PROJETCS

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HDI assumed the role of QP and delivered services for a thorough water management detailed design, providing essential permitting support during the bulk sample phase at Bolivar and Yew Sites. The undertaken responsibilities included conducting a comprehensive site-wide water balance analysis, performing a hydrology baseline study, and designing an array of water management structures. These structures comprised settling ponds, sumps, diversion and collection ditches, check dams, culverts, and infiltration swales. Notably, HDI also conducted a Dam Breach Inundation study focused on the Bolivar Ponds.

 HDI was retained by Zyrox Mining to develop a 3D numerical groundwater (GW) model for the Yew site located at the Texada Mine Project, situated on Texada Island near Powell River, British Columbia with the following objectives: (1) establish a baseline model calibrated to observed data, and (2) create predictive scenarios to evaluate potential impacts under various conditions. The results of this modeling will support environmental assessment (EA) and permitting process regulatory compliance, and operational decision-making 

HDI conducted a comprehensive assessment of sedimentation and erosion conditions within the Milligan Creek watershed, situated at Elk Valley Operations near Sparwood, BC. The assessment involved a detailed evaluation of sedimentation potentials throughout the watershed, employing techniques such as soil sampling, Total Suspended Solids (TSS) and flow measurement, and spatial analysis.

Furthermore, HDI examined the settling capacity of retention ponds distributed across the watershed. This analysis incorporated measurements taken at both inlets and outlets of the ponds, supplemented by 2-D hydraulic modeling of the drainage network.

 HDI was retained by Discovery Silver Corp to complete a Prefeasibility Study (PFS) level surface water management of the facilities at Cordero silver deposit property in northern Mexico, south of Chihuahua state, approximately 600 km from the border with the United States. The deposit lies in a region that has a long history of silver mining dating back to the 1600s. In the hills where the Cordero deposit lies, there are several small mines with rich silver veins that reach the surface. In the past two decades, the possibility of a large bulk mining target at depth at Cordero was explored and tested through drilling carried out by Levon. 

HDI conducted site-wide water balance analysis, watershed analysis, extreme rainfall analysis, development of a rainfall runoff model, design of water management structures such as diversion and collection ditches, collection ponds. The work also involved estimation of total excavation volumes for constructing the water management structures.

HDI conducted a comprehensive engineering assessment and detailed design for Bolivar Dams #1 and #2, ensuring their structural integrity, hydraulic performance, and long-term stability. The scope of work included reviewing historical data, geotechnical investigations, hydrotechnical modeling, and seepage analysis to assess existing conditions and identify potential risks.

As part of the detailed design process, HDI optimized dam geometry, designed spillways for effective flood management, and incorporated erosion control measures to enhance resilience. Additionally, instrumentation plans were developed to monitor dam performance, including piezometers and flow measurement systems.

HDI also provided construction support, ensuring adherence to best practices and regulatory requirements.

 HDI served as a subcontractor to Hatch for the execution of a comprehensive baseline study at the La Loutre property, located 180 km northwest of Montreal, QC. The study involved extensive data collection on climate, meteorology, surface water, groundwater, and water quality through field campaigns and other sources. Flow rates were meticulously estimated at fine temporal intervals, and long-term frequency analysis was conducted to understand patterns.

The team meticulously analyzed water quality sampling results, identifying potential exceedances and determining monthly or seasonal trends. This comprehensive baseline study provided valuable insights into the environmental conditions of the La Loutre property, contributing essential data for informed decision-making and sustainable management practices.

Osisko Mining retained HDI for a Preliminary Economic Assessment (PEA) level surface water management project at the Garrison Gold Property near Matheson, Ontario. Situated approximately 110 km east of Timmins, the Garrison Project encompasses the Garrcon, Jonpol, and 903 zones pits within the Upper Abitibi Watershed in the Garrison Creek watershed area south of Highway 101, draining into Lake Abitibi.

HDI's scope of work included a comprehensive site-wide water balance analysis, watershed analysis, and extreme rainfall analysis. The team developed a rainfall-runoff model and designed essential water management structures, including diversion and collection ditches and collection ponds. Additionally, the project involved estimating total excavation volumes for the construction of these water management structures. This thorough assessment provided valuable insights for effective surface water management at the Garrison Gold Property.

HDI was commissioned by O3 Mining to conduct a Preliminary Economic Assessment (PEA) level surface water management project at the Marban Gold Project near Malartic, Québec. Positioned between the lakes of Malartic and De Montigny and in proximity to Malartic Mine and Val-D’Or, the Marban Gold Project presented unique challenges and opportunities.

The scope of work included a thorough site-wide water balance analysis, watershed analysis, and extreme rainfall analysis. HDI developed a comprehensive rainfall-runoff model and designed crucial water management structures, encompassing diversion and collection ditches, as well as collection ponds. Additionally, the project involved estimating total excavation volumes necessary for the construction of these essential water management structures. This assessment provided crucial insights for effective surface water management at the Marban Gold Project.

As a subcontractor to Ausenco, HDI played a key role in preparing a Snow Management Plan for both the Technical Sampling Phase and the Final Phase at the Eskay mine site. The mine is located approximately 83 km northwest of Stewart, British Columbia, in the Unuk and Iskut River region, with an average elevation of 1,100 meters. Given the region's heavy rainfall and snowfall, averaging 2,500 mm of precipitation annually, of which 55-70% is snow, effective snow management is crucial.

For the Technical Sampling Phase, HDI conducted a detailed watershed analysis and extreme snowfall and snow on the ground frequency analysis. The resulting Snow Management Plan aimed to manage snow and contact water generated from the proposed Technical Sampling and Quarry areas, while also collecting snowmelt process data during the melt season to ensure compliance with Eskay's environmental permits, licenses, and approvals.

In the Final Phase, HDI proposed a conceptual Snow Management Plan to effectively manage snow from the Pit, Plant site, Waste Rock Storage Facilities (WRSF), and Haul Roads, addressing the unique challenges posed by the Eskay mine site's environmental conditions.

Canadian Pacific Railway (CP), in response to environmental impacts from the Vancouver Intermodal Facility (VIF), has initiated a restoration project for a semi-functional marsh near Pitt River. HDI conducted a study on the hydrologic and ecologic aspects of this tidal marsh in Addington Point. The study included statistical analysis of historical tide and river water levels. The offsetting design involved system modifications like dike breaches, a drainage channel system, sediment traps, and side-channel pools. HDI's hydrotechnical team contributed to design, detailed drawings, 2D hydraulic modeling, and a hydrological analysis report. The proposed changes aim to enhance flow complexity and provide habitats for diverse wildlife.

  HDI conducted a comprehensive study to evaluate the hydrologic response to extreme precipitation events, both in existing conditions and post-development. The focus was on stormwater levels in Katzie Slough and their impact on industrial and agricultural lands, considering provincial and federal criteria. The study also assessed the effectiveness of proposed mitigation measures in reducing project impacts compared to pre-development conditions.

The modeling extended to the entire Katzie Drainage area, covering Pitt Meadows and Maple Ridge, BC. It investigated the hydrologic response of the ditch, flapper gate, and pumping system to extreme storm events and tidal waves. The integrated drainage system, comprising three pumping stations, a peripheral dike system, and an urban stormwater management network, was also modeled to evaluate the impact of extreme Fraser River water levels caused by storm and high tidal conditions.

Recommendations, including pump replacements, the use of muted tidal regulators, and Best Management Practices (BMPs), were provided to ensure optimal water flow and enhance the aquatic environment. 

  HDI conducted a comprehensive flood inundation mapping study for Guichon Creek in the aftermath of the November 2021 flood event. This initiative was undertaken in collaboration with the Lower Nicola Indian Band (LNIB), with HDI actively supporting LNIB in successfully securing federal funding for the study.

To ensure accuracy and precision, HDI acquired high-resolution topographic data through LiDAR and bathymetric surveys. Leveraging this data, the team performed hydraulic simulations and spatial analysis to delineate potential inundation scenarios during extreme events. The focus of the study extended to assessing flood-related risks to residents and facilities situated in the lower reaches of the Guichon Creek valley, particularly within the Lower Nicola community.

The outcomes of this study aim to provide valuable insights into the extent and magnitude of potential flooding, aiding in the development of effective strategies to mitigate risks and enhance resilience in the face of future flood events.

   HDI was engaged by WSP to conduct a comprehensive hydraulic analysis for the construction of a pedestrian bridge in Alberta. The analysis involved a detailed 2D full momentum analysis of the bridge, considering both the construction phase and its completion. HDI skillfully modeled the final and temporary diversion structures, with the inclusion of a robust erosion and scour protection design for the project.

HDI collaborated with Woodland Cree Nation  to conduct a thorough flood analysis and mitigation planning for their community in proximity of Woodlands. In response to severe flooding affecting dwellings, roads, and bridges, the project aimed to understand potential flooding scenarios under extreme conditions, including bridge debris blockage and ice jam situations. HDI utilized advanced 2D full momentum and diffusive wave modeling for the analysis pinpointing areas with significant flood vulnerabilities. The outcome included the development of a phased mitigation plan tailored to address Woodland Cree specific needs.

HDI was retained by a private developer in the Sunshine Coast region to design a box culvert intended to facilitate safe and efficient stormwater drainage and maintain stream continuity for aquatic habitats. The scope of HDI's services included site investigation, hydrologic and hydraulic modeling, detailed structural design, and coordination with regulatory agencies to secure the necessary permits and approvals.

The culvert was designed considering local environmental sensitivities, aiming to minimize ecological impacts while supporting future development needs. .

Following the 2022 Atmospheric River event, HDI was retained by private property owners in the Shilshole Bay area to assess the impact of flooding from Puget Sound on their properties and marina. HDI developed detailed flood inundation and hazard mapping, utilizing advanced 2D hydraulic modeling to accurately simulate coastal flooding conditions.

Through comprehensive site reconnaissance over three days, HDI compiled an inventory of vulnerable infrastructure, including houses, marina facilities, docks, and boat launches. The resulting flood maps allowed HDI to categorize each structure based on flood hazard risk, providing clear recommendations for suitable mitigation measures tailored to each property and marina asset.

HDI collaborated with Ausenco to create a baseline monitoring program for Anderson Resorts. Overcoming accessibility challenges, HDI utilized helicopters to access the site, where hydrometric and water quality monitoring stations were established. Winterized stations were set up, and monthly measurements were conducted over the course of a year. Leveraging the collected data, HDI developed associated rating curves and analyzed water quality sampling results. This comprehensive analysis established robust baselines and identified potential exceedances and determined monthly or seasonal trends in water quality.

HDI was commissioned by the Town of Redmond to conduct dam breach modeling for Sammamish Lake and recommend a failure consequence classification for the dam. During a two-day site visit, HDI inventoried potential flood-vulnerable structures in the floodplain. The team developed a BREACH model to determine peak dam breach flow under sunny day and flood-induced failure scenarios as per Canadian Dam Association (CDA) guidelines. This breach flow data was then integrated into a 2D hydraulic model, accounting for all downstream bridges from Haslam Lake.

HDI was engaged by Squamish First Nation to evaluate three significant culverts in  BC. Following a site visit to collect measurements and hydrological data, HDI modeled the three culverts and suggested enhancements considering fish passage and climate change effects. The design drawings for the proposed culverts incorporated erosion protection measures.

  Holsted Aggregates Ltd. (Holsted) is assisting Alberta Transportation and Economic Corridors (ATEC) with proposed development activities at the Little Smoky River No. 7 Gravel Pit (the Project). As part of the development process, Holsted has engaged EDI and Boreal to assist with certain environmental and regulatory aspects of the Project. Included their scope of work is a 1-in-100 year flood inundation assessment, for which they retained HDI to complete 2D flood models and inundation maps. 

 HDI was retained by Zyrox Mining to develop a two-dimensional dam breach model incorporating non-Newtonian viscous flow assumptions. The objective was to assess potential inundation scenarios and determine the dam’s consequence classification. Through a detailed and strategically developed approach—modeling both sunny-day and rainy-day breach scenarios—HDI successfully demonstrated a reduced downstream impact. As a result, the dam’s consequence classification was lowered by one category, leading to significant cost savings and reduced operational requirements for the client.