REUTERS Ukraine on April 5 started the season of pumping natural gas into its underground storage facilities (USFs). Read alsoUkrainian gas stocks shrink 49% to almost 7.8 bcm since Nov 7 The daily volume of gas injection into the USFs was estimated at 12 million cubic meters (mcm) as of April 5. At the same time, 3.4 mcm of gas was withdrawn from the storage facilities, according to the state-run gas transport system operator Ukrtransgaz. As of April 6, 2019, gas reserves in the country&#39;s USFs were estimated at 8.76 bcm, while the USFs were filled by 28%, it said. As UNIAN reported earlier, on November 7, 2018, Ukraine stopped injecting gas into the underground storage facilities and began pumping it out to ensure the smooth heating season. By the start of the 2018-2019 heating season, Ukraine had accumulated 17.2 bcm of gas in its underground storage facilities, which was a record high natural gas stock over the past six years. UNIAN memo. Ukrtransgaz operates 12 underground gas storages (USFs) with a total storage capacity of about 31 bcm. The USFs are an integral part of Ukraine&#39;s gas supply system and gas transit through its territory. The company is also the operator of trunk gas pipelines carrying gas from Russia to the EU. Ukrtransgaz is wholly owned by NJSC Naftogaz of Ukraine.