UPDATED: Environment Bay of Plenty has successfully prosecuted one of New Zealand’s largest forestry management companies for polluting streams.

PF Olsen, a Rotorua company with branches nationwide, was fined $80,000 in the Tauranga District Court for two offices under the Resource Management Act (RMA).

The charges related to the collapse of several piles of logging debris in the Waiotahe forest near Opotiki in the eastern Bay of Plenty following three days of heavy rain in April 2008.

As a result of the collapse, large quantities of sediment and debris were released into nearby valleys and streams causing continuing effects to several waterways.

The fine awarded by the court is the largest for any prosecution undertaken by the Bay of Plenty regional council.

Judge Jeff Smith said the company was aware of its responsibilities under the RMA and its staff were working in an area that was extremely fragile.

PF Olsen spent $250,000 on remedial works following the collapse of its debris pile and has carried out a major review of its management processes when dealing with high-risk sites.

PF Olsen chief executive Peter Clark said the incident happened on some of the steepest and most erodible country in the world.

"While forests do a great job at minimising erosion during a 25–30 year growing phase, unfortunately the steep slopes are exposed during the harvesting phase until a new crop of trees gets established – usually a period of 5 or 6 years.

"In this case the slips occurred during a one in 20 year high intensity localised rainfall event.

"We recognise that the building of roads and skids required to carry out harvesting exacerbates the risk and that special skills and care are required to cope with such storms. Fortunately in this case no long-term environmental harm was done.”