25291
. Every underground storage tank installed after January 1,
1984, shall meet all of the following requirements:
(a) The underground storage tank shall be designed and constructed
to provide primary and secondary levels of containment of the
hazardous substances stored in it in accordance with the following
performance standards:
(1) Primary containment shall be product-tight and compatible with
the substance stored.
(2) Secondary containment shall be constructed to prevent
structural weakening as a result of contact with any released
hazardous substances, and also shall be capable of storing the
hazardous substances for the maximum anticipated period of time
necessary for the recovery of any released hazardous substance.
(3) In the case of an installation with one primary container, the
secondary containment shall be large enough to contain at least 100
percent of the volume of the primary tank.
(4) In the case of multiple primary tanks, the secondary container
shall be large enough to contain 150 percent of the volume of the
largest primary tank placed in it, or 10 percent of the aggregate
internal volume of all primary tanks, whichever is greater.
(5) If the facility is open to rainfall, then the secondary
containment shall be able to additionally accommodate the maximum
volume of a 24-hour rainfall as determined by a 25-year storm
history.
(6) Single-walled containers do not fulfill the requirement of an
underground storage tank providing both a primary and a secondary
containment. However, an underground storage tank with a primary
container constructed with a double complete shell shall be deemed to
have met the requirements for primary and secondary containment set
forth in this section if all of the following criteria are met:
(A) The outer shell is constructed primarily of nonearthen
materials, including, but not limited to, concrete, steel, and
plastic, which provide structural support and a continuous leak
detection system with alarm is located in the space between the
shells.
(B) The system is capable of detecting the entry of hazardous
substances from the inner container into the space.
(C) The system is capable of detecting water intrusion into the
space from the outer shell.
(7) Underground storage tanks for motor vehicle fuels installed
before January 1, 1997, may be designed and constructed in accordance
with this paragraph in lieu of the requirements of paragraphs (1) to
(6), inclusive, if all of the following conditions exist:
(A) The primary containment construction is of glass fiber
reinforced plastic, cathodically protected steel, or steel clad with
glass fiber reinforced plastic.
(B) Any alternative primary containment is installed in
conjunction with a system that will intercept and direct a leak from
any part of the underground storage tank to a monitoring well to
detect any release of motor vehicle fuels.
(C) The system is designed to provide early leak detection and
response, and to protect the groundwater from releases.
(D) The monitoring is in accordance with the alternative method
identified in paragraph (4) of subdivision (b) of Section 25292. This
subparagraph does not apply to tanks designed, constructed, and
monitored in accordance with paragraph (6).
(E) Pressurized piping systems connected to tanks used for the
storage of motor vehicle fuels and monitored in accordance with
paragraph (4) of subdivision (b) of Section 25292 also meet the
conditions of this subdivision if the tank meets the conditions of
subparagraphs (A) to (D), inclusive. However, any pipe connected to
an underground storage tank installed after July 1, 1987, shall be
equipped with secondary containment that complies with paragraphs (1)
to (6), inclusive.
(b) The underground tank system shall be designed and constructed
with a monitoring system capable of detecting the entry of the
hazardous substance stored in the primary containment into the
secondary containment.
(c) The underground storage tank shall be provided with equipment
to prevent spills and overflows from the primary tank.
(d) If different substances are stored in the same tank and in
combination may cause a fire or explosion, or the production of
flammable, toxic, or poisonous gas, or the deterioration of a primary
or secondary container, those substances shall be separated in both
the primary and secondary containment to avoid potential intermixing.
(e) If water could enter into the secondary containment by
precipitation or infiltration, the facility shall contain a means of
monitoring for water intrusion and for removing the water by the
owner or operator. This removal system shall also prevent
uncontrolled removal of this water and provide for a means of
analyzing the removed water for hazardous substance contamination and
a means of disposing of the water, if so contaminated, at an
authorized disposal facility.
(f) Underground pressurized piping that conveys a hazardous
substance shall be equipped with an automatic line leak detector and
shall be tightness tested annually.
(g) Before the underground storage tank is covered, enclosed, or
placed in use, the standard installation testing for requirements for
underground storage systems specified in Section 2-7 of the
Flammable and Combustible Liquids Code, adopted by the National Fire
Protection Association, (NFPA 30) as amended and published in the
respective edition of the Uniform Fire Code, shall be followed.
(h) Before the underground storage tank is placed in service, the
underground tank system shall be tested in operating condition using
a tank integrity test.
(i) If the underground storage tank is designed to maintain a
water level in the secondary containment, the tank shall be equipped
with a safe method of removing any excess water to a holding facility
and the owner or operator shall inspect the holding facility monthly
for the presence of excess water overflow. If excess water is
present in the holding facility, the permitholder shall provide a
means to analyze the water for hazardous substance contamination and
a means to dispose of the water, if so contaminated, at an authorized
disposal facility.