1998-10-05_REVISION - M1984099 ‎(3)‎

• Permit No: M1984099
• IBM Index Class Name: Revision
• Doc Date: 10/5/1998
• Doc Name: BAILEY PIT 404 PERMIT ADAMS CNTY COLO
• From: ENVIRONMENT INC
• To: TECTONIC CONSTRUCTION CO
• Type & Sequence: TR2
• Media Type: D
• Archive: No

EpviropMelpt' I ]PC,
LARRY E.O'BRIAN 7985 VANCE DRIVE, SUITE 205A
FOUNDER ARVADA,COLORADO 80003
303-423-7297
FAX [phone]
September 17, 1998
Mr. Robert Lowdermilk RECEIVED
Tectonic Construction CO.
P.O. Box 385
Pinecliff, CO 80471 OCT 5
Dear Bob; DIV. OF MINERALS
Ls
GEOLOGY
RE: Bailey Pit - 404 Permit
Adams County Colorado
I have completed the area and volume calculations for the
sloping work you need to do along the St. Vrain River as required
by the Army Corps of Engineers (ACOE) . To do this I used the
measurements we did in July 1998 to create eight cross sections
of the work areas. By using the average height of the bank and
the length, I found calculated the amount of material that would
have to be moved in each section so 3h to lv slopes could be
created. The toe of each slope is 12 inches above the normal
water line in the river. I then used the computer to determine
what would be the best way to excavate a trench along the top of
the existing bank so a cut/fill operation could then easily make
the slopes . I found that if we make the width of the trench
equal to the depth of the slope and the depth one-half the width
the material left would be sufficient to create the 3h to lv
slope. I also said we would use approximately 20 feet along the
top of the slope where equipment would operate.
Each numbered area on the map corresponds to a cross section
and an area number in the tables. Table A shows the calculated
volume of each trench using the numbers from the cross sections
and the length from our measurements . Table B shows the amount
of material left after excavation is done, and available to be
used to create the 3h: ly slope. Table C shows the amount of area
needing reclamation based on the recreated slope length and a 20
ft. wide work area on the tops of the finished slope.
To recap my calculations I found that you would need to
remove a total of 2, 317 cubic yards from 3, 030 feet of river
bank. This will leave 2 , 482 cubic yards available to recreate
the slopes as show on the cross sections . I would suggest you
talk to Hall-Irwin about placing the excavated material on the
setback area by the work area and blend it in with the top of the
lake shore so it does not have to be hauled off for disposal.