The company has raised concerns about the potential for emissions and odours to force the dairy to shut down its operations at a cost of £11,000 an hour to avoid any risk of tainting its products.
It has also said that insufficient attention has been paid to the consequences for the dairy if the energy from waste site experiences plant failure, or unexpected or unplanned shutdowns.
Lynn Roberts, the senior site director, said: “Our site operates 24 hours a day, seven days per week, and utilises a process to skim whole milk leaving cream for butter production and simultaneously to dry the skimmed milk into powder.
“This means that having constant access to very large volumes of clean air for our dryer is critically important.
“If the air supply is compromised in any way Arla would simply have to suspend production,” Mr Roberts said.
He added: “Given the large volumes of food being produced at the site any suspension of production would have a major financial impact; we have estimated that every hour offline would cost £11,000.
“Moreover, given the size and scale of the Westbury dairy, if it cannot operate as normal the impact will be felt across Arla and across the entire dairy industry.
“Repeated suspensions of operations at the site would have severe implications in terms of added costs, and Westbury’s size and scale mean that if it is offline for any length of time the whole of the UK dairy industry could be affected.
“Arla has therefore concluded that the proposed incinerator is simply in the wrong place. That is why it has written to the council and other stakeholders objecting to the proposal being given planning permission.”
Arla Foods is a cooperative owned by nearly 10,000 Northern European dairy farmers, including around 2,300 in the UK.
The Arla dairy at Westbury was established in 2002 and is the country’s biggest manufacturing site for butter, employing around 250 people.
It receives raw milk direct from Arla’s farmer-owners and from other dairy companies and cream from sites owned by Arla and others.
Each year it produces 80,000 tonnes of butters and spreads and up to 55,000 tonnes of skimmed milk and buttermilk powders.
Its intake amounts to around five per cent of all of the milk produced in the UK.