5600-PM-BMP0324
2/2012
Module 13: Impoundments
Provide the following information for each impoundment that will be used in operations under this permit. Organize
the information by site and facility.
13.1
13.2
General
a.
Identify the impoundment so that it can be keyed to Exhibit 9.1.
b.
Describe the function of the impoundment.
c.
Attach site-specific cross sections of the impoundment showing: the principal spillway, dewatering pipe,
depth of water, crest of emergency spillway, maximum height of embankment, and existing ground.
Label the cross-section Exhibit 13.1 – Impoundment Cross-Section.
d.
Describe the potential effect of mine subsidence on the impoundment structure.
e.
Provide plans and describe procedures to compute accurate discharge flow rates from sediment and
treatment pond principal spillways and dewatering pipes. The field system as well as the calculation
method must be usable by monitoring personnel and PADEP mine inspectors.
Detailed Design Plan
Include a design report, capacity calculations, construction plans, construction specifications, and
Form 13.2A. If the embankment is more than 20 feet in height as measured from the upstream toe of the
embankment to the crest of the emergency spillway, or has a storage volume of 20 acre feet or more provide
a stability analysis. All plans must be certified by a licensed professional engineer. Impoundments must be
certified by a licensed professional engineer and approved by the Department before being put into service.
13.3
Compliance with 25 Pa Code Chapter 105
Indicate whether or not the impoundment meets the criteria for coverage under Chapter 105 - contributory
drainage area exceeding 100 acres, water depth exceeding 15 feet (measured by the upstream toe of the
dam at maximum storage elevation), or impounding capacity exceeding 50 acre-feet at maximum storage
elevation. Applications for Chapter 105 dams are subject to additional application fees (see Module 1:
Section E, Application Fee).
13.4
13.5
Groundwater Protection
a.
Describe the quality of water that will be contained in the impoundment.
b.
Where impounded water has the potential to cause groundwater contamination or to aggravate an
existing groundwater problem:
i.
Show the liner on the cross section drawings in Module 13.1; and
ii.
Complete Module 14.
Operation and Maintenance Requirements
Describe the operation and maintenance requirements for the structure, including:
a.
Scope and frequency of inspections;
b.
Dewatering of runoff collection ponds following storm events;
c.
Sludge removal operations;
d.
Maintenance of embankments and liners; and
e.
Monitoring.
13 - 1
5600-PM-BMP0324
2/2012
FORM 13.2A: IMPOUNDMENT DESIGN AND CERTIFICATION
Permittee
Permit No.
Pond
Township
County
Engineer/Land Surveyor
Date
Commonwealth of Pennsylvania
Department of Environmental Protection
Bureau of Mining and Reclamation
INSTRUCTIONS
Complete first page and submit with permit application. Use both pages to certify completed impoundment.
Sedimentation ponds and other impoundments must be constructed in accordance with the approved permit before any disturbance of the area to be
drained into the pond. Impoundment must be inspected during construction under the supervision of, and certified to the Department upon completion of
construction by a licensed professional engineer or licensed professional land surveyor.
Any enlargement, reduction in size, reconstruction, or other modification, that may affect the stability or operation must be approved by the Department.
Pond must be certified and approved prior to the start of any other mining activities (see reference sheet – page 13 - 4 of this module).
Unless otherwise specified in your permit, use this form for the sedimentation pond and other impoundment certification. Submit 1 original and 2 copies to
the appropriate District Mining Office. All information must be provided, otherwise it will be returned for completion.
U.S.G.S. Quadrangle:
Location from Bottom Right corner of U.S.G.S.
HYDROLOGY: Drainage Area
Land Use
Soil Type
Location (point of discharge):
Quadrangle:
acres
Design Storm
Latitude
;
inches
Curve Number
North
Longitude
or
inches
West
Average Watershed Slope
Peak Discharge
Permit Application
Embankment
Top Width (Minimum)
Outside Slope (Maximum) (_H: _ V)
Inside Slope (Maximum)
Top Elevation
Bottom Elevation
Upstream Toe Elevation
Downstream Toe Elevation
Amount Allowed for Settlement
Type of Cover
Incised Slope (if any)
Inside Slope (Maximum) (_H: _V)
Top Elevation
Bottom Elevation
Dewatering
Device
Type/Size
Inlet Elevation
Discharge Regulation (i.e., self draining or valve)
Discharge Capacity (cubic feet/second)
Time to Dewater Full Pond
Principal
Spillway
Type
Conduit Diameter (if barrel/riser give both)
Inlet Elevation
Outlet Protection
Spillway Capacity
Emergency
Type
Spillway
Width
Depth (with 2 feet of freeboard)
Length
Side slopes
Crest Elevation
Slope
Type of Lining/Protection
Spillway Capacity (provide design calculations)
Storage
Capacity
Length @ Bottom
Width @ Bottom
Length @ Dewatering Device
Width @ Dewatering Device
Volume @ Dewatering Device
Length @ Crest of Principal Spillway
Width @ Crest of Principal Spillway
Volume @ Crest of Principal Spillway
Length @ Crest of Emergency Spillway
Width @ Crest of Emergency Spillway
Volume @ Crest of Emergency Spillway
13 - 2
As Constructed
5600-PM-BMP0324
2/2012
Permit No.
Pond
Twp./County
Engineer
Date
TO BE COMPLETED AFTER CONSTRUCTION
1. Has the facility been constructed at the location shown in the approved permit?
Yes
No
2. Is emergency spillway constructed in original ground?
And is the type of construction adequate for the required duration and
discharge of the design storm? If “no” checked, explain.
Yes
No
Yes
No
3. Are the collection channels inlets constructed at the proper locations
and located to prevent short-circuiting?
Yes
No
4. Has the pond liner been constructed as outlined in Module 14? (Provide liner
testing documentation)
Yes
No
If not constructed as approved, answer the following questions:
5.
Is the “as constructed” design capable of meeting the performance standards?
If “no” checked, explain.
6.
Identify any conditions or deficiencies in the facility that needs to be corrected.
Yes
No
Construction Inspection
Date of Inspection
Inspected By
Stage of Construction
Supervising Professional Engineer
Address
Telephone Number
I certify that the above-mentioned structure is complete and has been constructed as indicated.
Signature of Professional Engineer/Surveyor
Date
SEAL
Registration Number and Expiration
Date
Signature of Permittee or Responsible Official
Date
Title
13 - 3
N/A
5600-PM-BMP0324
2/2012
Reference Sheet for Form 13.2A
Embankment
Top Width
Original Ground
Inside
Slope
Top Elev.
H
V
Incised Slope
Inside Slope
Incised Slope
Top Elev. &
Upstream Toe
Elev.
H
V
Bottom Elev.
Incised Slope
Bottom Elev.
Slope
H
Outside
Slope
V
Cut-off
Trench
Downstream Toe Elev.
Principal Spillway
(Barrel/Riser)
Principal Spillway
Inlet Elev.
Dewatering
Device Inlet
Elev.
Principal Spillway
(Barrel Only)
Principal Spillway
Inlet Elev.
Principal Spillway
Riser Diameter
Dewatering
Device Inlet
Elev.
Principal Spillway
Conduit Diameter
Principal Spillway
Barrel Diameter
Emergency Spillway
(To be Constructed in Original Ground)
Length
Crest Elev.
Slope
Width
Sideslopes V
V Sideslopes
H
H
Depth + 2’ of
Freeboard
Depth + 2’
of Freeboard
13 - 4
Crest Elev.