an upgrade the existing Nenagh Wastewater Treatment Plant from its current design…

Proposed development

an upgrade the existing Nenagh Wastewater Treatment Plant from its current design Population Equivalent (PE) of 12,000 to a PE plant of 22,000. The wastewater will be treated and discharged via an upgraded outfall pipe into the Nenagh River to the immediate east of the site. The proposed development will comprise of: Proposed construction of: • Dual inlet pumping station • Storm overflow chamber complete with overflow screens • 2 No. storm tanks including storm return pumps and tank cleaning systems • Preliminary Treatment Stream comprising: • Fine Screens complete with screenings handling systems • Grit Removal system complete with fat, oil and grease removal • Grit Handling system and fat, oil and grease storage tank • Sludge Process Stream comprising: • Sludge Import Station complete with ancillary equipment • Waste Activated Sludge Buffer Tank complete with ancillary equipment • Picket Fence Thickeners complete with ancillary equipment • Thickened Sludge Tanks complete with transfer pumps • Sludge Dewatering system complete with outdoor sludge skips • Polymer make-up and dosing plant • Return liquors pumping station • Sequencing Batch Reactor tanks and blowers with distribution chamber • Ferric sulphate dosing plant • Tertiary Treatment Disk Filter and wastewater pumping station • 2 No. Odour Control Units with additional passive odour units • New ESB MV substation complete with outdoor generator and bunded fuel storage tanks • New control panel kiosks • Upgrade of outfall headwall to Nenagh River • Site lighting • Flood defence walls to existing buildings and Flood Compensation Areas • Revised site entrance including layby area and palisade fencing • Flow measurement and sampling chambers Proposed repurposing of existing structures as follows: • Conversion of existing Picket Fence Thickener to a sludge import pumping station. • Conversion of existing Final Settlement Tank to a final effluent buffer tank. • Conversion of existing Final Settlement Tank to a surface water attenuation tank. • Diversion of existing Northern Catchment gravity main to proposed inlet pumping station. • Diversion of existing Southern Catchment rising main to proposed inlet pumping station. Demolition of the following: • Existing (northern and southern) oxidation ditches to be demolished and partially filled in. • Existing Return Activated Sludge lifting wheel arrangement • Existing Waste Activated System pumping station • Existing belt thicken

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A commencement notice has been lodged: works are under way or about to start.

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