Casual workers, who are no longer being offered employment, allege more than 30 positions have been lost.

New chief executive officer Kristine Saywaker has declined to say how many casual staff have been affected.

She said casual staff were "not getting work any more''.

"We have plenty of permanent part-time staff to cover our roster and that is what we are doing,'' she told the Daily Liberal.

HSU lead organiser Jodie Cowdrey said the Dubbo RSL Aged Care Association wrote to the union on July 12 providing notification of major changes in the way staff would be employed.

"The letter said the aged care association board had authorised an organisational review of Orana Gardens with the primary focus being better outcomes for residents and the facility's overall operational model,'' Ms Cowdrey said.

"The letter advised the likely outcome of the review could result in a reduction of care service employees.

"HSU will not stand for the loss of any positions at the aged care facility. Aged care is an important area and the union would want to ensure HSU members are looked after.

"We would also be concerned about residents continuing to receive the proper care they deserve."

Ms Cowdrey said the July 12 letter indicated no professional nursing employees would be reduced.

She said the majority of nursing homes were staffed by care service employees "except for possibly one registered nurse (RN) per shift''.

"If care service employees are cut a lot of strain could be put on that one RN," she said.

Ms Saywaker said the organisational review at Orana Gardens was looking at three primary areas of quality improvement to meet "the changing needs of residents, the re-distribution of workloads for staff and the development of a sustainable operational model".

"The review will assist us to consolidate our care delivery model, improve our business practices and create an integrated platform of technology,'' Ms Saywaker said.

"Looking forward, the Dubbo RSL Aged Care Association will be focussing on growth opportunities thereby positioning the organisation into the future.''

Ms Saywaker said the review had been conducted "in constant consultation with staff" during the past few weeks.

"Nothing untoward is going on,'' she said. "I have not sacked a soul. We have followed industrial processes around managing the number of casual staff on the books. That is all we have done.''

Ms Cowdrey said the HSU would be paying "particular attention'' to Orana Gardens.

"We will be making contact with the Dubbo RSL Aged Care Association asking for full details of what is happening,'' she said.

"We will be requesting a reply within seven days.''

The Daily Liberal sought comment from Ms Saywaker and the Dubbo RSL Aged Care Association yesterday. A staff member at Orana Gardens said Ms Saywaker was not available. A Dubbo RSL Aged Care Association board member said a decision had been made to make no comment at this time.