Phase II Environmental Site Assessment (ESA) at Their Tree River C-36 Wellsite and Onsite Sump As Verbally Requested by Indian and Northern Affairs Canada (INAC)
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Environmental Site Assessment Tree River C-36 Gwich’in Region, Northwest Territories May 2011 Prepared for: Chinook Energy Inc. Suite 700, 700 2nd Street S.W. Calgary, Alberta T2P 2W1 MWH File 6930698 MWH Canada, Inc. TEL: 403-543-5353 1010, 600 - 6 Avenue S.W. FAX: 403-233-2513 Calgary, AB T2P 0S5 www.mwhglobal.com EXECUTIVE SUMMARY MWH was commissioned by Chinook Energy Inc. (Chinook) to perform a limited Phase II Environmental Site Assessment (ESA) at their Tree River C-36 wellsite and onsite sump as verbally requested by Indian and Northern Affairs Canada (INAC). The Tree River C-36 wellsite and sump are located within the Gwich‟in Region, Northwest Territories (hereafter referred to as the „Site‟). The objective of this environmental assessment was to assess the condition of the sumps and obtain soil and water samples from the onsite sump location to confirm or refute the potential presence of contaminants of concern (COC) (i.e. salinity impacts) in the soil or water above the applicable guideline values. To achieve the defined objective of this assessment, the following scope of work was undertaken: Obtain surface water samples (both surface water and surface run-off) from the sump cap area and two control areas to be submitted for salinity analysis. Obtain soil samples via hand augering from in and around the sump cap area to determine if any drilling wastes are present or migrating and to determine the thickness of the sump cap. Record the condition of the Site and sump (i.e. vegetation, surficial water flow, condition of sump cap etc.) The submission of soil samples to Exova Laboratories Limited in Edmonton, Alberta for the analyses of potential contaminants of concern (PCOC) (i.e. salinity); and, The preparation of a comprehensive environmental assessment report which includes an assessment of the field data and analytical results in relation to applicable remedial guideline documents. Eight boreholes were advanced using a hand auger to a maximum depth of 0.95m bgl to characterize the onsite sump conditions. The boreholes were used to confirm or refute the present of any environmental impacts from the drilling waste. The findings of the assessment confirmed the following: Soil – Elevated levels of EC, SAR, calcium, magnesium, sodium, chloride and sulphate were reported when compared to the Control values. The Control sample reported a pH exceedance when compared to the applicable guidelines. All other results were reported below the applicable guidelines. Surface water – All of the results were reported comparable to the Control results and below the applicable guideline values. As a result of these findings, there does not appear to be any residual impacts to the surface water from the drilling waste within the onsite sump. Site Condition – Surficial water flow appears to enter the Site from the southwest and crosses through to exit in the northeast. The depth of the sump cap appears to be a minimum of 0.5m thick and remains intact. Vegetation deficiencies were noted on the sump and berm areas. The findings from this investigation indicate that there remain some residual salinity impacts to the soil within the sump area from the drilling waste. The elevated results within the sump area are typical given the nature of the drilling waste. At this time, it appears that the drilling waste is confined to the sump area. Chinook Energy Inc. Page i Environmental Site Assessment Tree River C-36 MWH File 6930698 TABLE OF CONTENTS LIST OF ACRONYMS .................................................................................................................................. 1 1.0 INTRODUCTION .................................................................................................................................. 2 1.1 SITE DESCRIPTION ......................................................................................................................... 2 1.2 ENVIRONMENTAL SETTING .............................................................................................................. 2 1.2.1 Geology ................................................................................................................................... 2 1.2.2 Hydrogeology and Hydrology .................................................................................................. 2 1.3 PREVIOUS ENVIRONMENTAL ASSESSMENTS .................................................................................... 3 1.3.1 Northern EnviroSearch Ltd – Phase I ESA, November 2006 ................................................. 3 1.3.2 MWH - Phase I ESA, April 2010 .............................................................................................. 3 1.4 OBJECTIVE AND SCOPE OF WORK ................................................................................................... 4 2.0 METHOD .............................................................................................................................................. 5 2.1 HEALTH, SAFETY AND GROUND DISTURBANCE ................................................................................ 5 2.2 SOIL SAMPLING .............................................................................................................................. 5 2.3 SURFACE WATER SAMPLING .......................................................................................................... 5 2.4 SITE SURVEY ................................................................................................................................. 6 2.5 QUALITY CONTROL ......................................................................................................................... 6 2.6 LIMITATIONS .................................................................................................................................. 6 3.0 REMEDIAL GUIDELINES .................................................................................................................... 7 3.1 PHYSICAL GROUND CONDITIONS .................................................................................................... 7 3.2 APPLICABLE LAND USE GUIDELINE VALUES - SOIL ........................................................................... 7 3.3 APPLICABLE GUIDELINE VALUES - WATER ....................................................................................... 7 4.0 SOIL RESULTS ................................................................................................................................... 8 5.0 SURFACE WATER RESULTS ............................................................................................................ 9 6.0 SITE CONDITION .............................................................................................................................. 10 7.0 SUMMARY ......................................................................................................................................... 11 8.0 REFERENCES ................................................................................................................................... 13 9.0 DISCLAIMER ..................................................................................................................................... 14 FIGURES FIGURE 1 – SITE LOCATION MAP FIGURE 2 – SITE DIAGRAM AND BOREHOLE LOCATION MAP TABLES TABLE 1 – SUMMARY OF SALINITY ANALYTICAL RESULTS FOR SOIL SAMPLES TABLE 2 – SUMMARY OF SALINITY ANALYTICAL RESULTS FOR SUFACE WATER SAMPLES APPENDICES APPENDIX 1 – SITE PHOTOGRAPHS APPENDIX 2 – BOREHOLE LOGS APPENDIX 3 – SPILL REPORT APPENDIX 4 – LABORATORY CERTIFICATES APPENDIX 5 – SAFETY PACKAGE Chinook Energy Inc. Page ii Environmental Site Assessment Tree River C-36 MWH File 6930698 LIST OF ACRONYMS AEC Area of Environmental Concern APEC Area of Potential Environmental Concern bgl Below ground level BH Borehole CCME Canadian Council for Ministers of the Environment COC Contaminants of Concern CSA Canadian Standards Association EC Electrical Conductivity ESA Environmental Site Assessment GCDWQ Guidelines for Canadian Drinking Water Quality GPS Global Positioning System INAC Indian and Northern Affairs Canada M Metres mg/kg milligrams per kilogram mg/L milligrams per litre mS/cm milliSiemens per centimetre mS/m milliSiemens per metre PCOC Potential Contaminant of Concern ppm part per million QA/QC Quality Assurance/Quality Control SOP Standard Operating Procedure UTM Universal Traverse Mercator Chinook Energy Inc. Page 1 Environmental Site Assessment Tree River C-36 MWH File 6930698 1.0 INTRODUCTION MWH was commissioned by Chinook Energy Inc. (Chinook) to perform a limited Phase II Environmental Site Assessment (ESA) at their Tree River C-36 wellsite and onsite sump as verbally requested by Indian and Northern Affairs Canada (INAC) during the June 14, 2010 meeting. The Tree River C-36 wellsite and sump are located within the Gwich‟in Region, Northwest Territories (hereafter referred to as the „Site‟). Site photographs are presented in Appendix 1. 1.1 Site Description The C-36 wellsite and associated onsite sump are located on Crown land at 67015‟09‟‟N and 131051‟39.4” W (NAD 27). The C-36 well was drilled in January 2003 and subsequently abandoned. The onsite sump is located directly west of well centre. The slopes within the Site boundaries were minimal with a slight slope to the northeast corner. At the time of this assessment, the vegetation onsite comprised of black spruce, pine, natural grasses and muskeg. Land Disposition: Crown Current Site User: Chinook Energy