I get a lot of questions regarding the "shelf life" of a Phase I ESA, when it can be updated, what parts have to be updated, etc. I thought I would reference the ASTM standard in an effort to clarify. Section 4.6 of ASTM E1527-05 (Standard Practice for Environmental Site Assessments; Phase I Environmental Site Assessment Process) discusses the continued viability of an environmental site assessment:
"An environmental site assessement meeting or exceeding this practice and completed less than 180 days prior to the date of acquisition of the property or (for transaction not involving and acquisition) the date of the intended transaction is presumed to be valid."
Translation: the "shelf life" of a Phase I ESA is 180 days (about 6 months). However, the standard goes on to clarify that the Phase I has continued viability if certain conditions are met:
"An environmental site assessment meeting or exceeding this practice and for which the information was collected or updated within one year prior to the date of acquistion of the property or (for transaction not involving an acquisition) the date of the intended transaction may be used provided that the following components of the inquiries were conducted or updated within 180 days of the date of purchase or the date of the intended transaction:
(i) interviews with owners, operators, and occupants;
(ii) searches for recorded environmental cleanup liens
(iii) reviews of federal, tribal, state, and local government records;
(iv) visual inspections of the property and of adjoining properties; and
(v) the declaration by the environmental professional responsible for the assessment or update.
Translation: The original Phase I is valid for 180 days; between 180 days and 1 year, the Phase I is still valid IF items i-v above are updated. If a year passes from when the original Phase I was conducted without updating items i-v, then you have to start from scratch with a new Phase I ESA.