<p> Although successful in laboratory studies, field applications of in situ remediation of chlorinated solvents in groundwater have met with limited success. This is most often attributed to the inability to deliver the amendment evenly throughout the target zone, especially in low permeability and heterogeneous materials. The goal of this research was to employ a prototype of a novel delivery system to evenly deliver amendment across the depth and breadth of the subsurface in a cost-effective method. The research was conducted at 42 Voyager Court, Toronto, ON where concentrations of vinyl chloride in groundwater were in excess of Ontario Ministry of the Environment guidelines (O.Reg.153/04). The subsurface consisted of sandy and clayey silt fill underlain by sandy silt till.</p> <p> The delivery system comprised 29, 1/4" diameter, delivery points with small perforations along the length, installed in a fence perpendicular to groundwater flow, approximately 0.5 m upgradient of the area of concern. The delivery system used low flow rates (approximately 13 to 23% of total
groundwater flow) and discrete delivery holes to deliver a potassium permanganate solution (approximately 40 g/L) amended with sodium bromide (approximately 0.8 g/L) across the depth of the subsurface. Fourteen multi-level monitoring wells, each with five sampling ports were installed to monitor the effectiveness.</p> <p> After six months of delivery, sample results indicated that oxidant demand hindered the ability of potassium permanganate to reach and degrade the vinyl chloride. However, elevated bromide concentrations were detected at all downgradient sampling ports within a 1.5 m distance. Thus, the delivery system was successful at delivering the amendment across the depth and breadth of the
target area and achieving even delivery.</p> <p> Problems, typically leaks, were encountered with the delivery system design. Additional engineering would be required to improve the header system prior to commercializing this process. This would be a beneficial endeavor, as results of this work indicate that this passive delivery fence technique meets a real need in the remediation industry, which is the even distribution of amendment to target zones in the saturated subsurface, including zones of low permeability.</p> / Thesis / Master of Applied Science (MASc)
| Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/21805 |
| Date | January 2006 |
| Creators | Ryter, Erika Anne |
| Contributors | Dickson, S.E., Civil Engineering |
| Source Sets | McMaster University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
Page generated in 0.0025 seconds