By 2017, five years into this conflict, a criminal trial was going on. Under scrutiny in the trial were the construction and use of Talvivaara's gypsum waste pond, for alleged scheduled and uncontrolled dumping of effluents into nature, as well as issues surrounding the handling and placement of the mine's various waste components. Prosecutors claimed that Talvivaara bosses committed their first environmental crimes as early as 2004 when the mine was in its planning and building stages. Prosecutors demanded suspended prison sentences of one year for Talvivaara Mining Company ex-CEO Pekka Perä, 10 months for ex-CEO Harri Natunen and eight months for an ex-division chief for aggravated environmental degradation. The accused denied the charges. By 22 March 2018 (reported for instance by Xinhua) a high court in Rovaniemi, northern Finland, sentenced Pekka Pera, founder and original director of Talvivaara mining company, to half a year in prison on probation on account of severe environmental pollution. Starting in 2015, the lawsuit was considered the most significant environmental criminal case in Finland. Two executives of the mining company were fined. A lower court had also fined Pera previously. The operation in Talvivaara nickel and zinc mine began in Sotkamo, Northern Finland in 2008. It used a water bio-diluting process in separating the ore. The waste reservoirs were problematic from the start. They overfilled due to rainwater, and contaminated water leaked to the environment. The wastewater included metal and gypsum. Major leaks occurred in 2008, 2010, 2012, and 2013.