White Point Landslide Dewatering

Presented by:

Jason Buenker, P.E. July 31, 2013

Target Area

10 Horizontal Drain Alignments

600 ft.

2 Vertical Drain Alignments

Top = Intersect confined zones

Bottom = Relieve potential slide plane

Horizontal Directional Drilling

Drill

Breakout

Pullback

Breakout at the Beach

HDD Breakout

• ~300 gallons discharge

• <1 yd3 sloughing

• Hydrofracture @ 10-15

feet from daylight

White Point Challenges

• Accuracy

• Slope displacement

Installation Accuracy

Microcoil Wireline Location

Microcoil

Grid coil

Slope Displacement

Groundwater Discharge

Success!

Groundwater Post-Dewatering

Drain Flow Rate

(GPM) D-1 - D-2 0.68 C-1 - C-2 - C-3 - C-4 0.04 C-5 0.09 C-6 0.07 B-1 0.53 B-2 0.04 B-3 - B-4 0.14 B-5 0.15 B-6 0.13 A-1 0.01 A-2 0.99 A-3 0.03 A-4 0.04 A-5 0.11 A-6 0.19

Total Flow 3.23 GPM

Boring Head Loss

(ft) B-1 4 B-3 11 B-5 - B-6 3 B-7 13 B-8 2 B-9 16

B-10 10 8 -

B-11 19 27 9

B-12 2 1 6

Avg. Head Loss (East Side)

~ 10 ft.

HDD @ Subsurface Level

Thanks for listening!