Sniffing out Te Maunga's pong

By Graham Skellern
Just who is the culprit for the foul smell that regularly wafts through the Te Maunga area - the refuse transfer station, the wastewater treatment plant or the composting centre?
This is the question exercising the minds of an Environment Bay of Plenty hearings panel considering a resource consent application by Perry Environmental to double the size of its composting operation on land at Te Maunga designated for waste management.
Nearly 40 residents living nearby are objecting to the application, claiming the Tauranga Organic centre operated by Perry will produce more offensive odours.
They say the odours already enter their houses and linger in the soft furnishings, and affect their health and well being. But evidence presented to the hearing at Mount Maunganui on Monday indicated that the composting centre might not be the one to blame.
An independent analysis commissioned by Environment BOP concluded that the periodic odour problem was caused by one or more of the five possible sources.
The most likely sources were the handling of chicken manure at the composting centre, the smelly refuse arriving at the refuse station and peak or excessive loading through the wastewater treatment plant.
The analysis confirmed the composting facility was the source of odour on seven occasions; however, the source of 67 per cent of all complaints could not be identified.
Karen Parcell, an environmental consents officer for Environment BOP, said in her report that pinpointing the actual source of the odour had proven difficult.
The descriptions of the odour were vague - words such as "putrid" and "stench" were used - which gave no insight in to what the actual source might be.
She said the best description of the odour was "dog droppings" - a smell that could possibly be associated with the nearby sewage plant.
Joan Forret, Perry's lawyer, said in the last year there had been a significant increase in the number of complaints alleging that an offensive odour came from the Tauranga Organic Centre - not one of those complaints had been established conclusively.
She said Perry believed most complaints related to the wastewater treatment plant.
"Those odours are not dissimilar to the odours associated with composting of bio-solids. That is perhaps why some longstanding neighbours have connected the odours with the applicant's site."
Perry general manager Michael Lord said the most odorous materials at its Te Maunga site were chicken manure and a compost product designed specially for kiwifruit growers.
He said his company would permanently cover the chicken manure pile to minimise the effect of odour and it would add more carbon to the compost product.
"We are also pricing a new compost turner, valued at $400,000, that would allow us to turn the rows 10 times faster and also spray water vapour on to the compost to contain water soluble molecules and odour disturbed during turning.
This would decrease odour, said Mr Lord.
The hearing was told that the Tauranga Organic Centre composts about 12,000 tonnes of greenwaste and 3000 tonnes tonnes of chicken manure a year, selling mainly to the kiwifruit, avocado and maize growers.
Over the last 12 months, the composting material was spread over 1300ha, producing 26,000 tonnes of kiwifruit.
Mr Lord said composting was a marginal commercial business economically and a second composting pad would allow Perry to manage the operations more effectively.
Environment BOP planners are backing the consent application, although they have recommended it should last for just five years.
The arguments from the objectors will be presented to the hearings committee of Robin Ford, Athole Herbert and Ian Noble on Friday.