ISO 22282-2:2012

Overview

ISO 22282-2:2012, "Geotechnical investigation and testing - Geohydraulic testing - Part 2: Water permeability tests in a borehole using open systems," defines requirements for measuring local permeability of soils and rocks in an open borehole above and below the groundwater level. Intended as part of geotechnical investigation services (in line with EN 1997-1 and EN 1997-2), this standard describes test principles, equipment, test-section preparation, measurement procedures, result interpretation and reporting for water permeability tests in boreholes (open systems).

Key topics

• Test principle and methods
  • Three primary test methods are specified: constant flow rate, variable head, and constant head, each suited to different permeability ranges and site conditions. Tests can be single- or multi-step.
• Equipment requirements
  • Essential items include casing or piezometer, water supply or pump, flow-rate measurement (accuracy ~5% of range), flow control device, perforated tube or filter pack, water-level measurement device (accuracy 0.01 m), and time/recording devices. Calibration and periodic checks are required.
• Test-section preparation
  • Procedures for non-stable and stable soils/rock are provided: options include perforated tubes, filter packs, open-end tests, packers, temporary piezometers and sealing plugs. Specific configurations and shape factors are noted where applicable.
• Unsaturated conditions and pre-saturation
  • Guidance on injecting water to create field-saturated conditions, effects of entrapped air and suction, and recommendations for pre-saturating low-permeability soils to obtain representative results.
• Test procedure and measurements
  • Measurement intervals, stabilization criteria (e.g., consecutive readings within a small change), duration guidance, and recovery measurement rules (start timing, frequency) are specified for each method.
• Results and reporting
  • The standard describes expected outputs (hydraulic head vs. time, flow vs. time), example record formats, interpretation guidance and required field/test report contents.

Applications

ISO 22282-2 is used in site investigation programs where accurate, localized permeability data are needed for:

• Foundation design, retaining structures and earthworks
• Groundwater flow and seepage analyses
• Slope stability and dewatering design
• Hydrogeological characterization for construction, mining and environmental projects

Typical users include geotechnical engineers, hydrogeologists, testing contractors, drilling companies, and geotechnical laboratories seeking consistent, auditable permeability testing in boreholes.

Related standards

• ISO 22282-1 (Geohydraulic testing - General rules)
• ISO 22282 (other parts: water pressure tests in rock, pumping tests, infiltrometer tests, closed systems)
• ISO 22475-1 (Sampling methods and groundwater measurements)
• ISO 14688-1 / ISO 14689-1 (soil and rock identification/classification)
• EN 1997-1 / EN 1997-2 (Geotechnical design / investigation)

Keywords: ISO 22282-2, geotechnical investigation, geohydraulic testing, water permeability tests, borehole testing, open systems, permeability coefficient, constant head, constant flow, variable head.