Japanese research firms commissioned by the government have given a questionably low estimate for the maximum amount of lateral shaking from earthquakes that could affect the NPP planned for construction at Sinop by Atmea – a joint venture (JV) between Japan’s Mitsubishi Heavy Industries (MHI) and France’s Areva.

The Mainichi, citing “sources privy to the matter” reported on 7 January that the assumed "peak ground acceleration for the plant in the Black Sea province of Sinop has been estimated at a significantly lower level than that for Japanese NPPs in a possible attempt to reduce the construction costs.

The peak ground acceleration for the Sinop plant is estimated at around 400 gal, But experts said, given the topography and geography around Sinop, the estimate should be "at least 500 gal based on Japanese standards." For instance, the assumed ground acceleration is 620 gal for Kyushu Electric Power Co's Sendai NPP in southwestern Japan and 856 gal for Kansai Electric Power Co's Ohi NPP on the Sea of Japan coast.

The assessment was part of a study commissioned by the Agency for Natural Resources and Energy under the Ministry of Economy, Trade and Industry to examine potential NPP construction deals involving Japanese companies in Turkey and Vietnam. Tokyo-based Japan Atomic Power Co was contracted to undertake the JPY2.4bn ($20.52m) study, but outsourced the ground acceleration estimate and assessment of active fault zones around the planned construction site to other Japanese research firms.

Japan Atomic Power told Kyodo News it "cannot disclose details of the study." The agency said it has "not received a report" about the matter. The Atmea JV was granted the exclusive negotiating right for construction of the Sinop plant in 2013. The consortium plans to build four 1100MWe pressurised water reactors. MHI says a contract with the Turkish government is expected to be sealed in 2017 with operation of the first reactor starting in 2023.

According to Japanese researchers, some active faults are suspected around the Sinop plant site. In 1968, a quake of magnitude 6 occurred west of the site and some Turkish researchers warn of the possibility of a major earthquake occurring in the region. Local residents are protesting against the construction plan.