Bulgaria considers shale ban - UPI.com SOFIA, Bulgaria, Jan. 18 (UPI) -- U.S. energy company Chevron could get the nod to examine shale gas deposits in Bulgaria only if there are guarantees regarding safety, the government said. Bulgarian lawmakers debated a measure Wednesday that calls for a nationwide ban on hydraulic fracturing, a process used to draw natural resources out of underground shale deposits. Critics of hydraulic fracturing note some chemicals used in hydraulic fracturing fluid could reach groundwater. A series of small earthquakes in the United Kingdom and United States have been attributed to shale natural gas development. Last year, Chevron landed a preliminary deal to explore for shale in Bulgaria after a government official said there was enough shale gas to meet domestic demand long into the foreseeable future. Bulgarian Prime Minister Boiko Borisov had said Chevron could continue so long as there were worldwide guarantees that hydraulic fracturing was safe, the Sofia News Agency reports. U.S. Ambassador to Bulgaria James Warlick said Chevron has millions of dollars in investments planned for Bulgaria and a long safety record to support its shale ambitions in the country. Thousands of activists took to the streets in Sofia last weekend to protest shale gas development in the country.