RE: COMMUNITY WATERSHEDS TERRAIN STABILITY MAPPING FRBC PROJECT # T096198a(TOLKO), VERNON FOREST DISTRICT

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1 Golder Associates Ltd First Avenue Komloops, British Columbia, Canada V2C 6W3 Telephone 1250) Fax 1250) April 17, 1998 Our ref: Tolko Industries Ltd. c/o Kamloops Region Ministry of Forests 515 Columbia S tree! Kamloops, B.C. V2C2T7 ATTENTION: Mr. Tim Giles. P.Geo. RE: COMMUNITY WATERSHEDS TERRAIN STABILITY MAPPING FRBC PROJECT # T096198a(TOLKO), VERNON FOREST DISTRICT Dear Sirs: Please find enclosed a document package relating to I the above-noted project. Could you please forward the documents to the appropriate agencies, including Mr. Kim Young, R.P.F., of Tolko Industries, Lavington Division. Thd attachments include: One set of typed airphotos for the study area. T e terrain mapping is marked directly onto the photos and includes material type, slope range, drainage class, and interpretations for slope stability, erosion potenti:ll and sediment transfer potential. Five copies of the report (four bound copies and 6ne unbound copy). 1:20,000 scale terrain and derivative maps of the broject area (4 sets). One copy of the field cards and notes taken dj ring our field reconnaissance. The information from these forms is summarized in the attached report and on the maps. The originals will be retained by Golder in our project files. one copy of the polygon database (Excel spreadsheet). Should you have any questions or comments regardl g the above information, please do not hesitate to contact us. Yours truly, GOLDER ASSOCIATES LTD. I OFFICES IN AUSTRALIA. CANADA. GERMANY. HUNGARY, ITALY. SWEDEN, UNITED KINGDOM, UNITED STATES

2 I I I Tolko Industries Ltd. Vernon District Terrain Mapping -1- March, INTRODUCTION This report accompanies a set of Terrain Maps IDl:d Derivative Maps produced as a result of detailed terrain stability mapping at terrain :survey intensity level (TSIL) C for 9 community watersheds in the Vernon Forest District. The maps pertain to the following study areas: Irish Creek watershed, (1030 ha) located 17 km northwest of Vernon, BX Group, including BX Creek, Attridge, Klim,i and Dixon watersheds, a 7580 ha cluster of watersheds extending from the municipal boundary to Silverstar Mountain 16 kin northeast of Vernon, Kalamalka Group, including Vernon Creek, Oyama, King Edward Lake, and Kalamalka watersheds (total of 40,020 ha). The locations of the study areas are shown on FigUres 1 and 2, attached. The work was conducted by Golder Associates Ltd. in association with KDW Geographic Solutions Ltd. on behalf of Tolko Industries Ltd. Utvington Division, and funded by FRBC. Terrain mapping and interpretations for slqpe stability, eros ion potential and sediment transfer potential were carried out accor~ing to provincial standards (see Section 2 - Methods). Terrain mapping was carried :out on 1994 series 1: scale colour air photos by a combination of air photo interpretation and field checking. I Original mapped photos and field notes have been retained by the Kamloops Region Ministry of Forests for archiving. This report outlines the mapping methodology followed and criteria developed for slope stability and other interpretations in the project area (Section 2). Comments regarding map reliability and project constraints are also included in Section 2. Section 3 contains a general overview of the study area. Sectiohs 4 and 5 summarize information about surficial materials and processes identified duting the course of mapping. The [mal section contains a brief discussion of the nature and extent of apparent terrain hazards present in the study area. 2.0 METHODS 2.1 Terrain Mapping Terrain mapping followed the standard British Oolumbia procedures for terrain classification (Howes and Kenk, 1997), mapping methods (RIC, 1995) and 5-class stability mapping (Forest Practices Code, 1995). I I Terrain mapping was conducted by Mr. Glen Rutherford, E.I.T. (south half of Kalamalka Group), Ms. Carrie-Lynn Brown, G.I.T. i(north half of Kalamalka Group Golder Associates

3 Tolko Industries Ltd. Vernon District Terrain Mapping -2- March, and final mapping of BX Group) and Ms. Christinl Ouellet, P. Eng. (Irish Creek and pretyping of BX Group), with senior review and. roject management carried out by Mr. Greg Reid, P. Eng. Field checks were perfo med to verify preliminary mapping and, where necessary, revisions to the preliminary I ork. Initial fieldwork was carried out in October 1996 by the three mappers who spent a total of 30 crew days in the various map areas. Supplementary fieldwork was ~equested by the FRBC reviewers as part of the mandatory QA/QC process, which rer,ulted completion of an additional 9 crew days in the summer of 1997 in the BX and IKalamalka project areas. The work involved traversing representative polygons of the "Fious surficial materials and slopes within operable and potentially operable forest areas. In general, road access was adequate in many par~ of all of the project areas, with some exceptions, most notably parts of the Kal1; study area. The map areas were covered in the field by a combination of road quad, and foot traverses, with supplementary visual observations made during a b ief helicopter overflight of parts of the map areas. In general, the traverses were planned to provide representative coverage across all of the map areas while focusing ~n potentially operable regions with steeper slopes and areas of potential instability. Soil pits were dug on occasion where natural exposures, slide scars or tree-throw hollows kere not available for observation t Table 1: Airphotos Project Flight Line Photo numbers Photo Numbers Irish - Nl BCC94051 # Irish - N2 BCC94054 # BX- Nl BCC94048 # I BX-N2 BCC94043 # I BX- N3 BCC94043 # I BX-N4 BCC94048 # I BX- N5 BCC94043 # Kalamalka - N 1 not used I Kalamalka - N2 BCC94052 # Kalamalka - N3 BCC94049 # Kalamalka - N4 BCC94054 # Kalamalka - N5 BCC94089 # I Kalamalka - N6 BCC94099 # I Kalamalka - N7 BCC94052 # I BCC # Kalamalka - N8 BCC94049 # I Kalamalka - N9 BCC94053 # I Kalamalka - N 10 BCC94053 # I Kalamalka - NIl BCC94152 # I Kalamalka - N 12 BCC94058 # I Kalamalka - N 13 BCC94085 # Golder Associates

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