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VI. PERMANENT CLOSURE
A. Planning For Permanent Closure
Where the owner and operator intends to permanently close an UST system, the following
pre-closure planning steps should be taken:
1. If the tank(s) are required to be registered and they are not, submit a "Registration
of Storage Tanks" form, with a fee of $50.00 per tank, to the appropriate regional
office of the department. On the form, complete information for all regulated storage
tanks at the facility, including those to be permanently closed.
2. Hire a DEP-certified installer who has UMR certification to conduct tank handling
activities.
3. Make sure that the certified installer and any of their subcontractors have:
a. A Site-Specific Health and Safety Plan which includes:
(1) Familiarity with and adherence to all applicable Occupational Health and Safety
Administration (OSHA) and National Institute for Occupational Safety and Health (NIOSH)
regulations and recommendations. A complete discussion of OSHA and NIOSH requirements
that may be applicable to closure activities is beyond the scope of this guidance.
However, the following closure procedures may be relevant:
- OSHA 2226 - Excavations
- OSHA, 29 CFR Part 1926, Occupational Safety and Health Standards-Excavations
- OSHA, 29 CFR Part 1910, Occupational Safety and Health Standards
- The NIOSH "Criteria for a Recommended Standard*** Working in Confined Space"
may be used as guidance for conducting safe closure procedures at some hazardous
substance tanks.
(2) Locating underground utilities prior to excavation or drilling. Prior to beginning
any excavation or drilling activities the person(s) conducting the closure should
be familiar with the location of buried utilities as well as other tanks and piping
that may be present at the facility. The Underground Utility Line Protection Law
(Act 172 of 1986) requires that anyone planning excavations or borings call Pennsylvania
ONE-CALL at 1-800-242-1776 at least three, but not more than ten business days, prior
to conducting excavation or drilling activities. Once notified, if there are public
utilities in the area of the planned excavation or drilling activity, the utilities
will mark their lines.
(3) Procedures or provisions to avoid contact with overhead utility lines by heavy
equipment.
(4) Restricting site access from vehicular or pedestrian traffic by utiliz-ing fencing,
similar barriers, security patrols or warning signs.
(5) Monitoring for and mitigating flammable vapors.
(6) Elimination of ignition sources by not smoking and utilizing hand tools (shovels,
wrenches, hammers) made of spark-proof materials such as beryllium, power tools which
are explosion proof and flash-lights which are intrinsically safe.
(7) The availability of a fire extinguisher at the job site which is capable of extinguishing
all types of fires.
(8) The provision for the wearing of appropriate personnel protective equipment.
(9) Procedures for addressing emergency situations such as fire or explosion, injury
and environmental incident. Include a map show-ing directions to the nearest hospital
as well as emergency telephone numbers.
b. Made provisions for Tank Cleaning and Waste Handling which includes:
(1) A plan for containing small spills from disconnecting piping.
(2) A method for purging or inerting the tank.
(3) A method for cleaning the tank if performed on site.
(4) A plan for the handling of tank liquids and sludges.
(5) A process to excavate, identify and properly stockpile uncontami-nat-ed and contaminated
soil.
(6) A plan for tank system removal.
4. Make sure that the person(s) conducting the Waste Management and Disposal activities
has/have:
a. If the tank is to be cleaned off-site, a plan for transporting the tank to a permitted
processing, treatment, storage or disposal facility, and complying with PennDOT regulations.
b. A plan for the management and disposal of tank liquids and sludges.
c. A plan for transportation of the cleaned tank after removal and the disposition
of the tank.
d. A plan to remediate and/or dispose of contaminated soil.
5. Determine who is going to conduct the site assessment.
6. Make sure that the person(s) conducting the site assessment has/have:
a. A Site Assessment Plan which includes:
(1) Visual assessment procedures.
(2) Field test and field instrument procedures.
(3) Sample collection procedures and sample preservation methods, including chain-of-custody
procedures and documentation.
(4) Decontamination procedures used on sampling and drilling equipment.
7. At least 30 days prior to initiating permanent closure of state and federally
regulated UST systems, notify the department of the intent to permanently close utilizing
the "Underground Storage Tank System Closure Notification" form found in
Attachment 3. A copy of this form must also be sent to the Pennsyl-vania State Police,
Fire Marshal Division, or to the appropriate agency in Philadelphia or Allegheny
County, if the tank is governed by their flammable and combustible liquid regulations.
8. Use as much product in the tank as possible.
9. Identify and comply with any local ordinances governing UST system closures.
A "Planning for Permanent Closure Checklist" can be found in Attachment
2. This check-list is intended to assist the owner and operator in the closure planning
process.
B. Tank Handling/Waste Management
and Disposal Activities
Where possible, the department recommends that all UST systems be removed from the
ground. However, the department recognizes that closure-in-place may be neces-sary
where an UST system is under a permanent structure and removal would damage that
structure. Certified installers and tank owners and operators are referred to the
following tank handling procedures when permanently closing an UST system:
- American Petroleum Institute Recommended Practice 1604, "Removal and Disposal
of Used Underground Petroleum Storage Tanks"
- American Petroleum Institute Publication 2015, "Cleaning Petroleum Storage
Tanks"
These publications are available from the American Petroleum Institute (API), 1220
L Street, Northwest, Washington, DC 20005, telephone 202-682-8375.
In addition to the API publications, certified installers and tank owners and operators
should be aware of the following:
1. Soil Excavation
If an UST system is being permanently closed by removal from the ground, the certified
installer should initially excavate only that amount of soil and backfill material
necessary to remove the tank and piping. Once the tank system is removed from the
ground, removal of any soil beyond three feet from the tank and piping in any direction
will be considered as remedial activity and will not require the use of a certified
installer.
Excavated soils must be segregated (i.e. obviously contami-nated, not suspected to
be contaminated). This may be accomplished by visual observation and by field screening
the soils as they are excavated through the use of field instruments such as photoionization
detectors, flame ionization detectors, portable gas chromatographs and other appropriate
field measure-ment procedures. Segregation of soils during excavation will facilitate
laboratory testing, treatment and disposal. Note, however, where soil has been
segregated into presumably contaminated and uncontaminated piles, the soil which
is presumably uncontaminated must be sampled prior to reuse on-site in order to confirm
that it is uncontaminated. See Section VI.C.1.d.(5), page 21, "Soil Pile Sampling."
It is also recommended that excavated soils be segregated from concrete and asphalt
material.
2. Classification of Wastes
The wastes associated with the permanent closure of UST systems include residual
and possibly hazardous wastes. Wastes may include the tank itself, along with any
associated piping, unusable product, sludges and sediments, condensation water, wastewater
associated with cleaning the tank, and contaminated soil removed from the excavation.
A classification of these wastes as either residual or hazardous should be made based
on the following:
a. Tank, Piping and Contents
Emptied and Cleaned - A storage tank is considered "empty" when
no more than 1 inch (or .3 percent by weight of its total capacity) of residue remains
in the tank. A tank and piping is considered "cleaned" when all remaining
residue has been removed using applicable industry standards to clean that type of
storage unit. A tank and piping which has been emptied and cleaned is considered
scrap metal and, if it is to be recycled or reused, is specifically excluded from
being a hazardous waste (25 Pa. Code §261.4(a)(21), relating to exclusions)
or residual waste (25 Pa. Code §287.1, relating to definition of coproduct and
waste). An emptied and cleaned tank which will not be recycled or reused, but is
destined for disposal in a landfill, is regulated as a residual waste.
Emptied but not Cleaned - A petroleum storage tank, which meets the above
definition of "empty", but has not been cleaned, is excluded as a hazardous
waste, provided the tank and contents do not fail the test for any characteris-tic
from D001 through D017 (see 25 Pa. Code §261.4(a)(17)). If excluded as a hazardous
waste, the tank and contents are a residual waste. Most petroleum storage tanks,
with the exception of those containing gasoline residues, which may fail the test
for ignitability (D001) or lead (D008), fall into the category of petroleum contaminated
media and debris and are excluded as hazardous waste and regulated as a residual
waste.
In the case of a tank which stored a hazardous substance, or a petroleum storage
tank which contains a substance that fails the test for any characteristic from D001
through D017, the tank contents are not subject to regulation as a hazardous waste
until the waste exits the tank in which it was generated, or remains in the tank
for a period of more than 90 days after the tank ceased to be operated as a storage
tank (see 25 Pa. Code § 261.3(e)).
Not Empty - A petroleum or hazardous substance storage tank and its contents
are not subject to regulation as a hazardous waste for a period of 90 days after
closure or until the waste exits the storage tank, which-ever comes first (25 Pa.
Code § 261.3(e)). The classification of the contents upon exit from the tank
or after 90 days has elapsed is dependent on the results of a hazardous waste determination
provided the contents are not usable product. When it is not immediately possible
to determine if a material is a hazardous waste, the material must be managed as
a hazardous waste until a deter-mination is made which indicates it is not (25 Pa.
Code § 261.3(g)).
b. Unusable product, sludges and sediments, tank bottoms and waste-water - These
wastes from inside the storage tank are hazardous if they meet any of the hazardous
waste criteria in Chapter 261. If the tank contained gasoline it should be assumed
the wastes are hazardous. If the wastes are determined to be non-hazardous, they
are subject to regulation as a residual waste.
c. Contaminated Soil - Petroleum contaminated soil is regulated as a residual waste
(25 Pa. Code §287.2(c)(4), relating to scope) provided it does not meet any
of the hazardous waste criteria in Chapter 261 or if it is specifically excluded
from regulation as a hazardous waste (25 Pa. Code §261.4(a)(17)). Soils contaminated
with products that appear on the hazardous waste lists of commercial chemical products
are subject to regulation as a hazardous waste.
d. Recovered or reclaimed product - Any virgin product recovered directly from the
tank, if used, is considered a product and is not regulated as a waste. In addition,
any material reclaimed from tank bottoms that qualifies as a coproduct, is not regulated
as a waste.
3. On-site Storage of Contaminated
Soil
Contaminated soils removed from the excavation during a tank removal that are residual
waste must be stored in accordance with applicable sections of 25 Pa. Code §§299.101-299.154
(relating to standards for storage of residual waste) of the residual waste management
regulations and other applicable department regula-tions. In addition to the general
requirements set forth in §299.131(a), 25 Pa. Code §245.308(d) (relating
to on-site storage of contaminated soil) of the regulations to administer the storage
tank and spill prevention program requires that contaminated soil piles be completely
and securely covered, for the duration of the storage period, with an impermeable
material of sufficient strength, thickness, anchoring or weighting to prevent tearing
or lifting of the cover, infiltration of precipitation or surface water runon, and
exposure of the soil to the atmosphere. In addition to the nuisance control requirements
set forth in §299.115(b), 25 Pa. Code §245.308(d) also requires that appropriate
steps be taken to deter public access to the storage area. This may include fencing,
similar barriers, security patrols or warning signs.
Where excavated contaminated soil is stored on-site, 25 Pa. Code §245.308(c)
requires that the excavated soil be disposed of or active treatment of the excavated
soil be initiated, within 90 days from the first day of storage, unless extended
by the department in writing. Extension requests must be submitted in writing to
the appropriate DEP regional office. The depart-ment may require immediate removal
of contaminated soil if the soil is not being properly stored or managed, or if the
department determines that storage poses a threat to human health, safety or the
environment (25 Pa. Code §245.308(e)).
Contaminated soils that are hazardous waste must be stored in accordance with 25
Pa. Code §262.34 (relating to accumulation) of the hazardous waste management
regulations. Hazardous waste cannot be stored for more than 90 days without a permit
from DEP's Bureau of Land Recycling and Waste Management. Extensions under Chapter
245.308(c) do not apply to hazardous waste.
4. Tank Cleaning
USTs may be cleaned at the closure site or moved to another location for cleaning.
However, the department recommends that USTs be cleaned prior to removal from the
excavation to eliminate the potential for releases. In either case, the tank owner
is considered the generator of the wastes. If the wastes are hazardous, the owner
must obtain a provisional generator I.D. Number from DEPís Division of Reporting
and Fee Collection by telephoning 717-783-9258. If the USTs are cleaned at the closure
site, use extreme care to safely and properly purge the USTs of explosive vapors
prior to accessing the USTs for cleaning. If the USTs are to be moved to another
location for cleaning, see the waste transportation requirements in Section VI.B.6.
below.
5. Tank Removal
When a tank is to be removed from the ground, provisions should be made in order
to safely lift it out of the excavation. One of the major dangers in tank removals
is when the lifting chain is not properly attached to the tank and the chain snaps
back under tension. The lifting chain should be attached to an existing lifting lug
on the tank or a lifting plug (a threaded plug with an attached lifting lug) screwed
into a center tank opening. It is also important that the machine (backhoe, excavator
or crane) used to remove the tank be of sufficient lifting capacity to safely remove
the tank. For example, a small backhoe could be damaged or tipped over while attempting
to remove a large tank.
6. Waste Transportation Requirements
The wastes associated with the permanent closure of UST systems must be transported
as follows:
a. Tank, Piping and Contents
Emptied and Cleaned - An underground storage tank and piping that is emptied
and cleaned on-site is considered scrap metal. If it is to be recycled or reused,
it is not subject to hazardous or residual waste management transportation regulations.
If it is destined for disposal in a landfill, it is subject to the residual waste
transportation requirements (25 Pa. Code §285.218 and §299.201-219).
Emptied but not Cleaned - A petroleum product storage tank containing a substance
that does not fail the test for any characteristic from D001 through D017, which
is empty (contains no more than 1 inch or .3 per cent by weight of its total capacity),
but has not been cleaned, is exempt from the department's hazardous waste transportation
requirements. Residual waste transportation requirements as provided by 25 Pa. Code
§285.218 and §299.201-219 apply.
In the case of a tank which stored a hazardous substance, which meets the definition
of a hazardous waste, or a petroleum product storage tank which contains a substance
that fails the test for any characteristic from D001 through D017, the tank contents
are not subject to regulation as a hazardous waste until the waste exits the tank
in which it was generated, or remains in the tank for a period of more than 90 days
after the tank ceased to be operated as a storage tank ( see 25 Pa. Code § 261.3(e)).
Until 90 days has elapsed, the residual waste transportation requirements apply if
the tank is to be transported, after which hazardous waste transportation regulations
apply.
Not Empty - Any regulated storage tank containing more than 1 inch of residue
(or more than .3 percent by weight of total capacity) may be transported according
to the residual waste regulations for a period of up to 90 days, after which the
hazardous waste regulations apply unless the residue contained in the tank is determined
to be non-hazardous.
The Pennsylvania Department of Transportation (PennDOT) does have two additional
requirements which tend to override DEP`s regulations for transporting tanks that
have not been thoroughly emptied and cleaned. These are:
- If a tank stored a flammable liquid such as gasoline, it must be totally emptied,
cleaned and purged on-site before being transported over the highway. If such a tank
is only "empty" -- one inch of residue remaining -- that "empty"
tank must be transported in a DOT-approved container. Since the transport of an underground
storage tank inside another DOT-approved tank is impractical, the impact of this
requirement is that tanks which contained flammable liquids must be emptied, cleaned
and purged on-site prior to transporting them.
- If a tank stored a combustible liquid (petroleum products other than gasoline),
the tank must be leak tight. This means that the remaining residue cannot leak out
through holes, fittings, etc.
For additional information pertaining to PennDOT requirements, contact PennDOT, Motor
Carrier Enforcement Division, 717-787- 7445.
b. Unusable product, sludges and sediments, tank bottoms and wastewater - These
wastes upon removal from inside the storage tank, if hazardous wastes, must be transported
by a licensed hazardous waste transporter, under manifest. The transporter must ensure
that Chapter 263 is being complied with.
If the wastes are not hazardous wastes, they must be transported in accordance with
Chapters 285.218 and 299.201-219, as residual wastes.
c. Contaminated Soil - Petroleum contaminated soil that is a residual waste must
be transported in accordance with Chapters 285.218 and 299.201-219.
Petroleum contaminated soil that is determined to be hazardous waste and soils contaminated
with products that appear on the hazardous waste lists of commercial chemical products
are subject to regulation as a hazardous waste and must be transported by a licensed
hazardous waste transporter, under manifest. Chapter 263 must be complied with.
d. Recovered or reclaimed product - This is considered a product. Therefore, no licensed
hazardous waste transporter is required. PennDOT regulations, however, apply.
7. Waste Disposal/Treatment Options
a. Empty product tank and piping - Once properly emptied and cleaned, a storage tank
and piping may be recycled. If they are not recycled, these wastes, if hazardous
wastes, must be taken to a permitted reclamation facility or permitted hazardous
waste treatment, storage or disposal facility. If non-hazardous, the wastes can be
disposed of at a facility permitted to accept the wastes.
b. Unusable product, sludges and sediments, tank bottoms and waste-water - These
wastes, if hazardous wastes, must be taken to a permitted reclamation facility or
permitted hazardous waste treatment, storage or disposal facility.
If non-hazardous, the solids can be disposed of at a facility permitted to accept
the wastes. Tank bottoms and wastewater can be treated at a facility which is designated
to treat tank bottoms and wastewater and has an issued NPDES permit and waste management
permit or permit-by-rule which specifies the discharge of treated tank bottoms and
waste-water. The product can be separated and recovered with the remaining wastes
subjected to additional treatment processes prior to discharge.
It also may be possible to discharge non-hazardous liquids to a DEP permitted sanitary
sewer system. However, prior written authorization must be received from the receiving
sewer authority.
c. Contaminated Soil - Contaminated soil shall be used, treated or disposed of in
accordance with department regulation and policy.
Venting or low temperature stripping of contaminated soils may not be conducted without
the express prior consent of DEPís Bureau of Air Quality. In general, such approval
will not be granted with-out the provision of control measures which are subject
to prior review.
Petroleum contaminated soil that is a residual waste may be disposed of at any facility
permitted to accept this type of waste. Other options include, but are not limited
to, low temperature stripping and bioremediation. The department encourages alternatives
to landfill disposal, however, prior review is required.
Petroleum contaminated soil that is determined to be hazardous waste and soils contaminated
with products that appear on the hazardous waste lists of commercial chemical products
are subject to regulation as a hazardous waste and must be taken to a permitted reclamation
facility or permitted hazardous waste treatment, storage or disposal facility.
8. Release Reporting
An owner or operator must notify the appropriate regional office of the depart-ment
as soon as practicable, but no later than two hours, after the confirmation of a
reportable release, in accordance with 25 Pa. Code Chapter 245, Subchapter D, Section
245.305(a)(4), and immediately initiate correc-tive action. See Attachment 1 for
the appropriate release reporting telephone numbers.
In addition, certified installers must report to the department, utilizing the "Notifi-ca-tion
of Contamination" form, a release of regulated substance or confirmed or suspected
contamination from regulated substances observed while performing tank handling activities.
This reporting is required by 25 Pa. Code Chapter 245, Subchapter B, Section 245.132(a)(4)
(relating to standards of performance).
C. Site Assessment
The purpose of a site assessment is to determine if contamination is present around
each storage tank system as a result of any leaks and/or spills which may have occurred
during the operation of the current or any previously existing storage tank system.
It is important to remember that the storage tank system includes all under-ground
piping and ancillary equipment. Subsurface piping should be exposed and the trench
it was laid in carefully examined for signs of obvious contamination wherever access
to the piping is possible. The tank system closure is not complete until a site assessment
has been performed.
A site assessment is not required if:
- A properly installed, calibrated, operated and maintained vapor or ground water
monitoring system is operating as a release detection method up to the time of permanent
closure and the system has given no indication that a release has occurred (The specific
requirements for vapor and ground water monitoring release detection systems are
found at 40 CFR Part 280, Subpart D - Release Detection, Sections 280.43(e) and (f),
respectively); and
- A release does not occur during tank system closure; and
- No obvious contamination is observed during tank system closure.
In certain instances, the owner of an UST system may wish to close only a portion
of the system. This "partial" closure of the UST system is a permanent
closure and requires a site assessment of the portion(s) of the system that is/are
to be closed (e.g. product delivery lines, dispensers, remote fills).
In completing the site assessment for a partial UST system closure, perform the site
assessment for the part(s) of the system being closed according to the following
sections for closure-by-removal or closure-in-place, depending on the option that
is chosen.
Note that closure operations which pull or lift piping out of the ground are considered
closure-in-place for purposes of site assessment as they do not allow a thorough
inspection and visual evaluation of the conditions in the vicinity of the piping.
In cases where the tank is located over a concrete pad, the decision to sample beneath
the pad or at the edges of the pad and the specific locations where to take confirmatory
samples is effected by factors such as the areal extent, condition, and thickness
of the pad, and whether there is any slope or surface irregularities to the pad that
could influence the direction of liquid flow through or off the pad. Because of the
variability of conditions that may be encountered, the regional office should be
contacted for specific requirements when tanks on concrete pads are encountered during
removal or closure-in-place.
1. Tank System Removed from the Ground
(See diagram on page 16)
If the storage tank system is going to be removed from the ground, the site assessment
will be performed during the removal from service activities. Therefore, the person(s)
conducting the site assessment must be present during the excavation of any material
necessary to remove the tank system. The recommended site assessment procedures are
as follows:
a. Excavate Soil/Backfill
Begin by excavating only that amount of soil and backfill material necessary to remove
the tank system from the ground while observing for evidence of obvious contamination.
(Once the tank system is removed from the ground, removal of any soil more than three
feet beyond the tank system in any direction, will be considered as remedial activity
and will not require the use of a certified installer.) Obvious contamination includes,
but is not limited to:
(1) Product stained or product saturated soil or backfill,
(2) Ponded product in the excavation,
(3) Free product or sheen on the water in the excavation.
Obviously contaminated soils must be segregated from soils not suspected to be contaminated
during excavation. This may be accom-plished by visual observation and by field screening
the soils as they are excavated using field instruments such as photoioniza-tion
detectors, flame ionization detectors, portable gas chromatographs and other appropriate
field measurement procedures. The document "Field Measurements: Dependable Data
When You Need It," (EPA/530/UST-90/003) prepared for the U.S. Environmental
Protection Agency, September 1990, describes a number of analytical field procedures.
Segregation of soils during excava-tion will facilitate laboratory testing, treatment
and disposal. Also, excavated soils should be segregated from concrete and asphalt
material. Soils should be stored in accordance with Section VI.B.3, page 9.
If obvious contamination is observed, the owner or operator must proceed as in Section
"b." below. If obvious contamination is not observed, the owner or operator
must proceed as in Section "c".
b. Obvious Contamination
If obvious contamination is observed, the owner or operator must notify the appropriate
regional office of DEP within two hours. See Attach-ment 1 for release reporting
telephone numbers.
If obvious contamination is observed and the obviously contaminated soils are not
segregated from soils not suspected to be contaminated, the excavated soils may not
be placed back in the excavation without treatment and/or testing. If the obviously
contaminated soils are segregated from soils not suspected to be contaminated, the
believed to be "uncontaminated" soil pile must be sampled in accordance
with Section "d.(5)" before being placed back in the excavation or reused
on-site.
(1) Localized Contamination
Localized contamination is defined as contamination that does not extend more than
three feet beyond the tank system in any direction, and does not impact water in
the excavation. In order to check if contamination is localized, proceed with the
excavation of up to three feet of soil extending from the tank system. If, after
excavation, soil and any water in the excavation appear visibly uncontaminated, proceed
with the confirmatory sampling protocol (Section "d"). Submit the closure
report form (Attachment 4) or other report satisfying the requirements of §245.310(b)
within 180 days of reporting the release (see Section VI.F., page 31). Note that
the confirmatory sample locations in section "d" do not apply if the excavation
has extended more than three feet from any part of the tank system being closed.
While it is advisable to leave the excavation open until the sample analysis results
are known, safety considerations may warrant that the excavation be backfilled once
the samples are obtained. In such a case, however, where sample results indicate
unacceptable levels of contamination, additional corrective action will be required.
(2) Extensive Contamination
Extensive contamination is defined as contamination which extends more than three
feet beyond the tank system in any direction, or impacts water in the excavation.
Additional site characterization and corrective action will be required in cases
of extensive contamination. In this circum-stance, the requirements of the corrective
action process regulations must be followed.
Where contamination is extensive, confirmatory samples need not be obtained. However,
it may be desirable to take samples for purposes of beginning the site characterization.
Records of the closure site assessment must be maintained in accordance with Section
VI.F.
c. No Obvious Contamination
If obvious contamination is not observed, proceed with the confirmatory sampling
protocol (Section "d."). Records of the closure site assessment must be
maintained in accordance with Section VI.F.
If obvious contamination is not observed, the soil pile from the excavation does
not have to be sampled if the soil is being reused on-site. However, if the confirmatory
sampling performed in accordance with Section "d." reveals contamination
exceeding the department's statewide standards/action levels, the department may
require sampling of the soil pile.
While it is advisable to leave the excavation open until the sample analysis results
are known, safety considerations may warrant that the excavation be backfilled once
the samples are obtained. In such a case, however, where sample results indicate
unacceptable levels of contamination, additional corrective action will be required.
d. Confirmatory Sampling Protocol/Tank System Removal (See table on page 19)
This sampling protocol applies only where there is no obvious contamination, or where
there is localized contamination. Where extensive contamination has been established,
and a site characterization must be performed, a site-specific sampling protocol
must be developed to determine the magnitude and extent of the contamination.
All confirmatory samples (with the exception of "uncontaminated" soil pile
sampling) must be discrete samples collected in the native soil, one foot below the
product delivery line and two feet below product dispensers, tanks and remote fills.
Where bedrock and backfill interface, samples of the backfill may be collected. Where
water is encountered, both soil and water samples must be collected. Soil samples
are to be taken just above the soil/water interface.
Samples must be collected from all of the following locations for each tank system:
(1) Product Dispensers: one sample below each product dispenser, including dispensers
which distribute multiple products.
(2) Product Delivery Lines: one sample from within the piping trench below the product
delivery line, directly below a swing joint, flex connector or pipe elbow, if one
exists. In cases where there is no swing joint, flex connector or pipe elbow, one
sample must still be taken. The exact location of the sample should be chosen by
the person conducting the site assessment at a location which in their judgment is
most likely to indicate any release of regulated substance. If product delivery lines
to different tanks lie within two feet of each other and carried the same product
(e.g. gasoline), the piping runs may be sampled as if only one product delivery line
was present.
Closure operations which involve pulling or lifting the piping out of an unexposed
or unexcavated trench are to be considered closure-in-place as they do not allow
a thorough inspection and evaluation of the soil conditions in the vicinity of the
piping. See Section VI.C.2.e.(2), page 22.
The location of the sample along the piping run must be shown on the sampling plot
plan. Photographs showing the exposed piping trench should be included with the closure
records.
(3) Tanks:
Where water is not encountered in the tank excavation, soil samples must be collected
as follows:
- For tank capacities up to and including 1,000 gallons, one sample below the bottom
of the tank directly below the fill connection and one sample below the bottom of
the tank directly below the productdelivery line connection. In cases involving the
removal of more than one tank from a single excavation, soil samples are to be collected
for each individual tank.
- For tank capacities of 1,001 up to and including 20,000 gallons, one sample below
the bottom of the tank directly below the fill connection, one sample below the bottom
of the tank directly below the product delivery line connection, and one sample below
the bottom center line of the tank away from the fill and product delivery line connection
sampling locations. In cases involving the removal of more than one tank from a single
excavation, soil samples are to be collected for each individual tank.
- For tank capacities over 20,000 gallons, additional samples may be required.
Contact the appropriate regional office for further guidance.
In cases where more than two feet of soil has been removed from below the tank to
remove localized contamination, take samples from the surface of the bottom of the
excavation as soon as possible following tank removal.
Where water is encountered in the tank excavation, water samples must be collected
in addition to soil samples, as follows:
- For tank capacities up to and including 1,000 gallons, one water sample from
the excavation and one soil sample from each long wall (total of two soil samples)
just above the soil/water interface. In cases involving the removal of more than
one tank (assuming each tank is 1,000 gallons or less in size) from a single excavation,
the excavation may be sampled as if it contained only one tank. For example, if a
single excavation was opened to remove three 1,000 gallon tanks, the sampling requirement
would continue to be one water sample from the excavation and two soil samples, one
from each long wall of the excavation taken just above the soil/water interface.
- For tank capacities of 1,001 up to and including 20,000 gallons, two water samples
from the excavation and one soil sample from each long wall (total of two soil samples)
just above the soil/water interface. In cases involving the removal of more than
one tank (assuming at least one is 1,001 up to and including 20,000 gallons in size),
from a single excavation, the excavation may be sampled as if it contained only one
tank.
- For tank capacities over 20,000 gallons, additional samples may be required.
Contact the appropriate regional office for further guidance.
(4) Remote Fills: if a remote fill is present, one sample below the fill opening.
(5) Soil Pile Sampling: In cases where obvious contamination was observed (either
localized or extensive) and soil was segregated into "presumably contaminated"
and "presumably uncontaminated" piles:
(a) One composite sample per 100 -cubic yards of the "presumably uncontaminated"
soil must be collected and analyzed prior to reuse of the soil on-site. Each composite
sample should consist of four subsamples of the soil pile collected at a minimum
depth of twelve inches into the soil pile.
(b) For up to 100 cubic yards, one discrete sample for each 50 cubic yards or fraction
thereof, of the "presumably contaminated" soil must be collected and analyzed
prior to reuse of the soil on-site. One discrete sample for each additional 100 cubic
yards of soil must also be taken. The samples are to be taken from the most obviously
contaminated areas based upon visual observation and field screening. Sampling may
be conducted prior to or following any treatment. Treatment and disposal options
for contaminated soil are discussed in Section VI.B.7.c., page 13.
It is important to understand that soil which exhibits contaminant levels below the
department`s statewide standards/action levels provided in Attachment 5 is not necessarily
considered "clean fill." This soil, which frequently contains some level
of contamination, can be spread on the site or placed back in the excavation provided
the "standards for reuse of soil on-site" values of Attachment 5 are met.
In addition, there must be no free liquids left in the soil based on visual inspection
and the soil should not create any odor nuisance. If off-site use of the soil
is desired, the owner of the soil should contact the appropriate regional office
waste management staff.
2. Tank System Closed-in-Place or Change-in-Service
(See diagram on page 23)
The department does not recommend closure of tanks in-place. However, there may be
certain instances where structural considerations or access problems prevent tank
system removal. The recommended site assessment procedures are as follows:
a. Physically determine whether water will be encountered in the sampling process
(i.e. between the ground surface and two feet below the bottom elevation of the tank).
b. If water is not encountered, samples must be collected in the native soil, one
foot below the product delivery line and two feet below product dispensers, tanks
and remote fills. Where bedrock and backfill interface, samples of the backfill may
be collected. Samples are to be collected in accordance with Section "e."
below.
c. If water is encountered, both soil and water samples must be collected. Soil samples
are to be taken just above the soil/water interface. Samples are to be collected
in accordance with Section "e." below.
Note: Where water is encountered between the ground surface and bottom elevation
of the tank, sampling through the bottom of the tank should not be conducted. In
this instance, tank sampling should be performed by conducting perimeter soil borings
as in Section "e.(3)(b)" below. Perimeter soil borings are also necessary
when performing a "change-in-service," regardless of water conditions.
d. In the conduct of determining depth to water, performing soil borings or obtaining
soil or water samples, observe the soil or water for evidence of obvious contamination
(i.e. product stained or product saturated soil, sheen or free product in the water
sample).
e. Except where noted, samples must be collected from all of the following locations
for each tank system (Also see table on page 25):
(1) Product Dispensers: one sample below each product dispenser, including dispensers
which distribute multiple products.
(2) Product Delivery Lines:
Where product delivery lines are going to be left in-place, pulled or lifted from
the ground such that the trench they were installed in cannot be thoroughly inspected
and evaluated visually, the lines are to be considered as closed-in-place and the
sampling protocol is as follows:
One sample every 20 linear feet below each product delivery line or portion thereof
(one sample minimum) up to a maximum of five samples for 81-100 feet of piping. Where
the product delivery line is less than 20 feet in length, one sample is still required.
Sampling locations should be evenly spaced. Indicate total length of piping in Section
III of the Closure Report Form. If product delivery lines to different tanks lie
within two feet of each other and carried the same product (e.g., gasoline), the
piping runs may be sampled as if only one product delivery line was present. If an
individual product delivery line consists of more than 100 linear feet or if it is
inaccessible because of a build-ing or some other obstacle, contact the regional
office responsible for the county in which the tank is located for site-specific
guidance.
(3) Tanks:
(a) Where soils under the tank are accessible, samples are to be collected as follows:
- For tank capacities up to and including 1,000 gallons, one sample below the bottom
of the tank directly below the fill connection and one sample below the bottom of
the tank directly below the product delivery line connection.l For tank capacities
of 1,001 up to and including 20,000 gallons, one sample below the bottom of the tank
directly below the fill connection, one sample below the bottom of the tank directly
below the product delivery line connec-tion, and one sample below the bottom center
line of the tank away from the fill and product delivery line connection sampling
locations.
- For tank capacities over 20,000 gallons, additional samples may be required.
Contact the appropriate regional office for further guidance.
(b) Where access to soils under the tank is restricted or where water is encountered
between the ground surface and bottom elevation of the tank, samples are to be collected
by conducting perimeter soil borings. The borings are to be located as close to the
tank as possible, preferably within the backfill, at a distance no greater than five
feet from the perimeter of the tank, as follows:
- For tank capacities up to and including 3,000 gallons, one boring along each
of the four sides of the tank.
- For tank capacities of 3,001 up to and including 20,000 gallons, two borings
along each long wall and one boring along each end wall of the tank.
- For tank capacities over 20,000 gallons, additional borings may be required.
Contact the appropriate regional office for further guidance.
(4) Remote Fills: one sample below the fill opening.
f. If obvious contamination is observed, the owner or operator must notify the appropriate
regional office within two hours. See Attachment 1 for release reporting telephone
numbers. In this circumstance, the require-ments of the corrective action process
regulations must be followed. Site characterization will be required. Confirmatory
samples and laboratory analysis are not necessary to complete the tank closure. Do
not fill the tank with an inert, solid, non-shrinking material, until it has been
determined that it will be unnecessary to remove the tank as part of the corrective
action process. See Section VI.F., page 31, for options on submission and maintenance
of closure site assessment records.
g. If obvious contamination is not observed, all samples collected must be quanti-fied
by a laboratory. Do not fill the tank with an inert, solid, non-shrinking material
until the analytical results are received and it has been determined that corrective
action will not be necessary. See Section VI.F., page 31, for options on submission
and maintenance of closure site assessment records.
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