We are testing a new beta website for gov.scot go to new site

Peat Landslide Hazard and Risk Assessments: Best Practice Guide for Proposed Electricity Generation Developments

DescriptionThe Peat Hazard and Risk Assessment Guide provides best practice methods to identify, mitigate and manage peat slide hazards and associated risks in respect of consent applications for electricity generation projects in Scotland.
ISBN
Official Print Publication DateJanuary 2007
Website Publication DateJanuary 26, 2007

Listen

Please refer to the second edition of this guidance (April 2017) published at http://www.gov.scot/Publications/2017/04/8868.

 

THE FOLLOWING GUIDANCE HAS BEEN SUPERSEDED BY A SECOND EDITION PUBLISHED 26 APRIL, 2017. THE VERSION FROM JANUARY 2007 WILL BE RETAINED FOR ARCHIVAL PURPOSES.

 

ISBN 0 7559 6378 4
This document is also available in pdf format (1.1MB)

Contents

1 Introduction
1.1 Purpose
1.2 Guidance objectives
1.3 Context
1.4 Scope of document
1.5 Information Requirement
1.6 ECU Assessment Services
1.7 Developer Design Team
1.8 Checklist for peat landslide hazard assessment

2 An overview of peat landslide mechanisms
2.1 Mechanisms and morphology of peat landslides
2.2 Preparatory factors for peat instability
2.3 Triggering factors
2.4 Pre-failure indicators of instability

3 Desk Study
3.1 Overview
3.2 Review of existing site information
3.3 Site reconnaissance survey

4 Ground investigation and design
4.1 Objectives
4.2 Geomorphological mapping
4.3 Field sampling
4.4 Intrusive investigation techniques
4.5 Non-intrusive (geophysical) techniques
4.6 Laboratory testing schedule
4.7 Site instrumentation and monitoring regimes

5 Stability assessment, hazard ranking and reporting requirements
5.1 Overview
5.2 Slope stability analyses
5.3 Hazard and risk ranking
5.4 Quantitative Risk Assessment ( QRA)
5.5 Mitigation
5.6 Reporting
5.7 Further reading
5.8 Acknowledgements

6 References

List of Tables
Table 3.1. Recommended sources of mapping
Table 5.1. Qualitative assessment of peat landslide Hazard for the lifetime of the development
Table 5.2. Qualitative assessment of peat landslide Exposure for the lifetime of the development
Table 5.3. Hazard Ranking and suggested actions

List of Figures
Figure 1.1. Flow diagram checklist for peat landslide hazard assessment
Figure 3.1. Flow diagram, indicating requirement for detailed ground investigation
Figure 5.1. Balance of slope forces
Figure 5.2. Qualitative Hazard Ranking methodology
Figure B.1. Plan showing the location of geophysical traverses on a proposed turbine base the Farr Wind Farm, Scotland. These included Ground Penetrating Radar ( GPR), resistivity ® and P-wave Seismic
Figure B.2. Results of a GPR Survey, Farr Wind Farm, showing peat stratigraphy. Fibrous peat overlies amorphous peat (yellow line) which in turn overlies compacted glacial till (red line)
Figure B.3. Results and interpretation of resistivity and P-wave seismic geophysical survey undertaken at Farr Wind Farm, Scotland, showing a horizontally stratified sequences (verified by drilling and trial pitting)

List of Plates
Plate 2.1. Bog burst, a spreading failure in peat with pear shaped area of disturbance with concentric rafts and tears and little substrate exposed
Plate 2.2. Peat slide, a shallow translational slide failure in peat with large slab-shaped raft visible (right) and extensive exposed substrate (left)
Plate 2.3. Long and semi-continuous tension crack
Plate 2.4. Diamond shaped tears
Plate 2.5. Multiple intersecting cracks
Plate 2.6. Compression ridge
Plate 2.7. A section of thrusted peat
Plate 2.8. Extrusion features
Plate 2.9. Pipe outlet in exposed peat scarp
Plate 2.10. Collapsed piping
Plate 2.11. Gullies, and pools and hummocks
Plate 2.12. Flushes and soakaway

Appendices

Appendix A. Sources of satellite imagery
Appendix B. Geophysical survey techniques
Appendix C. Site monitoring instrumentation