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Howdy all,
I am bidding a sediment pond retrofit and I am starting to question my
#s. the existing diversion channel is 435' ft long, 170' across and 4' deep at the upper section, and the lower section is 690' x 45' and 4' deep. I am dredging 2 feet of silt out of it, then turning it into 6 sediment traps of various sizes: 90x155, 45x155, 25x155, and 18x40. All sediment traps are 6 ft deep when finished, silt gets disposed of onsite @ 350ft away and the excess material gets used to make the berms between the traps, any extra material gets wasted in the same spot. The lower portion is the same thing except the traps are 640x40 and 40x40 same depth.
My question is time, I figured it at 18 work days to complete using two excavators (Volvo 140, 210) 2 Komatsu CD 60 tracked dump trucks, and 1 Cat D6n. I have already added a contingency cushion for my time, but something is nagging at me.I feel like I am off. Any of you pond gurus think I am way off? I don't wanna loose my ass on this, but I do have to bid it kinda tight. Things are vicious around here.
Thanks for any and all input.
John
I am bidding a sediment pond retrofit and I am starting to question my
#s. the existing diversion channel is 435' ft long, 170' across and 4' deep at the upper section, and the lower section is 690' x 45' and 4' deep. I am dredging 2 feet of silt out of it, then turning it into 6 sediment traps of various sizes: 90x155, 45x155, 25x155, and 18x40. All sediment traps are 6 ft deep when finished, silt gets disposed of onsite @ 350ft away and the excess material gets used to make the berms between the traps, any extra material gets wasted in the same spot. The lower portion is the same thing except the traps are 640x40 and 40x40 same depth.
My question is time, I figured it at 18 work days to complete using two excavators (Volvo 140, 210) 2 Komatsu CD 60 tracked dump trucks, and 1 Cat D6n. I have already added a contingency cushion for my time, but something is nagging at me.I feel like I am off. Any of you pond gurus think I am way off? I don't wanna loose my ass on this, but I do have to bid it kinda tight. Things are vicious around here.
Thanks for any and all input.
John