WSP03400

• File Number: 8220.200.09.J
• Description: Navajo Project
• State: AZ
• Basin: Colorado Mainstem
• Date: 10/7/1970
• Title: Method of Handling Blowdown Water at Navajo Generating Station
• Water Supply Pro - Doc Type: Report/Study

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salt contained in the station's 3~~year average quantity of blowdown

water of 3,650 acre-feet pe~ year) will approach 29,000 tons under

present conditions, and approach 34,000 tons under future conditions.
The cost of the alternatives for disposing of the blowdown water
from the Navajo Generating Station, described on pages 6-1 and 6-3
of the Bechtel report, were not included in the report but were ob-
tained by phone from Mr. W. V. Coane, Project Manager. The following
table shows cost data for the four least costly alternatives, together
with the incremental cost of each alternative over the cost of the

recommended proposal, its average annual value, and the resulting

unit cost of salt removal. The latter three cost items were derived

from the cost data provided by Mr. Coane.

TABLE I

ESTHlATED COST OF BLO\IDO\lN DISPOSAL

Alternatives for
Disposal of
Blm,dmm Hater

"'~Prcsent.
t'j"or'~:l of
All Cos ts
(ijillions
or $)

Incremental
Cost (p .\-10)
Over Least
Cost Alter-
native (Bil-
lions of $)

Incremental
Annual Cost
Over Least
Cost Alter-
native (Thou-
sands of $)

Increr.1cn tal
Unit Cost or
Sal t R0moval~~i"
($/ton/yr)

~~2 COi~jr,lcad.::: U Pi-O~O;:; cJ.l
Least Cost Alternative

Option IA--Jet Disposal
into Lake Pmrell iL 17

Option 2A--Pretreatment
and Evaporation Pond 13072

Option 3C--Electro-
dialysis 13083

Option 4C--Pretreatment
and Flash Evaporation 14025

5055

396

13020

5.66

404

13050

600G

434

14.50

* Based on a 35-year life for facilities and present worth factor of 14 for
annual costso

** Based on an average of 30,000 tons of salt removed per yearo

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