Input%20for%20Geological%20Risk%20Assessment

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Input for Geological Risk Assessment

• Johannes Klein Jaana Jarva
• April 2008, St. Petersburg

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Risk (technical approach)
The probability of harmful consequences, or
expected losses (deaths, injuries, property,
livelihoods, economic activity disrupted or
environment damaged) resulting from interactions
between natural or human-induced hazards and
vulnerable conditions. Conventionally risk is
expressed by the notation Risk Hazards x
Vulnerability. Some disciplines also include the
concept of exposure to refer particularly to the
physical aspects of vulnerability. (UNISDR 2004)
Risk Hazard x Consequence
Exposure Vulnerability
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Input for the Risk Components

• Hazard
• Type of hazard (geological instability, erosion,
  radon, flood.)
• Probability of occurrence
• Extent and magnitude
• Exposure
• No. of people affected
• No. of buildings affected
• Length of affected network infrastructure (roads,
  pipelines, water supply)
• Vulnerability
• Sensitivity
• Value

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Examples for Vulnerability

• Buildings vulnerability (sensitivity) to
  geological instabilities
• Vulnerability construction type age of
  building height of building maintenance
  single house or row of houses
• Road networks vulnerability to geological
  instabilities
• Vulnerability length importance (condition)
• Peoples vulnerability to Radon
• Vulnerability construction type of building
  drinking water source consumption or radon in
  air

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Input data
SC Mineral?

• Geological Hazards
• Probability, Extent, Magnitude
• Exposure and Vulnerability
• Cadastral data (no. type of houses,
  infrastructure)
• Population density
• Other condition of infrastructure houses,
  distribution of population at day/night

CEP?
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Table of Geological Risks and Vulnerability
Geological Hazard Hazard Parameter Exposed Element Exposure Vulnerability Parameters and Indexes Explanation Sources
Radon Radon concentration in air over threshold Population Population in radon prone area No. of people in unprotected houses Foundation types Slab-on-grade, house with basement, crawl space Vuotilainen, A. and I. Mäkeläinen, 1993 Radon Risk Mapping using Indoor Monitoring Data, Indoor Air 19943, 3, 369-375
Radon Radon concentration in drinking water over threshold Population People using drinking water with radon concentration over threshold Amount of consumed radon affected drinking water Daily drinking water consumption Adults 140 ml/day Children 200 ml/day Ingestion-dose-factor Adults 1x10-8Sv/Bq Children 2x10-8Sv/Bq UNSCEAR 1993 Soruces and Effects of Ionizing Radiation UNSCEAR 1993 Report to the General Assembly
Geological Instability Mapping of ground stability Buildings No. of Buildings Height of buildings, age, construction type, maintenance, aggregation of buildings
See handed out table for more details
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Radon Risk Map
Radon hazard forecast (taken from
the radon-hazard map)
Buildings vulnerability (buildings function
no. of floors)
- 1
Very low 2
Low 3
Medium 4
High 5
Very low 1
Low 2
Medium 3
High 4
Very high 5
Radon Risk
X
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Buildings Vulnerability (first estimates)
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Radon Risk Map
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Weighting of hazards the Delphi method

• Investigations of opinions and ratings from
  hazard and spatial planning experts on importance
  of certain hazard on European scale
• Three round gt average estimation
• Another application on regional scale

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Multi-hazard (multi-risk) mapping

• Summing up of single hazard grid layers gt
  classification of multi-hazards into five classes
  (very high, high, medium, low, very low)
• Using the method of summing up the grids makes it
  possible to look backwards what is the data
  behind the qualitative risk assessment
• See simplified example from Finland used to
  classify construction suitability on the regional
  scale

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Construction suitability data (simplified example
from Finland)

• All data is converted to 25x25 metre grid
• Soil types have classes 1-20, and other mapping
  elements have classes 30-60
• 6 clay, 60 water
• Slope steepness have classes 100-400
• lt 5 100, gt 30 400
• Thickness of fine-grained sediments have classes
  1000-5000
• lt 2,5 m 1000, gt 25 m 5000

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Construction suitability data (2)

• End result Raster map where Quaternary
  geological mapping data slope steepness
  thickness of fine-grained sediments are summed up
• Coding of grids
• 1000 - 5000 thickness
• 100 - 400 slope steepness
• 1 - 16 soil type
• Example Grid-code 3106
• thickness of fine-grained sediments 3000 (
  4,5-13 m)
• slope steepness 100 ( lt5)
• soil type 6 ( clay)

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(No Transcript)
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MURLUMSS

• Multi-Risk Land Use Management Support System
• Map and scenario selection
• Hazard analysis
• Exposed elements analysis
• Vulnerability analysis
• Multiple criteria risk evaluation
• Coping capacity analysis
• Outputs
• Output comparisons between scenarios
• To be partly tested in GeoInforM project?

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Risk factors, hazards (1)

• Geological instability
• Quaternary deposits
• Engineering geology
• Surface, 10 meters level, 20 meters level
• Lithological groups (sand, gravel, peat etc.) gt
  properties thickness
• Sub-groups of rocks
• Hydrogeological properties
• Groundwater level in different aquifers (changes)
• Location of main aquifers
• Piezometric heights
• Neotectonics
• Zones (calculated according to observed events)
• Paleovalleys
• Pre-quaternary reliefs

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Risk factors, hazards (2)

• Radon hazard
• 4 classes (very low, low, medium, high)
• Nature gas generation
• Areas with known natural gas generation
• Areas recommended to be studied further
• Areas with buried hydrological systems (lakes,
  river channels, also artificial formed areas)
• Gas collector wells (risk management) (point
  data)
• Gas generation events (known risk) (point data)

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Risk factors, hazards (3)

• Nature gas generation (4 classes?)
• Areas with known risk
• Areas where further studies are needed
• Areas with buried hydrological systems (natural
  and artificial)
• Areas with managed risk
• Karst formations
• Location
• Surface erosion
• Relevant documents, datasets will be provided by
  SC Mineral

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Risk factors, vulnerability (4)

• Master plan
• Current situation of land use
• Land use in 2015
• Land use in 2025
• Buildings
• Use of building
• Number of floors
• Type of building
• Population density (three options)
• Number of registered residents in buildings
• Estimations based on type of building
• Distribution of population density in the city

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Further work

• The attribute information of selected .shp-files
  will be translated to English
• English translations will be delivered by SC
  Mineral to GTK either as separate tables or as
  .shp-files without any Cyrillic writing by the
  end of May
• GTK will first make proposal for classification
  of geologic instability
• Multi-hazard maps? Weighting of hazards
  Delphi-method?

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Relevance of geological risks

• Results from questionnaire developed in Task 2
• The most important risk according to four
  interviewed groups flooding caused by
  groundwater
• Other relevant risks karst formations and radon
  hazard
• Geological instability?

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Discussion

• Difference between options of experts and people
• Promotion needed