GENERAL40807 - Laserfiche WebLink

Home Browse Search

LTC-1 (901) CONTRACTORS ENGINEERS DEVELOPERS ~MORRISON-KNUDSEN COMPANY, INC. E%ECUiWE OFFICE MORRISON~K NUDSEN PLAZA PO BON ]808/BOISE.IDArO U 5 A 80128 !' vRONE 120~13~650001TE1}E% ]68U9 REPLY iO MORRISON~KNUDSEN COMPANY WC PO BOX n2t9 $AN AN fONlO. LE%PSUSA 18211 PHONE ISt 2182a.OC8t April 14, 1986 - _ ./- Mr. D. J. Rose Operations Manager Yampa Mining Company ,~I;i',j (~ ~ ~9~0 P. 0. Box HH Hayden, Colorado 81639 .. Subject: Certification of Outfall 002 - Sanitary LandfillPond Dear Mr. Rose: On April 11, 1986 I performed an inspection of the outfall 002 located at the Sanitary landfill Pond at the Hayden Gulch Mine. I am a registered Pro- fessional Engineer in the State of Colorado and am experienced in the design and supervision of earthen construction. The purpose of my inspection was to certify the structure as required in Rule 4.05.06(7) of the Colorado Mined Land Reclamation Division (CMLRD). As part of my inspection, I have reviewed the permit design documents, surveyed information of the site, and have inspected the structure. I have also discussed the construction of the structure with the engineering staff at the mine. The design elevation of 7579.7 as shown in Volume III of the Permit Appli- cation should be corrected to an elevation of 7543.5. Survey information shows an as-built elevation of 7542.3 for the culvert invert elevation. Survey information of the pond indicates an available storage of 0.63 acre-ft compared to a design capacity of 0.41 acre-ft., thus the structure which will provide additional storage of both water and sediment. The dam is constructed to maintain freeboard as shown in the approved design. The structure named herein has been constructed to a design that approxi- mates that of the original permit application and has improved storage and flood prevention characteristics. The construction of the structure has been accomplished using prudent and proper construction techniques. I hereby certify the structure as meeting the criteria of the CMLRD as defined above and as approved in the current Mine Permit. „ ;E i„ . -~ a~g?ry: Spa -Q a rry .i:#~ed1/57 10 JES:sr stered P. E. No. 17570 ~.......