The ASTM site evaluations come in 2 phases. Phase 1 is much more of a qualitative assessment. What a site investigator would do in the case of an ASTM Phase 1 site investigation is take a lot of pictures of the site from all angles. They would look for damage to the property, vandalism, and overall wear and tear. They would also look at distances from waterways, power lines, main roads, and other businesses or residences. This is important from an environmental standpoint because if the business is located right next to a stream or other body of water, more preventative measures will need to be taken by the owner of the property to ensure that no contamination enters the stream. Also, since there may be surrounding businesses and residences, it can be a high risk for the owner to operate a business that uses volatile substances or fine particulates. For example, a painting business for cars, bikes, trucks, etc. would be more likely to accidentally discharge paint spray dust among other particulates into the atmosphere because of poor air filtration and exhaust ventilation maintenance. The investigator will also look inside the facility at the general condition of the building, and will look to see if there are any processes that could lead to environmental contamination. During an ASTM Phase 1 site evaluation, things like lead paint, water and soil contamination, asbestos, molds, and other environmental and occupational hazards will be taken note of, but not tested until a Phase 2 site investigation.
An ASTM Phase 2 site investigation is the more qualitative portion of the site investigations done through ASTM. This investigation involves soil boring, water and air sample collecting, spore collecting and other field testing to check if the identified potential hazards in a Phase 1 truly are hazardous. It will also tell the potential buyer if there is a history of dumping of toxic or environmentally harmful wastes on the site, if there has been any groundwater contamination that is likely, and even if there has been a major discharge of contaminated air since many of those particulates can settle to the ground around the facility.
The AAI Rule differs from ASTM in that it is a site evaluation standard directly from the EPA. The EPA AAI final rule is very similar to ASTM though. It borrows many of the same procedures as a phase 1 and phase 2 investigation, but it lumps them into 1 site evaluation. Also, since the EPA is the one who is investigating the site, they are able to go further into the records of the site owner to understand if they are innocent or guilty of violation of various codes and laws. This rule was under scrutiny that it was not thorough and stringent enough compared to ASTM to warrant the two being done by different organizations, but the EPA AAI Final Rule is being revised. If it is accepted, it will become the overall standard for site investigations nationwide.
https://www.epa.gov/sites/production/files/2014-08/documents/aai-reporting-fact-sheet-and-checklist-062111-final.pdf
http://www.epa.nsw.gov.au/clm/
http://dnr.wi.gov/files/pdf/pubs/am/am465.pdf
