Personnel or agents of the department may accompany
inspectors on any inspection required by this rule, or inspect settling areas
at any other time which is reasonable under the circumstances involved. They
may also examine any inspection reports and be furnished copies thereof upon
request.
(1) A completed new dam shall
be thoroughly inspected prior to the deposition of industrial wastes above
ground level behind it. Toe drains, spillways and water level control
structures shall be certified by the design engineer as meeting all
specifications of the design, and degree of compaction of the fill shall also
be certified. Legible photographs, either aerial or ground, may be used to
document this initial inspection, but shall not in themselves constitute
certification. A complete file describing the items inspected and their
condition shall be maintained by the owner, and a copy shall be furnished to
the department prior to the above-grade deposition of industrial wastes behind
the dam.
(2) Active dams shall be
inspected weekly unless a defect has been disclosed, in which event the
defective area of the dam shall be inspected daily until corrective maintenance
has cured such defect. Inspections shall be made by employees of the owner of
the dam who have been trained in accordance with subsection
62-672.500(9),
F.A.C. The findings on each inspection shall be recorded, signed by the
inspector, and filed after any necessary corrective action is initiated by
supervisory personnel. The inspector shall travel on foot, horseback, or
wheeled vehicle suitable for traversing the terrain involved at slow speeds.
Dams shall be inspected from the crest and from the toe through the use of
all-weather toe roads or other means of direct inspection from the toe of the
dam. Items to be noted on weekly (or daily) inspections shall include:
(a) Condition of vegetation on dam and in
area for fifty feet (50') downstream from the outside toe.
(b) Piezometric levels within the mass of the
dam when instrumentation has been installed.
(c) Condition of soil surfaces on top and
slopes of the dam and in area for fifty feet (50') downstream from the outside
toe.
(d) Condition of drainage
ditches in the area of the base of the dam.
(e) Liquid surface elevation and amount of
freeboard. (This is to be recorded daily when limitations could be violated
during a week of operations.)
(f)
Condition of spillways and water level control structures, including all
conduits exiting the dams.
(3) Retired dams shall be inspected monthly
by a competent employee of the owner of the dam who has been instructed and
tested by a qualified engineer regarding items to be checked. The findings on
each inspection shall be recorded, signed by the Inspector, and filed after any
necessary corrective action is initiated by supervisory personnel. Such
inspection shall include:
(a) Condition of
soil surfaces on the crest, slopes, and area fifty feet (50') downstream from
the dam.
(b) Determination of
piezometric levels within the mass of the dam while instrumentation of the dam
has been determined to be necessary by an engineer.
(c) Determination of seepage characteristic
through analyses of infra-red aerial photographs or thermal imagery when
surveillance by such means has been proposed by the owner of the dam and
approved by the department.
(d)
Condition of Spillway and water level control structures, including all
conduits exiting the dam, and any wooden structures which are subject to
rotting.
(4) When a
critical condition as listed in subsection
62-672.500(7),
F.A.C., is suspected during a weekly or monthly inspection, the inspector shall
ensure that a technical representative of the dam owner is made aware of the
condition immediately. If the existence of the critical condition is confirmed,
the department shall be notified immediately A written report of the condition
and the actions proposed for its correction shall be made to the department
within seven (7) days from the time existence of the critical condition is
confirmed.
(5) Each active and each
retired dam shall be inspected annually by a third-party engineer who is
experienced in the field of construction and maintenance of dams. Costs for
such inspections shall be borne by owners of the dams. One copy of the report
pertaining to such annual inspections shall be furnished to the department, and
the original of the report shall be retained by the owner. These inspections
shall include:
(a) Analyses of seepage or
other significant items shown on all aerial photographs of the dam which have
been taken for any reason since the date of last annual inspection.
(b) Condition of soil surfaces on top and
slopes of the dam and in areas for fifty feet (50') downstream from the outside
toe.
(c) Review of all weekly,
daily and monthly inspection reports to elevate the effectiveness of
maintenance which was done to the dam during the period since the last annual
inspection.
(d) Examination and
interpretation of data obtained from any instrumentation installed in the mass
of the dam.
(e) Condition of
spillway and water level control structures, including all conduits exiting the
dam and any wooden structures which are subject to rotting.
The annual inspection report shall include recommendations
and corrective measures taken. If corrective measures are not completed by the
time of annual submittal, then follow up inspections shall be conducted by the
third-party engineer with quarterly project reports submitted until completion
of all corrective measures.
(6) A retired dam which is to be abandoned
shall be inspected by an engineer registered in Florida who is competent to
determine that no further impoundment is being accomplished by the dam involved
and that no further surveillance or maintenance is required. A copy of the
final inspection used by the engineer for making his determination as above
shall be furnished to the department, and a copy shall be retained by the owner
of the dam. The department shall be notified prior to abandonment of any dam.
Costs for such terminal inspections shall be borne by the owners of the dams
which are to be abandoned.
(7) Any
of the following items shall be considered as indicating a critical condition
which requires immediate investigation and may require emergency maintenance
action:
(a) Seepage on outer face or
downstream from the toe in which there are boils, sand cones or
deltas.
(b) Silt accumulations,
boils, deltas, or cones in the drainage ditches at dam bases.
(c) Cracking of soil surface on crest or
either face of the dam.
(d) Bulging
of the downstream face of the dam.
(e) Seepage, damp area, or boils in vicinity
of or erosion around a conduit through the dam.
(f) Any subsidence of the crest or
faces.
(8) The following
items shall be considered as indicating potential trouble areas which should be
closely checked on subsequent inspections and repaired as necessary:
(a) Overgrowth patches of vegetation on
downstream face or close area downstream from the toe.
(b) Surface erosion, gullying, or wave
erosion of the upstream face of the dam.
(c) Surface erosion, gullying or damp areas
on the downstream face of the dam, including the berm and the area downstream
from the outside toe.
(d) Erosion
below any conduit exiting the dam.
(e) Wet areas or soggy soil in downstream
face of dam or in natural soil below dam.
(9) The owner of a dam shall provide annual
training to all dam inspection personnel by an engineer experienced in dam
design, construction, operation and inspection, and shall provide training to
all appropriate employees in the implementation of the contingency plan
required by Rule
62-672.550, F.A.C. The owner
shall maintain records documenting such training.
(10) In the event of a dam failure which
permits deleterious substances to enter waters controlled by the State or to
cause other damages, the chairman of the Environmental Regulation Commission
may convene at once a special panel of experts with experience in design and
construction of earthen dams from government, industry, private engineering
firms and/or educational institutions to gather data and to investigate the
cause of the failure and to make recommendations for corrective actions. The
owner of a failed dam shall take immediate action to arrest the flow of
deleterious material when such is possible, and shall have that failed area of
the dam photographed at the earliest practicable time. If feasible, the owner
shall construct a coffer dam upstream from the failed area to impound
materials. This will preserve the area of failure for detailed investigation,
and thus contribute to factual data to be used in future safety
considerations.