Appendix 9A Hydrogeological Baseline Report

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Proposed HR Milner Expansion Project Environmental Impact Assessment Report Appendix 9A: Hydrogeological Baseline Report

Maxim Power Corp. Page 9A-1 January 2009 REPORT TO

MAXIM POWER CORPORATION and ALBERTA ENVIRONMENT

HYDROGEOLOGICAL BASELINE REPORT, HR MILNER GENERATING STATION, NEAR GRANDE CACHE, ALBERTA

PROJECT NO.: PR08-04

Prepared By

July 28, 2008 Executive Summary

Maxim Power Corporation (MAXIM) is currently in the process of a major expansion of their existing HR Milner thermal power generating station located approximately 20km north east of Grande Cache, Alberta. The HR Milner Generating Station and facilities are located in the north half of Section 10 and the south half of Section 15, Township 58, Ranges 7 and 8, West of the 6th Meridian. The expansion will require a number of initiatives including the development of both a baseline environmental assessment and an environmental impact assessment. This section provides the hydrogeological information requested in Section 4.3.1 of Alberta Environment’s (AENV) April 8, 2008 Draft Terms of Reference. Impact assessment and monitoring/mitigation components are provided in Section 9 of the Impact Assessment Report.

The HR Milner Generating Station is located on a flood plain terrace on the northwest bank of the Smoky River immediately down-gradient from the Grande Cache Coal Corporation’s Coal Processing Plant. The terrace that underlies the Station is approximately five metres above river elevation. Surface drainage is toward the Smoky River; however, most rainfall infiltrates vertically downward into the underlying groundwater unless collected in storm drains and ditches.

Potential sources of impact to local groundwater at the existing and proposed Plant Site include: • holding tanks and water line leaks on the process system (including fire suppression system), waterworks or domestic wastewater systems, • discharge of process water blowdown to the settling ponds, • chemical/fuel spillage, and • treatment chemicals (water softening primarily) in process water discharged through the settling ponds.

The uplands area surrounding the Station consist of front range mountains formed by the Cretaceous Luscar Group. Adjacent bedrock outcrops in the lower portion of Smoky River Valley consist of the underlying Torrens Member, Moosebar Formation and the Gladstone Formation.

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throughout much of the Smoky River valley during deglaciation. This formation has been locally incised and eroded by intermittent streams cascading down the slopes of uplands on both sides of the river.

The Station is located on a point bar deposit laid down as a Quaternary alluvial deposit from the Smoky River which is a braided stream in a confined valley. Recent groundwater exploration at the GCC Plant Site has shown coarse gravel deposit is present immediately overlying the bedrock in this area and is interpreted to be preglacial in origin.

The shallow alluvial sand and gravel aquifer underlying the Station contains coarse sand, gravel and cobbles. The shallow aquifer unconfined and is within ten metres of ground surface and is hydraulically linked with water levels in the Smoky River. The deep gravel aquifer intersected by groundwater supply boreholes at GCC is a limestone/dolomite coarse gravel/cobble deposit likely forming confined basal aquifer overlying bedrock at an average elevation of 865masl. Given the much higher content of limestone in the gravels, it is interpreted to be a pre-glacial alluvial valley deposit as the closest limestone deposits are over 20km upstream in the Smoky River Valley.

The orientation of shallow groundwater movement in the river valley is seasonally variable. Typically, groundwater moves down gradient toward the Smoky River during most of the year when the Smoky River is at low or mean flow with reversed recharge from the river occurring within during brief high river flows in May or June. The deep gravel aquifer is recharged from the Smoky River at some point upgradient but can be no closer than 700m from the Station and possibly as much as five kilometres upstream.

Hydraulic conductivity (K) testing carried out in 2001 found that the alluvial aquifer yielded mean K values in the order of 7 X 10-6 m/s (0.6m/day). Hydraulic gradient (ί) is variable depending upon groundwater and river water elevation. Monthly groundwater gradient from the GCC plant site to the Smoky River was calculated based on the relative water levels from monitor wells to the river from 2004 to 2007. Hydraulic gradients over the Plant Site and have been found to range from +0.011 (late winter to the river) and -0.022 (from the Smoky River to groundwater for a few weeks in early June 2006). Groundwater movement is generally parallel with the Smoky River throughout most of the year. Recharge of groundwater from the Smoky occurs for only a few weeks during the spring freshet and does not extend more than 50m from the river itself.

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Recent testing indicates this aquifer has a relatively high transmissivity in the range of 300 to 500m2 per day. With a maximum aquifer thickness of ten metres, this equates to a hydraulic conductivity in excess of 30m/day which is much higher than the shallow aquifer. Potential developable long term yields in excess of 1000m3/day may be possible.

There is an excellent groundwater monitoring network and baseline database available which from the existing HR Milner and GCC monitoring networks. There are three groupings of water quality type based on source and location:

• Smoky River Water typically of the calcium bicarbonate type (Upper Smoky River), • The shallow alluvial aquifer typically of the calcium bicarbonate type with increasing sodium content, and • The deeper preglacial gravel aquifer containing softer water with increased proportion of sodium and chloride.

It is evident that water quality becomes increasing mineralized with depth and distance from the Smoky River. The cation exchange mechanism is evident and typical of increasing travel and residence time.

With the common exception of manganese and TDS, all groundwater samples collected from the existing HR Milner Station groundwater monitoring wells in 2006 met the applicable guidelines (Canadian Drinking Water Quality Guidelines [CDWQG]). All trace elements, with the exception of manganese and occasionally dissolved iron, met the CDWQG.

The existing Milner Generating Station does not utilize groundwater as domestic water is hauled by truck from Grande Cache. The nearby GCC plant site uses a licensed 35m industrial water supply well for potable water use. The nearest domestic users are located approximately four kilometres downstream at Wanyandie Flats where at least two water supply wells are used as a manual community supply.

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TABLE OF CONTENTS

EXECUTIVE SUMMARY...... 1 TABLE OF CONTENTS...... 4 1.0 INTRODUCTION AND SCOPE ...... 6 2.0 TOPOGRAPHY, DRAINAGE AND SITE OPERATIONS ...... 6 2.1 Topography ...... 6 2.2 Surface Runoff and Storm Drainage ...... 7 2.3 Wastewater Drainage and Control ...... 7 2.4 Generating Station Operations ...... 8 3.0 GEOLOGY ...... 8 3.1 Bedrock Geology ...... 8 3.2 Surficial Geology ...... 9 4.0 HYDROGEOLOGY ...... 9 4.1 Bedrock Aquifers ...... 10 4.2 Surficial Aquifers ...... 11 4.2.1 Shallow Gravel Aquifer ...... 11 4.2.3 Deep Gravel Aquifer ...... 11 4.3 Groundwater Movement ...... 12 4.3.1 Shallow Gravel Aquifer ...... 12 4.3.2 Deep Gravel Aquifer ...... 12 4.4 Groundwater Users ...... 12 4.5 Quantitative Hydrogeology ...... 13 4.5.1 Shallow Gravel Aquifer ...... 13 4.5.2 Deep Gravel Aquifer ...... 14 5.0 WATER QUALITY ...... 14 5.1 General Water Quality Observations ...... 14 5.2 Groundwater Quality Trend Analysis...... 16 5.2.1 Chloride ...... 16 5.2.2 Sodium ...... 16 5.2.3 Sulphate ...... 17 5.2.4 Total Dissolved Solids (TDS) ...... 18 5.3 Water Quality Discussion ...... 19 6.0 CONCLUSIONS ...... 20 7.0 CLOSURE ...... 23

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LIST OF APPENDICES

Appendix 1: Figures and Cross-Sections

Figure 1: Regional Setting Figure 2: Plant Site Area Figure 3: Stratigraphic Column Figure 4: Regional Geology Figure 5: Bedrock Geological Cross-Section A-A’ Figure 6: Surficial Geology Section C-C’ Figure 7: Regional Hydrogeology Figure 8: Other Groundwater Users Figure 9: Local Shallow Groundwater Movement October, 2006 Figure 10: Groundwater Quality (Piper Plot)

Appendix 2: Monitoring Wells and Waterwell Logs Appendix 3: Analytical Database Laboratory Analytical Reports

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1.0 INTRODUCTION AND SCOPE

The expansion will require a number of initiatives including the development of both a baseline environmental assessment and an environmental impact assessment. This section provides the hydrogeological information requested in Section 4.3.1 of Alberta Environment’s (AENV) April 8, 2008 Draft Terms of Reference. Impact assessment and monitoring/mitigation components are provided in Section 9 of the Impact Assessment Report.

The report makes substantial use of information developed and utilized by Grande Cache Coal Corporation (GCC) who occupies the lands immediately adjacent to the Generating Station. GCC have conducted significant exploration and monitoring in the area surrounding their property in support of their initial 2001 Application and in Annual Monitoring Reports since 20041. This information is augmented by over 12 years of annual groundwater monitoring data collected by operations staff at the HR Milner Generating Station2. As a result of the available data set and access to this data (as agreed by GCC), no new hydrogeological explorations or investigations were carried out.

2.0 TOPOGRAPHY, DRAINAGE AND SITE OPERATIONS

2.1 Topography

The HR Milner Generating Station (Station) is located on the northwest bank of the Smoky River immediately down-gradient from the Grande Cache Coal Corporation’s Coal Processing Plant (Figure 2, Appendix 1). The Station is located on a flood plain

1 Annual Groundwater Monitoring Reports; Annual Reports submitted to AENV by Grande Cache Coal Corporation; 2004-2007 2 Annual Groundwater Monitoring Reports; Annual Reports submitted to AENV by Milner Power Corporation; 1991-2006

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terrace on the north side of the Smoky River (Figure 2). The terrace that underlies the Station is approximately five metres above river elevation.

2.2 Surface Runoff and Storm Drainage

Surface drainage is toward the Smoky River; however, most rainfall infiltrates vertically downward into the underlying groundwater unless collected in storm drains and ditches. Surface run-off from the north part of the plant site is collected by Ditch 1 and flows through the ditch and discharges through the morning glory and culvert into the Ditch 2 and by the same process into the Ditch 3 and finally into Ditch 4. Each of the morning glories is fitted with three manually operated level control valves. Surface run-off from the surrounding area of the Generating Stations is collected by Ditch 4 running east parallel to the railway tracks ultimately discharging to the surface runoff pond. This pond occasionally overflows (every five years or so) but generally discharges through infiltration to groundwater and by evaporation loss (Figure 2).

GCC maintains a similar stormwater sediment control system south of the Station; this system utilizes five ponds in a cascading system. All ditches in the surface runoff control system are naturally excavated with no artificial liners installed. Although leakage into underlying groundwater occurs, there likely is some retardation due to settlement of fines at the base of all ponds.

2.3 Wastewater Drainage and Control

The north and south wastewater ponds receive most of the wastewater via pipeline from the power house and service water pump house. Some water is directed to the river water screens for de-icing in the winter. Process streams directed to the wastewater ponds include:

• turbine condenser cooling water, • clarifier sludge pit, • neutralizer tank; bottom ash system; surge and settling tank, • dewatering bins, • drainage transfer pit, and • laboratory reagents.

The capacity of the north pond is 5,300m3 cubic while the capacity of the south pond is 10,000m3 and both are equipped with oil skimmers. The effluent pumping facility

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has the ability to recirculate water from the ponds. This allows one pond to be isolated for further settling prior to discharge to maintain water quality.

2.3 Generating Station Operations

The existing HR Milner Generating Station does not utilize any groundwater in its operations. All cooling and process water is from the Smoky River and domestic water is hauled by truck from Grande Cache.

Potential sources of impact to local groundwater at the existing Station and proposed expansion include: • holding tanks and water line leaks on the process system (including fire suppression system), waterworks or domestic wastewater systems, • discharge of process water blowdown to the settling ponds, • chemical/fuel spillage, and • treatment chemicals (water softening primarily) in process water discharged through the settling ponds.

There are no facilities present or planned for deep well disposal or direct injection to groundwater.

3.0 GEOLOGY

3.1 Bedrock Geology

The uplands area surrounding the Station consist of front range mountains formed by the Cretaceous Luscar Group as noted on the stratigraphic column presented as Figure 3 (Appendix 1). The coal bearing sequence of this group is the Grande Cache Member which is characterized by thicker, grey, medium to coarse-grained sandstone interbedded with thinner layers of black shale and coal3. Adjacent bedrock outcrops in the lower portion of Smoky River Valley consist of the underlying Torrens Member, Moosebar Formation and the Gladstone Formation as shown on the bedrock Geology Map (Figure 4, Appendix 1). The structural geology at depth on both the northern and southern sides of the valley is shown on the cross-section presented as Figure 5. This

3 Geological Map Grande Cache Area, Alberta; Alberta Research Council Map Sheet 83E/14, 1986

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figure shows the extent of local folding that as occurred as part of orogenic uplift. In addition, numerous thrust faults are present, including the Mason Thrust fault just west of the Generating Station.

3.2 Surficial Geology

The limbs of the southern Smoky River valley slope are partially covered by glaciofluvial valley fill terraces up to an elevation of approximately 940masl, as shown on Figure 4. This post-glacial deposit consists of poorly graded and sorted silty gravel with sand that was deposited throughout much of the Smoky River valley during deglaciation. It is considered part of the same formation that crops out along the Muskeg River Valley on the south side of the Smoky River Valley. This formation has been locally incised and eroded by intermittent streams cascading down the slopes of uplands on both sides of the river. A thin veneer of wind-blown loess overlies some areas of the glaciofluvial terraces as well as local outcrops of exposed bedrock.

The main Station and proposed expansion areas are located on a point bar deposit laid down as a Quaternary alluvial deposit from the Smoky River which is a braided stream in a confined valley. The Smoky River at this location has a relatively high gradient and is capable of carrying both large cobbles/boulders as well as finer grained silt and sand. The alluvial deposits underlying the point bar consist of loose interbedded sand, silt and gravel from ground surface to elevations ranging from 860 to 880masl.

Recent groundwater exploration at the GCC Plant Site has shown the extensive nature of the alluvial deposits and the locally variable depth to bedrock, as shown on Figure 6. A coarse gravel deposit is present immediately overlying the bedrock in this area (shown as the Deep Gravel on Figure 6) and is interpreted to be pre-glacial in origin. In active operations areas, localized deposits of surface fill consisting of clay, coal and silt is present4. Copies of all borehole and monitor well logs from both the existing Milner and GCC groundwater monitoring networks are presented in Appendix 2.

4.0 HYDROGEOLOGY

4 Deep Groundwater Supply Investigation; Unpublished Report by Westcan Watertech Inc. for Grande Cache Coal Corporation, 2008.

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4.1 Bedrock Aquifers

The Hydrogeological Reconnaissance Map of the area shows relatively low yields (less than 20 Lpm) can be expected from the lower members of the Cretaceous Gates Formation, with increased yields expected in the upper zones of Grande Cache and Moosebar Members5 (Figure 7). The 1977 Hydrogeological Reconnaissance Map and Report notes that a number of dry wells have been drilled and are not uncommon in the bedrock of the Grande Cache area. The area contains a number of shallow springs that discharge to surface that may be associated with locally outcropping fractured sandstone. Localized seepages of bedrock derived groundwater occur along the valley slopes where fractured, localized saturated zones subcrop near the ground surface in topographically lower drainage channels. Potential aquifers were discussed in the 1977 report and were summarized on the stratigraphic column presented as Figure 3.

As part of the GCC exploration and development, several monitor wells have been drilled in the bedrock formations adjacent to the plant Site. Typically, some fractured sandstone units were intersected during drilling and groundwater produced average rates of less than at 0.1 L/s. Dry holes are common particularly where coarser, more indurated sandstone is not present6.

The average hydraulic conductivity of the fractured sandstone may be as high as 10-5 m/s but can often be less than 10-8m/s, which is considered typical of low to moderately fractured sandstone or siltstone bedrock typically found in the area. A 24 hour pumping test was conducted with a test hole at an elevation of 1700masl but found that the initial water level (39.90m) was drawn down to the pump intake after only 17 hours of pumping. Very slow recovery limited the production feasibility and the well was converted to a long term monitoring well.

Depth to groundwater was measured in numerous test holes and monitor wells and found to range from less than ten metres to greater than 110m depth with an average depth to water of 39m. Water level monitoring has shown water levels vary by as much as three metres seasonally. Highest water levels occur in early May with gradual decline until December when water levels remain at the lowest levels throughout the remainder of the winter. Groundwater temperatures range between two and six degrees Celsius depending upon topographic elevation.

5 Hydrogeology of the Mount Robson-Wapiti Area, Alberta; Report 76-5 Alberta Research Council, 1977. 6 Hydrogeological Evaluation of Bedrock Aquifers for No. 8 Mine; unpublished report by Westcan Watertech Inc. for Grande Cache Coal Corporation, 2006-2007.

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Although coarser grained sandstone present in the Grand Cache Member suggests some primary porosity, fracture induced secondary permeability is clearly the more important aspect leading to variations in aquifer transmissivity. It can be concluded that the bedrock aquifers are very limited in areal extent and are dependent upon the development of secondary fracture permeability. Given the lack of topographically low areas, groundwater accumulation in the localized fractures tends to be temporal and can be depleted relatively rapidly at least at elevations above 1300masl.

4.2 Surficial Aquifers

The entire Station and expansion area is covered by both recent and preglacial surficial aquifers. Depth to bedrock is consistently greater than 35m and has not been extensively tested and is not currently used as a groundwater supply. The surficial aquifers represent significant resources and all discussion is subsequently restricted to the local surficial aquifers.

4.2.1 Shallow Gravel Aquifer

The shallow alluvial sand and gravel aquifer underlying the Station contains coarse sand, gravel and cobbles with the coarsest grain size at depth. The shallow aquifer unconfined and is within ten metres of ground surface in the flood plain area (elevation approximately 910masl). This aquifer is hydraulically linked with water levels in the Smoky River (from observed water levels reported in the Annual Reports2). This shallow aquifer is considered to be alluvial in nature from post glacial gravel deposits from the Smoky River.

4.2.3 Deep Gravel Aquifer

The sand and gravel aquifer (referred to as the deep gravel aquifer) intersected by groundwater supply boreholes at GCC is a limestone/dolomite coarse gravel/cobble deposit likely forming a basal aquifer overlying bedrock at an average elevation of 865masl (see Figure 6). Given the much higher content of limestone in the gravels, it is interpreted to be a pre-glacial alluvial valley deposit as the closest limestone deposits are over 20km upstream in the Smoky River Valley.

The deep gravel aquifer is confined by over 30m of relatively low hydraulic conductivity sandy silt and silty sand that results in piezometric heads of over 40m. The

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groundwater elevation in the deep gravel aquifer in April 2008 was approximately two metres below the Smoky River (as shown on Figure 6).

4.3 Groundwater Movement

4.3.1 Shallow Gravel Aquifer

The orientation of shallow groundwater movement in the river valley is seasonally variable. Typically, groundwater moves down gradient toward the Smoky River during most of the year when the Smoky River is at low or mean flow (July to April) with reversed recharge from the river occurring within 50m of the river bank during brief high river flows in May or June. In 2006, groundwater discharge was eliminated during an estimated 30 days when river levels at the GCC Plant Site were higher than at monitor well GCC2-051. During the remainder of the year the shallow aquifer discharges to the Smoky and is locally recharged by infiltration of precipitation.

4.3.2 Deep Gravel Aquifer

The deep gravel aquifer is recharged from the Smoky River at some point upgradient but can be no closer than 700m from the Station and possibly as much as five kilometres upstream. This horizontal flow/recharge pattern is consistent to the vertical leakage recharge concluded by Mollard and Associates for the existing potable waterwell at the GCC Plant Site7. Current evidence does not indicate a seasonal reversal of flow in the deep aquifer; rather, continuous recharge from the Smoky River with groundwater movement down-gradient following the valley of the Smoky River. Although the deeper aquifer appears to be confined, there is likely a component of recharge from the overlying shallow aquifer.

4.4 Groundwater Users

The existing Milner Generating Station does not utilize groundwater as domestic water as domestic water is hauled by truck from Grande Cache. The nearby GCC plant site uses a licensed 35m industrial water supply well for potable water use. The nearest domestic users are located approximately four kilometres downstream at Wanyandie Flats where at least two water supply wells are used as a manual community supply (logs in Appendix 2; location shown on Figure 8). One user (Tom Wanyandie) has a

7 Groundwater Exploration and Development, McIntyre Porcupine Mines, Grande Cache, Alberta; Unpublished report prepared by JD Mollard and Associates, 1969.

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dedicated well that was installed in 1975. The Ascheniwuche Nation constructed a new community well in 2006. At least one old hand pump well is also present in the community but no other waterwell logs are on record (there are several chemical samples on record). There is one chemistry record from a hand dug well approximately four kilometres upstream from the Plant Site. A summary of the existing waterwell users on file is presented in the Table 1, following.

Table 1 – Existing Groundwater Users

Name Number Location Depth (m) Comments

Alberta Municipal Inactive; old hand pump? 0439214 7-24-58-8-W6M 6.1 Affairs Log questionable Tom Wanyandie 0439220 NE-24-58-8-W6M 9.1 Inactive; old hand pump? Wanyandie Flats #2 0439230 10-24-58-8-W6M 9.1 Highest utilization? Wanyandie Flats #2 0439234 10-24-58-8-W6M 9.1 Currently inactive? Ascheniwuche Nation 1105026 NE-24-58-8-W6M 8.5 Installed 2007 Coelen Camp (old Chemistry only; hand 0439190 05-04-58-8-W6M 9.1 sawmill site) dug, currently inactive?

As noted earlier, there is no groundwater currently utilized at the Generating Station nor is any planned for the expansion phase.

4.5 Quantitative Hydrogeology

4.5.1 Shallow Gravel Aquifer

Hydraulic conductivity (K) testing carried out at the GCC Plant Site in 2001 found that the alluvial aquifer yielded mean K values in the order of 7 X 10-6 m/s (0.6m/day). Further slug testing was conducted with monitor wells located in the Plant Site Area in 2005 and confirmed an average hydraulic conductivity of 0.6m/day1.

While K is variable throughout the site (no doubt due to local variation in grain size as a result of variable depositional environment), the mean value is considered representative of the entire shallow aquifer section.

Hydraulic gradient (ί) is a variable depending upon groundwater and river water elevation. Monthly groundwater gradient from the GCC Plant Site to the Smoky River was calculated based on the relative water levels from monitor wells to the river from 2004 to 2007. Hydraulic gradients over the Plant Site and have been found to range

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from +0.011 (late winter to the river) and -0.022 (from the Smoky River to groundwater for a few weeks in early June 2006). Groundwater movement is generally parallel with the Smoky River throughout most of the year. Recharge of groundwater from the Smoky occurs for only a few weeks during the spring freshet and does not extend more than 50m from the river itself.

Average linear pore water velocity is therefore controlled by the transient nature of the variable hydraulic gradient. Given an estimated bulk density of 0.30 (porosity, ), the maximum pore water velocity during groundwater movement toward the Smoky River is calculated as 0.022m/day as per the following methodology:

v = Ki = 0.022 m/day 

4.5.2 Deep Gravel Aquifer

5.0 WATER QUALITY

Groundwater quality has been monitored at the HR Milner Generating Station since 1990 and reported annually until 2006. A recent amendment to their operating approval has reduced the reporting requirement to biannual. Thus, there is an excellent groundwater monitoring network and baseline database available which forms the basis of this discussion. The existing HR Milner monitoring network consists of six monitoring wells (at locations shown on Figure 2) with sampling conducted in the spring and fall. Since 2006, actual sampling days have been coordinated with GCC so both sites are sampled on the same day. Actual chemical data collected from the monitoring wells since 2004 is presented in Appendix 3.

5.1 General Water Quality Observations

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A comparison of local water quality is presented as a Piper Diagram on Figure 10. This diagram shows the typical water quality of the shallow and deep aquifers in comparison with the Smoky River. There are three groupings of water quality based on source and location:

• Smoky River Water typically of lower TDS calcium bicarbonate type (Upper Smoky River), • The shallow alluvial aquifer typically of the calcium bicarbonate type with increasing sodium (GCC1-05, GCC2-05, MES-02, MES-04, MW1, MW2, MW3C. MW4, MW5, MW6), and • The deeper preglacial gravel aquifer containing softer water with an increased proportion of sodium and chloride (Existing GCC well, PW1-08, TH1-08).

With the common exception of manganese and TDS, all groundwater samples collected from the existing HR Milner Station groundwater monitoring wells in 2006 met the applicable guidelines (Canadian Drinking Water Quality Guidelines [CDWQG]). The guidelines for manganese and TDS are considered aesthetic and are commonly exceeded in natural groundwater from alluvial gravel aquifers. There is virtually no detectable concentration of organic carbon, hydrocarbons (F1 and F2 fractionation) and phenols. All trace elements (with the exception of manganese and occasionally dissolved iron) met the CDWQG in 2006 (see data in Appendix 3).

Water quality was relatively consistent at each location during both the spring and fall sampling events of 2006. There is evidence of a slight decrease in concentration of TDS, sodium, chloride and sulphate at MIL-MW1 during 2006. However, the concentrations were within the historical range of previous water quality data.

The concentration of TDS is affected by geographic position in relation to the Smoky River. Samples collected from wells MIL-MW2, MIL-MW4 and MIL-MW5 show consistently lower concentrations of TDS, chloride and sodium than samples from locations further away from the river. The higher chemical concentrations from the more river distant monitors (MIL-MW1, MIL-MW3C and MIL-MW6), are considered more representative of groundwater under minimal dilution from the Smoky River.

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5.2 Groundwater Quality Trend Analysis

Samples have been collected for over 15 years from the HR Milner Generating Station and historical water quality data is available to observe general and specific trends over time (see historic water quality data in Appendix 3). While most analyzed parameters have tended to remain consistent (with occasional unique spikes or peaks), noticeable trends have been evident for chloride and sodium, and possibly, sulphate and TDS. Key trend analysis graphs for major analytical are shown and discussed in the following sections.

5.2.1 Chloride

Chloride concentrations showed a noticeable increase at all monitored locations over the period 1990 to 2000. A dramatic and continuous decline in chloride concentration was evident from 2001 until May 2004. The chloride concentration since 2004 has varied slightly at several locations but shows general consistency for the last three years of monitoring.

5.2.2 Sodium

Sodium concentrations also show a slight rise in average concentration until 1999 with a more noticeable concentration decrease until 2003. From 2004 to 2005, the concentration of sodium increased dramatically at MIL-MW1 but has remained relatively consistent since. There is a general decline in sodium concentration at MIL- MW2 since 1999 while all other monitoring data show consistency since 2004.

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Sodium

1 2 3C 4 5 6 GCDWQ AO <= 200 mg/L

30 Concentration (mg/L)

10 Jul-91 Oct-98 Jun-99 Jun-96 Oct-96 Oct-00 Jun-01 Oct-01 Jun-02 Oct-02 Oct-04 Jun-05 Oct-05 Jun-06 Oct-06 Oct-91 Apr-98 Feb-93 Feb-94 Feb-95 Feb-96 Apr-91 Sep-97 Nov-99 Nov-92 Nov-93 Nov-94 Nov-95 Nov-90 May-97 May-00 May-03 May-04 May-92 Aug-92 May-93 Aug-93 May-94 Aug-94 May-95 Aug-95

5.2.3 Sulphate

The sulphate concentration has also followed a similar trend as sodium and chloride although the average concentration increase from 1990 to 2003 is relatively minor and notably less than for sodium and chloride. The concentration of sulphate at MIL- MW2, MIL-MW4 and MIL-MW5 has declined slightly but remained consistent at all other monitored locations. The relatively high concentration of sodium (and TDS) at MIL-MW6 is indicative of a strong groundwater component with little river water mixing.

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Sulphate

350

300 1 2 3C 4 5 6 GCDWQ AO <= 500 mg/L

250

200

150 Concentration (mg/L) Concentration

10 0

50 Jul-91 Oct-98 Jun-99 Oct-00 Jun-01 Oct-01 Jun-02 Oct-02 Oct-03 Oct-04 Jun-05 Oct-05 Jun-06 Oct-06 Jun-96 Oct-96 Oct-91 Apr-91 Apr-98 Feb-96 Feb-95 Feb-94 Feb-93 Nov-90 Nov-99 Sep-97 Nov-95 Nov-94 Nov-93 Nov-92 May-00 May-03 May-04 May-97 May-95 Aug-95 May-94 Aug-94 May-93 Aug-93 May-92 Aug-92

5.2.4 Total Dissolved Solids (TDS)

Given the increase and decrease in key chemical concentrations it would be expected to see a similar trend in overall chemistry as demonstrated by TDS. The TDS trend diagram remained fairly consistent at MIL-MW1 (with the exception of a spike in 2005), MIL-MW3C and MIL-MW5 and since 2003 at MIL-MW2 and MIL-MW4. There was evidence of a slight decline in TDS from 2000 to 2003 at MIL-MW2 and MIL-MW4 and there was also a decline in TDS concentration at MIL-MW6 since installation in 2004.

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Total Dissolved Solids

1400

1200 1 2 3C 4 5 6 GCDWQ AO <= 500 mg/L

1000

800

600 Concentration (mg/L) Concentration

400

200 Jul-91 Oct-98 Jun-99 Jun-96 Oct-96 Oct-00 Jun-01 Oct-01 Jun-02 Oct-02 Oct-03 Oct-04 Jun-05 Oct-05 Jun-06 Oct-06 Oct-91 Apr-98 Feb-93 Feb-94 Feb-95 Feb-96 Apr-91 Sep-97 Nov-99 Nov-92 Nov-93 Nov-94 Nov-95 Nov-90 May-97 May-00 May-03 May-04 May-92 Aug-92 May-93 Aug-93 May-94 Aug-94 May-95 Aug-95

5.3 Water Quality Discussion

The observed sodium and chloride concentration increase up to 2000 and general decline until 2003 and localized minor increase thereafter was determined to be the result of water softening chemicals associated with the operation of the former Smoky River Coal Preparation Plant and recommissioning by Grande Cache Coal Corporation since 2003.

Monitoring evidence from the tailings ponds on the opposite side of the river had indicated a rise in concentration of sodium and chloride that was deemed to be the result of leakage of process water softening chemicals8. The coal preparation plant operation was halted in early 2000 but resumed operation in 2003 under the mandate of GCC. Continued monitoring of sodium and chloride concentrations is a critical element of the groundwater monitoring program currently carried out by GCC and is reported under their Approval 155804-00-021.

Current evidence may indicate increased concentration of sodium and chloride in coal preparation process water is intrinsic leaching of shale partings during the coal

8 Application for Approval and Environmental Impact Assessment for the Grande Cache Coal Project; EIA Application to Alberta Environment by Grande Cache Coal Corporation. October 2001

Hydrogeological Baseline Report, Maxim Power Corporation, near Grande Cache, Alberta; Westcan Watertech Report, July 28, 2008 Page 19

preparation process. Future monitoring will help clarify the extent and possible nature of the observed general rise in sodium and chloride up to 2000 and more recently since 2004.

6.0 CONCLUSIONS

The limbs of southern Smoky River valley slope is partially covered by glacio-fluvial valley fill terrace up to an elevation of approximately 940masl. This post-glacial deposit consists of poorly graded and sorted silty gravel with sand that was deposited throughout much of the Smoky River valley during deglaciation. This formation has been locally incised and eroded by intermittent streams cascading down the slopes of uplands on both sides of the river.

Hydrogeological Baseline Report, Maxim Power Corporation, near Grande Cache, Alberta; Westcan Watertech Report, July 28, 2008 Page 20

no closer than 700m from the Station and possibly as much as five kilometres upstream.

Hydrogeological Baseline Report, Maxim Power Corporation, near Grande Cache, Alberta; Westcan Watertech Report, July 28, 2008 Page 21

trace elements, with the exception of manganese and occasionally dissolved iron, met the CDWQG.

Hydrogeological Baseline Report, Maxim Power Corporation, near Grande Cache, Alberta; Westcan Watertech Report, July 28, 2008 Page 22

7.0 CLOSURE

The information provided in this monitoring report is based upon work undertaken according to standard hydrogeological and scientific practices by a trained and licensed professional geologist and environmental technologist. This report was prepared by Doug Bernard, P.Geol.

Respectfully submitted,

WESTCAN WATERTECH INC.

Doug Bernard, P.Geol. Principal Hydrogeologist

Hydrogeological Baseline Report, Maxim Power Corporation, near Grande Cache, Alberta; Westcan Watertech Report, July 28, 2008 Page 23

Appendix 1: Figures GENERATING STATION

CLIENT: DRAWN: WWI DRAWING: SCALE (km) TLI LOCATION PLAN REGIONAL SETTING SCALE: REV. NO.: 0 MAXIM POWER CORP 2 0 2 4 6 8 AS NOTED

CONTOUR INTERVAL: 500 FEET DATE: 2008-06-09 FIGURE 1 SURFACE RUNOFF POND (DISCHARGE TO WETLAND) WASTEWATER PONDS

NORTH SOUTH

RAW COAL STOCKPILE

DITCH 4 DITCH 2 DITCH 3 DITCH 1

COAL PROCESSING PLANT COOLINGPUMP TOWER HOUSE

H.R. MILNER COOLING TOWER GENERATING STATION SERVICEPUMP WATER HOUSE

SWITCH PLANT SITE YARD SETTLING POND CLEAN COAL STOCKPILE

SMOKY RIVER

CLIENT: DWN BY: WWI DRAWING: LEGEND SCALE (m) TLI MILLENIUM PLANT SITE ENVIRONMENTAL REVISED BY: PLANT SITE AREA GRANDE CACHE REV. NO.: SERVICES 50 0 50 100 MAXIM POWER CORP COAL SCALE 0 CONTOUR INTERVAL: 50 METRES CONNECT AS NOTED MILNER POWER REFERENCE DRAWINGS SUPPLIED DATE: FIGURE 2 VALVE BY GRANDE CACHE COAL 2008-06-09 CLIENT: DRAWN: WWI DRAWING: TLI STRATIGRAPHIC STRATIGRAPHIC SCALE: REV. NO.: AS NOTED 0 COLUMN MAXIM POWER CORP DATE: 2008-06-26 FIGURE 3 BEDROCK KASKAPAU FORMATION NO. 4 SEAM DUNVEGAN FORMATION NO. 10 SEAM SHAFTSBURY FORMATION NO. 11 SEAM MOUNTAIN PARK MEMBER ANTICLINE AXIS TORRENS MEMBER SYNCLINE AXIS MOOSEBAR MEMBER GLADSTONE MEMBER SURFICIAL CADOMIN FORMATION GLACIO-FLUVIAL ALLUVIAL SAND & GRAVEL

DWN: CONTOUR INTERVAL: 10 METRES TEST HOLE/ TLI EXPLORATION 8MW-1 FIGURE 4 REFERENCE DRAWINGS SUPPLIED DATE: MONITORING BY GRANDE CACHE COAL DRILL HOLE REGIONAL GEOLOGY 2009-01-10 CROSS SECTION WELL No. 11 Seam No. 10 Seam No. 4 Seam

Torrens SmokyRiver Moosebar Gladstone

CLIENT LEGEND GLACIO-FLUVIAL FIGURE 5 NO. 4 SEAM ALLUVIAL SAND & GRAVEL NO. 10 SEAM TORRENS MEMBER BEDROCK GEOLOGICAL NO. 11 SEAM GLADSTONE MEMBER MOOSEBAR FORMATION CROSS-SECTION A-A' CLIENT: LEGEND FIGURE 6 HORIZONTAL SCALE (m) GEOLOGICAL 25 0 25 50 75 100 CROSS-SECTION B-B' CLIENT: DRAWN: WWI DRAWING: TLI REGIONAL HYDRO APPROX SCALE (km) REGIONAL SCALE: REV. NO.: AS NOTED 0 HYDROGEOLOGY 8 0 8 16 24 32 MAXIM POWER CORP DATE: 2008-06-26 FIGURE 7 3 5 6 2 4

FLOOD CREEK GENERATING DISPOSAL STATION FACILITY

5 km

CLIENT LEGEND FIGURE 8 OTHER GROUNDWATER 4 USERS MAXIM POWER CORP CLIENT: LEGEND WWI DRAWING: GROUNDWATER QUALITY GROUNDWATER QUALITY SAMPLE NAMES AND LOCATIONS DWN BY: TLI

AS SHOWN IN REPORT DATE: 2009-01-12 (PIPER PLOT) MAXIM POWER CORP PIPER PLOT FIGURE 9

Appendix 2: Monitoring Wells and Waterwell Logs

Appendix 3: Analytical Data Base H. R. Milner Station - Groundwater Trends

Bicarbonate

1000

900

800

700 1 1A 600 2 2A 500

mg/L 3

400 3A 3C 300 4 5 200

100

0 Jul-91 Apr-91 Apr-98 Oct-91 Oct-96 Oct-98 Oct-00 Oct-01 Oct-02 Oct-03 Jun-96 Jun-99 Jun-01 Jun-02 Feb-93 Feb-94 Feb-95 Feb-96 Aug-92 Aug-93 Aug-94 Aug-95 Sep-97 Nov-92 Nov-90 Nov-93 Nov-94 Nov-95 Nov-99 May-92 May-93 May-94 May-95 May-97 May-00 May-03

BTEX (Benzene, Toluene, Ethylbenzene, Xylenes)

0.0020

June/01: Toluene was 0.001 mg/L; the other parameters were <0.001 mg/L May/03: Benzene was 0.001 mg/L and Xylene was 0.002 mg/L; the other parameters were 0.0015 <0.001 mg/L 1 1A 2 2A 0.0010 3 mg/L 3A 3C 4 5 0.0005

0.0000 Oct-96 Oct-97 Oct-98 Oct-99 Oct-00 Oct-01 Oct-02 Oct-03 Jun-96 Jun-97 Jun-98 Jun-99 Jun-00 Jun-01 Jun-02 Jun-03 Feb-97 Feb-98 Feb-99 Feb-00 Feb-01 Feb-02 Feb-03

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Calcium 300

250

200 1 1A 2 150 2A

mg/L 3 3A 3C 100 4 5

CbCarbonat e

20 1 1A 2 2A 15

mg/L 3 3A 3C 10 4 5

0 Jul-91 Oct-96 Apr-98 Oct-98 Apr-91 Oct-91 Oct-00 Oct-01 Oct-02 Oct-03 Jun-96 Jun-99 Jun-01 Jun-02 Feb-93 Feb-94 Feb-95 Feb-96 Sep-97 Nov-90 Aug-92 Nov-92 Aug-93 Nov-93 Aug-94 Nov-94 Aug-95 Nov-95 Nov-99 May-97 May-92 May-93 May-94 May-95 May-00 May-03

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Chemical Oxygen Demand

1600

1400

1200

1 1000 1A 2 2A 800

mg/L 3 3A 600 3C 4 5 400

200

0 Jul-91 Oct-96 Apr-98 Oct-98 Oct-00 Oct-01 Oct-02 Oct-03 Apr-91 Oct-91 Jun-96 Jun-99 Jun-01 Jun-02 Feb-96 Feb-95 Feb-94 Feb-93 Sep-97 Nov-99 Aug-95 Nov-95 Aug-94 Nov-94 Aug-93 Nov-93 Nov-90 Aug-92 Nov-92 May-97 May-00 May-03 May-95 May-94 May-93 May-92

Chlorid e

140

120 1 2 3C 4 5 6

GCDWQ AO <= 250 mg/L 100

Concentration (mg/L) Concentration 40

0 Jul-91 Apr-98 Oct-98 Oct-96 Oct-00 Oct-01 Oct-02 Oct-03 Oct-04 Apr-91 Oct-91 Jun-99 Jun-96 Jun-01 Jun-02 Jun-05 Feb-93 Feb-94 Feb-95 Feb-96 Sep-97 Nov-99 Aug-92 Nov-92 Aug-93 Nov-93 Aug-94 Nov-94 Aug-95 Nov-95 Nov-90 May-97 May-00 May-03 May-04 May-92 May-93 May-94 May-95

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Dissolved Organic Carbon 14

1 1A 8 2 2A

mg/L 3 6 3A 3C 4 4 5

0 Oct-96 Apr-98 Oct-98 Oct-00 Oct-01 Jun-96 Jun-99 Jun-01 Jun-02 Sep-97 Nov-99 May-97 May-00 May-03 Oct-02* Oct-03*

Con duc tiv ity (Fi eld) 4500

4000

3500

3000 Series1 Series2 2500 Series3 Series4

umhos 2000 Series5 Series6 Series7 1500 Series8 Series9 1000

500

0 Date Jul-91 Oct-96 Apr-98 Oct-98 Apr-91 Oct-91 Oct-00 Oct-01 Oct-02 Oct-03 Oct-04 Oct-05 Jun-96 Jun-99 Jun-01 Jun-02 Jun-05 Feb-93 Feb-94 Feb-95 Feb-96 Sep-97 Nov-90 Aug-92 Nov-92 Aug-93 Nov-93 Aug-94 Nov-94 Aug-95 Nov-95 Nov-99 May-97 May-92 May-93 May-94 May-95 May-00 May-03 May-04

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Fluoride 0.9

GCDWQ MAC = 1.5 mg/L 0.8

0.7

0.6 1 1A 0.5 2 2A mg/L 0.4 3 3A 3C 0.3 4 5 0.2

0.1

0 Jul-91 Oct-96 Apr-98 Oct-98 Oct-01 Oct-02 Oct-03 Apr-91 Oct-91 Jun-96 Jun-99 Jun-01 Jun-02 Feb-96 Feb-95 Feb-94 Feb-93 Sep-97 Nov-99 Nov-99 Aug-95 Nov-95 Aug-94 Nov-94 Aug-93 Nov-93 Nov-90 Aug-92 Nov-92 May-97 May-00 May-03 May-95 May-94 May-93 May-92

MiMagnesium 120

100

80 1 1A 2

60 2A

mg/L 3 3A 3C 40 4 5

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Nitrate 8 GCDWQ MAC = 45 mg/L (equivalent to 10 mg/L as nitrate-nitrogen)

*Nitrate and Nitrite analyzed 6

5 1 1A 2 4 2A

mg/L 3 3A 3 3C 4 5 2

0 Jul-91 Oct-96 Apr-98 Oct-98 Oct-00 Oct-01 Oct-02 Oct-03 Jun-96 Jun-99 Jun-01 Jun-02 Feb-96 Feb-95 Feb-94 Feb-93 Sep-97 Nov-99 Aug-95 Nov-95 Aug-94 Nov-94 Aug-93 Nov-93 Aug-92 Nov-92 May-97 May-95 May-94 May-93 May-92 Apr-91* Oct-91* Nov-90* May-00* May-03*

Nitrit e

0.6

0.5

1 0.4 1A 2 2A 0.3 3 mg/L 3A 3C

0.2 4 5

0.1

0 Oct-96 Apr-98 Oct-98 Oct-00 Oct-01 Oct-02 Oct-03 Jun-96 Jun-99 Jun-01 Jun-02 Sep-97 Nov-99 May-97 May-00* May-03*

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Oil & Grease 7.0

6.0

5.0

1 1A 4.0 2 2A

mg/L 3 3.0 3A 3C 4 2.0 5

1.0

0.0 Jul-91 Oct-96 Apr-98 Oct-98 Oct-00 Oct-01 Oct-02 Oct-03 Apr-91 Oct-91 Jun-96 Jun-99 Jun-01 Jun-02 Feb-96 Feb-95 Feb-94 Feb-93 Sep-97 Nov-99 Aug-95 Nov-95 Aug-94 Nov-94 Aug-93 Nov-93 Nov-90 Aug-92 Nov-92 May-97 May-00 May-95 May-94 May-93 May-92 May-03* Jun-03** Nov-03**

pH 9

GCDWQ AO 6.5 - 8.5

8.5

8 1 1A 2 7.5 2A 3 3A 3C 7 4 5

6.5

6 Jul-91 Oct-96 Apr-98 Oct-98 Apr-91 Oct-91 Oct-00 Oct-01 Oct-02 Jun-96 Jun-99 Jun-01 Jun-02 Feb-93 Feb-94 Feb-95 Feb-96 Sep-97 Nov-90 Aug-92 Nov-92 Aug-93 Nov-93 Aug-94 Nov-94 Aug-95 Nov-95 Nov-99 May-97 May-92 May-93 May-94 May-95 May-00 May-03

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Phenol 30

GCDWQ (1978) Limit = 2 ug/L

20 1 1A 2 15 2A ug/L 3 3A 3C 10 4 5

PtPotass ium 16

1 10 1A 2 8 2A

mg/L 3 3A 6 3C 4 5 4

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Sodium

1 2 3C 4 5 6 GCDWQ AO <= 200 mg/L

Concentration (mg/L) Concentration 30

10 05 - Jul-91 Apr-98 Oct-98 Oct-96 Oct-00 Oct-01 Oct-02 Oct-04 Apr-91 Oct-91 Oct Jun-99 Jun-96 Jun-01 Jun-02 Jun-05 Feb-93 Feb-94 Feb-95 Feb-96 Sep-97 Nov-99 Aug-92 Nov-92 Aug-93 Nov-93 Aug-94 Nov-94 Aug-95 Nov-95 Nov-90 May-97 May-00 May-03 May-04 May-92 May-93 May-94 May-95

SlhtSulphate

350

300 1 2 3C 4 5 6 GCDWQ AO <= 500 mg/L

250

200

150 Concentration (mg/L) Concentration

100

50 Jul-91 Apr-98 Oct-98 Oct-96 Oct-00 Oct-01 Oct-02 Oct-03 Oct-04 Oct-05 Apr-91 Oct-91 Jun-99 Jun-96 Jun-01 Jun-02 Jun-05 Feb-93 Feb-94 Feb-95 Feb-96 Sep-97 Nov-99 Aug-92 Nov-92 Aug-93 Nov-93 Aug-94 Nov-94 Aug-95 Nov-95 Nov-90 May-97 May-00 May-03 May-04 May-92 May-93 May-94 May-95

NOTE: Values below the detection limit have not been graphed H. R. Milner Station - Groundwater Trends

Temperature (Field) 16 GCDWQ AO <= 15 C

1 10 1A 2 8 2A

deg. C deg. 3 3A 6 3C 4 5 4

Tot al Di ssol ved S olid s

1400

1200 1 2 3C 4 5 6 GCDWQ AO <= 500 mg/L

1000

800

600 Concentration (mg/L) Concentration

400

200 Jul-91 Apr-98 Oct-98 Oct-96 Oct-00 Oct-01 Oct-02 Oct-03 Oct-04 Oct-05 Apr-91 Oct-91 Jun-99 Jun-96 Jun-01 Jun-02 Jun-05 Feb-93 Feb-94 Feb-95 Feb-96 Sep-97 Nov-99 Aug-92 Nov-92 Aug-93 Nov-93 Aug-94 Nov-94 Aug-95 Nov-95 Nov-90 May-97 May-00 May-03 May-04 May-92 May-93 May-94 May-95

NOTE: Values below the detection limit have not been graphed