A landfill contractor is being taken to court, accused of allowing pollution to leak into the city's waterways.
The leak at the Ta Kwu Ling landfill in the northeast New Territories was first reported by the contractor - Far East Landfill Technologies - last July. Controversy was sparked after the government withheld the information from the public for more than a month.
The wastewater eventually found its way into the Kong Yiu Channel, which flows downstream into the Shenzhen River, and then to Deep Bay, where the Mai Po nature reserve is located.
The first hearing is set for February 18 at Fanling Court, the Environmental Protection Department confirmed yesterday.
In a report to the Legislative Council environmental affairs panel, the department said: "We are pursuing the liability of the contractor … and enforcement action under the Water Pollution Control Ordinance."
Back in October, a report submitted to the department by the contractor said the leak was caused when a supposedly impermeable liner developed a hole.
It said the hole was caused by "material defects or movement of the side slope due to heavy rain" while wastewater was being channelled into a temporary storage lagoon.
The department reported yesterday that it had proposed improvements to prevent future incidents, including double impermeable liners for storing the wastewater and covers to prevent rainfall from raising levels of the polluted liquid.
Its report added that the contractor had also been urged to expand capacity of its ammonia-stripping plant, which removes ammonia from the wastewater, known as leachate.
Water-quality tests taken at the Kong Yiu Channel in December showed ammonia-nitrogen levels were still higher than allowed under the landfill contract.
Readings of ammonia-nitrogen - which can damage vegetation and soil - were 8.6, 6.7, 6.1 and 2.7 milligrams per litre over the first four weeks of December. The contractual requirement is 0.5 and the legal requirement is 5.