A new set of proposed five-year air quality objectives running up to 2025 may have been pitched overly conservatively to make it easier for major future projects like a large-scale reclamation east of Lantau Island to meet them, according to a Hong Kong environmental advocacy group.
The objectives, revised every five years, set concentration limits for seven key pollutants and the number of times levels can be exceeded in a year, with reference to World Health Organisation (WHO) guidelines.
The Clean Air Network said the tweaks underestimated potential improvements from more than a dozen emission reduction measures proposed during the review period, leading to the setting of lax targets.
Senior community relations manager Loong Tsz-wai surmised that the unambitious targets were advanced to make it easier for future developments such as the government’s proposed “Lantau Tomorrow Vision” to pass their environmental impact assessment.
Announced by Chief Executive Carrie Lam Cheng Yuet-ngor as a cornerstone of her policy address last year, the plan involves creating 1,700 hectares of artificial islands for a new housing and economic hub in waters east of Lantau, in what would be the city’s biggest and most expensive infrastructure project.
According to the Environmental Protection Department’s air quality predictions for 2025, illustrated in a map, annual average nitrogen dioxide concentrations in the proposed reclamation area would be about 40 to 60 micrograms per cubic metre. This would fail to meet the 2025 objectives.
“In the end, they will probably just give them a waiver, which would allow the project proponent to follow the older, less stringent objectives,” Loong said.
A department spokesman said the Lantau plan would have to conduct and pass its environmental impact assessment study. The plan would have to comply with the air quality objectives (AQOs) “at the time of the decision”.
He cited the government’s Northeast New Territories development plan as another example of air policy being “manipulated” for the sake of development.
The development was exempted from having to meet the updated and tightened AQOs for 2015 in its environmental impact assessment. It instead followed the much looser 1987 standard.
“What is the point of the AQO then? Is it still a legally binding standard?” Loong added.
Pending approval from the legislature and environment advisers this year, the new set of air quality objectives for 2025 are expected to come into effect next year.
“This is a selective tightening … moving the goalposts,” Loong said. “They only choose to tighten what is already doing well so they know for sure the target will be met in 2025.”
Controversially, the review makes no proposed changes to other problem pollutants such as ozone and respirable suspended particulates (PM10), deeming any such tweaks to be unrealistic.
PM10 and ozone concentrations have increased significantly over the last three years and already fail to meet their current targets.
The number of times the PM2.5 limit can be breached in a year was drastically relaxed from 9 times to 35 times.
But Professor Steve Yim Hung-lam, an air pollution expert at Chinese University and member of the government’s Air Quality Objective Review Working Group, said this was justified.
“Annual averages are determined by long-term trends in emissions, but limits are exceeded easily during weather events like before typhoons, which are beyond anyone’s control,” he said.
According to the department, concentrations of PM2.5 and PM10, NO2 and SO2 in the city’s ambient air fell by 28 per cent to 54 per cent of the air quality objectives limit between 2013 and 2018. Concentrations of the same pollutants at roadsides have fallen to 36 per cent of the limits, a 32 per cent dip from five years ago, as a result of successful emissions control policies.