They call themselves the Thursday Gang.
Four retirees who, almost every Thursday morning, head up to Te Puna Quarry Park to do the work that someone has to do.
It can be dirty - but they don't mind. Nelson Whittaker, Tom Coomber, Ray Hockley and the eldest, at 96, Alf Rendell are happy to put their skills and experience to good use.
Ray says Alf is an inspiration.
"That boy really pulls his weight," he says.
"If there is any painting to be done, Alf is right into it."
"He's not a plant man, but he is a first-class weeder," says Te Puna Quarry Park committee member Jo Dawkins.
Alf is a distant relative of secretary Dulcie Artus.
"We used to talk about [the quarry] quite a bit and when my wife died, I had some spare time so I started coming up," says Alf.
He says his weekly visits to the quarry are as much about fellowship as anything else.
He has had one or two mishaps in the 12 years he has been going to the quarry.
"Nothing serious - but plenty of times I've taken the odd bit of skin off - and I fell once and rolled down the hill."
He has also discovered that a ponga does not make a very good rain shelter.
"But I am proud of the fact that I have had a hand in it, and am part of it."
Nelson has been a volunteer since he retired as a maths teacher at Mount Maunganui College.
"As soon as I stopped teaching I came out here and I also work in the depot and garden at Waipuna Hospice."
He had visited the quarry and was interested in the work being done. He has a farming background and says volunteering "beats sitting around the house".
Ray is a retired builder and has proved to be a real acquisition, says Jo.
He was instrumental in getting a new butterfly house built, as well as a new bridge over the stream near the water wheel, but is modest about his contribution.
"I just show them how to do it properly," he says with a grin.
He says when he retired as a builder after the last financial crisis, he was looking for somewhere to volunteer his skills.
"I'd been up here [to the quarry] and thought I'd have a go at this. I wanted somewhere where I was able to do building-type work - I"m not overly keen on pulling out weeds."
While the Thursday Gang, unsurprisingly, give their time on a Thursday, Jo says the main day for volunteers is a Tuesday when there are regularly large numbers present.
"[The quarry] wouldn't be here if it wasn't for the volunteers - and they are from all walks of life. We get all ages, but generally they are getting older, so we could do with more young ones."
Anyone interested in finding out about volunteering can call Jo on 552-5789.