2002-02-07_REVISION - M1976020 (7)

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Name [Character] Pure Live Seeds/ Seed Rate Seed/Pound Flz (Pounds PLS/ac) Bluebunch Wheatgrass[native bunchgrass] 125,000 18 6.27 Redtop [naturalized hydrophytio, sodgrass] 4,900,000 14 0.12 Orchardgrass [Raturalized mesic bunchgrass] 600,000 8 0.58 Basin Wildrye [native mesic bunchgrass] 130,000 12 4.02 Meadow Fescue [native hydrophytic sod grass 500,000 20 1.74 Golden Aster [native mesic perennial forb] 400,000 8 0.87 TOTAL 80 13.60 Mulch will not be needed in this area since the reseeding will be covered with an erosion control wood fiber blanket as described below. Item 4 -Use Excelsior Erosion Control Liner to Cover Soiled and Seeded Areas The Excel S-2 Erosion Control Blanket will be used to line the embankment slope from the riprap at the base to the top of embankment. This blanket will be used over the entire 680 feet distance and will be placed as shown on Map C-5. The excelsior blanket consists of weed free Excelsior matrix with a lightweight photodegradeable netting on top and bot- tom. The blanket is sewn together with photodegradeable thread on 2" centers. The aver- age width down the slope that will be needed is 22 feet. From the US Army Corps of En- gineers report of the River, the average velocity during the 100 year flood event is ap- proximately 8 feet per second. Due to the jetty, velocities on the bank will be reduced to approximately 4.5 to 5.0 feet per second or less for this flood. The manufacturers specifi- cation maximum velocity for this blanket is 7.0 feet per second, so [he liner will withstand the 100 year storm even when no vegetation has yet taken hold on the bank. Once the de- signed vegetation has taken hold, the bank will be stronger in resisting the large flood. The species selected above have been chosen for their ability to provide good cover in this area and provide strong root structure to resist erosion during a flood. Thomas Pi[ 2/02 20