Environmental Site Assessment Guidelines - Ohio Department of ...

with the highest field reading should be sent for analysis. If the field readings are inconclusive,
then the sample exhibiting the highest amount of visual, or other signs of contamination, is sent
for analysis. If this information is inconclusive, then the sample obtained at the soil/water
interface should be sent for analysis. If groundwater is not encountered, then the sample from
the terminal depth of boring for that parcel should be sent for analysis.
It should be noted that there may be cases where multiple samples per boring are analyzed,
(i.e. the sample which shows the most contamination, the highest field screening value, the
most staining, or the most olfactory evidence) and the sample collected at the bottom of the
boring may be sent to the analytical laboratory for analysis. Submitting multiple samples per
boring requires prior approval from OES.
The field screening and sampling discussion needs to include the methods and instruments to
collect the following pertinent data from a MW prior to sampling groundwater. Each MW should
have the static water level collected to determine if free product is present, and the free
product’s thickness if it is present. This information is typically collected by using an Interface
probe or other water level measuring devices. For sites that will be wholly acquired and
multiple MWs placed, each MW should have its top-of-casing elevation measured and surveyed
in order to produce a potentiometric map.
8.1.2.4 Analytical Methods
Analytical methods for environmental samples must be provided. These parameters must be in
accordance with Test Methods for Evaluating Solid Waste SW-846 prepared by the USEPA. In
the event other test methods are proposed, justification and supporting information must be
provided in the Phase II ESA Work Plan. The ODOT ESA Unit must also approve these
methods.
8.1.2.5 Quality Assurance/Quality Control
Proposed QA/QC (Quality Assurance/Quality Control) procedures should be included to allow
for assessment of the quality of the data collected. QA/QC measures may include written
decontamination procedures, instrument calibration, the preparation and analysis of trip blanks,
equipment blanks, duplicate samples, and/or other types of QA/QC samples.
8.1.2.6 Geophysical Survey
A geophysical survey may be conducted on parcels that are suspected of having buried
concerns such as USTs and drums where their locations are not known. A geophysical survey
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