Giant ‘sinkhole’ spewing out ‘alien’ brown foam appears on sports pitch near HS2 site

A giant ‘sinkhole’ spewing out “alien” brown foam has appeared on a rugby pitch near where HS2 is being built.

Work on the high-speed rail project was stopped for several hours after the unusual foam was found bubbling out of the ground by dog walkers at Ruislip RFC in west London.

According to HS2, workers moved to seal off the area which was “most likely caused” by one of the tunnelling machines passing through a small pre-existing borehole.

Jatin Radia, 45, chairman of Ruislip RFC, described the bubbling pool as “alien” and said he “couldn’t believe it” after seeing photos of it on the field.

He said: “I was watching my 14-year-old son play NFL on Saturday morning when my phone started blowing up. Members of the rugby club were sending me photos and videos asking me what was going on.

“It looked alien and unnatural. It reminded me of a volcano spewing up lava. I couldn’t believe it was anywhere in the UK.”

Mr Radia quickly alerted the police about the “foaming sludge”, as well as the environment agency, Hillingdon Council and HS2 to find out what was happening.

As part of the construction process for the controversial rail line, HS2 engineers are boring a tunnel under Ruislip Station which is adjacent to the rugby club.

Mr Radia said he arrived at the rugby ground at around 1pm and was met by two HS2 investigators. He explained: “We were walking around having a look when my 14-year-old son picked up a stick and threw it in. He turned to me and asked, ‘We’ve watched the Marvel movies and Doctor Who, if we jump in, will it take us to another dimension?’

“We understood very quickly from the HS2 guys that it wasn’t sewage because it didn’t smell, but there was no way we were going to touch it. It was foaming sludge, and the fear was whether it was toxic.

“I left my number with the guys from HS2 and asked them to get in touch once they knew what was causing it. They quickly cordoned off the area and put up danger signs.

“The real concern was is it toxic, is it harmful, and if it’s happening at the edge of our rugby ground, what’s happening underneath the houses where they’re tunnelling?”

Mr Radia also expressed concern for the rugby club, which has 600 members, and said it is his responsibility as chairman to ensure the pitches are safe.

He added: “My concern was, what else could happen? We quickly put out a note to our members saying this is going on, we don’t know what it is, don’t go near it. It’s a community sports club and we volunteer because we love rugby. As chairman, it’s my responsibility to make sure the pitches are safe.

“We run training sessions every evening and play every weekend - there are always matches going on. In two weeks’ time, we are hosting a festival for Middlesex County, and we’ll have 450 nine and 10-year-olds running around.

“My fear is, could kids be harmed if it happens on the pitch while they’re playing? My message to HS2 is, ‘Please investigate, give us a thorough report on why it happened and give us comfort that it continues to be safe for our rugby club to operate.’

“As a local resident, it’s only natural that we have concerns that HS2 is done properly and professionally.”

The area where the ‘sinkhole’ appeared remain cordoned off and Mr Radia said the foam has now dissipated. He has also received a letter from HS2 informing him that the pitches are perfectly safe to play on, he said.

An HS2 spokesperson said the pool appears to have come from a pre-existing borehole and the leak has now been sealed. They said in a statement: “Upon discovering the small pool of foam in Ruislip on Saturday, HS2’s main works’ contractor SCS (Skanska Costain STRABAG) sealed off the area to investigate.

“The pool appears to have come out of a pre-existing borehole, causing foam to travel up and pool on the surface. The area is safe, the leak has been sealed, and the foam has been cleared. There has been no impact on the programme schedule.”