Prospector Mike Fitzpatrick, who has spent spare time at Ophir with a metal detector for decades, said his discovery this week was the tipping point.

He and others have been cleaning up rubbish at the goldfields for years and dutifully cleaning up mess they didn't create, but he said the sight of needles and used nappies earlier this week were the final straw.

"It's gone downhill badly," Mr Fitzgerald said.

"There are toys in the piles of rubbish and kids will see them and dive in and get pricked with needles."

He said it appeared someone had taken a trailer load intended for the tip and dumped it in Ophir, which was an escalation from the usual rubbish being left in the reserve.

The rubbish had been left in the scar in the earth left by miners during the gold rush, just up the hill from the campground at the Lewis Ponds Creek crossing.

He said the disrespect shown to the area, which was significant in early settlement history of Orange, was appalling.

"It's a historical area - they should have showed a lot more respect," he said.

"The other week I came through and someone had left nappies in the branch of a tree and not put them in the bin which was only a few metres away," Mr Fitzgerald said.

"I've seen families having lovely days out there and having a picnic and then they'll get up to go and leave all their rubbish lying around them."

He said often the rubbish looked like it was being left by people from out of town - "seems to be a lot of people coming up from Sydney and from out of town not taking their rubbish away with them" - but the recent load looked like someone from the region who should have gone to the tip.

"I mean fair dinkum."

A spokesperson for Cabonne Council said Ophir was managed and run by the Ophir Trust, "who are responsible for the care of the reserve generally".

"In this case, Cabonne Council's ranger has responded to a customer service request regarding rubbish being dumped in Ophir, however this is an isolated instance for Council's ranger," she said. The Ophir Trust Board couldn't be contacted for comment by deadline.