670 8-hour HAZWOPER Refresher for Cleanup Operations

On-site Survey Monitoring

• If necessary, use one or more of the following remote sensing or subsurface investigative methods to locate buried wastes or contaminant plumes:
• Electromagnetic induction (EM): Measures subsurface conductivity variations. Locates buried metal objects (drums, tanks, utilities), delineates landfill/waste boundaries, and maps conductive contaminant plumes (e.g., leachate or saline plumes). Fast for areal mapping; good for dissolved-phase plumes in groundwater.
• Seismic reflection/refraction: Uses seismic waves (e.g., from a hammer source) to map subsurface layers, depth to bedrock, and anomalies like buried trenches or waste-filled voids. Can help identify pathways for plume migration (e.g., permeable zones).
• Magnetometry/Magnetics: Detects variations in the Earth's magnetic field caused by ferrous (iron-containing) materials. Ideal for locating buried ferrous drums, tanks, pipes, or metal waste containers. Often used in grids for burial site delineation. Limitations: Only effective for magnetic materials; not for non-ferrous wastes or plumes.
• Direct-Push Technology (DPT): DPT is a minimally invasive subsurface investigative method commonly used. It advances small-diameter tools (typically ≤4 inches) into unconsolidated soils (sand, silt, clay, some gravel) using a combination of hydraulic or percussive force (e.g., percussion hammer) and the weight of the rig (truck-, van-, or track-mounted).
• Laser-Induced Fluorescence (LIF) and Membrane Interface Probes (MIP): LIF and MIP are advanced direct sensing or high-resolution site characterization (HRSC) tools, particularly with direct-push technology (DPT) platforms. They support site characterization by enabling rapid hazard identification, plume mapping, and adaptive decision-making.
• Ground Penetrating Radar (GPR): Uses high-frequency electromagnetic pulses to image subsurface features. Detects buried drums, trenches, voids, landfill boundaries, buried waste pits, and sometimes shallow contaminant plumes (via dielectric contrasts). Excellent for mapping burial trenches and waste boundaries. Limitations: Poor in conductive soils (e.g., clay) or at greater depths.

• Note any indicators of potential exposure to hazardous substances:
• dead fish, animals or vegetation
• dust or spray in the air
• fissures or cracks in solid surfaces that expose deep waste layers
• pools of liquid
• foams or oils on liquid surfaces
• gas generation or effervescence
• deteriorating containers
• cleared land areas or possible landfilled areas

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