The firm, formerly known as the State Fuel Office, is suspected of negligence in its harvesting of dozens of peat bogs. The case goes to trial at Southern Ostrobothnia District Court in Seinäjoki in late January.
Vapo faces charges of neglecting its responsibilities regarding emissions monitoring during the peat collection process over a period of years.
The South Ostrobothnia Centre for Economic Development, Transport and the Environment filed an investigation request with police over the issue.
Some of the wetlands are located in the watershed areas of the Lapuanjoki and Kyrönjoki rivers in western Finland.
Yle has learned that Vapo is suspected of failing to order emissions testing between 2008 and 2010.
Renewable biofuel?
Digging up ancient peat bogs for use as fuel has come under increasing criticism from environmental groups in recent years. The government lists peat biofuel as a renewable energy source in its calculations of how Finland will meet the EU’s target of 20 percent renewable energy by 2020.
However some biologists argue that peat bogs, which take thousands of years to recover from harvesting, should not be considered a renewable resource. The process also affects water quality and wildlife habitats.
Peat now accounts for six or seven percent of Finland's energy consumption. About one third of its land area is made up of various types of bogs and wetlands -- which gave the country its Finnish name, Suomi.