Tamworth BMX Track has been closed to the public after asbestos was discovered on the site.
Council owns the site used by Tamworth City BMX Club which includes an extensive dirt track and a number of buildings including the clubhouse.
Tamworth Regional Council's manager of sport and recreation Paul Kelly said work started on installing the fencing on Wednesday afternoon.
"We had staff from a specialist firm at the BMX track on Tuesday for a regular inspection of buildings and some suspect material was seen on the dirt track," he said.
"Four samples were collected for testing and late yesterday we were advised the testing confirmed the material contained Chrysotile and Amosite asbestos in a non-friable broken bonded material (fibrous cement sheeting or similar).
"We immediately contacted the BMX club and started to fence off the site as a matter of public safety."
Mr Kelly said further testing will be carried out on-site to determine the extent of the contamination.
He added that it is suspected that the BMX track includes soil which was filled with asbestos-containing material.
Council will have the specialists conduct extensive testing on-site starting Friday.
Mr Kelly said It is hoped the test results will be known by Friday next week to allow an action plan for remediation of the track to be formed.
Council will be working with the NSW Environment Protection Authority to manage and remediate the site.
"The safety of club members and the wider community is our immediate concern," Mr Kelly said.
"We are acting based on best practice advice that closure of the site is the right action to take pending the outcome of further testing."
Emma Cooper, secretary of Tamworth BMX Club, said they are still planning for the BMX NSW State Series in May but they have no way of knowing if it will go ahead.
"It's affecting the grassroots club greatly," he said.
"We have no training facilities at all now. That impacts all our rides, but primarily our elite riders who are at the beginning of a competitive season."
Some riders are set to head for a national competition in a few weeks and the closest club is three hours away.
Ms Cooper said all the members have been informed by email that the club has been closed indefinitely.
She added the riders, and the volunteers, are extremely disappointed.
From three members two years ago, the club now has 44 members, and Ms Kelly said something like this can see a decline in numbers.