Worker's suit sparks tunnel radon probe

PUBLISHED : Monday, 19 July, 1999, 12:00am
UPDATED : Monday, 19 July, 1999, 12:00am

Chemical and radioactive exposure at two key tunnels in the troubled sewage disposal project are being investigated.

Government engineers will ask one of the project's three contractors, Skanska International Civil Engineering, to hand over any radon readings not released to government consultant Montgomery Watson, to check for safety.

Deputy Secretary for Planning, Environment and Lands Kim Salkeld authorised the investigation after a former tunnel worker filed a suit against Skanska in the District Court.

David John Baker, 43, is suing for compensation over injuries from alleged exposure to oil gas and other chemicals on September 30 last year at tunnel G at Tsing Yi while working as a foreman and probe driller for Skanska.

It is understood 'other chemicals' in the court application referred to carbon monoxide and radon radiation.

The sewage scheme consists of seven tunnels running across eastern Hong Kong Island, Tseung Kwan O, central Kowloon, Tsing Yi and Kwai Chung. Skanska is responsible for building tunnel F at Stonecutters Island and tunnel G at Tsing Yi.

'We have asked our consultants to investigate the allegation,' Drainage Services Department senior engineer Raymond Tai Wai-man said.

'In view of the allegation, we will ask the 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 up follow-up action if necessary.' Mr Tai admitted radon readings at the two Skanska tunnels given to the Government had occasionally exceeded contract limits, set at 900 Becquerels per cubic metre.

The excess readings averaged 2,000 Bq/m3, according to Mr Tai, and amounted to less than five per cent of all radon records kept since mid-1997 when Skanska began work on the tunnels.

Radon is a radioactive substance from rocks and soil that can cause lung cancer. Between 80 to 90 staff work at the Skanska site. A Skanska spokesman said he knew nothing about radon exposure complaints.

'[Mr Baker] was on sick leave prior to his termination of employment from inhalation of oil fumes, probably transmission oil. Radon - that's news to me,' he said.

Repeated delays to the harbour-tunnel project, originally scheduled for completion in mid-1997, have badly embarrassed the Government. It is now expected to finish in November next year.