EROSION AND SEDIMENTATION CONTROL NARRATIVE

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EROSION AND SEDIMENTATION CONTROL NARRATIVE
SR 4026 SECTION 451
SUGAR CAMP RUN DEPARTMENT FORCES BRIDGE
WEST MAHONING TOWNSHIP
INDIANA COUNTY
PENNSYLVANIA
For:
PA Department of Environmental Protection
Southwest Regional Office
400 Waterfront Drive
Pittsburgh, PA 15222-4745
By:
PA Department of Transportation
Engineering District 10-0
2550 Oakland Avenue
P.O. Box 429
Indiana, PA 15701
I.
PROJECT LOCATION AND DESCRIPTION……………………………………3
II.
SOIL TYPES…………………………………………………………………………3
III.
SUGAR CAMP RUN CHARACTERISTICS.……………………………………..4
IV.
EARTHWORKS ACTIVITY AND STABILIZATION.………………………….4
V.
GENERAL DESCRIPTION OF SEDIMENTATION CONTROL………………4
VI.
POST CONSTRUCTION RUNOFF FROM THE PROJECT…………………...5
VII.
LOCATIONS AND TYPES OF PERIMETER AND ON SITE BMPs…………..5
VIII.
SUPPORTING CALCULATIONS…………………………………………………5
IX.
SEQUENCE OF OPERATIONS…………………………………………………...6
X.
MAINTENANCE SCHEDULE FOR E&S POLLUTION CONTROL
MEASURES………………………………………………………………………….7
XI.
RECYCLING OR DISPOSAL OF PROJECT MATERIAL……………………..8
ATTACHMENT A – SITE LOCATION MAPS
ATTACHMENT B – SOILS INFORMATION
ATTACHMENT C – CLEANING OF SEDIMENTATION STRUCTURES
ATTACHMENT D – UNFORESEEN WATER POLLUTION CONTROL
ATTACHMENT E – EROSION AND SEDIMENT CONTROL PLAN AND DETAIL
SHEETS
ATTACHMENT F – EARTHWORK ACTIVITIES AND STABILIZATION BY
SEEDING AND MULCHING
ATTACHMENT G – DRAINAGE AREA MAP AND ROCK PROTECTION
CALCULATIONS
ATTACHMENT H – MEASURES FOR RECYCLING OR DISPOSAL OF PROJECT
MATERIAL
2
E & S Control Plan
SR 4026 Section 451
West Mahoning Township
Indiana County
PROJECT LOCATION AND DESCRIPTION
The Sugar Camp Run Bridge Replacement Project involves replacing a state owned
bridge (SR4026) on township road 860 in West Mahoning Township, Indiana County; at
the intersection of Sugar Camp Road (T-388) and North Point Drive (T-860). See
attachment A for a copy of a section of the USGS Quadrangle topographical map with
the project area outlined along with other site location maps. The purpose of this project
is to provide a safe travel way to convey Township Rd. 860 (State Route 4026) traffic
across Sugar Camp Run. This project will be done by Indiana County PENNDOT
Maintenance forces. The project is scheduled for the summer of 2007.
SOIL TYPES
According to the Soil Survey of Indiana County, Atkins silt loam (At) and Weikert and
Gilpin shaly silt loam, 35 to 100 percent slopes, moderately eroded (WkF2), are the soil
types present at the project location and surrounding areas.
The Atkins silt loam soils are poorly drained alluvial soils that contain some limey
material and have a deep organic surface layer. Typical Atkins soils have a surface layer
of very dark grayish-brown, very mellow silt loam. At about 8 inches depth the soil is
dark grayish-brown silt loam mottled with grayish brown and olive gray. At a depth of
24 to 36 inches the soil is a gray or grayish green silty clay loam. They are moderately
high in fertility and also have a moderately high water holding capacity.
The Weikert and Gilpin shaly silt loam consist of shallow or very shallow, well drained
soils that formed in material weathered from acid shale, siltstone, and fine-grained
sandstone. Shale chips commonly make up about 60 to 80 percent of the dark grayishbrown and friable shaly silt loam surface layer. The subsoil is yellowish brown, friable
very shaly silt loam with low clay content underlain by yellowish-brown shale. These
soils are typically 12 to 24 inches deep and are underlain by olive-brown hard shale or
sandstone.
The District’s environmental unit examined the project and determined there would be no
effect on wetlands. Please refer to Indiana County soils survey sheets for further
information.
(See attachment B)
3
SUGAR CAMP RUN CHARACTERISTICS
Sugar Camp Run is a tributary to Mahoning Creek, which is a tributary to the Allegheny
River. Sugar Camp Run is located in the Middle Allegheny-Redbank watershed which is
part of the Ohio River Basin in Pennsylvania and is classified as a cold water fish stream.
Sugar Camp Run is a non-navigable stream.
EARTHWORK ACTIVITIES AND STABILIZATION
The project will involve excavation for stream diversion, removal of the existing
structure, laying back excavation slopes for workers safety, and the placement of the new
box culvert. Approximately 21,000 square feet will be disturbed. All work will be done
by Department Forces. The excavated material will be placed outside of the flood plain
area or will be used as fill. Stabilization of all areas disturbed by earthwork will occur by
repaving and revegetation. A minimal amount (approximately 50 feet) of paving will be
done on each approach to the structure to match the existing roadway. Seeding and soil
supplements will be used to reclaim all areas disturbed or stripped of its natural plant
cover during the grading operations as per section 804 and 805 of Publication 408 dated
January 2, 2003.
(See attachment F for the Area of Disturbance and Stabilization)
GENERAL DISCRIPTION OF SEDIMENTATION CONTROL
The existing stream will be diverted by a temporary diversion channel, pipe, or pump
with the use of a rock coffer dam or sand bags covered with plastic to contain the stream.
The method of water conveyance will be determined in the field by the project manager.
Any water seeping into the construction area will be pumped into a grassy area not less
than 50 feet from the stream for filtering silt before re-entering the stream.
Accelerated erosion and sedimentation will be decreased through the use of 18-inch silt
barrier fence. Please refer to attached copy of RC-70M for a detail of silt barrier fence.
Sediment collected during the project will be properly disposed of in accordance with
section 861 of the Publication 408 dated January 2, 2003, before beginning the seeding
and mulching process. (See attachment C) Silt fence will be installed along the stream
bank and at the toe of slope along the roadway.
The project engineer is permitted to make modifications in the event of unanticipated
erosion under Unforeseen Project Water Pollution Control per section 845 of the
Publication 408 dated January 2, 2003. (See attachment D).
4
POST CONSTRUCTION RUNOFF FROM PROJECT
Post construction runoff will not be increased over the existing condition, nor will
drainage sheds be altered by the proposed work.
LOCATIONS AND TYPES OF PERIMETER AND ON SITE BMPs
Erosion & Sedimentation Controls for In-Channel and Placement of Precast Box Culvert:
Any in-channel excavation will be done from the top of banks wherever possible. All
excavated material will be removed to a disposal site having an approved erosion and
sedimentation control plan or used as a fill.
The stream will be bypassed by means of a diversion channel, pipe, or pump and a coffer
dam. All bypasses will be completed and stabilized prior to diverting flow.
(See attachment E)
Any pumped water from construction area will be discharged into a well vegetated area a
minimum of 50 feet from the stream and down gradient of the excavation. There will be
an energy dissipater at the discharge end of the pump hose to promote sheet flow across
vegetation. If the discharge area is not well vegetated, a filter bag will be used.
Temporary Control Measures: Standard 18-inch high filter fabric fence, in accordance
with RC-70M, will be used at the toe of the fill slope to control erosion. Rock barrier will
be utilized in the stream to prevent any sediment from washing downstream and to direct
the water flow.
Permanent Control Measures: R-6 rock will be placed in the channel bed at the ends of
the proposed box culvert to prevent scour and erosion. Seeding and mulching will be
completed as per section 804 and 805 of the Publication 408 dated January 2, 2003.
SUPPORTING CALCULATIONS
In accordance with PENNDOT Highway Design Manual Part 2, Publication 13M
September 2000, Chapter 10 – Roadway Drainage Structures, the estimated peak
discharge was determined using the PSU-IV. The drainage area was determined using
USGS Quad Maps and was calculated as 2.75 sq. mi. Also, in accordance with
PENNDOT Design Manual Part 4 Chapter 7, PennDEP E & S Pollution Control Program
Manual, and PENNDOT BD-632M (January 21, 2003) Bridge Design Standards, R-6
rock will be placed at a minimum thickness of 2 feet and at minimum length of 5 feet
from the end of the apron or wing wall for scour protection. (See attachment G)
5
SEQUENCE OF OPERATIONS
1. The existing 18 inch diameter corrugated metal pipe across Sugar Camp Road
T-388 will be removed. The crossing is located at the inlet of the existing
concrete arch culvert. A proposed 18 inch diameter corrugated metal pipe
will be located across T-860 at station 156+88. The proposed pipe will
provide sufficient drainage for T-388 and T-860.
2. A detour will be established and all necessary contacts, such as schools and
emergency representatives, will be notified of the tentative road closure date.
Once the tentative date for the road closure is set, proper signing will be
prepared and all utilities and overhead clearance obstructions will be checked.
3. PennDOT’s survey crew will establish working points for the outside corners
of the toewalls, box, and centerline.
4. Excavation and installation of a temporary stream diversion pipe will be
completed before the existing structure is removed. A rock diversion dam
with plastic lining will be constructed in order to divert the stream into the
pipe. The existing v-ditch, at the outlet end of the diversion pipe, will be lined
with rock. A rock diversion dam with plastic lining will be constructed to
redirect the diverted water further downstream from the bridge.
5. The existing reinforced concrete arch culvert will be removed and the slopes
of the excavation area will be laid back. Any water from the bridge
construction area will be pumped at least 50 feet from the stream. This will
allow the sediment from the pumped water to filter out before re-entering the
stream. There will be an energy dissipater at the discharge of the pump hose
to promote sheet flow across vegetation. If the discharge area is not well
vegetated, a filter bag will be used.
6. The toewalls will be constructed at the working points established by
PennDOT’s survey crew. The toewalls will support the end sections of the
box culvert.
7. PennDOT’s Bridge Maintenance Crew will prepare the box culvert bedding
material from the inlet toewall to the outlet toewall.
8. The box culvert will be placed on the bedding by the vendor with support
from PennDOT. Post tensioning and grouting of the box will be done by the
vendor with support from PennDOT.
9. Waterproofing primer and Royston membrane will be installed on the side
joints of the box culvert sections and along the entire top of the box.
6
10. Backfill will be placed and compacted in lifts. Both sides will be filled and
compacted at the same time.
11. The temporary stream diversion pipe and the rock diversion dams will be
removed. This will allow the water to flow into the existing stream channel.
After the pipe and dams are removed, the pipe trench will be backfilled.
12. The new roadway and approach grades will be paved. Shoulders will be
constructed and approach guiderail will be installed.
13. R-6 rock will be placed in the channel at the box culvert inlet and outlet 2 feet
deep x 5 feet wide along the channel and slopes.
14. Areas disturbed during construction will be seeded and mulched.
MAINTENANCE SCHEDULE FOR E & S POLLUTION CONTROL MEASURES
All erosion and sediment pollution control devices will be inspected weekly and after
each runoff event. Deficiencies found will be repaired immediately. These inspections
will be conducted by a qualified representative of the Department of Transportation.

Silt barrier Fence Maintenance: (18-inch height)
1. Silt fence will be inspected after every precipitation event. Any necessary
repairs will be made immediately.
2. Accumulated sediments will be removed as required to keep the fence
functional. In all cases, remove deposits where accumulations reach ½ the
above ground height of the fence.
3. All the undercutting or erosion of the toe anchor will be repaired
immediately with compacted backfill materials.
4. Adhere to any manufacturer’s recommendations for replacing filter fabric
fence due to weathering.
5. Any section of filter fabric fence, which has been undermined or topped,
must be immediately replaced with a rock filter outlet.
6. Maintain all interim control measures/facilities until all areas protected by
the measures/facilities have reached their permanent structural condition
or 70% uniform perennial vegetative standard.
7. Upon completion of stabilization, all silt barrier fences shall be removed.
7
RECYCLING OR DISPOSAL OF PROJECT MATERIAL
The Department of Transportation will remove all excavated material, pieces of concrete,
and sediment material from the job site. A waste area will be established in accordance
with Publication 408/2006, Section 105.14. Any construction waste may be recycled or
disposed of at an approved site as per Publication 408/2006, Section 105.14.
(See attachment H)
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