SMOKE - ITS A BURNING ISSUE
Outdoor Burning Trials - measuring the  effectiveness of Best Practice burning methods

Each Autumn and winter, entire blocks of apple trees are burnt as part of orchard replacement programmes throughout the Tasman district. These trees and root balls are often diseased with European canker which for biosecurity purposes necessitates the immediate disposal of the tree once it is removed from the soil. Burning of this 'wet green' wood produces excessive  amounts of smoke.
 

From May to September, temperature inversion layers form on cool and calm days which puts a 'ceiling' on how high smoke can rise and disperse. Under ideal weather conditions smoke can be held close to the ground under this layer for days at a time. Over this winter period, Tasman District Council receives large numbers of complaints from residents regarding outdoor burning practices, smoke nuisance and air quality.
 

This presentation will detail an outdoor burn trial which TDC undertook in conjunction with SCION to compare 3 methods of burning:  a basic permitted activity burn; a current best practice burn; and a trench and fan burn method which is being implemented locally by an agricultural contractor. SCION measured all parameters around the burns and discharges from the fires.
 

TDC's aim was to provide scientific evidence to support implementation of better burning practices and demonstrate that a basic permitted activity burn  is not good enough in today's environment; that current best practice can be improved on  - and that we can burn wood including green waste with very little smoke or particulate discharge.
 

The presentation will focus on the trial methodology, results and how TDC intends to use this research to help improve burning practices in the Tasman district, this is also of relevance to a number of other regional councils.