that the seismic activity in North Texas is connected with the wells of industrial waste,” — said in a letter to the Agency. The EPA stated concern about seismic activity in the area of Dallas-Fort worth with regard to its possible impact on underground sources of drinking water.
On Tuesday, the Commission on the Railways announced a more stringent check new utilization of wells, participation in the technical hearings on seismicity caused by human activity, as well as support the installation of new stations for monitoring.
Previously, the regulator in the state of Oklahoma has banned tens of utilization wells, trying to reduce the number of earthquakes.
In recent years the question of the relationship between the application of the method of hydraulic fracturing and the occurrence of earthquakes has become particularly relevant: according to the U.S. geological survey (USGS) over the past six years, the number of earthquakes in the country has increased dramatically. So, if in 1973-2008 in the Central part of the country was on average 24 earthquakes per year with magnitude above 3 points, there 2009-2015 — already 318 per year, and in 2015 was was 1010 earthquakes.
The service expects the growth in the number of earthquakes in 2016 in several regions of the country where the actively producing hydrocarbons. Named the most seismically active States of Oklahoma, Kansas, Texas, Colorado, new Mexico and Arkansas. According to the geological service for the last five years in these States an increase was recorded of earthquakes and destruction, mostly man-made. Such earthquakes are caused by injection of fluids in drilling oil and gas wells, according to the Agency.
