Mulch contaminated with bonded asbestos has been found in the ACT, following findings of it at 40 sites, including schools, in NSW.

The suspect mulch has been on sale in the ACT since March and has been delivered to 27 locations in and around Canberra.

The initial source of the mulch is south-west Sydney business Greenlife Resource Recovery Facility and the dates for potentially affected mulch coming to the ACT are between March and November.

The ACT Environmental Protection Authority (ACT EPA) says the mulch, marketed locally as “cottage mulch”, was sold on to 24 companies and 27 addresses around Canberra.

The NSW EPA advised the ACT EPA on Saturday that potentially contaminated mulch was sold to ACT landscaping supply company Stonehenge Beltana in Pialligo.

Records are held for many of the purchases, so most customers have already been contacted and informed by the retailer. Others will be contacted in the coming days as they are identified.

The ACT has established a local taskforce, led by the ACT EPA and bringing together government expertise, including WorkSafe ACT, to take a risk-based regulatory approach.

Meanwhile, AAP reports from Sydney that more than 40 sites including schools, hospitals and parks have been contaminated with asbestos contained inside recycled mulch.

Domremy College at Five Dock in Sydney’s inner west became the fifth school to confirm asbestos following a number of sites being tested after asbestos was found in mulch at Liverpool West Public School earlier in February.

The college remains open on Monday with the contaminated site isolated and cordoned off.

Results are still to be confirmed at three southwest Sydney schools: Edmondson Park Public School, Mount Annan Christian College at Currans Hill and Trinity Catholic Primary School at Kemps Creek.

“We understand this may be unsettling for these school communities but these results are expected later today,” NSW Environment Protection Agency (EPA) said in a statement on Monday.

In western Sydney, St Luke’s Catholic College at Marsden Park has decided to close this week, while Penrith Christian School at Orchard Hills remains open with the contaminated site fenced off after asbestos discoveries at the two schools were confirmed on Sunday.

Liverpool West remains closed with students offered in-person learning at nearby Gulyangarri Public School, where Education Department secretary Murat Dizdar plans to visit on Monday.

An Aldi supermarket at Cobbitty, southwest of Sydne,y will reopen once a contaminated site there has been contained.

A site at Riverstone Sports Centre and an area of a shared path along the Parramatta Light Rail project at Telopea in Sydney’s northwest are also set to be contained on Monday.

Asbestos has been confirmed at three other sites which the EPA did not reveal for privacy reasons, saying they are not publicly accessible.

Fire and Rescue NSW crews inspected more than 120 sites identified by the agency on the weekend.

More than 90 per cent of the mulch identified as potentially containing asbestos had been tested, Premier Chris Minns told ABC Radio on Monday.

“We’re getting towards the end so I don’t want people to think this is never-ending,” he said.

The government is considering potential increases to fines.

“We’ll get the systems in place to make sure that if there’s penalties imposed it’s not just the cost of doing business for these big companies,” Mr Minns said.

Sydney Olympic Park has been cleared ahead of a big weekend of concerts in the entertainment precinct, including Taylor Swift’s shows.

The EPA is investigating a complicated supply chain as its probes how the mulch became contaminated.

EPA Chief Executive Tony Chappel said on Sunday the investigation would conclude with a full report to the public but cautioned against prematurely attributing blame.

The agency had been required to disclose a notice issued to Greenlife Resource Recovery preventing it supplying more mulch, which it is currently complying with, Mr Chappel said.

The company is challenging the prevention order in court.

Greenlife’s mulch is independently tested by approved laboratories and the company was confident it left its facility free of contamination, it said in a statement on Friday.