SuDs Management at Glenconway Windfarm SuDS Introduction to Gael - PowerPoint PPT Presentation

SuDs Management at Glenconway Windfarm SuDS

Introduction to Gael Force Renewables SuDs

• Gael Force Renewables Ltd was formed in 2011 by McLaughlin & Harvey Ltd and William & Henry Alexander (Civil Engineering) Ltd to target onshore Wind Farm opportunities in GB & ROI. SuDs

Gael Force Renewables – What We Do : • 150 years of Civil Engineering Experience • Gael Force offer full Design and Build Services • Early client and designer involvement so that innovative, safe, buildable solutions are developed. • At Gael Force we implement lessons learnt to ensure our teams constantly progress, develop and refine skills, methodologies and work sequences • Full time on site Environmental Professionals SuDs

Project - Balmurrie Fell Wind Farm, Stranraer, South West Scotland. (7 x 1.3 MW Siemens WTG) SuDs

Project – Glenconway Windfarm, Limavady, Northern Ireland (20 x 2.3MW WTG) SuDs

Design to Construction SuDS

Settlement Ponds SuDS

Silt Fencing SuDS

Clean water cut off drains SuDS

Swales & check dams SuDS

Breakouts SuDS

Settlement Areas SuDS

Monitoring Effectiveness • Water Quality testing (internal & external) • External inspections by Designers • Internal weekly inspections by Environmental Representative • SEARS (Safety Environmental Awareness Reporting Scheme). Positive and Negative issues raised by everyone on site. SuDS

SuDS

Water Quality Testing • External water quality testing was carried out every two weeks at 5 locations for Phase 1 and 8 locations for Phase 1 & 2 • Testing covered 21 chemical parameters and biological (macro invertebrate) monitoring • Internal samples took place daily for phase 1 and weekly for phase 2. Parameters included turbidity, dissolved oxygen, pH, temp & EC. SuDS

Environmental Awareness • Water Quality results are displayed on site • Correlation between turbidity and rainfall is also presented on graphs. SuDS

Toolbox Talks • Every Tuesday morning • Covers key issues such as waste, energy, water pollution • All site staff shared the responsibility SuDS

Environmental Awareness SuDS

Environmental Coaching Environmental Sessions to date:- SuDS (McCloys) Peat Stability / Peat Slides (BLP) Archaeology (Gahan & Long) Flora and Fauna (Blackstaff) SuDS

SuDS

Conclusion • SuDS design must account for inclement weather conditions • SuDS design must be site specific • SuDS features must be installed prior to works starting • Very beneficial to have an on site environmental representative • Water Quality monitoring is important during construction – even visual inspection of water courses • Maintenance of SuDs Features is critical SuDS

Construction-Phase Temporary SuDS: A75 Case Study Richard Collins BSc MSc AIEMA

Construction Context 3.67km carriageway realignment and upgrade: • include earthworks, drainage and culverts, utility works, surfacing & underpass construction Existing drainage mitigation inadequate • Filter drains & 4 balancing ponds with reed beds • Key Environmental Aim ‘Protecting the Pow Water tributaries during construction’

Challenges & Uncertainties Geology & soils •  Earthworks intensive  EIA stated ‘potentially increased sedimentation’  True nature of soils

Fine Clays

Spatial constraints •  Limited opportunity for temporary SuDS locations

Temporal Constraints •  Not scheduled in programme of works  Resources to complete with immediate effect  Costs

Usual Suspects Exposed soils: ensuring capping/seeding is  completed ASAP Stockpiles: limiting, stabilising  Washing & washout facilities  Haul roads: wheel wash operative (spatial  constraints) Dewatering: sumps, releasing at suitable times  Inclement weather: be prepared 

Water Management Strategy Liaise with local SEPA representative  Alum sulphate required: minimal dosing policy  Tiered, impermeable treatment zones  Maintenance plan: Daily checks  pH (6-8) & turbidity (<10ntu) testing  Controlled release 

Tangible Results

Permanent Pond Installation • Isolated pond • Limited opportunity for treatment • Use of existing vegetation • Lined sediment forebay • Aquatic bench in permanent pool; ecology, amenity & safety

Native Species Planting Pond Edge Mix Yellow Flag Iris Water Avens Meadowsweet Benefits of bio-retention and enhanced biodiversity 

Learning Points Detailed pre-construction review of EIA Robust planning, management & maintenance required Micro-managed retention & release Maximise use of sub-catchments in design

Thank you