Environmental Geology Field Trips GEOL312

April 12th, 2024

This semester for me was bitter sweet, as I am at the end of my undergraduate degree after four and a half years at Vancouver Island University in the Geoscience Major. The Environmental Geology class was truly beneficial for me as I am planning a career in an environmental field and this class focus on so many aspects to take into accounts when making decisions as a future environmental geoscientist (not just rocks), or as a professional in environmental policies. Through seven field trips, class activities and lectures I felt more confident to undertake a career in this field. The course covered multiple aspects with the following goals:

• Studying the earth’s surface, oceans, and atmospheres to better understand issues related to interconnectivity between land, water, air, and biota.
• Identifying, assessing, and mitigating the impacts that geological hazards have on humans.
• Assessing and managing surface water and groundwater to ensure sufficient supply of clean water.
• To understand how and when there is contamination of water, and also flooding and droughts.
• Managing  domestic, industrial, and mining waste in a geological context to consider disposal techniques, minimize contamination and the dispersal of pollutants, along with issues related to recycling. 
• Investigating fossil fuels (coal, oil, gas, conventional & unconventional) and alternative energy (nuclear, hydro, solar, wind, tidal & run-of-river) in terms of efficiency, power output, costs and environmental impacts including carbon emissions.

A Career in Environmental Policies?

I have spent four and a half year studying science with the personal ambition to help somehow solving environmental problems, but this last year of studying really opened my eyes on the importance of policies to solve those issues. Through the climatology class and the environmental geology class I realized that environmental problems are very strongly linked to social dynamics and politics, and I am now considering pursuing a master in environmental policies in the United Kingdom, or teaching. In many field trips completed in GEOL 312, the geoscientists or experts knew the local issues but the politics and public were slowing down the effort to implement those changes (legally, budget, etc.). For example at the landfill, flaring of methane was an excellent mitigation technique to reduce emissions of greenhouse gases but the product of flaring was wasted, because old business contracts from potential buyers of this product (FortisBC) was slowing down their capacity to do so. Globally, if we are serious about curbing the worst effect of climate changes, many policies must be adapted to help scientists reduce anthropogenic greenhouse gases emissions and negative impacts from anthropogenic activities., not impede them. Additionally, I am a little seduce by the idea of wearing a wig (see Figure 1) in the UK (should I work in policies there).

Figure 1. A symbol of power and respect for the law, in the UK.

April 8th, 2024

Introduction

On April 8th, 2024 students from the Environmental Geology class at Vancouver Island University took a tour of the GeoExchange directly on Vancouver Island University Campus (Vancouver Island, Nanaimo, B.C.), under the supervision of Professor Tim Stokes. During the visit, the daily temperature was 8 ℃ and the sky was cloudy. The goal of the field trip was to better understand the geothermal energy system named the GeoExchange at Vancouver Island University. Climate change brought up by anthropogenic emissions of greenhouse gases increases the average global temperature on Earth by 1.1 ℃ since 1880, according to the Goddard Institute for Space Studies (GISTEMP Team, 2024). Switching to clean sources of energy, such as wind and solar, is not only a way to reduce anthropogenic emissions of greenhouse gases, but also a way to reduce air pollution and improve our health. Prior to the visit Professor Stokes gave a short overview of the GeoExchange system to the class. During the visit field notes with observations about characteristics of the GeoExchange were collected. 

Background

Figure 1. Geoexchange energy system map (Vancouver Island University, Nanaimo, B.C).

The first borehole (exploratory borehole) was drilled in 2010 (IW‐2) to a depth of 164 m, and a delivery rate of 31 l/sec was produced. Pump testing of this 2010 borehole noted a change of the water level of an observation level near NDS track, confirming that an open underground flow link existed in the abandoned mine workings. Water samples taken from the well indicated that this water was of poor quality and potentially corrosive (high TDS, high in metals and ions, high in bacterias and highly alkaline).

The Geoexchange energy system at Vancouver Island University is located at the Geo-Exchange Building (HSC1 on the map in Figure 1), and relies on water trapped underground in the abandoned Wakesiah mine, it supplies heat to the University’s buildings in coolest months and air conditioning in warmest months.

The GeoExchange energy system was completed in 2018 and relies on mine water at average year‐round temperature from the abandoned Wakesiah Colliery coal mine. This mine water is below most campus at depths of 134‐190 m and the system uses a mine water loop to extract water from one hole (PW‐1). Then the water is put through a heat exchange system in a pump house, where the cooled water is returned into an injection borehole (IW‐1 or 1W‐2). A second ambient water loop takes warm water from heat exchange system at the pump house and transport it to Health & Science buildings where it is used to heat or cool them, after which it is returned to the pump house.

Energy needs for the Health & Science buildings are 95kWh/m² for heating and 57kWh/m²
for cooling. The GeoExchange system reduce energy needs for the Health & Science buildings by 75%. For every unit of electrical energy used to run system it produces
approximately four equivalent units of heat. Estimated energy saving of $66,000 per year compared to equivalent use of gas for heating, is produced with the GeoExchange system.

Figure 2. Water well producing the north mine water at Vancouver Island University (Nanaimo, B.C.).

Notes and Observations

The geo-exchange relies on groundwater trapped in the old Wakesiah coal mine transported all the way from a well located on the north side of the campus (see Figure 2) to the heat exchanger in the Geo-Exchanged building. The system uses its ambient temperature loop to store heat from buildings into cooler groundwater (in the summer), and extracts the heat the warmer groundwater (in the winter) to warm the Health & Science buildings. At full capacity the system can extract water at an average rate of 15L/s and during the tour (on April 8th, 2024), Falcon Engineering engineers were testing the GeoExchange system at full capacity (see Figure 3).

Figure 3. Engineers working hard and testing the GeoExchange system at its full capacity.

Conclusion and Recommendations

The GeoExchange system at Vancouver Island University is dependant on the void spaces left by coal mining underneath the University, and in this regard geoscientists were essential in ensuring the safety and feasibility of such project. Geoscientists helped engineers by providing key geological information about the geological subsurface, allowing for the adequate design and installation of this geothermal system that relies on old mine waters, for both storage and extraction of heat.

References

GISTEMP Team. ( 2024). GISS Surface Temperature Analysis (GISTEMP), version 4: NASA Goddard Institute for Space Studies. Retrieved from https://data.giss.nasa.gov/gistemp/.

March 27th, 2024

Introduction

On March 27th, 2024 students from the Environmental Geology class at Vancouver Island University visited Huddlestone Beach (Lantzville) as well as Piper’s Lagoon Park (Nanaimo), on Vancouver Island (B.C.), under the supervision of Professor Tim Stokes. During the visit, the daily temperature was 6 ℃ and the sky was cloudy with light rain. The goal of the field trip was to better understand the challenges of living in this region, specifically the issue of shoreline erosion and its protection. Climate change disturbs the global mean sea level by adding volume of water to the oceans in two ways, through the melting of ice sheets and glaciers, and by warming the water temperature leading to its expansion. Prior to the visit an investigation of both sites was completed using Google Earth, the Landowners Guide to Protecting Shoreline Ecosystems and Green Shores for Homes (Credit & Rating System, 2015), Passivhaus (An Introduction, 2012), and Green Building in Canada. During the visit field notes with observations about material types, shoreline protection measures, and Green Building construction characteristics were collected. 

Background

In Nanaimo, climate change brings higher temperatures, wetter winters, and drier summers. In 2022, the City of Nanaimo Council adopted City Plan, which is a plan with a number of policies to help support the City adapt to Climate Change. Climate change adaptation strategies can be found throughout City Plan and included two new Development Permit Areas for Sea Level Rise and Wildfire Mitigation to help guide and protect new development from future climate hazards. A development permit (DP) allows City staff to review proposed developments to ensure they meet the policies and objectives of the Official Community Plan as well as the City’s environmental, heritage, and design guidelines. There are nine Development Permit Areas in the City, which serve various purposes including: the protecting the natural environment, ensuring that development considers hazardous site conditions, and ensuring the form and character of development follows relevant design guidelines (The City of Nanaimo, 2023).

In 2018, the Province of BC adopted an amendment to the Flood Hazard Area Land Use Management Guidelines that incorporated new building standards for coastal areas that consider relative sea level rise (RSLR) to 1.0 metre by 2100. The City’s Sea Level Rise Study (Study) was completed in 2019 and is a high-level vulnerability assessment of the City’s coastline. This Study includes sea level rise projections for 2050 and 2100; an assessment of potential coastal erosion impacts and defines a Flood Construction Level (FCL) along the City’s shoreline for 2050 and 2100. Results from this Study indicated that low-lying areas along the coastline are vulnerable to sea level rise, and specifically Departure Bay, Duke Point, Protection Island, and portions of the Downtown (The City of Nanaimo, 2023).

The restoration of a Property’s riparian area was completed in 2020 for shoreline stabilization and erosion control. The property lies on shoreline adjacent to the City of Nanaimo Piper’s Lagoon Waterfront Park, located in the NE part of Nanaimo. Shack Island lies just offshore of this property and provides shelter from the prevailing winds off the Strait of Georgia. Unique patterns of ocean current and abundant use of the foreshore by waterfowl also characterize this site. The low bank beach is gently sloped with sand and cobble-sized material. The overall site is within an intact Garry Oak ecosystem, and the property includes some Garry Oak trees recognized as Significant Trees under the City of Nanaimo’s Management and Protection of Trees Bylaw 2013 (No. 7126) (preserved during the development). The main objective of the project was to remove the bulkhead and restore the foreshore with natural materials and native vegetation to stabilize against erosion and create shoreline habitat. The restoration project removed a concrete bulkhead with a wooden fence attached to the top and a previously used septic system. The entire riparian area was regraded using existing beach materials and tidal function was fully restored through removal of the bulkhead. Large woody material was retained, and small boulders and new stumps and logs were placed higher on the slope to protect the shore through dissipation of wave energy (The Stewardship Centre for British Columbia, 2021).

Notes and Observations

The material type at Huddlestone Beach (Lantzville) is cobbly sand. Evidence of shoreline erosion due to wave energy paired with unconsolidated sediments can be observed. The shoreline shows signs of sediments loss (especially at the base of the scarp) and a beach scarp at height of about 0.80-0.40 m is observed. Signs of erosion are apparent at the base of an old concrete wall, a riprap, and a pile of coal waste materials through materials loss. The old concrete wall is made of concrete embedded with rounded cobbles (height is about 1.2 m) and is eroded at the contact between the level of the tidal waves and the shoreline (erosion height about 0.30 m). A recently installed 0.80 m high and 100 m long concrete wall is installed eastward of the beach. The concrete wall has drainage installed (at 0.50 m in height) and suggests that the high tide line is about 0.25 m. The beach has some cobbly sand with mostly rounded cobbles, some coal and large logs deposited almost parallel to the shoreline. A lot built on coal waste piles has the most severe signs of erosion, and some concrete “pillows” are attached with rods to the shoreline (at 0.10 m in height).

Aspects of Green Building constructions incorporated at the Eby road property are the planting of vegetation on the beach scarp, and the installation of large wood logs on the beach to mitigate erosion and promote ecological resilience. Additionally, hard stabilization methods such as a riprap, concrete walls and concrete “pillows” with rods are used to decrease erosion of the shoreline.

Figure 1. The 100 m concrete bulkhead with drainage systems eastward of Huddlestone Beach.

Figure 2. A trio of passionated young students easily impressed by beach sediments.

Conclusion and Recommendations

All things considered, the best method to mitigate shoreline erosion is the restoration of the beach riparian area to its “natural” state paired with a concrete bulkhead at the beach scarp with a drainage system, and logs on the beach. This would increase resilience to storm events, provide habitat to ecosystems, reduce erosion, and moderate wave action. The concrete bulkhead has a long lifespan and requires simple repair, and the restoration lower environmental impact at the shoreline.  Depending on the future rate of sea level rise, building a seawall to prevent the impact of storm surge flooding and floods might be necessary but its trading off the intertidal zone for infrastructures safety.

References

March 13th 2024

Introduction

On March 6th 2024, students from the Environmental Geology class at Vancouver Island University visited the Regional District of Nanaimo Landfill, in Nanaimo (B.C.). During the visit, the daily temperature was 7 ℃ and the sky was cloudy. The goal of the field trip was to better understand the management and operations of the landfill, to better understand about the processing of solid wastes. The group was supervised by Professor Tim Stokes, and an environmental technician at the Nanaimo Landfill named Chad facilitated the visit at the site.

Background

The Regional District of Nanaimo (RDN) provides regional governance and services to more than 155,000 people on Vancouver Island’s central east coast. In the next ten years, the population is expected to quadruple. The RDN covers a 207, 000 hectares with communities that include the municipalities of Nanaimo, Lantzville, Parksville, and Qualicum Beach, as well as seven unincorporated Electoral Areas (Regional District of Nanaimo, 2024).

There is a requirement by the Provincial Environmental Management Act to develop a Plan — a long-term vision — that defines how the regional district manage its solid waste, including waste diversion and disposal. The RDN got its first plan in 1988, with updates in 1996 and 2004, and has tracked its waste disposal since the 1980s. Since then, residents have reduced, recycled, diverted and composted their waste by more than 68% that was otherwise destined to landfill (Regional District of Nanaimo, 2024).

The new target of the Regional Solid Waste Management Plan (SWMP) is to keep 90% of waste out of the landfill by 2029. This target equal to the average person throwing away 109 kg of garbage per year,  and currently the average residents are throwing away about one-third of what they were in the 1980s — 347 kg/capita/year in 2014 compared to 1,084 kg/capita per year from 1980s (Regional District of Nanaimo, 2024).

Notes and Observations

At the landfill, the first processing step is separation of the waste to appropriate landfill cells, and wood crushing. Machinery removes metal from the waste piles and metals such as steel is sent to private companies for further processing. Garbages going into the landfill cells are covered up by steel plates and dirts, and legally the slopes of the garbage piles needs to stay at a slope of 3 to 1 with 58 m of maximum elevation above sea level. Once the waste cells have been crushed to an acceptable slope and covered up, plastic black tarps are installed on them.

The Nanaimo Landfill is affected by a temperate climate with rainy winter, with large quantity of mud interacting with the waste cells and greater production of methane (CH₄) in comparison to drier climates. Below the landfill there are abandoned coal mines, and some are filled with decades old waste materials. The most negative wildlife interaction with the wastes are seagulls, to counter this problem bear bangers, cracking noises and prey birds are used.

Figure 1. A brave student getting close to an hawk.

The waste produces 40% of CO₂ and 60% of CH₄, and CH₄ flaring takes place at the landfill to reduce greenhouse gases emission. Methane (CH₄) is 86 times more potent in comparison to CO₂, and flaring reduce its potency into the atmosphere, by burning it to produce CO₂ instead. Fortis is interested into using those gases to produce power energy but at this time those are not used to generate power. To collect the gases, vertical and horizontal wells are installed into the waste cells. Wells are filled with clay to create a buffer and avoid interaction with O₂, and some of those have a pump to draw the leachates out of the wells to reduce soils and water contamination.

Figure 2. Students listening eagerly during the bus tour of the landfill.

Conclusion and Recommendations

To increase the space capacity of the landfill, trial shredding and compacting of waste materials is currently being done, so far a reduction in volume of 10% to 20% is observed. Garbage shredders are expensive (millions of dollars) which is to be taken into consideration if choosing to incorporate this technique to process wastes, on a long term basis. The population served by the Nanaimo Landfill is likely to increase, and the public must be better educated about the recycling of plastic and microfibre to further reduce the quantity of wastes, for the region.

References

Regional District of Nanaimo. (2024). Regional solid waste management plan (SWMP). Retrieved from https://www.nanaimo.ca/city-services/garbage-recycling/zero-waste-initiatives/regional-solid-waste-management

March 6th, 2024

Introduction

On March 6th 2024, students from the Environmental Geology class at Vancouver Island University visited a parcel of land at 2229 Boxwood Road, in Nanaimo (B.C), with the goal of collecting observations to complete a Phase I environmental assessment report . During the fieldwork portion of the project, the daily temperature was 4 ℃ and cloudy . The group was supervised by Professor Tim Stokes and environmental scientist Roxanne Croxall (employed by Tetra Tech Canada Inc.) to learn more about restoration activities undertaken at the location. Two days before this field trip, on March 4th 2024, Roxanne Croxall gave a short presentation about the purpose of environmental assessment report to the Environmental Geology class. On that day, the class was split in groups and each of those completed part of a Phase I Environmental Assessment template for the 2229 Boxwood Road location by doing online research and interviewing Roxanne.

This project is an introduction to Phase I Environmental Site Assessments (ESAs) which is a relatively standard environmental practice in BC when examining sites that may or may not have contamination issues and/or have been identified for development. Those reports are a starting point for any contaminated site investigation which is a historical data gathering process and includes a brief reconnaissance field visit. Usually those reports determine the next stages to plan remediation future activities.

Background

The regional topography where the property is located, slopes gently downward to the northwest. Precipitation obtained from Environment Canada for the period 1981 through 2010, using Nanaimo City Yard station, recorded averages annual rainfall of 1099.6 mm, annual snowfall of 40.7 cm, and annual precipitation of 1140.4 mm. The soil geology of the property area consists of sand fill, gravelly, with some mine waste inclusions. The detailed well records obtained described the soils in the area of the property to contain greater than 20% cobbles, 25 cm of stones at the surface, and coarse fragments content ( 20 to 50%). The soil is capped by less than 50 cm of loamy textured material, imperfectly drained, has weakly cemented horizons and is limited by low nutrients content and low water-holding capacity.

The property does not have an aquifer directly below its surface, and also has no surface water bodies. However, aquifers 167 and 211 can be located to the southwest of the property. Aquifer 167 is a confined sand and gravel unit of glacial origin, most likely set in Quadra Sand. It has low vulnerability, and its well density has moderate productivity rates. Aquifer 167 overlies aquifer 211 which is set within fractured Triassic basalts. Should there be contamination at the property, aquifer 211 is at higher risk than aquifer 167 based on its limited catchment zone, low productivity, and higher well density. The possibility of the property to contaminate aquifer 211 should be taken seriously, as this aquifer contains 388 wells.

Local groundwater flow is inferred to flow to the East following local topography towards East. Subsurface structures, such as catch basins, drainage systems, and underground service trenches in the area may influence the local groundwater flow direction. Activities on sites located upstream of the property have the potential to contaminate the sediments of water bodies that cross through or are adjacent to it. Additionally, contaminants may be transported to the water bodies by overland surface flow and groundwater infiltration. If contaminants enter the system, it could negatively impact the soil and its vapour, the groundwater, and/or its sediments. The nearest surface water body is approximately 337m southeast of the property.

Notes and Observations

At the property construction debris overlies mine waste which is mainly coal waste. Mine waste is the discarded rock overburden during previous coal mining operations and at the site the mine waste volume is 32 000 m³. Soil samples locations were selected using cottonwood as an indicator for soil disturbances. The soil samples were collected from coal waste, and the site tested for heavy metals. The main concern from the results of those samples are high levels of heavy metals such as chromium and arsenic, with the red pink shale having the greatest concentration of arsenic. Additionally, iron, manganese and lithium were found in groundwater (at high concentrations all of those can have negative health impact on humans).

A performance verification recommend a cap of 1 meter of uncontaminated soil on the hills of the site. The forest on the property needs a permit to cut more trees, groundwater wells cannot be installed, restrictions on garden is recommended and residential drinking water is safe where the site is excavated. A shaft capped with concrete and a grid from previous coal mining is located on the property. Dry cleaning products were previously dumped on the property, the site is a former coal mine site, and along with coal mining wastes the site has construction wastes such as pipes. The location of the old lake and two mine portals have a high likelihood of containing mine and construction wastes.

Figure 1. Mine waste at the property.

Conclusion and Recommendations

Further testing for leaching and chemicals contaminants of the coal waste is recommended to determine the next stage of remediation of the property. This will need to be remediated by digging out and removing the stockpiles of coal. Any large construction debris will need to be removed and disposed at regulated facilities.  Any areas that cannot be cleaned up will have strict regulations for usage so that the contamination does not impact residential areas. Chemicals that are of major concern are high levels of arsenic, chromium, lead, mercury, benzene, and cadmium. Contaminated soil will need to be removed from future development sites and the area will need to be capped with 1 m of uncontaminated soil. Soils with light potential for contamination must never be used to access drinking water or growing vegetables. Consistent monitoring of water and soil must be conducted to reduce leaching from the waste.

            

February 28th, 2024

Introduction

On February 28th 2024, students from the Environmental Geology class at Vancouver Island University, examined the Departure Bay Creek in Nanaimo. During the fieldwork portion of the project, the daily temperature was 9 ℃ with rainy weather. The group was supervised by Professor Tim Stokes and met with members of the British Columbia Conservation Foundation to learn more about restoration activities undertaken at the Creek. The BCCF is a charitable not-for-profit society developed with the goal of managing and administrating conservation projects in partnership with various funders. Additionally, the BCCF is supporting the efforts of local conservation organizations in their efforts to enhance and conserve fish and wildlife populations. The students collected information from the speakers and collected observations in their field notebooks, to try to answer the following questions:

• What the stream and area were like 1000 years, 200 years, 100 years and 50 years ago? 
• What disturbances have happened to the stream over time? 
• What type of techniques are being used to restore the stream and its habitat? 
• Why is this being done? 
• How can environmental geoscientists contribute to this project?

Background

Departure Bay began to be developed in the late 1800’s with construction of a coal railway/pier system to deliver coal from the Wellington mines to the ships in Departure Bay. The existing development construction started in 1958 with Centennial Park and ended in 1969 with the parking lot and seawall construction along the foreshore. Previous urban stream surveys were funded by the Habitat Conservation Fund in 1993 (Toth) and updated in 2000 through Project 2000 (ATC). Stream restoration work on Departure Creek was done in 1995 and 1996 by Trout Unlimited, Malaspina University College, and local groups. In 2000 the Nanaimo Area Land Trust conducted riparian planting and the Departure Bay Neighbourhood Association completed instream restoration work in 2008. The Harbour City River Stewards continued this work into 2014. Vancouver Island University has conducted water quality analysis in the watershed periodically since 2006. The Community Watershed Monitoring Network has conducted water quality analysis since 2012 (D.R. Clough Consulting, 2016).

The Departure Creek is a small (3.2km²) second order tributary located entirely within the City of Nanaimo. It is approximately 3 km long originating from the Nanaimo Golf Club area
before reaching Departure Bay. The watershed’s main channel flows west to east which is fed by two main tributaries that flow from the north and south. Currently the tributaries (Joseph and Keighly Creeks) offer extremely limited fish access/habitat due to barrier culverts at their confluences (D.R. Clough Consulting, 2016).

The watershed is located in the Coastal Douglas Fir moist maritime (CDFmm) Biogeoclimatic zone (MWLAP 1998) at a median elevation of 70m, in the rain-shadow of Vancouver Island. This climate allows for a diverse group of plants and animals found nowhere else in the country (Madrone 2008). The Creek watershed being severely developed with only the mid reach remaining in a relatively natural state with a functional 2nd growth riparian zone which is greater than 10m wide. The lowest 400m has
been channelized and features a storm water flood diversion. The creek enters the ocean on the north corner of Departure Bay featuring a 2.0 km long gravel and sand beach (D.R. Clough Consulting, 2016).

The North of Departure Bay Creek’s watershed is composed by the Karmutsen Formation (massive and pillowed basaltic flows, breccia), with the Haslam Formation (siltstone with interbedded sandstone, silty shale) to the northwest. The south side of the Creek is composed by the Haslam Formation, the East Wellington Formation ( sandstone, minor gritstone and siltstone), and the Northfield Member (siltstone, carbonaceous shale and coal, lenses of conglomerates and sandstone).

Notes and Observations

The goal of the restoration effort is to return the chum salmons and the coastal cutthroat trouts to the stream. Problems encountered at the Creek that affect fish survival: warm water > 20°C (can cause death), too much sedimentation (fish eggs cannot survive), pollution, and the presence of GPPQE (toxic rubber materials typically from tires on the road) becoming GPPOQ (from friction and UV it becomes toxic) in the stream water. Change of land uses overtime can also changes the water flows between faults, basalt and non-sedimentary beds, reducing the soil cover and ground absorption of water (increasing the velocity of water infiltration to runoff in the Creek and increasing bank erosion), and a greater discharge from the Creek to the ocean means that there is less water available in the Creek during drought (lower water table). The Creek is surrounded by invasive plants species such as the English Ivy, and the black squirrels are eating the bark of trees.

Manmade structures to redirect water flows were built such as the installation of a riprap (permanent layer of large stones to armor, stabilize, and protect the soil surface against erosion and scour in areas of concentrated flow or wave energy) in the Departure Bay Creek. Death trees were added to the Creek to create habitats for the fishes (creating shelter and shade).

Conclusion and Recommendations

The stream water level is lower than it used to be, this decrease in discharge means that the fishes cannot always reach the Creek because it can be dry during drought. The main causes of this disturbance is urban development in the area (change to land uses), which increased the rate of erosion of its banks and reduced its soil cover. From those changes, when heavy rainfall events occur, it creates torrential water in the Creek where the fishes are knocked down into the ocean which reduce their capacity to survive (less refuge). The Creek had a riprap installed, with trees added to the stream to create shelter for the fishes. Additionally, a vegetated riparian buffer was re-established with 100 native trees including Red Alder, Douglas Fir, Giant Sequoia and Big Leaf Maple, as well as a wide range of native shrubs and plants. An instream pool and riffle habitat has also been created along with large woody debris. This provides cover for fish and helps to maintain the streambed (City of Nanaimo, 2024). Future anticipated problems in the Creek could be brought on by climate change which could potentially increases the temperature of the Creek’s water (changing its pH and increasing water acidity) further reducing their chances of survival.

References

City of Nanaimo. (2024). Green initiatives; re: established. Retrieved from https://www.nanaimo.ca/green-initiatives/natural-environment-and-ecosystems/ecosystems/re-established

D.R. Clough Consulting. (2016). Departure Creek habitat assessment report. Retrieved from https://www.rdn.bc.ca/sites/default/files/inline-files/Departure%20Creek%20Habitat%20Assessement%202016.pdf

February 7th, 2024

Introduction

Under the supervision of Professor Tim Stokes, on February 7th 2024, students from the Environmental Geology class at Vancouver Island University examined slope stability issues at Sealand Park in North Nanaimo. During the fieldwork portion of the project, the daily temperature was 8 ℃ with a partly sunny sky. Groups of two to three students were formed with the goal to document relevant observations at sites of past or active landslides. Each group collected their own observations and developed a preliminary slope stability hazard map of the Sealand Gully and part of the shoreline. Features were located on topographic and LiDAR maps, placemark were saved in Avenza Maps (using a geo-referenced map) at each site of interest within the gully, soil samples were collected, and all observations documented into a field notebook. Once the fieldwork was completed the team developed a simple hazard map of Sealand Gully and part of its shoreline. Additionally, a simple risk analysis of the site accounting for potential impact to structures and properties was completed. The purpose of this field trip was to examine the possible causes of the landslides at Sealand Park, to identify sites with higher risk of future failures and better understand their impacts to infrastructures. 

Background

Vancouver Island has an extensive glacial history with records of glaciation dating back to 194,000 years ago during the Penultimate. The latest glaciation is that of the Wisconsinian that occurred approximately 75,000 years ago. The Wisconsin Glaciation deposited a variety of sedimentary deposits including but not limited to glacial, glaciofluvial, lacustrine, and marine. These are defined lithostratigraphic deposits based on the means and climatic conditions in which they were deposited. 

 Sealand Park possessed thick deposits (tens of meter) consisting of Cowichan Head, Quadra Sand, Vashon drift and Capilano Sediments, and is situated within an existing gully that no longer possess an active stream channel and has been altered to such an extent that it is no longer viable for fish habitation. At the base of the gully an artificial pathway was constructed. The gully is exclusively cut through glacial material from the past flow path of the stream with the banks often presenting severe angles of repose. This degree is common given the composition of the deposits. Bedrock is not observable at the surface. The north-west extent of the park transitions into a high energy intertidal zone based on the large sized and well-rounded cobbles and boulders. 

Notes and Observations

Table 1. Field Observations at Each Site at Sealand Park Gully.

Site #	Dimensions	Slope	Slope Geometry	Volume of Debris Pile	Comments
1	Displaced Materials: ≈30 m length ✕ ≈4 m width ✕ ≈2 m thickSlope Length: ≈30 mHead Scarp Height: ≈20 m	42°	Concave	≈ 240㎥	Shallow translation/ Earth fall/ Sparsely vegetated by ferns/J-hooked treesVashon drift underlain by Quadra sands.
2	Displaced Materials: ≈20 m length ✕ ≈10 m width ✕ ≈5 m thickSlope Length: ≈20 mHead Scarp Height: ≈50 m	42°	Concave	≈ 1000㎥	Aged slump/  Middle-aged forest/ Slope sparsely vegetated with ferns/ J-hooked trees/ Overhang & head scarp with fresh fall to left/ Irregular slump.
3	Displaced Materials: ≈30 m length ✕ ≈60 m width ✕ ≈5 m thickSlope Length: ≈ 30 mHead Scarp Height: ≈38 m	32°	Concave	≈ 9000㎥	Middle-aged forest with dense floor cover/ Irregular slope/ Unidentifiable failure mechanism due to vegetation/ Debris pile sparsely vegetated with ferns/ Head scarp inwards.
4	Displaced Materials: ≈ 30 m length ✕ ≈ 60 m width ✕ ≈  5 m thickSlope Length: ≈ 30 mHead Scarp Height: ≈ 17 m	31°	Concave	≈  9000㎥	Earth fall/ Creep/ Possibly shallow translational/ Sparsely vegetated with ferns & middle-aged trees / Initial runout flat and regular that follows into irregular runout/ Middle-aged forest/ 40 horizontal  / J-hooked trees at different directions/  Vertical head wall made of clay rich Vashon Drift(?)
5	Displaced Materials: ≈ 30 m length ✕ ≈ 20 m width ✕ ≈ 5 m thickSlope Length: ≈ 30 mHead Scarp Height: ≈ 40 m	43°	Concave	≈ 3000㎥	Middle-aged forest with  mature tree growth & sparsely vegetated ferns/ J-hooked trees/ Creep/ Irregular slope / Earth fall?/ Debris pile has regrowth on top/ Narrower comparatively
6	Displaced Materials: ≈ 15 m length ✕ ≈ 20 m width ✕ ≈ 5 m thickSlope Length: ≈ 15 mHead Scarp Height: ≈ 100 m	28°	Concave	≈ 1500㎥	Vashon drift/ J-hooked trees/  Earth flow? Creep?/ Head wall with gradient Curved head scarp/ Fresh runout over vegetation / House up above on head wall/ Middle-aged forest & sparsely vegetated with ferns/ Regrowth on debris pile
7	Displaced Materials: ≈ 30 m length ✕ ≈ 3 m  width ✕ ≈ 3 m thickSlope Length: ≈ 30 mHead Scarp Height: ≈ 10 m	28°	Concave	≈ 270㎥	Overhanging head scarp (vertical) of Vashon drift (lenses and till)/ Runout irregular with recent colluvium and dead vegetation/ J-hooked trees/ Silt layer/ Regrowth on debris pile (middle-aged forest)/ Earthfall?Vashon Drift (lenses and till), silt layer within till
8	Displaced Materials: ≈ 15 m length ✕ ≈ 30 m width ✕ ≈ 3 m thickSlope Length: ≈ 15 mHead Scarp Height: ≈ 20 m	40°	Concave	≈ 1350㎥	Earth flow /Debris flow fall with active creep and water flow on clay rich till(?)/  No observable head scarp/  Linear flow/ No translation/ Slight bowl shape/ Debris pile with regrowth (middle-aged forest)/ Sparsely vegetated with ferns/ J-hooked trees

Table 2: Slope Stability Hazard Rating.

Slope Stability Hazard Rating	Hazard Rating Probability/Likelihood	Descriptions of Slope Conditions
High	Probability of slope failure is eminent, and the magnitude could be considerable.	Evidence of natural landslide occurrence with a slope angle equal to or greater than 30 degrees. Urban development is within direct runout zone or proximal to head scarp.
Moderate	The probability of slope failure resulting in considerable mass movement of urban disturbance is not expectedwithin predictable parameters*, however, regular inspection is recommended.	Slope angle less than 30 degrees. Urban development is within vicinity. Poor to well-drained soils. Moderate gullying. Increased erosion expected following drainage disturbance. Water courses could cause higher potential of bank slumping.
Low	Probability of slope failure is unlikely, and magnitude is low unless extraneous conditions arise.	Slope angle is within 0 to 15 degrees. Poor to well drained soils. Minor slumping following ground disturbance

Sealand Park Slope Stability Hazard Map

Figure 1. Sealand Park Slope Stability Hazard map, built by Fanny Deschenes and Aiden Kilcommons.

Conclusion and Recommendations

 Risk analysis is based on in-situ site analysis, air photo interpretation, satellite imagery (Google Earth) in concordance with the existing knowledge and experience of the semi-qualified terrain specialists.  

Within the area of interest (AOI) recent landslides are present providing an indication for the likelihood and magnitude of a subsequent mass wasting event. Air photos and satellite imagery provide comparison of historic conditions to present day. Knowledge and experience of terrain specialists can capture information from the former qualitative attributes to develop a rational for the terrain hazard rating.  From the risk analysis completed at Sealand park, the following recommendations are proposed:

• Avoid undercutting steep slopes.
• No building near those slopes (base and top).
• Do not fill steep slopes.
• Re-vegetation of the gully banks.
• Installation of drainage systems.
• The drainage of large quantity of water should be avoid within the areas (draining pools, etc.)

January 10th, 2024

Introduction

On January 10th 2024, Vancouver Island University students, in the Environmental Geology (GEOL312) class, completed a field trip at Colliery Dam under the supervision of Professor Tim Stokes . The purpose of this field trip was to collect and report on a real-life environmental issue, using information gathered during the visit and available reports. The group met at the parking lot entrance of Colliery Dam (parking located by Lower Dam) with Euan Wilson and Mike Squire. Mike Squire is the Manager of Water Resources for the City of Nanaimo and both Euan and Mike updated the group about recent monitoring and investigations at Colliery Dams. The group walked from the parking lot to the Lower Dam then to Middle Dam, where the group were shown the spillway and the levee installed to help control the release of water downstream. The data collected on the field trip were information provided by both Euan and Mike.

Background

Colliery Dam was built in 1910-11 by the Western Fuel Company to supply water for coal washing. The Middle Dam show an exposure of sandstone and Colliery Dams is underlain by the Nanaimo Group deposits. The Colliery Dams park included forested areas, waterfalls, bridges and streams.

Colliery Dam Park is a popular destination for summer freshwater swimming and is home to three dams with high to very high risk of failure. Should the dams failed, the most important risk is from a seismically induced dam failure, likely to result in significant risk to downstream areas from the impounded volume of water upstream of the Lower and Middle Dams. Currently both structures (Lower and Middle Dams) are classified as Very High Consequence, due to population locate in the downstream floodplain areas and neither of those dam meeting the expected level of performance for flood or seismic safety, where both considered to be a level of risk outside the acceptable risk using generally applied standards (EBA, 2010). Possible consequences of the dams failure are loss of human life and their pets, destruction of residential and public structures, destruction of ecosystems on the floodplain and their species, and damage in the range of 40 millions dollars (Associated Engineering, 2012).

Notes and Observations

WMC’s investigation indicated that both the Middle and Lower Dams spillways have inadequate capacity either for the PMF or 1000-year return period event, with overtopping of the dam crests likely. Also, the Lower Dam spillway has inadequate capacity for the 100-year event, but the Middle Dam spillway have adequate capacity for the 100-year return period flood event. Induced failures are possible and the studied possibilities are: a 100-year return period flood event (overtopping failure of the Lower Dam only), 1000-year return period flood event (overtopping failure of both the Middle and Lower Dams in a cascade sequence (Middle Dam fails first leading to the immediate failure of the Lower Dam) with both the Middle and Lower Dams breach hydrographic peaks assumed to coincide, and finally a PMF event (overtopping failure of both dams in a cascade sequence where the Middle Dam fails first leading to immediate failure of the Lower Dam) and both the Middle and Lower Dams breach assumed to coincide. Overall, if the Middle Dam fails first it will result in a cascade failure of the Lower Dam (Associated Engineering, 2012).

A 100-year return period seismic event is estimated to result in a higher number of causalities than the Probable Maximum Flood (PMF) which has an approximately probability of a 10,000-year return period event. The dams high risk hazard assessment  is based on the results of the 2012 Chase River Dam Breach Flood Inundation Study. Both the Middle and Lower Chase River Dams were constructed circa 1910/1911, making them 100 years old. The construction practices of that period are one of the major factors in the degree of concern regarding the safety of those Dams from both a seismic and flood risk perspective. All those Dams are composed of an internal concrete core, with a shell of fill material placed on either side of the core. EBA’s “Seismic Hazard Assessment Middle and Lower Chase Dams” of April 2010 provides the dam’s construction details, including uncertainties regarding ,and probable elements of their construction are: the concrete cores are almost certainly unreinforced with their construction quality poor in nature (compared to current practices), the concrete is potentially honeycombed and its core walls are known to contain cold joints, original fill materials were end dumped and hand placed ( no mechanical compaction), likely lenses of coarse and fine material in the original dam fills,
both dams had wood stave low level outlets penetrating the fills and concrete
cores, over time the wood stave conduits would rot (increase possibility of seepage failure) (Associated Engineering, 2012).

Conclusion and Recommendations

To mitigate the risk, in 1980, the City undertook significant work on both dams to address the low level outlets, where the valve chamber and low level outlets on the Lower Dam were filled with concrete, eliminating this source of concern on the Lower Dam (the low level outlet was not successfully located on the outside face of the Middle Dam), the lower shell on the Middle Dam was replaced with compacted fill composed of pit run sand and gravel (replacing the questionable original fill material, except on the left abutment (looking downstream) (Associated Engineering, 2012).

There is a 40% chance during a 50-year period that the dams will fail as a result of a seismic event and that damages would be in the range of $40 million (2012 dollars). The floodplain has many buildings including schools, family residential homes, a large school, a daycare, apartment, and commercial buildings. The flood zone also contains major transportation corridors including Highway 1 and the E&N Railway, and an estimated population (based on the 2011 census data) of 1883 inhabitants (Associated Engineering, 2012).

Euan and Mike, stated that the options available to reduce the risk at Colliery Dams is either to remove the dams or invest to rebuilt sections of the dams with modern construction method taking into consideration climate change. Unfortunately, according to both of them, the council voted against improving Colliery Dams to reduce the risk.

References

Associated Engineering. (2012). Chase River Dam Breach Flood Inundation Study. Retrieved from https://www.nanaimo.ca/docs/your-government/projects/2015-colliery/report-37.pdf

January 18th, 2024

Earth can be thought as a large ecosystem in which many different ecosystems with communities of living organisms are living and interacting together in a specific environment. Usually, ecosystems are in a state of stability, but can be subjected to changes from which they recover back to ecological balances. When the ability of the ecosystem to sustain its associated species is destroyed, the ecosystem is said to have collapsed. Sometimes, ecosystem collapses are caused by environmental problems where the system ecological function is destroyed due to human activities.

One environmental issue that put pressure on all ecosystems on Earth is climate change. The shift in climates is disrupting the species capacity to adapt and survive in their ecosystems, by changing rainfall and air temperature in those systems. Pollution, resources depletion, environmental degradation, deforestation, and waste management are other environmental issues that have the strong potential to destroy ecosystems. 

By virtue of their multiples dimensions, environmental problems are complex problems to solve. Some ecosystems are more sensitive to changes in comparison to other, the pressure on the system can be from more than one source, the sources of environmental issue can interact with each other and have many effects on the system. 

Environmental geology encompasses human populations growth, sustainability, earth as a system, hazardous earth processes, and scientific knowledge. Environmental geology is interested in the geographic and geological composition of the Earth and uses geological principles to better understand the causes and find the most suitable methods for dealing with environmental issues and hazards. Environmental geology can investigate the cause of disasters, find ways to fix its effects and potentially prevent them in the future.