DETAILED TERRAIN ST ILITY MAPPING (TSIL C) VUICH C EKAREA

Submitted to

Tolko Industrie Ltd.

Merritt, B..

Terratech Consulting Ltd. F .R. Smith, P. Geo. Salmon Arm, B.C. Project Geologist

Date: 4 April 2002 File: 2001-017 Tolko Industries Ltd. 2 4 April 2002 Vuich Creek - TSIL C File: 200 1-0 17

TABLE OF CONTENf S 1.0 INTRODUCTION ...... 4 1.1 Scope ...... 4 1.2 Report Limitations ...... 4

2.0 PHYSICAL SETTING ...... 5 2. 1 Topography and Climate ...... l...... 5 2.2 Bedrock Geology ...... 1...... 6 2.3 Quaternary Geology ...... , ...... 7

3.0 SURFICIAL MATERIALS ...... 8 3.1 Colluvium (C) ...... 1...... 8 3.2 Fluvial Material (F) ...... 9 G 3.3 Glaciofluvial Materials (F ) ...... 10 3.4 Glaciolacustrine Materials (L G) ...... 10 3.5 Morainal (Till) Materials (M) ...... 10 3.6 Organic Materials (0) ...... j...... 11 3.7 Bedrock (R) ...... 12

4.0 GEOMORPHOLOGICAL PROCESSES ...... 12 4.1 Rapid Mass Movement (-R) ...... 12 4.1.1 Rockfall (-R"b, -Rb) ...... j...... 12 4.1.2 Debris Slides (-R"s, -Rs) ...... 12 4.1.3 Debris Flows (-R"d, -Rd) ...... 1...... 13 4. 1.4 Debris (Soil) Slumps in Sur facial Material (-R"u F"u) ...... 13 4.1.5 Debris Falls (-R"f, Rf) ...... 13 4.2 Gully Erosion (Gullying) (-V) ...... 13 4.3 Seepage (-L) ...... 14 4.4 Avalanche (-A) ...... 14 4.5 Glacial Meltwaters (-E) ...... 14

5.0 METHODS ...... 14 5.1 Pre-Typing Phase: Terrain and Slope ...... 14

;.~ ~:i~d;;:s~ ~.h.a~e.•••••••••••••••••••••••••••••••••••••••• ::.: •• : •• :: .::1:.::.:: .::::: :::: ::::: ::::::: :::: ::: :::::::::::: :::::: :::: ; ~ 5.4 Soil Drainage ...... 16 5.5 Slope Stability (Terrain Stability) ...... 17 ;:~ e~;~~~:~~~:~II;;; ·: :::::::::::::::::::::::::::.::.:.:.:: : :: 1 :::::::::: : ::::::.::::: : :.: :: :: : :::: : ::::::::::::: : :::::.:;~

6.0 RESULTS AND MANAGEMENT IMPLICATION f ...... 23 ~.~ ~~~f~:::i~~t;~~;;~i·:::::::::::::::::::::::::::::::::::::::::: 1 :::::::::::: :: .: : :::::::::::::::::::::::::::::::: : :::: : :: : ;~

7.0 HARVESTING ROAD CONSTRUCTION AND M I NTENANCE SUGGESTIONS ...... 25 7. I General ...... 25

~17 CONSUL T/NG I roo Tolko Industries Ltd. 3 4 April 2002 Vuich Creek - TSIL C File: 2001-017

Figure 1- Study Area ...... (following page) ... 4 Figure 2 - Study Area ...... (following page) ... 6 Figure 3 - Surface Expression ...... 9 Figure 4 - Surface Expression ...... 11

Table 1 - Soil Drainage Classes and Typical Terrain Units and Soils sociated with Each Class ...... 17 Table 2 - Slope (Terrain) Stability Classification (after Ministry ofFo ests, 1999) ...... 18 Table 3 - Preliminary Stability Mapping Classification Derived from andslide Inventory Data ...... 19 Table 4 - Final Terrain Stability classification for the Vuich Creek S y Area ...... 20 Table 5 - Surface Erosion Potential Classes and Typical Terrain Asso iated with Each Class ...... 21 Table 6 - Classification for Surface Erosion Potential Classes ...... 21 Table 7 - Management Implications Associated with Slope Stability C asses ...... 24 Table 8 - Management Implications Associated with Erosion Potentia Classes ...... 25

References ...... 28

Appendix A- Sieve analysis of till from Sutter CreekfI'ulamee River FSR

Map - Vuich Creek Detailed Terrain & Terrain Stability Map

~!J CONSU~nNG UD. Tolko Industries Ltd. 4 4 April 2002 Vuich Creek - TSIL C File: 2001-017

1.0 INTRODUCTION

This report has been prepared as part of a terrain stabili -mapping project for the Vuich Creek Area, which lies within the Merritt Forest District. One :20,000 scale maps of the Vuich Creek area accompany the report. The study area is located in uich Creek, 35 Ian east of Hope and 75 km south of Merritt BC. The study area is located east of the Coquihalla Highway (5), and is 6538 ha. in size comprising part ofTRTh1 sheets 92H035 036, 045 and 046 (see Figure 1). The area is presently being used for forestry, recreational an mining activities. The study area is bounded to the west by the Amberty and Sutter creek wa ersheds, and to the east by the Podunk Creek- River. Tolko Industries Ltd. defined e north and south boundaries for the purposes of the study. Vuich Creek flows through the mi dIe of the study area.

This mapping has been done using standard methods f aerial photographic interpretation and field observations. The study area has been divided into series of polygons with each depicting a relatively homogeneous area of terrain (surficial mate ·als and geomorphological processes), slope (as a range), soil drainage, slope stability and soil e sion potential.

This report is intended to supplement the informatio presented on the terrain stability map. The report describes and reviews the geology and geomorphology of the study area, the characteristics of surficial materials and geomorphol gical processes that are present in the study area; the mapping methodology and map reliabi .ty. Also included is a discussion of management implications.

1.1 Scope

This report and maps have been produced as a po on of the Forest Renewal BC Project Contract #TOM02311/01RKA, entitled, "Anderson, rook and Vuich Creek Watersheds". Terratech Consulting Ltd. undertook this project for Tolk Industries Ltd., Merritt Division.

1.2 Report Limitations

The information presented in this report and on the a companying map is intended for forest development applications only. The slope stability and oil erosion potential are not considered appropriate for other land use applications. The identifi ation and classification of terrain units and the assignment of ratings to derivative variables h been done using the standard methods employed by professional terrain mappers in British Col bia. The level of reliability associated with this mapping is consistent with other Terrain Surv y Intensity Level (TSIL) C studies that rely on aerial photographic interpretation and field obse ations. The interpretations are largely judgmental and heavily based on aerial photographic terpretation. Accordingly, Terratech Consulting Ltd. cannot warrant or guarantee the exactne s of the descriptions and/or boundaries of units shown on the accompanying map. Terratech C suIting Ltd. expects that more detailed assessments will be undertaken for forest operational pI ·ng where warranted.

This report is submitted to the B.C. Ministry f Forests and Tolko Industries Ltd. as information to be used to assist development of forest resources within the defined study area.

~!J CONSUlHNQ I rD. Tolko Industries Ltd. 5 4 April 2002 Vuich Creek - TSIL C File: 2001-017

In order to protect the public, Tolko Industries Lt ., B.C. Ministry of Forests and Terratech Consulting Ltd. from potential misuse of info ation contained within this report or the accompanying maps, authorization for use of, and/or pUblication of, information contained within, or statements regarding, this report or the acco anying map is reserved pending our written approval.

2.0 PHYSICAL SETTING

2.1 Topography and Climate

The Vuich Creek study area is on the eastern edge 0 the Hozameen and Bedded ranges of Cascade Mountain Physiographic Region (Holland, 1 76). The Cascade Mountains are separated by the Fraser River from the Pacific Ranges of e Coast Mountains on the north and are transitional with the Kamloops Plateau to the east. T e Cascade Mountains are composed of Paleozoic and Mesozoic sedimentary and volcanic rock , strongly folded and metamorphosed and intruded by granitic batholiths. The summits of the p aks and ridges attain an approximately uniform elevation, and it is been inferred that the mountai s have resulted from the dissection of a late Tertiary surface. The highest peak in the region is Tulameen Mountain (2285 m), which represents monadnocks1 on an elevated Tertiary erosion urface2 of low relief. The peaks and high ridges are serrate and show the effects of intense alpine glaciation. Cirque basins are noticeable on the north and northeast slopes of peaks and .dges, but at lower elevations there are rounded ridges and dome shaped mountains like Treas re (1729 m). These mountains were overridden by ice at the maximum of the cordilleran ice-s eet. The Tulameen and Vuich valleys were occupied by glaciers and truncated spurs and ice d ed lakes. Since the Pleistocene ice has completely left the .

Vuich Creek flows into Tulameen River, which is p of the Similkameen- system. Vuich Creek begins on the south side of Tul een Mountain (2285 m) and flows a distance of about 6 km to the valley bottom (1260 m) ere it flow through the middle of the study area for about 8 km to its confluence with Tulamee River (1040 m) at the northern tip of the study area. There are three other named watersheds that lie entirely within the Study area. Amberty and Sutter creeks flow east from the height of e Bedded Range near Sutter Mountain (1950 m) around both the north and south sides to Treas e Mountain (1725 m) and into Vuich Creek at (1260 and 1180 m respectively). Chisholm C eek in the southeastern comer of the study area begins at about the 1700 m elevation and flow southward to Podunk Creek at 1290 m elevation (and forms the southwest comer of the study are ).

The study area lies on the eastern boundary of the coa tal mountains and shows a transitional type forest with drier forest types to the east and wetter t es in the west. The Tulameen-Vuich Ridge area is characterizes by the Engelmann spruce biog oclimatic zone, while the Amberty and Sutter Creek areas is characterizes by coastal western h mlock biogeoclimatic zone below the 1500 m elevation with the mountain hemlock biogeoclim tic zone found above this elevation.

I A land surface that has been eroded to a level plain with some small hills having survived -monadnock. 2 A land surface produced by erosion rather than by deposition.

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