Base de données de recherche des TNO

étiquettes: contaminants, site remediation, water quality, geotechnical survey, soil chemistry

Objectif(s): To remove and dispose of exposed solid waste (including barrels, batteries, debris, wood, and other waste); and, to construct a contaminated soil and waste containment structure on top of the existing buried waste area.

Description du projet: The objectives of the Site Remediation Program are to: 1) remove and dispose of exposed solid waste (including barrels, batteries, debris, wood, and other waste); and 2) construct a contaminated soil and waste containment structure on top of the existing buried waste area. The proposed 2017 Site activities will include several investigations in support of the remediation program: Thermal Investigation – Two Digital Temperature Cables (with a total of six sensors) will be installed in the containment structure to facilitate remote temperature monitoring at different depth intervals. A background cable may also be installed to record temperatures outside of the containment structure. Confirmatory Soil Sampling - Previously delineated contaminated soil will be excavated from the active layer beyond the footprint of the containment structure and relocated to the containment structure. Confirmatory soil sampling will be performed before excavation areas are filled with clean material. Surface Water Sampling - Background surface water samples will be analyzed prior to commencing 2017 site work in order to establish baseline environmental conditions. Samples will be collected upstream, downstream of the water crossing and from select, nearby water filled depressions. Groundwater Sampling - Four monitoring wells will be installed around the perimeter of the containment structure to analyze groundwater in 2017 and during several post-construction monitoring Site visits as per Inuvialuit Water Board requirements. Background Soil Sampling - Soil sampling locations will be established within a two to four metre radius of each of the monitoring wells - for each location, two samples will be collected (one shallow, one deep) and analyzed. Topographic Survey – A high resolution topographic survey will be conducted at the containment structure and the borrow areas. It will capture the layout of ground control points for the unmanned aerial vehicle (UAV) survey. The survey will also be used to determine the installation of permanent bench marks. The monitoring wells and environmental sample locations will be tied in. UAV Survey Field Program – A low altitude UAV survey of the containment structure, the borrow areas and ground control points will be performed. The planned 2017 project intends to mobilize heavy equipment, materials and supplies, camp components and the field crew through Mould Bay to Satellite Bay to remediate the site. Two temporary camps will be established, one at each site. Remediation will include removing waste and debris currently at the site and constructing a contaminated soil and waste containment structure with a thermal cover at the site. The structure will measure approximately 8,500 m2 plus a 10 m wide buffer zone (resulting in a total of 12,500 m2). The thermal cover will provide a cap on the contaminated material that is sufficiently thick (approximately 2.4 m) to contain estimated seasonal thawing within the cap, thereby ensuring that all buried waste and contaminated soils remain at ground temperatures less than 0°C. The construction will also include the development and short-duration operation of a borrow pit, designed to maintain positive drainage, avoid the creation of water collection points and maintain excavation geometry to facilitate the later grading and re-contouring. The duration of the planned 2017 project (construction portion) will be approximately 8 weeks in July and August. Two temporary camps will be required. One 20-person, temporary camp will first be established at Mould Bay to be used during mobilization and demobilization phases of the project. It is anticipated that this camp will not be utilized during the construction phase. One 24-person temporary camp will then be established at Satellite Bay for approximately 8 to 10 weeks during construction activities. Approximately 22 staff are expected on site at any given time. Clifton will be the General and Principal Contractor coordinating all on-site activities and responsible for health and safety. Golder will be Repsol's primary researcher for all engineering work and associated construction. Repsol will engage various other (sub) contractors to complete the work and associated construction of the containment structure. Repsol will submit a follow-up report to the Hunters and Trappers Committees of Sachs Harbour and Ulukhaktok, the Government of the Northwest Territories Lands Department, Indigenous and Northern Affairs Canada, the Inuvialuit Water Board and the Aurora Research Institute. This will include a plain language summary of investigation findings. The fieldwork for this study will be conducted from June 15, 2017 to September 30, 2017.