Government engineers have launched an enquiry after a former tunnelling foreman claimed that he was exposed to dangerous levels of radon while working on a section of Hong Kong’s controversial US$400m sewage tunnel network.
Drainage Services Department (DSD) senior engineer Raymond Tai Wai-man admitted that radon readings at two tunnels being built by Skanska International Civil Engineering had occasionally exceeded contract limits, set at 900 Becquerels per cu m.
He said the excess readings averaged 2000 Bq/cu m, although they amounted to less than 5% of all radon records kept since mid-1997 when Skanska began work on the tunnels. Deputy secretary for Planning, Environment and Lands, Kim Salkeld, has authorised the investigation following legal action by former tunnel worker, David John Baker.
Mr Tai said: "We will ask our consultants to step up the frequency of spot checking of radon levels in the tunnels to enforce the contract requirement. We will also inform the Labour Department about the allegation and request them to take follow-up action if necessary."
The investigation is the latest set- back for the scheme, which has been plagued by delays caused by cave-ins, equipment breakdowns, contractual wrangles and settlement problems.
Radon is a naturally occurring radioactive gas from rocks and soil which, if allowed to build up without proper ventilation can cause lung cancer.
