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pipeline ROW restoration
- Thread starter jlockard
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LittleInch
Petroleum
Waste factor?
Hydroseeding?
Care to explain a bit more? Never heard of that terminology before.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
Hydroseeding?
Care to explain a bit more? Never heard of that terminology before.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
- Thread starter
- #3
Sure. Waste factor is how much of the material will be wasted during application or transport. For example, hydroseeding, if using a spray method, will have bad seed or overspray or birds eat it or whatever. So I'm seeing a 20% estimate from one of my contractors. Aggregate, lets say you've got an 8 yard truck, some of it will fall off the truck, some of it will roll down the hill, etc. So you need 8 yards but factor how much more should you estimate to make sure you've got it covered. 10%? 20%? Another example is you get a truck full of fill material, but some of that could be rock or other unsuitable material you can't use that's wasted because it can't go back in the hole. Think of it another way, you're carrying a bucket of water up a rocky hill, some of that water will spill, so it's wasted. How do you estimate how much of that will be?
Cant say I've ever really thought about seed overage. Never even seen it as a bid line item. Probably depends some on the size of the job.
5% allowance for welding rods for a "typical" pipeline system, but for a simple tie-over and meter station, that might be 15%.
Judging by what I've seen, some areas simply get a less dense coverage as supply runs down.
What do your other contractors say? Throw out the high and low and average what's left.
--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
5% allowance for welding rods for a "typical" pipeline system, but for a simple tie-over and meter station, that might be 15%.
Judging by what I've seen, some areas simply get a less dense coverage as supply runs down.
What do your other contractors say? Throw out the high and low and average what's left.
--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
LittleInch
Petroleum
Does it matter?
Seeds I haven't a clue, but 20% sounds a bit high - depends on what preparation or post treatment is done I reckon.
Spraying seeds out in water leaves more to be eaten or not germinate so maybe 20% is good, but how will you ever know? Going to count individual seedlings? Don't think so.
For fill I would think no more than 5%.
The authorities don't like wagons tipping soil etc all over the roads and a good contractor won't let it run away.
Ditto if your backfill contains lots of rocks etc then run it through a crusher first.
Or buy it from a reputable source, not someone with a truck who offers you "fill" and then goes round the corner and digs up some waste ground...
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
Seeds I haven't a clue, but 20% sounds a bit high - depends on what preparation or post treatment is done I reckon.
Spraying seeds out in water leaves more to be eaten or not germinate so maybe 20% is good, but how will you ever know? Going to count individual seedlings? Don't think so.
For fill I would think no more than 5%.
The authorities don't like wagons tipping soil etc all over the roads and a good contractor won't let it run away.
Ditto if your backfill contains lots of rocks etc then run it through a crusher first.
Or buy it from a reputable source, not someone with a truck who offers you "fill" and then goes round the corner and digs up some waste ground...
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
- Thread starter
- #6
Generally no it doesn't matter. That's valid. However in this case I'm trying to validate, or at least give some credibility or lack thereof, to a contractor estimate. Doing restoration in very steep mountains where they're running their own crushers and spillage is very commonplace. They actually listed a waste factor on their estimate workup and I'd never seen one actually have the cojones to do that in all my years, so I was curious if anyone else had ever considered it or come across it. I'll give em credit for being open about it. Seeding I can see overspray and a dozen other reasons to say 15-20% would be not unreasonable. A touch high maybe but wouldn't really argue with it. Aggregate, however, these clowns actually listed 50% which in my mind was insanity but maybe others had seen similar so thought I'd throw it out there and see if maybe I was the looney.
LittleInch
Petroleum
"aggregate" to me is decent sized stones and gravel which you add to sand and cement to make concrete.
But 50% sounds ridiculously wasteful.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
But 50% sounds ridiculously wasteful.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
What specifically is the aggregate needed for? It should be possible to determine how much is required within +/- 20%, if not 10.
Hauling around rocks and dirt is not particularly desirable.
Small rocks can be used as backfill in the trench, if necessary, but again not desirable, and the excavated material would normally be deemed unsuitable in order to make it necessary. I'd tell him to sharpen his pencil on that 50% number, or just flat out tell him there's no way you'll accept anything over 15% without justification on exactly why he cannot calculate the volume. Is it a karst geology with potential sinkholes to be uncovered or something. If that's true, tell him you will accept the exact volume needed to fill any voids discovered as an extra payment item. Agree on that price per yd3 in place now.
--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
Hauling around rocks and dirt is not particularly desirable.
Small rocks can be used as backfill in the trench, if necessary, but again not desirable, and the excavated material would normally be deemed unsuitable in order to make it necessary. I'd tell him to sharpen his pencil on that 50% number, or just flat out tell him there's no way you'll accept anything over 15% without justification on exactly why he cannot calculate the volume. Is it a karst geology with potential sinkholes to be uncovered or something. If that's true, tell him you will accept the exact volume needed to fill any voids discovered as an extra payment item. Agree on that price per yd3 in place now.
--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
- Thread starter
- #9
It's for restoration of a Right of Way so ditch backfill and final grade is complete. They're restoring the ROW to original grade so hauling in native material to replace. I agree with you both that 50% is simply unacceptable, nor is it justifiable. It's simply an excuse to balloon their costs and I've rejected the estimate outright with instructions to come back with a real number or not at all. Appreciate the input here. Also told them we'd be doing lidar scans afterwards so I wanted a unit rate and wouldn't grant a penny over actual scan results.
Never seen a published value because... It depends on the means and methods. 20% is comical. I'd reject it and ask why they are allowing that much to go to waste. If they are, that isn't your problem. 5% is probably right, so you should be willing to expect to accept 10%.
In the future take this out of your bid packages. They get paid for what you get. If they spill some along the way, why should that be your problem.
In the future take this out of your bid packages. They get paid for what you get. If they spill some along the way, why should that be your problem.
In the case of grass, it might be the amount of seed that does not germinate.
But that reasoning doesn't work for aggregate.
--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
But that reasoning doesn't work for aggregate.
--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."
I think the OP should make an important distinction with their contractor.
Things that got get wasted because it is bad (aka not to spec, the wrong size for rock, spills out of the truck, whatever) is not their problem. If seed and/or aggregate is correctly installed and then is later damaged (by birds eating it, huge rainstorm OVER THE DESIGN STORM, washing it out, etc) would be the responsibility of the owner (not contractor) to "buy again".
As far as seeding, generally - here in the eastern United States, we typically have mass seeding events after completion of construction. If this is done correctly with the right seed mixes and such, you normally get substantial coverage quickly. Most projects do require one or two areas to be reseeded.
My advice would be to generally not entertain the idea of someone getting paid a "waste factor" but allow them to add quantities when things must be redone for issues that aren't their fault.
Things that got get wasted because it is bad (aka not to spec, the wrong size for rock, spills out of the truck, whatever) is not their problem. If seed and/or aggregate is correctly installed and then is later damaged (by birds eating it, huge rainstorm OVER THE DESIGN STORM, washing it out, etc) would be the responsibility of the owner (not contractor) to "buy again".
As far as seeding, generally - here in the eastern United States, we typically have mass seeding events after completion of construction. If this is done correctly with the right seed mixes and such, you normally get substantial coverage quickly. Most projects do require one or two areas to be reseeded.
My advice would be to generally not entertain the idea of someone getting paid a "waste factor" but allow them to add quantities when things must be redone for issues that aren't their fault.
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