The Animal Health Board is planning an aerial drop of 1080 over about 6500ha during the next two months to control possum numbers, which it says have increased "dramatically".
More than 90% of new tuberculosis infections are caused by vectors, mainly possums, which can transfer the disease to farmed cattle and deer.
Otago Tb committee chairman Phil Hunt said the bovine Tb programme had been very successful over the years, reducing Otago's infected herds from 300 to 17.
In the northern Blue Mountains possum numbers had increased to well over the acceptable threshold, to a point the disease could be transmitted.
It was hoped by also using deer repellent, which was not available in 2001, recreational interests would be protected, he said.
Using the repellent cost the Animal Health Board an extra $9 to $10 a hectare, plus cartage from the North Island.
Blue Mountain Hunter Liaison Group spokesman Stuart Murray said the 2001 drop was a "disaster" in what was a gazetted recreational hunting area.
Monitoring afterwards indicating the deer by-kill to be between 67% and 75%.
When possum numbers indicated further control work was needed on the block in 2005, the Animal Health Board suggested it would use deer repellent if hunters supported the operation, he said.
In 2006 the liaison group consulted widely among hunters and received "majority" support for the repellent trial, provided the deer by-kill was monitored by Landcare Research.
"We agreed to a one-off trial only. We do not want to endorse 1080 or any future use in the Blue Mountains or anywhere else," Mr Murray said.
While there was some research indicating the deer repellent was fairly effective on red deer, there was none on fallow deer.
A need to get the trial approved by Environmental Risk Management Authority (Erma) and the nationwide 1080 review delayed the operation by 12 months, he said.
The group now had to wait and see how effective the operation would be but hoped it would "dramatically reduce the deer by-kill".
Fallow deer numbers had increased in the area since 2001 but not to the levels before 2001, Mr Murray said.
"It had a quite significant, very serious impact on the population."
Landcare and the Department of Conservation would also carry out rodent and mustelid population studies following the operation.
