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iii iiiiiiiiiiiuiii 999 COLORADO MINED LAND FIELD DIRECTIVE RECLAMATION DIVISION 1313 Sherman St., RM 215 Denver, CO 802032273 (303)866-3587 Project name G. E.C. -Orphan Pit- Coal Revocation Project DaM 9/23/93 Contractor name Phil Kessler Btdp RN-GOAL-MINES-$ Contractor addressP 0. Box 41 POM C-70141 Rockvale, CO 81244 R~~PKA-4-0005 Project Manager Erica S. Crosby Fleld Directive 0 -b Use this form to authorize work changes due to changed conditions within the scope of the Purchase Order Contrail. Field directives resuRing in increased Contract price or Completion time must be approved by a formal Change Order within 14 days. The following changes are authorized at the direction of the PROJECT MANAGER: ITEM No. DESCRIPTION OF CHANGES $ Increase/Decrease 2A. liest Pit Pond Cleamut The West Pit pond cleanout descrihed in task 2A of the GEC-0rphan Pit Bond Revoration project is hereby deleted from the smile of work. 3A. Magpie Creek Diversion With the deletion of task 2A, task 3A is herehy niodifietl to the following specifications. Both the Drimary and emergency spillMay culverts from the West Pit pond wail) be removed. The culverts in the undisturbed drainage area Mill alp be removed. The culverts will mt be used for any other smile of work in the bid daument The Magpie Creek embankment by the West Pit pond Mill not be repaired, and will be addressed in task 3C as the ditch outflow point The Magpie Creek emhankment eroded by the undisturbed drainage area Mill be backfilled with fill material from the adjacent area. The embankment shall hlentl in Mith the existing contours in Magpie Creek. 3C. West Pit Diversion The West Pit Diversion task has been deleted and replaced with the following design and spaificetions. The current Nest Pit design Mill join the nativechannel Mith the Mest pit diversion ditch above the current existing Wit pit Pond and outfell into Magpie Creek beloM the pond. There are two transitbn areas that require rip-rap located above the pond in the native channel and the Magpie Creek Diversion. Rip-rap lengths at the too Vansition are 100 feet and 175 fcet at the Magpie Creek transition area The transitan areas should be no steeper than A in grade Mith a minimum 15 fmt bottom width and 2H:1V sideslopes The hrtal channel depth should he 2 feet and the rip- rap thickness should be 1.S feet Rip-rap should be as follows: Dmax = 0.9 feet OSO = 0.15 feet D10 = 025 feet Riprap must be Mell graded, angular in shape, and of excellent durability. The installation must be keyed in at the top and the bottom of the channel. It Mill also be necessary to install a filter layer of approximately 112' m 2" gravel, approximately 10 to 12 inches deep beneath the rip-rap. Rak filter blankets may be replaced with a fabric liner. See drainage stabilization specification in Task 3. Total channel dimensions given above are those dimensions at the rak surface. The rip-rap must be installed over the entire cross section. All junctions must be properly keyed in place 3 feet deep, fora 5 fmt long key length. the channel betMeen the upper and lower junction areas should be 20 feet Mide, minimum sideslopes of 2H:1V with a channel gradient of about 2z. Total depth of the diversion should be 2 feet W~ additional disturbance shall Dour beyond the existing disturhaae in the natural drainage. The existing portbn of the lower diverted natural drainage shall he backfilled with the adjacent stockpiled material and hlentl in Mith the existing topography. All regraded slopes shall be revegetated in aaordance with Task 7. Net change in Contract price Nat change in Contract tlme $ Days This document shall become an amendment to the Contract. All Contract provisions shall apply. Approved by: Date: Project Manager Accepted by: Date: Contractor ,y.,,.....-. ~.qw. nonoyoi uuYl-vm