WSP01249

• File Number: 8220.106
• Description: Animas-La Plata
• State: CO
• Basin: San Juan/Dolores
• Water Division: 7
• Date: 1/1/1990
• Title: Correspondence regarding the Final Biological Opinion - 1991
• Water Supply Pro - Doc Type: Biological Opinion

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fiVe and Cen miles dOwnscream respecCively. The upper SCacion on che Ssn Juan River
was located at tho stateUne near Rosa, New Mexico. The second station was eight
mi les dOI~nst.'eam and the third was eighteen miles below the stateli'ne. A founh
sCation wss set up on the San Juan Rivar 8, fow miles above the dam loca.tion but the
rasults obtained f,X'om the three upper at,1tions were sufficient and this ana wa.s not
used.

The I'otenone concentrations were identica,l fOI' each river. The lippeX' stations
"ere scheduled for cOncentraCions of 2.0 ppm, che second 1.0 ppm, and che chird was
0.5 ppm. Tho stations at the stateline wero opol-atnd for 48 hours. The starCing
times for the lower stations I,'ere delayed to obea,in maximum beneH ts from the rotenone
released by the upstl'eam stations.

Two-man teams traveled the full length of the treatment areas of both rivers
trea.ting the pools and other a,reas not connected l'lith the main river channels.

The rotenone fOl' the NavllJo River wa,s furnished by tho New Mexico Department
of Gamn and Fillh. Jack Dean. Biologist for the U. S. Fish llnd Wildlife Sel'vice wa.s
in charge of this portion of. the projecot. One hundred and twency gallons of rotenone
was applied to the Navajo River from four different drip atations.

For the San Juan River we used 2,280 gallons of. rotenone. At tho sta.tclino
station the rotenone W8," 8,pplied a,t 8, ra,te of 27.5 ge,l1ons pet' hour to supply the
pl,.,.determined eoneentra,tion of 2.0 ppm.

RiVet'.
goHons

The volume of water in the Pine River is much less than thB,t of the Sa,n Juan
Therefore. the volume of rotonone r"qui red W3.S much leaa. ... total of 1,110
for tho three sta,tions.

The two crews working the side pools along the San Juan and l'ine Rivers used
90 gallons of rotenone.

Nine barrels or 270 gallons of rotenone were used to treat a small la.ke cI'eated
during tho construction of the Navajo Dam. '1'hi" lake is separated from the San Juon
River by B, small diko.

A totd of 3,870 ga,llons of rotenone wa,a used for the entire oparetion, all
jobs included.

Tho prolonged treatment (48 hours) wa.s scheduled to insure thorough mixing of
the rotenone through aU sections of the river. Also, for B, sufficient treatment to
insure a good kill of the more resisCant species.

F'i ndings:

Wa,ter temperatures during the rotenone operation va.ri.edfrom B. low of 560 10'.
in tho pinn River and a, high of 670 F. in the San Juan River. Heavy rains prior
co the p.'oject starting time lowered the watel' tempera.ture in both rivers and a. slight
W,Hming trond wss noticed dut'ing the opor8,1'ion.

The size of this project
and weight of ehe fish killed.
all [ish species present. "('his

mado it impossible to determine the tota,l nuolbers
Ho\~eve.', an attempt I~a,s made to collect a, salllp1e of
colloction we,s sent to Dr. William J. Koster of the

F-19-0.4, Job No. C-16-4

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