WSP03878

• File Number: 8220.106
• Description: Animas-La Plata
• State: CO
• Basin: San Juan/Dolores
• Water Division: 7
• Date: 10/1/1992
• Title: Draft Supplement to the 1980 Final Environmental Statement
• Water Supply Pro - Doc Type: EIS

CONTENTS

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CHAPI'ER II-Proposed Action (continued)
Reclassification or Other Project Lands Refinements. . . . . . . . . . . 11-13
Regulatory Compliance ................................. 11-13
Investigations of Soils Characteristics . . . . . . . . . . . . . . . . . . . 11-13
Additional Compliance With Section 404(r)
of the Clean Water Act ............................ 11-14
Environmental Considerations, Analysis
Assumptions, and Mitigation Measures
Incorporated Into the Proposed Action .................... 11-15

Financial Issues ...................................... 11-15
Phasing of Construction and Cost Sharing ............... 11-15
Tribal Development. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-16
Administration and Maintenance ......................... 11.17

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CHAPI'ER III-Affected Environment and Environmental

Consequences. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 111-1
Introduction ......................................... 111-1
Vegetation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 111.1
1980 Baseline .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 111-1
New or Updated Information. . . . . . . . . . . . . . . . . . . . . . . . .. 111-2
Impacts of 1992 Proposed Action. . . . . . . . . . . . . . . . . . . . . .. III.2

Geology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 111-2
1980 Baseline .............. . . . . . . . . . . . . . . . . . . . . . .. 111-2
New or Updated Information. . . . . . . . . . . . . . . . . . . . . . . . .. 111-4
Impacts of 1992 Proposed Action. . . . . . . . . . . . . . . . . . . . . .. 111-4
Mitigation Refinements. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 111-5

Soils ............................................... 111-5
1980 Baseline .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 111-5
New or Updated Information. . . . . . . . . . . . . . . . . . . . . . . . .. 111.5
Impacts of 1992 Proposed Action. . . . . . . . . . . . . . . . . . . . . .. III-6
Mitigation Refinements. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. III-8

Water Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 111-8
1980 Baseline ..................................... 111.8
New or Updated Information. . . . . . . . . . . . . . . . . . . . . . . . .. III-8
River and Stream Systems ........................ 111-8

Animas River ............................... 111-8
La Plata River .............................. III-9
Mancos River ............................... 111.9
San Juan River. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1II-9
Proposed Project Reservoirs ....................... III.9
Ground Water (Durango Pumping Plant) ............ III-I0
Toxicity Studies for Irrigation Return Flows. . . . . . . . .. III-10
Fish Tissue Sample Results ...................... III-10
Water Sample Results .......................... III-ll
Soil Sample Results ............................ III-ll
Irrigation Return Flow ..... . . . . . . . . . . . . . . . . . . . .. III-ll

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