35 Ill. Adm. Code 740.425
Site Investigation Report – Comprehensive Site Investigation
Section 740
Section 740.425 Site
Investigation Report – Comprehensive Site Investigation
a) Site investigation results for both phase I and phase II of
the comprehensive site investigation shall be combined into one Site
Investigation Report.
b) A Site Investigation Report for a comprehensive site
investigation shall include, but not be limited to, the following chapters:
1) Executive summary. This chapter shall identify the objectives
of the site investigation and the technical approach utilized to meet such
objectives. It shall state whether recognized environmental conditions were
identified and the data limitations in the assessment;
2) Site characterization. This chapter shall include the
compilation of all sources reviewed and information obtained as a result of the
site investigation under Section 740.420 of this Part, including but not
limited to:
A) Sources consulted or reviewed. This subchapter shall contain a
list of reference documents used in completing the site investigation;
B) Site history. This subchapter shall present a chronological
summary of the historic uses of the remediation site as prescribed by
"Standard Practice for Environmental Site Assessments: Phase I
Environmental Site Assessment Process" (ASTM E 1527-00), incorporated by
reference at Section 740.125 of this Part;
C) Site description. This subchapter shall describe the regional
location, pertinent boundary features, general facility physiography, geology,
hydrogeology, existing and potential migration pathways and exposure routes,
and current and post-remediation uses of the remediation site and surrounding
areas that are immediately adjacent to the remediation site;
D) Site base map(s) meeting the requirements of Section
740.210(a)(7) and including the following:
i) The sources or potential sources of the contaminants of
concern, spill areas, and other suspected areas for any or all contaminants of
concern;
ii) On-site and off-site injection and withdrawal wells; and
iii) All buildings, tanks, piles, utilities, paved areas,
easements, rights-of-way and other features, including all known past and
current product and waste underground tanks or piping; and
E) A legal description or reference to a plat showing the
boundaries of the remediation site, or, for a Federal Landholding Entity, a
common address, notations in any available facility master land use plan, site
specific GIS or GPS coordinates, plat maps, or any other means that identifies
the site in question with particularity;
3) Site-specific sampling plan. This chapter shall indicate
those applicable physical and chemical methods utilized for contaminant source
investigations, soil and sediment investigations, hydrogeological
investigations, surface water investigations, and potential receptor investigations;
4) Documentation of field activities. This chapter shall include
the results of the field activities to determine physical characteristics. At
a minimum, this chapter shall include the following elements:
A) Narrative description of the field activities conducted during
the investigation;
B) The quality assurance project plan utilized to document all
monitoring procedures (e.g., sampling, field measurements and sample analyses)
performed during the investigation, so as to ensure that all information, data
and resulting decisions are technically sound, statistically valid, and
properly documented; and
C) Presentation of the data in an appropriate format (e.g.,
tabular and graphical displays) such that all information is organized and
presented logically and that relationships between the different investigations
for each medium are apparent;
5) Endangerment assessment. This chapter shall analyze the
results of the field activities and characterize the extent of contamination
(qualitative and quantitative) for contaminants of concern and compare the
remediation site information with the applicable provisions of 35 Ill. Adm.
Code 742. This chapter shall:
A) Describe any recognized environmental conditions, evaluate
exposure routes, including threatened releases, and evaluate exposure routes
excluded under 35 Ill. Adm. Code 742;
B) Describe all conditions the LPE has determined to be de minimis
along with the rationale for each such de minimis determination;
C) Describe the nature, concentration and extent of contaminants
of concern within all environmental media at the remediation site and assess
the observed and potential contaminant fate and transport;
D) Describe the significant physical features of the remediation
site and vicinity that may affect contaminant transport and risk to human
health, safety and the environment; and
E) Compare the concentrations of the contaminants of concern with
the corresponding Tier 1 remediation objectives under 35 Ill. Adm. Code 742;
6) Conclusion. This chapter shall assess the sufficiency of the
data in the report and recommend future steps;
7) Appendices. References and data sources, including but not
limited to field logs, well logs, and reports of laboratory analyses, shall be
incorporated into the appendices with reports containing laboratory analyses of
samples collected on or after January 1, 2003, including the following:
A) Accreditation status of the laboratory performing the
quantitative analyses;
B) Certification by an authorized agent of the laboratory that all
analyses have been performed in accordance with the requirements of 35 Ill.
Adm. Code 186 and the scope of accreditation; and
8) Licensed Professional Engineer affirmation in accordance with
Section 740.410 of this Part.