What are they:
An environmental site assessment is an investigation of a property that is either commercial or industrial in nature to see if they have been environmentally compromised. They take place in three phases. The first phase develops a history of the site to see if there have been any releases of hazardous materials on the site, and its prior uses. Generally, you are required to develop a history of the site dating back to 1940. We investigated one site that required us to go back in history to 1763 as there had been a tannery on the site then. Just about the last thing you would want to own is a former tannery no matter how old. The second phase investigation takes place when on a phase I investigation you discover that indeed a release of hazardous materials has taken place, or is suspected because of the nature of previous usage. A third phase investigation takes place if indeed there is evidence that a release has taken place on the site.
A phase I investigation is the least complicated of the three phases as all that is required is a written report concerning the site. This report would include: The owner's name, the location of the site, prior usage, the site is located on a topo map showing its location, a report on the bedrock geology of the site, a report on the surface geology of the site, the ground water classification of the site, the source of potable water, if there are any nature preserves close by the site, an thorough examination of local, state, and federal records concerning the site, you also report on findings and conclusions concerning the site. The best conclusion is one that simply states that no further environmental work is required.
A phase I investigation is the least expensive of the three. From here the price increases dramatically depending on how much work is required on the site.
A phase II investigation is instituted when the phase I investigation has uncovered the indisputable fact that a release of hazardous materials is suspected or is documented on the site. This consists of taking soil and water samples off the site, and subjecting them to a certified laboratory analysis. If a hazardous material is detected on the site, it is necessary to go on to a phase III investigation.
By the time a site is discovered to be contaminated the buyer has taken off as fast as he can go. The site at that point usually becomes a Brownfield. This is a property that is known to be contaminated. There are special laws concerning Brownfield's.
A phase III investigation is pretty much open-ended as far as its price goes. You never know what you are apt to discover, or where your investigation will lead. In your report you have to give a concise report on the extent of the contamination, and its effect on the health of the environment. At its basics it requires considerable sampling of both the soil and ground water present on the site.
From a phase III investigation you are lead into a remediation plan, which is the most costly of all, and they can amount into millions of dollars.