GENERAL31411

• Permit No: C1981016
• IBM Index Class Name: General Documents
• Doc Date: 8/4/1994
• Doc Name: INVITATION FOR BID
• Permit Index Doc Type: RECLAMATION PROJECTS
• Media Type: D
• Archive: No

G. East Mine Drainage Reconstruction
Location of the East Mine can be depicted on Exhibit 1B and Exhibit 2C. A rip-rap
diversion ditch has been constructed at the outfall point of culvert #2. The rip-rap
channel extends for a number of feet and ends in the reclaimed portion of the mine.
A channel shall be constructed from the toe of the rip-rap area to the embankment
of the North Fork, roughly 300' in length on a 20% slope. The channel is labeled
ditch #5 and shall be a trapezoidal channel with a bottom width of 3', top width of
10', 1.6' depth and 3:1 sideslopes. Material excavated to create the channel shall be
disposed at the coal waste area located on Map 2A and 2B and handled in
accordance with Task 2.2B.
The ditch shall be lined with a blanket equal to the IANDI.OK TRM 1060 mat.
The blanket shall consist of a lofty web of black polyolefin fibers positioned between
two high strength, biaxially oriented nets and mechanically bound together by pazallel
stitching with polyolefin thread. The three dimensional matrix shall have sufficient
thickness, ground cover and void space to provide immediate erosion protection
while facilitating vegetative establishment. The matrix shall possess strength and
elongation properties to limit stretching in a water saturated condition. Every
component of the matrix shall be stabilized against ultraviolet degradation and inert
to chemicals normally encountered in a natural soil environment. The turf
reinforcement matrix shall also conform to the following physical properties after a
24 hour saturation period.
Property
Thiclmess(in)
Resilienry (%)
Flexibility (]b'in)
Porosity (%)
Ground Cover Factor(%)
Moisture Absorption (%)
Tensile Strength (Ib/ft)
Tensile Elongation (%)
Modulus at 10%
Elongation (lb/ft)
Ultraviolet Stability
Test Method Value
ASTM D-1777 0.5
ASTM D-1777 80
ASTM D-1388 720
Calculated 95
light Projection Analysis 60
ASTM D-570 0.01 (max)
ASTM D-1682 200 • 120
ASTM D-1682 10 (min)
40 (max)
ASTM D-1682 145 ' 110
(tYPi~)
ASTM D-4355) 80
Installation and seeding of the filter blanket shall be in accordance with
manufacture's specifications. The mat shall be keyed in place at the tce of the rip-
rapped area in accordance with manufacture's specifications. Three (3) inches of
topsoil to line the channel prior to mat installation is needed. This material may be
obtained from excess material not used at the sediment pond (if available after slope
and design specification aze met), or hauled in from off site.
The CONTRACTOR shall ensure that all ditches aze maintained and in
configuration which provides adequate runoff control at all times during construction.
Earth materials which collect on the paved road surface shall be removed promptly
it