2009-08-01_HYDROLOGY - M1981112

• Permit No: M1981112
• IBM Index Class Name: Hydrology
• Doc Date: 8/1/2009
• Doc Name: Full Removal & Habitat Restoration & Monitoring Plan
• From: JJ Concrete, LLC & Builders Aggregate Company Properties
• To: DRMS
• Email Name: ECS
• Media Type: D
• Archive: No

Table of Contents

Number / Section Page

1.0 Introduction..........................................................................................................................1
2.0 Existing Physical Conditions..................................................................................................1
2.1 Location & Access .............................................................................................................1
2.2 Property Boundaries & Streets............................................................................................1
2.3 Structures & Equipment .....................................................................................................1
2.4 South Platte River ..............................................................................................................1
2.4.1 Hydrology...................................................................................................................1
2.4.2 FEMA Floodplain ........................................................................................................2
2.4.3 River Channel Function and Processes ........................................................................3
2.5 Wetlands & Waters of the U.S.............................................................................................4
2.6 Upland Vegetation..............................................................................................................4
2.7 Soils...................................................................................................................................5
2.7.1 Bankard Series .............................................................................................................5
2.7.2 Riverwash....................................................................................................................5
2.7.3 Wet Alluvial Land........................................................................................................5
2.8 Mining Operation...............................................................................................................5
2.9 Areas of Unpermitted Fill....................................................................................................6
2.9.1 Left Bank......................................................................................................................6
2.9.2 Right Bank ...................................................................................................................6
3.0 Proposed Physical Conditions ................................................................................................7
3.1 Proposed Remedial Work – Left Bank.................................................................................7
3.1.1 Sandbar .......................................................................................................................7
3.1.2 High Flow Channel......................................................................................................7
3.2 Proposed Remedial Work – Right Bank...............................................................................8
3.2.1 Wetland Fill.................................................................................................................8
3.2.2 Low Water Crossing.....................................................................................................8
3.3 Limits of Construction........................................................................................................8
3.4 Sediment & Erosion Control Structures................................................................................9
3.5 Methods to Minimize Adverse Impacts ..............................................................................9
3.6 Equipment, Access & Fill Removal.....................................................................................9
3.7 Fill Disposal Area ..............................................................................................................9
3.8 Finished Grades & Restored Physical Condition.................................................................9
3.9 Location of Wetlands to Restore.........................................................................................9
4.0 Work Plan & Schedule..........................................................................................................9
4.1 Consult with Corps.............................................................................................................9
4.2 Site Preparation ..................................................................................................................9
4.3 Fill Removal & Final Grades ...............................................................................................9
4.4 Restore Wetlands..............................................................................................................10
4.4.1 Left Bank....................................................................................................................10
4.4.2 Right Bank .................................................................................................................10
4.5 Prepare & Submit As-Built Assessment..............................................................................10
4.6 Prepare & Submit Annual Monitoring Report ....................................................................10
4.7 Rationale for Expecting Success ........................................................................................10
4.7.1 Left Bank....................................................................................................................10
4.6.2 Right Bank.....................................................................................................................11
5.0 Proposed Success Criteria....................................................................................................11
6.0 Maintenance & Monitoring .................................................................................................12
6.1 Maintenance Activities......................................................................................................12