Pennaf Housing Group

Edelweiss, Colwyn Bay

Introduction

The Edelweiss site in Colwyn Bay, previously developed and historically used for mining and industrial purposes, was proposed for redevelopment into residential apartments.

The site’s history, ground conditions, and potential contamination risks necessitated a comprehensive geotechnical and environmental assessment to inform safe and sustainable development.

Client

Pennaf Housing Group

Sector/ Project Type

Developers - Desk Study Risk Assessment, Geo Technical.

Date

2018

Location

Colwyn Bay, Conwy

Our Approach

A phased investigation was undertaken, beginning with a desk study to assess historical land use, contamination sources, and environmental risks.

This was followed by an intrusive site investigation, including trial pits, boreholes, dynamic probes, and laboratory testing for geotechnical and chemical properties.

The approach prioritized identifying ground conditions, contamination risks, and utility locations, with reference to relevant British and Welsh standards.

The Solutions

The investigation revealed variable fill, including building rubble and stone, with isolated contamination (notably sulphate and PAHs). Most material was classified as non-hazardous, though remediation was required for specific hotspots.

Foundation solutions recommended piled foundations due to fill depth and proximity to retaining walls, with DS-1 or DS-3 class concrete specified for sulphate-affected areas. Basic radon protection and soakaway feasibility were addressed, and utility diversions planned to accommodate new construction.

Project Outcomes

The site was deemed suitable for redevelopment, with risks managed through targeted remediation, robust foundation design, and ongoing contamination monitoring.

The approach ensured compliance with environmental and building regulations, minimized hazards to future residents, and supported the delivery of 31 new apartments with associated infrastructure.

Our Work

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