Nearby residents are claiming they have suffered harm from noise and odour of the factory at McDonald St, Numurkah.
The company has defended the action and argued they have addressed complaints about the factory operations.
Justice Stephen O'Meara reserved his judgement in June, after hearing weeks of evidence and said he expects a decision may not be handed down before November.
The plaintiff alleges that the emissions have caused a nuisance to lead plaintiff Kevin Green and group members, and that the defendant has breached a duty owed to them under the Environmental Protection Act 1970 to minimise the risks of harm to human health or the environment from pollution.
The plaintiff and group members claim damages for loss of amenity for disturbance to their sleep, comfort, health and wellbeing, and diminution in the value of their land as a result of the emissions, and seek an injunction to restrain the defendant from continuing the alleged nuisance.
The factory occupies about four hectares of land about half-a-kilometre from the centre of the town.
Oilseed crushing operations began at the GrainCorp factory in the 1970s, and GrainCorp acquired the business when the company purchased Gardner Smith Pty Ltd in 2012.
GrainCorp took over the management and day-to-day operations of the GrainCorp factory in October 2012 and has processed oilseed and manufactured oils at the GrainCorp factory since then.
Most of the site is located on land zoned Industrial 1 Zone.
The GrainCorp class action alleges that the lead plaintiff and group members experience a range of amenity loss and damage including diminution in property value, sleep disturbance, distress, inconvenience, annoyance and upset caused by the emissions from the GrainCorp factory which they receive at their properties.
The GrainCorp class action alleges that the emissions are unlawful constituting a common law nuisance.
The lead plaintiff in the GrainCorp class action is Kevin Green who, lives near the factory and has given evidence in the case.
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