PHASE 1 EROSION STUDY 2 Recent Erosion and Deposition Processes - - PowerPoint PPT Presentation

PHASE 1 EROSION STUDY 2

Recent Erosion and Deposition Processes Presented By SEAN BENNETT, Ph.D. University at Buffalo Study 2 Leader

West Valley Demonstration Project Quarterly Public Meeting November 15, 2017

• Define the goals of the Study 2 and the tasks

assigned

• Present the methodologies employed and the

results obtained

• Summarize the broader implications

OUTLINE

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TASKS: Quantify environmental parameters that would reduce the predictive uncertainties in future erosion using a landscape evolution model

STUDY 2 -Recent Erosion and Deposition Processes

• Task 2.1b: Digital Mapping of Potential Analogue Sites (Gullies)
• Report completed July 2, 2016
• Task 2.1b: Digital Mapping of Potential Analogue Sites, Amendment 1 –

Expanded Study of 2010 and 2015 LiDAR Data

• Report completed October 18, 2017
• Task 2.2: Quantify Infiltration Capacity
• Task 2.5: Quantify Erodibility of Cohesive Sediment
• Task 2.6: Quantify Erodibility of Clastic Sediment
• Combined report completed March 1, 2017

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TASK 2.1b: Digital Mapping of Potential Analogue Sites (Gullies)

STUDY 2 -Recent Erosion and Deposition Processes

• Objectives: Using the 2010 LiDAR

dataset, (1) define the morphologic characteristics of gullies at the WVDP, and (2) identify analogue gullies nearby using the same data and methodologies

• Methods: Using LiDAR data and

GIS techniques, topographic information from the gullies were determined including slope, length,

• rientation, width, depths, and cross-

sections

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TASK 2.1b: Digital Mapping of Potential Analogue Sites

STUDY 2 -Recent Erosion and Deposition Processes

Gully 1 (NP-1)

Relative Distance (m)

20 40 60 80 100 120 140 160

Elevation (m)

1280 1300 1320 1340 1360 1380

Relative Distance (m)

20 40 60 80 100 120 140 160

Gully Dimension (m)

20 40 60 Width Depth

width: 0.653 depth: 0.489

Gully 1 (NP-1)

Relative Distance (m)

1 10 100 1000

Gully Dimension (m)

1 10 100 Width Depth

width: 0.842 depth: 0.718

Gully 1 (NP-1)

average slope: 0.578 average inner slope: 0.491 Inner Gully Outer Gully Inner Gully Outer Gully Inner Gully Outer Gully

Relative Distance (m)

10 20 30 40 50 60 70

Elevation (m)

1320 1330 1340 1350 1360 1370 1380

Upstream Midstream Downstream

Gully 1 (NP-1)

Typical gully at the WVDP (Gully 1, NP-1)

Plateau Gully Inner Gully Outer Gully Mouth of Inner Gully Outer Gully Drainage Divide Inner Gully Drainage Divide

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TASK 2.1b: Digital Mapping of Potential Analogue Sites (Gullies)

STUDY 2 -Recent Erosion and Deposition Processes

Areas Investigated Gullies 1 and 2 in Area 5, underlain by the Lavery Till, were morphologically similar to the gullies at the WVDP Gully 2, Area 5

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TASK 2.1b: Expanded Study of 2010 and 2015 LiDAR Data

STUDY 2 -Recent Erosion and Deposition Processes

• Objectives: To determine geomorphic changes in topography using

the 2010 and 2015 LiDAR datasets, focusing on: (1) gullies, and (2) bed elevation for selected stream channels

• Methods: Morphologic analysis of gullies on the WVDP (13), and

analogue gullies located within the WNYNSC (Areas 5 and 6)

• Spatially-averaged parameters (length, slope, width, depth)
• At-a-point changes (elevation, width, depth)
• Longitudinal profiles of stream channels: Buttermilk, Franks, Quarry,

Heinz, and Gooseneck Creeks

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TASK 2.1b: Expanded Study of 2010 and 2015 LiDAR Data

STUDY 2 -Recent Erosion and Deposition Processes Results: Similar to values reported in the FEIS (lower advance rates)

• Spatially-averaged rates
• Length: 0.1±2.7%/yr
• Slope: -0.6±1.5%/yr
• Width (near head): 2.9±6.4%/yr
• Depth near head: 2.9±7.9%/yr
• Average rates at-a-point
• Width: 0.028±0.042 m/ha-yr
• Depth: 0.002±0.014 m/ha-yr
• Slope: -0.006±0.012 m/ha-yr

Elevation (m)

390 395 400 405 410 415 420

2010 2015 Width (m)

20 40 60

Relative Distance (m)

20 40 60 80 100 120 140

Depth (m)

5 10 15 20

Gully 1

Relative Distance (m)

20 40 60 80 100 120 140

Difference (m)

• 20
• 10

10 20

Elevation Width Depth Relative Distance (m)

10 20 30 40 50 60

Relative Distance (m)

10 20 30 40 50 60

Midstream Downstream Relative Distance (m)

10 20 30 40 50 60

Elevation (m)

400 405 410 415 420 425 430

2010 2015 Upstream Inner gully Outer gully Inner gully Outer gully

(a) (b) (c) (d) (e) (f) (g)

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STUDY 2 -Recent Erosion and Deposition Processes

• Results: Buttermilk, Franks,

Heinz, and Gooseneck Creeks display a net increase (aggradation) in bed elevation with time (Heinz Creek: 0.003±0.009 m/km2-yr)

• Quarry Creek shows a net

decrease (incision) in bed elevation with time, -0.005±0.009 m/km2-yr

• Changes conditioned by geospatial

uncertainties and hydrologic and geomorphic variability during the study period

Bed Elevation (m)

360 380 400 420

River Kilometer (km)

1 2 3

Change in Bed Elevation (m)

• 2
• 1

1 2

Bed Elevation (m)

360 380 400 420

Franks Creek 2010 Franks Creek 2015

TASK 2.1b: Expanded Study of 2010 and 2015 LiDAR Data

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TASK 2.2: Quantify Infiltration Capacity

STUDY 2 -Recent Erosion and Deposition Processes

• Objectives: Field activities sought

to quantify infiltration rate for selected surficial geological materials (in particular, the Lavery Till) using a double ring infiltrometer

• Methods: A standard double ring

infiltrometer (ASTM D-3385) consisting

• f two steel rings was used
• 37 tests performed in trenches dug in

support of Study 1

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TASK 2.2: Quantify Infiltration Capacity

STUDY 2 -Recent Erosion and Deposition Processes Results: Similar to the values used in the FEIS

• Spatial average:

33±59 mm/hr 20.98±37.8 m3/yr

• Average by elevation (shown)
• Average by frequency (for the

tills): 2±2 mm/hr 1.33±1.37 m3/yr

Infiltration Rate (mm/hr)

0.1 1 10 100

Elevation (ft)

1100 1200 1300 1400

Spatial Average (all data) Average by Elevation Average by Frequency Infiltration Rate (m3/yr)

0.1 1 10 100

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TASK 2.5: Quantify Erodibility of Cohesive Sediment

STUDY 2 -Recent Erosion and Deposition Processes

• Objectives: Field activities sought to quantify the erodibility of

selected surficial geological materials (in particular, the Lavery Till) using the jet erosion test (JET)

• Methods: The JET forces water to impinge the material’s surface

forming a scour hole, and the rate of erosion can be used to estimate the material’s critical shear stress tc and erodibility coefficient kd

• 37 tests performed in trenches dug in support of Study 1

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TASK 2.5: Quantify Erodibility of Cohesive Sediment

STUDY 2 -Recent Erosion and Deposition Processes

• Results: Similar to values used

in the FEIS

• Spatial average:

tc = 42.7±16.4 Pa kd = 2.05±1.75 cm3/N-s

• Average by elevation (shown)
• Average by frequency (for the tills):

tc = 41.7±7.6 Pa kd = 1.76±1.20 cm3/N-s

c (Pa)

20 40 60 80 100

Elevation (ft)

1100 1200 1300 1400

Spatial Average (all data) Average by Elevation Average by Frequency kd (cm3/N-s)

2 4 6

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Scour depth method

TASK 2.6: Quantify Erodibility of Clastic Sediment

STUDY 2 -Recent Erosion and Deposition Processes

• Objectives: Field activities

sought to quantify the surface grain size statistics of selected stream channels near the WVDP

• Methods: Wolman (1954)

pebble count method, and grain size percentiles determined: D10, D16, D50, D84, D90, and D95

• A total of 49 pebble counts

were conducted in and near the WNYNSC along streams as well as Cattaraugus Creek

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STUDY 2 -Recent Erosion and Deposition Processes Results: Similar to values used in the FEIS

• No spatial variation in sediment

texture was observed along streams

• Excluding a few statistical outliers,

grain size data can be aggregated: D10 = 11 mm D16 = 17 mm D50 = 47 mm D84 = 117 mm D90 = 154 mm D95 = 225 mm

TASK 2.6: Quantify Erodibility of Clastic Sediment

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• Analogue gullies can be used for a variety of purposes (site

visits, analysis of landscape evolution, and field-based monitoring programs)

• Observations of gully erosion, infiltration rate, erodibility
• f glacial materials, and stream bed grain size distributions

agree well with previous work and are aligned with those analyses presented in the FEIS (2010)

• These newly collected data will further constrain the input

parameters required to numerically simulate landscape evolution at the WVDP and to reduce the predictive uncertainty of future erosion at the site

Broader Implications

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QUESTIONS?

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