Changes

Vulnerability for source water is simply calculated by:  

Vulnerability for source water is simply calculated by:  

# Determining the amount of time it takes for water to travel through the "unsaturated zone" above the water table; and,

# Determining the amount of time it takes for water to travel through the "unsaturated zone" above the water table; and,

# Adding that number to the modelled time it takes for groundwater to flow from the water table to the well based on the WHPA zone.  

# Adding that number to the [http://protectingwater.ca/uploads/Documents/swp03%20-%20Appendix%20B%20-%20Hamilton%20Vulnerability%20Report%20v32-final.pdf modelled time] it takes for groundwater to flow from the water table to the well based on the WHPA zone (EarthFx Incorporated, 2010<ref>Vulnerability Assessment and Scoring of Wellhead Protection Areas - City of Hamilton, Ontario. Published April 2010. Prepared for the City of Hamilton - Public Works Department, Environment and Sustainable Infrastructure Division. http://protectingwater.ca/uploads/Documents/swp03%20-%20Appendix%20B%20-%20Hamilton%20Vulnerability%20Report%20v32-final.pdf</ref>).  

As a result, these surface to well duration periods are categorized as "low" for over 25 years, "medium" for 5 - 25 years, and "high" for 0 - 5 years. These surface to well advection times are categorized as low for over 25 years, medium for 5 to 25 years, and high for 0 to 5 years of travel. After this mapped groundwater vulnerability areas are then overlain on top of current WHPAs A - D to then assign vulnerability scoring between 2 - 10 (lowest - highest vulnerability scores). The location of a potential development site within the WHPA and its vulnerability score are then used to assign the significance of proposed or future potential actions/activities that have been labelled as potential threats to local drinking water sources. These 22 potential threats as laid out by the province can be seen in the table below in this section (Halton-Hamilton Source Protection Region, 2010<ref name="example3" />).

As a result, these surface to well duration periods are categorized as "low" for over 25 years, "medium" for 5 - 25 years, and "high" for 0 - 5 years. These surface to well advection times are categorized as low for over 25 years, medium for 5 to 25 years, and high for 0 to 5 years of travel. After this mapped groundwater vulnerability areas are then overlain on top of current WHPAs A - D to then assign vulnerability scoring between 2 - 10 (lowest - highest vulnerability scores). The location of a potential development site within the WHPA and its vulnerability score are then used to assign the significance of proposed or future potential actions/activities that have been labelled as potential threats to local drinking water sources. These 22 potential threats as laid out by the province can be seen in the table below in this section (Halton-Hamilton Source Protection Region, 2010<ref name="example3" />).