Groundwater Hydrocarbon Sheen vs. Measurable LNAPL

Clear, practical guidance for site owners, developers and environmental managers on recognising a hydrocarbon sheen versus measurable LNAPL in groundwater, when a risk-based duty to notify regulators can be triggered in Australia, and how to manage next steps to reduce transaction, development and compliance risk.

Environmental Delineation Investigation at Industrial Site in Northwest Sydney

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iEnvi completed a Delineation Investigation (DI) at an aerosol and paint manufacturing site in northwest Sydney. The DI installed three groundwater monitoring wells, 13 soil bores and two stormwater points, collecting 8 groundwater, 39 soil and 2 stormwater samples. Findings showed minor soil hydrocarbons (one local exceedance), groundwater elevated dissolved metals likely related to background geochemistry, and isolated vapour-intrusion exceedances — prompting targeted sub‑slab vapour testing and further risk-management recommendations to meet NSW EPA expectations.