Other utilities are provided by private entities or South Korean government-owned companies. Seorabeol City Gas, an affiliate of GS Group, provides gas to the Gyeongju residents, while, electrical power is supplied by the public enterprises, Korea Hydro & Nuclear Power via the Wolseong Nuclear Power Plant. The plant is known for the only nuclear power plant operating PHWRs (Pressurized Heavy Water Reactor) in South Korea and supplies about 5% of South Korea's electricity. The owner, Korea Hydro & Nuclear Power began to build the Wolseong 1 in the districts of Yangnam-myeon, Yangbuk-myeon and Gampo-eup in 1976. Since 1983, the power plant has been providing commercial service and operating with the PHWRs that has a capacity of 678,000 kW. As the construction of each Wolseong 2, 3 and 4 with a capacity of 70,000 kW were completed respectively in 1997, 1998 and 1999, Wolseong Nuclear Power plant site has been successfully operating the four PHWRs plants. New project, Sinwolseong No. 1 and No. 2 are currently under construction which is estimated to be completed until 2011–12. The Wolseong Low and Intermediate Level Radioactive Waste Disposal Center, which treats and stores low and intermediate level radioactive waste from the local power plants, is overseen and inspected by the Korea Institute of Nuclear Safety (KINS).