A contractor excavating near the Cataraqui River hit water at 3 meters and the pumps couldn't keep up. The original geotechnical report classified the soil as 'silty till' but never quantified how fast water moves through it. That project lost two weeks. In Kingston, where fractured limestone and glacial till dominate, guessing permeability is a gamble. The Lefranc test measures hydraulic conductivity in soil directly in the borehole, at the depth that matters. The Lugeon test does the same for rock mass, injecting water under pressure in packed-off intervals. Both methods deliver the k-value engineers need for dewatering design, contaminant transport modeling, or grouting programs. Our team runs these tests across Frontenac County, from downtown Kingston high-rises to rural subdivisions near Westbrook, always referencing ASTM D6391 for the Lefranc method and the classic Lugeon procedure from Houlsby (1976). Before mobilizing a pump test, many consultants pair this data with a grain-size analysis to cross-check field results against Hazen correlations.
A single Lefranc test at the right depth reveals more about real drainage behavior than twenty lab permeameter runs on disturbed samples.
Our approach and scope
Site-specific factors
Dewatering design based on textbook values fails in Kingston because the limestone fracture network is unpredictable. A Lugeon test can show high water take at 10 meters and nearly impermeable rock at 12 meters. If you skip field testing and assume a uniform k, your well points are placed blind. The result: a flooded excavation or, worse, destabilization of the adjacent highway embankment. The Laurentian Great Lakes influence means groundwater levels respond to seasonal lake-level cycles, adding another variable. Our test intervals target the specific horizons the excavation will intersect, providing a vertical profile of permeability. For projects near the Rideau Canal or in the Cataraqui watershed, this data is not optional, it is the basis for a defensible dewatering plan and a permit application that holds up to review by the Cataraqui Region Conservation Authority.
Regulatory framework
ASTM D6391-11: Standard Test Method for Field Measurement of Hydraulic Conductivity Using Borehole Infiltration, Houlsby (1976) routine Lugeon test procedure, CSA A23.3 (concrete structures, referencing groundwater considerations for durability)
Related services
Lefranc Permeability Tests in Soil
Constant-head and falling-head tests in boreholes to determine hydraulic conductivity of overburden soils. We target specific strata, from upper weathered till to deeper sand and gravel lenses. Results used for dewatering system design, settlement rate analysis, and contaminant flow modeling.
Lugeon Tests in Fractured Rock
Five-stage pressure injection tests in NQ or HQ cored boreholes to assess rock mass permeability. We measure water take in Lugeon units, interpret fracture behavior (dilation, washout, laminar flow), and provide the data required for grouting design and deep excavation planning in limestone.
Typical parameters
Common questions
What does a field permeability test cost in Kingston?
The cost for a Lefranc or Lugeon test program typically ranges from CA$740 to CA$1,250 per test interval, depending on access, depth, and the number of intervals tested in a single mobilization. A complete site investigation with multiple boreholes and test depths will be priced based on the specific scope of work.
When do I need a Lugeon test instead of a Lefranc test?
You need a Lugeon test when the foundation or excavation intersects fractured rock, which in Kingston is almost always the Gull River Formation limestone. The Lefranc test is for soil and highly weathered rock. If the borehole log shows RQD above 20%, a Lugeon test is the correct tool to quantify fracture permeability and guide any grouting decisions.
How long does a single Lefranc or Lugeon test take to complete?
A single Lefranc test interval takes about 30 to 60 minutes once the borehole is prepared. A full five-stage Lugeon test in rock typically requires 60 to 90 minutes per interval, because each pressure stage must reach steady flow before recording data. We usually schedule one to two days for a complete program of four to six test intervals.