Question 3 of 8: Phase I vs. Phase II Environmental Site Assessments

Question A-3: Phase I vs. Phase II Environmental Site Assessments (20 marks)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

The two phases are sequential and deliberately asymmetric in cost and intrusiveness — Phase I is designed to be cheap and non-destructive so it can be run on every property in a transaction, while Phase II is expensive and intrusive and is only triggered where Phase I has identified a specific reason to look.

Phase I Environmental Site Assessment (ASTM E1527). A non-intrusive desktop and field review: historical records (fire insurance maps, aerial photography, city directories, prior ownership/permits), regulatory database searches (spills, orders, registered contaminated sites on the subject and adjoining properties), a site reconnaissance walkover (staining, stressed vegetation, drums/tanks, odours), and interviews with current/past owners, operators, and local government officials. It produces no soil or groundwater samples and no laboratory data. The deliverable is a list of Recognized Environmental Conditions (RECs) — specific, evidence-based indicators that a release to soil or groundwater may have occurred — and a professional opinion on whether further investigation is warranted. It is used at the start of virtually every commercial real-estate transaction (due diligence for a purchase, financing, or, as in the sale of a foreclosed industrial property, satisfying a lender’s risk requirements) and provides innocent-landowner/all-appropriate-inquiries defence under contaminated-sites liability regimes if no RECs are found.

Phase II Environmental Site Assessment (ASTM E1903). An intrusive investigation triggered specifically by the RECs identified in Phase I — soil borings, test pits, and groundwater monitoring wells targeted at those areas, with samples analyzed at an accredited laboratory for the contaminants plausible given the site’s historical use. It produces quantitative data: contaminant concentrations compared against the applicable regulatory numerical standard for the intended land use, and, where exceedances are found, a first estimate of the lateral/vertical extent of impact. It is used only where Phase I RECs exist (running Phase II without a Phase I basis wastes sampling effort on locations with no evidence-based reason to be impacted), and its outcome directly determines whether the property can be certified clean for the intended use, requires remediation, or needs further delineation (sometimes termed a Phase III investigation).