Current through Register Vol. 48, No. 38, September 20, 2024
a) Investigation Due to Off-Site Impact. When
required in writing by OSFM, owners or operators of USTs shall follow the
procedures in Subpart C to determine if the UST is the source of off-site
impacts. These impacts include the discovery of regulated substances, such as
the presence of free product or vapors in soils, basements, sewer or utility
lines or nearby surface or drinking water that have been observed by OSFM or
brought to its attention by another party.
b) Release Investigations and Confirmation
Steps. Unless corrective action is initiated in accordance with 35 Ill. Adm.
Code 734, owners or operators shall immediately investigate and within 7 days
shall confirm the presence or absence of all suspected releases of regulated
substances requiring reporting, using the following procedures:
1) System Test. Owners and operators must
conduct tests (according to the requirements for precision testing in 41 Ill.
Adm. Code
175.630(b)
and 175.640(a)(4) or, as appropriate, secondary containment testing described
in 41 Ill. Adm. Code
175.700(d).)
A) The test must determine whether:
i) A leak exists in that portion of the tank
that routinely contains product, or the attached delivery piping; or
ii) A breach of either wall of the secondary
containment has occurred.
B) If the system test confirms a leak into
the interstice or a release, owners and operators shall repair, replace,
upgrade or decommission the UST. In addition, owners and operators shall begin
corrective action pursuant to 35 Ill. Adm. Code 734 if the test results for the
system, tank or delivery piping indicate that a release exists;
2) Further investigation is not
required if the test results for the tank system and delivery piping do not
indicate that a release exists and if environmental contamination is not the
basis for suspecting a release; and
3) Owners or operators shall conduct a site
assessment (utilizing the requirements of Section
176.330
) if environmental contamination is the basis for suspecting a release. In the
event lab results are not forthcoming within 7 days, the owner/operator shall
have such reasonable additional time as is necessary to receive the results,
but the total time period to confirm the presence or absence of a release and
report any confirmed release shall not in any event exceed 45 days.
c) Initial Site Assessment. An
initial site assessment shall follow the procedures and requirements identified
in Section 176.330.
1) If the site assessment
results for the excavation zone or the UST site indicate that a release has
occurred, owners or operators shall begin initial response and initial
abatement procedures under Sections
176.350
and
176.320(b)
and (c), and begin corrective action pursuant
to 35 Ill. Adm. Code 734.
2) If the
site assessment results for the excavation zone or the UST site do not indicate
that a release has occurred, further investigation is not required.
