Until recently, we believed that our actions to properly deal with odour, mainly by following expert advice, being the application of a thick layer of mulch across the landfill southern batter (to act as a Bio Filter) as well as the installation of a landfill gas extraction system, incorporating a flare, fixed the odour problem, and we spared no expense nor time to implement them. The EPA will corroborate this. Those solutions fixed the problem, for a time.
What has since occurred is that the thick layer of mulch is composting after the recent heavy rains, breaking it down, and it then starts to smoulder which has caused the recent odours. Once this occurred, we started receiving odour complaints and almost all commented that the odour had “changed”. We first checked the flare and extraction system, but it was working perfectly. Upon further investigation we found that the application of the mulch was the issue, for 2 reasons. The first being that the composting was occurring, creating smouldering hotspots and adding water only served to temporarily extinguish it but encourage more composting after a couple of days. Second, the mulch also hides any cracks that open up in the capping due to the wet and dry cracking that normally occurs in any clays used and were the mulch not there, we could identify these cracks and repair them immediately as part of normal operations. But because of the mulch, we can’t see the cracks.
As a result, we have decided to remove the mulch covering on the batter as, whilst applying it seemed like good advice, it has proven not to be so. We are removing it as we speak and these works are expected to be completed by weeks’ end, weather permitting. In the meantime, we will only allow local waste to be accepted to allow us to focus on our batter works, without interrupting our service for our local-area customers.
Whilst on that topic, I note a comment from a long-term critic of both the Bowral brick operation and now us: it has been suggested that we are/have been taking incorrect waste types. This is not correct, since Nov 2019 (when we assumed the business from the previous owners) we have only been taking predominately local wastes and only types as approved by EPA, being demolition and construction wastes and small amounts of local Asbestos, as requested by Council. Anyone who has used our facility knows this, as we reject any load that has food or is odorous, and we don’t bury (but export to a composting facility) any green waste that we find when we sort all incoming, non-pre-sorted loads.
We expect that as soon as we finish our work (hopefully by weeks’ end) the odours will again be well controlled by our gas extraction system, as before. We sincerely apologise for our well-meaning but unsuccessful trial of biofilter mulch which, frankly, brought back odour which was otherwise eliminated. We are fixing that.
Bowral Waste Centre