TASMANIAN timber company Gunns has sought changes to its pulp mill permit from Tasmania's Environment Protection Authority.
Authority director Alex Schaap said yesterday that Gunns had asked for the permit to be varied because of changes to its operations since it was issued.
"They have been sought as a consequence of (Gunns) moving directly to plantation feedstock and the adoption of an elemental chlorine-free light process," Mr Schaap said.
"The request from Gunns is seeking an increase in the pulp production limit from 1.1 to 1.3 million tonnes per year.
"Gunns argues that this will not require any increase in the woodchip production limit."
The company's request also proposes a reduction in the production and emission of some chlorine compounds and reduced emission of sulphur compounds.
Gunns wants approval to produce hydrogen peroxide and proposes alternative means of defining the marine mixing zone and accounting for the emission of nitrogen oxides.
Mr Schaap said that it was normal practice for the authority to receive permit variation requests.
The Environmental Management and Pollution Act 1994 gives the EPA director authorisation to do that by issuing an environment protection notice.
"Such variations to permits are a routine part of business for the director as permits often require amendment to keep up with changing circumstances," Mr Schaap said.
Such routine procedures were not generally made public.
"But I recognise the heightened interest in this case, and that is why I am advising the public that it has been made," he said.
He hoped to finalise the matter within 10 weeks.