25 Pa. Code § 105.89 - Letters of Amendment and Letters of Authorization for modification of dams and reservoirs
(a)
Projects which do not modify top of dam elevation, normal pool elevation, or
normal operation of the pool level may be authorized by Letter of Amendment
when the dam has an existing permit or by Letter of Authorization when the dam
meets §
105.12(b)
(relating to waiver of permit requirements). The permittee or owner shall
provide the following information:
(1) Reports
and data detailing the conduct and results of investigations and tests
necessary to determine the safety, adequacy and suitability of design,
including:
(i) Data concerning subsoil and
rock foundation conditions.
(ii)
Data concerning exploratory pits, drilling, coring and tests to determine
seepage rates.
(iii) Data
concerning the strength tests necessary to measure the physical properties and
behavior of foundations and embankment materials at the dam or reservoir
site.
(iv) Data concerning the
geology of the dam site or reservoir area, indicating possible hazards such as
faults, weak seams and joints.
(v)
Data concerning availability and quality of construction materials.
(vi) A "Dam Stability Report" as required
under §
105.97 (relating to stability of
structures).
(vii) Other
information as may be necessary to determine the safety, adequacy and
suitability of the design, including the design calculations for the dam, which
shall be made available to the Department on request.
(2) In addition to the site plan and cross
sectional views required under §
105.13(d)(1)(i)
(relating to permit applications-information and fees), construction plans,
specifications and design reports in sufficient detail to evaluate the safety,
adequacy and suitability of the proposed dam, reservoir and appurtenant works,
and a schedule indicating proposed commencement and completion dates for
construction.
(3) For projects
involving storage of fluids or semifluids other than water, information
concerning the chemical content, viscosity and other pertinent physical
characteristics of the fluid or semifluid impounded.
(4) Plans for proposed permanent monitoring
of performance by instrument installations in the dam, including the purposes
of the instrumentation. If no instrumentation is considered necessary, reasons
for this engineering judgment shall be stated.
(5) A hydrologic and hydraulic analysis,
submitted as a separate report, which includes the following:
(i) The size, shape and characteristics of
the drainage basin.
(ii) Current
precipitation data and precipitation distribution information as required by
the Department.
(iii) Streamflow
records.
(iv) Flood flow records
and estimates.
(v) An incremental
dam breach analysis, storage capacity and reservoir surface area for normal
pool and maximum storage elevations.
(vi) Other hydrologic and hydraulic
determinations necessary for the design and operation of the dam.
(6) For an existing dam, copies of
the structure's most recent inspection reports.
(7) An EAP if required under § 105.134
(relating to EAP).
(8) A manual
documenting the operation and maintenance procedures for the dam.
(9) For projects impacting wetlands or
exceptional value waters, or if the project requires 401 water quality
certification, environmental assessment approval will be required under §
105.15 (relating to environmental
assessment).
(b) The
Department may waive the specific information requirements of this section in
writing, if upon review of the request for Letter of Amendment or Letter of
Authorization, the Department finds that specific information is not necessary
to approve the project.
State regulations are updated quarterly; we currently have two versions available. Below is a comparison between our most recent version and the prior quarterly release. More comparison features will be added as we have more versions to compare.
No prior version found.