Digital soil mapping allows one to analyze the relationships between soil corrosion properties and ancillary data (e.g., topographic attributes and remote/proximal sensing data) through several techniques.
Our corrosion maps can be used for corrosion risk assessment, DC/AC interference risk and mitigation, identifying areas that shielding/coating dis-bondment and can potentially cause localized corrosion, leaks, and possible explosions.
The Technical Approach to Constructing A Below-Grade Corrosion Risk Map:
Matergenics GIS’ unique approach to soil mapping considers the following:
- Examination of spatial patterns associated with the physical and chemical properties of soil. This evaluation leads to insights on overall corrosion risk, and answers questions on where to locate a new pipeline and substation infrastructure.
- Identification of the least or most corrosive sites and possible sources of stray current for corrosion mitigation
Some layers that are incorporated into corrosion maps are:
- Soil resistivity
- Soil salinity
- Soil pH
- Soil type, including the clay content
- Drainage characteristics
- Possible presence of stray currents from nearby gas pipelines or other protected assets
Soil properties contributing to corrosion are individually mapped and a proprietary weighting system is used to compare the layers and develop an overall corrosion risk assessment map identifying areas of high, medium and low corrosion. Field surveys are then made to confirm the accuracy of the map. The key to this technology is finding accurate data and the development of an accurate weighting system.
Matergenics will also include maps for gas pipelines and transmission towers (if available), either of which may be a source for stray current corrosion.
Sources of Data
- Matergenics soil databases
- Client’s database, if available
- S. Department of Agriculture
- Soil Survey Geographic Database (SSURGO) – the most detailed level of information for resource management, county planning, etc.
- National Resource Conservation Service
The following demonstrate various examples of soil corrosion mapping for utility structures and pipelines.
A proprietary method is utilized in Matergenics GIS’ corrosion risk assessment. The method includes an algorithm to assign a corrosivity index to each location on the map based on soil properties, geological data, and external corrosion factors. The accuracy of this algorithm has been field tested and proven in several projects.