FLOOD01986

• County: Bent
• Community: Las Animas
• Stream Name: Arkansas River
• Title: Las Animas Local Protection Project Design Memorandum
• Date: 8/22/1968
• Prepared For: Las Animas
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Project

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e. Concrete aggregate. Drainage structures and other miscellaneous
concrete items will require approximately 1,706 cubic yards of concrete. Due
to the type of structures involved, the abridged Guide Specifications for
concrete (CE 1401.02) will be utilized for this project. Fine and coarse
aggregate (natural sand and gravels) produced by the Fountain Sand and Gravel
Company at Pueblo, Colorado, approximately 85 miles west of the project,
has been approved as a source of concrete aggregate for construction of the
Trinidad Reservoir Project. Test data is shown in TI.1 6-370, volume 1, area
5, latitude 38, longitude 104, index No.5 (suppl) ,Rev ;io, 2). The test
data indicates that the natural sand and gravel aggregates would be satis-
factory for concrete on small civil works projects. Samples of fine and
coarse aggregates (natural sand and gravel) were obtained from the Dent
Builders, Las Animas, Colorado and forwarded to s;m Laboratory for preliminary
elementary physical tests and petrographic analysis. Results of Tests were
reported in SHDED-GL Report !lo. 10350, "Results of Tests of Concrete Aggregate,
Las Animas Levee-Albuquerque District", 11 January 1968, a copy of "hich is
attached as exhibit 3 of Appendix A. Bent Builders obtain coarse aggregate
from the Valley Sand and Gravel Company of Lamar, Colorado and procluce sand
at their Las Animas plant. TIle preliminary elementary phvsical test and
petrographic analysis inJicated that the natural sand and gravel aGgregates
"ould be satisfactory for use on the project. Processing "ill be requirecl
for both fine and coarse aggregates to meet grading requirements as set forth
in the Abridged Guide Specifications for concrete. The above sources will
be shmm as approved sources of concrete aggregate for the project structures.

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f. Protection stone. A total of approximately 366 cubic yarcls
of protection stone will be required at the exite of the various
hydraulic structures. Velocities range from a minimum of J teet per second
to a maximum of 11.1 feet per second and it is anticipated that the flm'/ "ill
be turbulent. A sample for protection stone was obtained from the Turner
Quarry, section 28, T22S, R53H approximately 10 miles NE of Las Animas,
Colorado. The sample "as fon/arded to SHD Laboratory for evaluation. Results
of tests ,"ere reported in S,lDED-GL Report No. 10343 "Results of Tests of
Riprap Material, Local Protection Project, Las Anhlas-Albuquerque District",
28 December 1967, a copy of which is attached as exhibit 4 of Appendix A.
The sample classified as a light gray to buff, moderately sofl to moderately
hard (scratches easily with a brass rod), slightly fossiliferous, slightly
argillaceous, thin bedded limestone. The soundness test indicates the lime-
stone is not quality rock for protection stone; however, the limestone would
be suitable for slope protection providing a thicker than normal layer is
provided. Protection stone, "ell graded from a maximum size of 18 inches
to a minimum size of 6 inches "ill be provided to compensate for poor quality
of rock and an ticipnted turuulance. Layer thicknesses of 18, 24, and 30
inches "ill be provided. Layer thicknesses greater than 18 inches are pro-
vided for aclditional stability in areas of high velocity and turoulance.

g. Bedding material. ^ total of approximately 53 cubic yards of
beddin3 material will be required under the protection qtcne. Eeddin~ materi~l
"lill be natural sand and gr2.vel, processed or ic.ported ~ having the follouin::;

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