Pipleline Integrity Soils Course

1. Introduction
• Introductions
• Course outline
2. Relevance of Soils to Pipeline Integrity
• Pipeline-Soils Corrosion Cell
• groundwater as electrolyte
• pipeline trench environment
• soils-against-the-pipe vs trench wall soils
• oxygen concentration cells
• With respect to Cathodic Protection
• concept of resistivity
• Distinction between site drainage characteristics and textural-types
• the priority of drainage
3. Significant Soil Properties: What makes one textural-type more corrosive than others?
• Distinction between basic soil textural types
• soil-texture triangle, Unified Soils Classification System
• Ionic Content
• sources of ions (weathering, solubility of common minerals)
• the relevance of clay (structure, origin, mineral vs size designation)
• Water Retention Characteristics
• plasticity
• capillary effects
• topographical effects
• With respect to CP
• (soil stresses, landslides)
4. Field Work I: Field Tests for Distinguishing Clays from Silts from Sands
• various feel and taste tests
• “poor-boy” hydrometer
5. The Significance of “Redoximorphic Features” (i.e., mottling and gleying)
• What causes these features?
• How are they related to drainage?
• Definition of “Wetland” and associated features
• Case studies / photo examples
6. Surface Deposits and The Significance of Groundwater Chemistry
• Typical pipeline deposits and their significance
• The Importance of “On-pipe” pH
• Soil pH (influence of vegetation, with respect to corrosivity)
• Groundwater Chemistry
• significance of carbon dioxide
• effects of microbial organisms
• conclusions from recent lab research
7. Field Work II: Sample Collection and Coating Assessment
• site photos
8. Field Work III: Soil Resistivity, and more
• Soil Resistivity (use of Wenner 4-Pin, Soil Box)
• In-ditch P/S readings
• NovaProbe
9. Pre-Field Work Preparation
• Useful on-line sites
• Interpreting Geological and Soils Maps