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More information on selected environmental geology case studies:

Membrane Interface Probe (MIP)

Fugro has successfully combined our Cone PenetrationTesting technologies (CPT) with the Membrane Interface Probe (MIP). The combination of CPT and MIP provides our clients with highly accurate lithology and hydrogeologic data from our cone penetrometers and continuous in-situ screening of the subsurface media for volatile organic compounds (VOCs). All CPT and MIP data is recorded on computers mounted inside the CPT rig. The collected data is presented in real-time and is plotted in the field immediately upon completion of each sounding – allowing subsequent test locations to be determined onsite based upon collected data.

The MIP probe is comprised of a hydrophobic, semi-permeable membrane located immediately above the cone penetrometer. This membrane is surrounded and inset in a heater block. During test, the heater block is used to maintain a constant temperature greater than 100º Celsius around the membrane. This heat volatilizes any VOCs near the membrane and creates a pressure gradient that causes the VOCs to diffuse across the membrane. Once across the membrane, the VOCs are “swept” by an inert carrier gas to a series of chemical detectors located in the CPT rig. The detectors we typically use are a Flame Ionized Detector (FID), Photo Ionized Detector (PID) and a Dry Electrolytic Conductivity Detector (DELCD) or Electron Capture Detector (ECD).


These detectors are selected because they identify a wide range of VOCs including but not limited to petroleum hydrocarbons (BTEX), chlorinated hydrocarbons (TCE, PCE, VC) and aliphatics (methane).

GeODin provides the optimal software for presenting the results of MIP investigations with a set of specially designed import filters and templates combining lithology with chemical profiles.