Complex sentence: On 16 July 2012 research done by the Japanese government revealed the strong possibility that the S-1-fault beneath the power station might be active, raising doubts about the claim made by the company in 1997 that it is inactive.
Split into simpler sentences: On 16 July 2012 research done by the Japanese government did reveal the strong possibility that the S-1-fault beneath the power station might be active. Raising doubts about the claim made by the company in 1997, that it is inactive.