Stadt Moers Park Methane Stripping Plant Upgrade Works

Knowsley Metropolitan Borough Council (KMBC) manage a closed, unpermitted landfill site located at Stadt Moers Park, Pottery Lane, Whiston, L35 3RG ("the Site"). The Site received waste between 1945 and 1983, including fly ash and domestic refuse and has subsequently been restored into a Country Park with public access which is managed by KMBC under Part IIA of the Environmental Protection Act 1990.

As part of the management of the Site, leachate generated within the historic landfill is discharged to sewer in accordance with trade effluent discharge consent (TEDC) 693T02074HUY1 issued by United Utilities (UU) (Appendix A). Prior to discharge, the leachate is treated within an existing methane stripping plant (MSP) which was designed and built in 2005/6 and is located at the southern end of the Site, to the east of the M57 motorway and to the west of "Tushingham's Lake" at national grid reference SJ 46071 90331.

A number of operational issues have been experienced with the current treatment system and KMBC therefore wish to upgrade the system to one which will provide more efficient and reliable treatment with a lower demand for operation and maintenance activities than the current system.

Key objectives for the project include:

• the provision of reliable compliance with the conditions of TEDC 693T02074HUY1 presented within Appendix A throughout the intended design life of 25 years;
• the provision of reliable pumping of the leachate accumulating within the sump adjacent to the MSP compound to prevent the sump from overtopping throughout the intended design life of 25 years;
• minimising the H&S risks to operational personnel and members of the public associated with leachate management at the Site;
• minimising the visual, audible and odour related impacts of the leachate management system to preserve the amenity value of the park;
• minimising the ongoing operational costs of achieving compliance with TEDC 693T02074HUY1 and preventing the sump from overtopping