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Showing posts from May, 2018

Groundwater Elevation and Contaminant Levels, Cause & Effect?

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Groundwater Elevation and Contaminant Levels, cause and effect? Over the years I've heard a lot of explanations regarding groundwater elevations and subsequent increases and/or decreases in contaminant levels and the presence and disappearance of free product. I've heard people argue that increasing water levels increases contamination, and I've also heard the opposite. The question or debate is does groundwater elevation influence contaminant levels? Furthermore, does groundwater elevation influence the presence or absence of free product? I've been doing this kind of work for about 31 years now, and I've learned enough to know that it all depends on the specific site and even the specific well. These are a question of correlation or causation. Webster's Dictionary defines correlation as: "a relation existing between phenomena or things or between mathematical or statistical variables which tend to vary, be associated, or occur together in

Remediation May Be Overrated

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Selecting a remedial approach can be a complicated task. The process is based on identifying desired clean-up goals, sensitive issues that could affect a remediation strategy (e.g. proximity to drinking water wells, surface waters, other sensitive receptors or public perception/relations), and costs. Each site presents different decisions and uncertainties regarding remediation options. The four main steps are 1) delineation, 2) risk evaluation, 3) feasibility, and 4) cost. The companies that understand the process and also work to keep it simple, end up selecting the more effective and least costly solutions. When estimating remedial action, estimates should provide for a relative comparison of costs between all the feasible alternatives. Alternatives that are not feasible should not be included. These estimated costs should be detailed and accurate. Costs that will be incurred in the future should be identified and noted for the year in which they will occur. The distribu