The Conclusions section of a Phase I report

The Conclusions are a list and a statement. The standard requires a Conclusions section that lists every recognized environmental condition, controlled ones included, and every significant data gap tied to the subject property. It also requires the report to carry a statement, called the closing statement on this page, substantially similar to one of two the standard sets out.

What the standard requires

The list. A Conclusions section shall list every recognized environmental condition (REC), controlled RECs (CRECs) among them, and every significant data gap tied to the subject property (E1527-21, 12.7).
The closing statement. The report shall also carry a statement that is substantially similar to one of two the standard words (E1527-21, 12.7). Both forms say three things. First, that a Phase I Environmental Site Assessment of the subject property, identified by address or legal description, was performed in conformance with the practice's scope and limitations. Second, which section of the report describes anything done as an exception to the practice or deleted from it. Third, what the assessment revealed (E1527-21, 12.7.1, 12.7.2).
Its two forms. In one form the third part says the assessment revealed no RECs, no CRECs and no significant data gaps for the subject property (E1527-21, 12.7.1). In the other it says the assessment revealed those that follow, and the list follows (E1527-21, 12.7.2).
What the list does not name. The standard does not count a historical REC as a REC, and a condition judged de minimis is neither a REC nor a CREC (E1527-21, 3.2.20, 3.2.39). The provision on Conclusions names neither among what is listed (E1527-21, 12.7).
Support. Conclusions shall be supported by documentation (E1527-21, 12.2), and the rationale for each class is required in the Opinions (E1527-21, 12.6).
User information not received. Where the user does not pass on the information that is the user's to gather, the environmental professional should consider what its absence means under the Conclusions provision (E1527-21, 6.1).
Only in the suggested format. The standard's appendixes are nonmandatory. The suggested report format in one of them has the Conclusions section also hold recommendations, if requested, and has an executive summary that should not bring in findings, opinions or conclusions found nowhere else in the report (E1527-21, X5.1.3, X5.9). The body of the standard requires neither.

What the federal rule says

The rule has no Conclusions section and no closing statement. It says this of the report:

The results of the inquiry by an environmental professional must be documented in a written report that, at a minimum, includes the following:

40 CFR 312.21(c)

Three things follow in the rule: the professional's opinion on what the inquiry identified, the data gaps and what they mean for that opinion, and the professional's qualifications (40 CFR 312.21(c)). Of data gaps that prevent an opinion, it says:

If there are data gaps such that the environmental professional cannot reach an opinion regarding the identification of conditions indicative of releases and threatened releases, such data gaps must be noted in the environmental professional's opinion in paragraph (c)(1) of this section

40 CFR 312.21(c)(2)

How it is written

In its second form the closing statement introduces the list, so the two read as one passage (E1527-21, 12.7.2). Its first form is the one that reports none (E1527-21, 12.7.1). The standard requires the statement of the report, under its Conclusions provision; it does not say in so many words that the statement sits inside the section (E1527-21, 12.7).

Each entry names a REC, a CREC or a significant data gap as the Opinions named it, and the reasoning stays in the Opinions (E1527-21, 12.6, 12.7).

The statement names the section of the report that describes exceptions and deletions (E1527-21, 12.7.1, 12.7.2). Separately, the standard requires limiting conditions, deletions and deviations to be listed individually and in detail (E1527-21, 12.11).

This page does not reproduce the standard's two statements. They are the standard's own text, at 12.7.1 and 12.7.2.

Example, with the facts in brackets:

[Number]. [The condition, named as in the Opinions]: [the class the professional judges applies]. [The feature and its location on the subject property, in one line.] Rationale at [the Opinions paragraph]; documentation at [the appendix].

Example, with the facts in brackets:

[Number]. Significant data gap: [the information that could not be obtained]. Identified at [the Findings paragraph]; its effect on the opinion is discussed at [the Opinions paragraph].

What a reviewer checks

Does the report have a Conclusions section (E1527-21, 12.7)?
Does the section list every REC and CREC the Opinions name, and every significant data gap the Findings identify (E1527-21, 12.7)?
Does the report carry one of the standard's two closing statements, or one substantially similar (E1527-21, 12.7)?
Does the statement identify the subject property by address or legal description, and name the section that describes exceptions and deletions (E1527-21, 12.7.1, 12.7.2)?
Is each listed item supported by documentation, with its rationale in the Opinions (E1527-21, 12.2, 12.6)?

This page is general reference for environmental professionals. It does not classify any property. ASTM E1527-21 is the standard and is not reproduced here; the judgment of the environmental professional on the facts governs.