2000-12-11_GENERAL DOCUMENTS - C1981015 (3)

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t Change Orders: Change Order#1: May 26, 2000 1) Additional machine time could be used to further regrade the access road and other locations to approximate original contours. Bond monies were available and the Coal Program approved of the additional reclamation. An estimated 40 hours of track-hoe time (4, $75/hr was directed for an additional $3,000. The item extended the contract 5 days. 2) Additional regrading required additional revegetation work. Approximately 2 acres of additional revegetation was needed. The Additive Alternate #4, Revegetation, amount of $500 was applied. This item extended the contract 1 day. 3) Excessive winds and inclimate weather for revegetation were experienced extending the contract an additional 5 days. The total Change Order costs resulted in an increase to the Purchase Order of$3,500. IV. CONSTRUCTION SUMMARY Construction start-up was delayed because of tardiness in State Purchasing issuing the contract. Prior to issuing the Notice to Proceed, the contractor had already mobilized a Komatsu D41 E dozer to the site and had also installed a locking gate at the start of the access road to the bench to prevent vandalism of the machinery. A Komatsu PC200 track-hoe and a MOXY MT30 Rock truck were mobilized on—site and were used for moving the excavated channel material initially against the trench side cuts and eventually to the designated disposal area to the south. At the later part of slope reduction, material moved to the designated disposal area from the base was performed by the rock truck and a Komatsu WA380 tire loader. The amount of rock encountered during channel excavation was more than sufficient to satisfy the riprap requirements. An excess amount of greater than 4'd rock was encountered. The larger rock was approved for channel placement as long as it was keyed in per specs. Rock placement in the channel was exciting watching the loader dumping rocks at the top of the channel and watching the hoe trying to defend itself from damage. Field Directive #1 was issued shortly after construction commenced. An argument was brought up by the contractor regarding the specifications which referred to two given elevation points and how the slope between them could not be changed from the original/pre-construction grade. Field Directive#1 stated: `There was an oversight on document preparation which neglected to state, in writing, that the channel from the lower point of the gully headcut would be constructed at a 3:1 on Drawing #1 referenced for final grade. The 'construct 3:1 channel from lower(point gully headcut) to bottom of fill slope per specs' referenced 2 given elevation points that exhibited a 2.5:1 and cannot be graded to a 3:1. Therefore the lower point (gully headcut) to bottom of fill slope grade will be at a 2.5:1 per pre-construction". Concern was made by the Coal Program as to the area where the slope would transition between the 3:1 and the 2.5:1. Previous experience has shown how slope transition areas are subjected to higher erodibility from flow velocity and that the transition zone should located higher up-slope as possible. Field Directive #2 authorized additional machine time, Additive Alternate #1 (track-hoe), to be used for additional side channel work from the east and at the toe of the slope. It also directed that machine time could be used to pull out the drainage to the west, to start the access road recontouring, and for sediment pond spillway work. Field Directive #2 also allowed for diviting with the hoe bucket as being an acceptable surface roughening instead of the specified dozer blade furrowing. The punchlist for the channel work included: the need for filling the voids between the larger rock; the need to address side slope riprap placement in places lacking the 48" minimum height; a few side slopes not adhering to the 3:1 specification and; the upper portion checkdam