"We're using Wanganui firm WW Construction as well as local sub-contractors for the job. WW built our latest outlet in Bulls," he said.
The vacant property is about 100m from the London St intersection with Grey St on SH3 and directly across the road from the old St George's School site.
Mr Mills said the service station would include fuel pumps, an LPG filling station, car wash, and full shop facilities alongside the Wild Bean cafe.
"If people have been through Bulls lately they will have seen our new operation there.
"It will be just like that," he said.
"We haven't got a company-owned site in Wanganui and it presents a great opportunity for us."
BP will lease the land from owner Harvey Green, who had bought the former playing fields with a view to extending his already considerable BP service station business in the city.
But yesterday Mr Green told the Chronicle BP "was in a better position than I to be running a new service station in Wanganui, frankly".
"I probably wasn't able to front an operation quite as substantial as they could offer."
He said the fact that a BP Connect was to go on the site had meant a slight change to the resource consent he had initially applied for and been granted.
Mr Green's company, Petrosell Wanganui, owns and operates BP2go service stations on Taupo Quay, Victoria Ave and at the London St-Fitzherbert Ave junction in Springvale. He did own the Wanganui East service station but sold that 12 months ago.
Now he intends to consolidate his business interests at BP2go Taupo Quay, a site he owns. That means he will close the Avenue and Springvale stations. Petrosell owns the Springvale corner land and buildings but leases the Avenue site.
"They'll close the day the new BP Connect and Wild Bean Cafe opens," he said.
"Obviously, we've got more staff affected than we can accommodate on Taupo Quay, but BP will be offering any excess staff the opportunity of a position with them in the new London St service station and cafe."
Mr Green said his staff learned of the pending changes in the past few days and BP had also told them of the employment opportunities. About eight staff are employed at the Avenue and Springvale stations.
While his business interests will focus on the Taupo Quay site, Mr Green said they would be relocating the Undies laundromat operation from the Victoria Ave site down there as well, later in the year.
"We've got some new building going on there now, and that's where the laundromat and our offices will shift to."
He said no decision had been made on the future of the Springvale property at this stage.