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Accordingly, for the purposes of source protection planning, the wellhead protection area has been divided into the following parts:
→Wellhead Protection Areas (WHPAs)
A Wellhead Protection Area (WHPA) is an area located on the ground surface that denotes a specific zone within a known aquifer where fresh groundwater flows to a pumping well. Any detrimental activities/actions that take place in this zone may contribute to pollutions that can infiltrate into the underlying soil below and in turn contaminate said groundwater source for private and municipal wells alike - hence undertaken in this area may release pollutants that could seep into the soil and contaminate the groundwater used by both domestic and municipals wells. As a result, these areas require high levels of monitoring, protection and enforcement. Accordingly, this area warrants greater protection.
A Wellhead Protection Area (WHPA) is an area located on the ground surface that denotes a specific zone within a known aquifer where fresh groundwater flows to a pumping well. Any detrimental activities/actions that take place in this zone may contribute to pollutions that can infiltrate into the underlying soil below and in turn contaminate said groundwater source for private and municipal wells alike - hence undertaken in this area may release pollutants that could seep into the soil and contaminate the groundwater used by both domestic and municipals wells. As a result, these areas require high levels of monitoring, protection and enforcement. Accordingly, this area warrants greater protection.
The risk to groundwater quality at the well site is determined by the rate at which a specific pollutant/contaminant can infiltrate and travel to the well and the time it would take to remediate the contaminant from the water supply by trained municipal water operators.
The risk to groundwater quality at the well site is determined by the rate at which a specific pollutant/contaminant can infiltrate and travel to the well and the time it would take to remediate the contaminant from the water supply by trained municipal water operators. If a chemical/contaminant spill were to happen a far distance away from a known well, a follow up assessment will be required, this assessment includes:
* Determining whether the contaminant could reach the well in question and the duration of time it may take to reach it.
* Is the contaminant a human, biological or environmental risk or is it simply an aesthetic nuisance?
* Will the concentration of said contaminant exceed the Canadian Water Quality Guidelines (CWQG) for drinking water standard or the Provincial Water Quality Network's (PWQMN) standard (i.e. [[Salt#Guidelines|chloride levels]])?
* Will the current mitigation/treatment protocols currently used be sufficient enough to mitigate/remove the harmful concentration levels of said contaminant from reaching the well?
** If said mitigation/treatment protocol needs to be amended and time allows a mitigation system can be installed to limit the movement of said chemical to the well or the water treatment process at the receiving Water Treatment Plant (WTP) can be modified to sufficiently decrease the concentrations being received
When it comes to WHPAs once size does not fit all, there are multiple zones that extend in an irregular radius around a well to ensure adequate protection of the source water protection area, which is divided into five (5) zones based upon contaminant travel time within groundwater sources:
''For example, if a chemical spill occurs a considerable distance away from a well, an assessment will be required. The assessment considers whether the spilled chemical will reach the well and how long it will take; whether the chemical is a health risk or an aesthetic parameter; whether the concentrations of the chemical at the well will exceed the provincial standard; and whether the existing treatment process is adequate to remove or reduce the concentrations of that chemical. If sufficient time is available, a mitigation system may be installed to limit the movement of the chemical to the well or the water treatment process may be modified to adequately lower the concentrations. If time is available, the risk to the water supply is lower.
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# '''WHPA-A''' – an area of 100 metre radius around the wellhead
# '''WHPA-B''' – the zone through which it takes groundwater to travel between two years and the 100 metre distance
# '''WHPA-C''' – the zone through which it takes groundwater to travel between five and two years
WHPA-A – an area of 100 metre radius around the wellhead
# '''WHPA-D''' – the zone through which it takes groundwater to travel between 25 and five years
WHPA-B – the zone through which it takes groundwater to travel between two years and the 100 metre distance
# '''WHPA-E''' – the area on ground surface through which surface water flows in two hours to a point close to the well. This wellhead protection area is only delineated when studies have shown that surface water can relatively easily seep through the soil and impact the quality of the water at the well. This situation is known as groundwater under the direct influence of surface water, or a GUDI well}} (Halton-Hamilton Source Protection Region, 2010<ref>Halton-Hamilton Source Protection Region. 2010. Wellhead Protection Areas (WHPAs). Planning Process - Vulnerable Areas. Accessed 02 June 2022. http://protectingwater.ca/planning.cfm?smocid=1440&parentcatid=841#:~:text=A%20wellhead%20protection%20area%20(WHPA,both%20domestic%20and%20municipals%20wells.</ref>;
WHPA-C – the zone through which it takes groundwater to travel between five and two years
WHPA-D – the zone through which it takes groundwater to travel between 25 and five years
WHPA-E – the area on ground surface through which surface water flows in two hours to a point close to the well. This wellhead protection area is only delineated when studies have shown that surface water can relatively easily seep through the soil and impact the quality of the water at the well. This situation is known as groundwater under the direct influence of surface water, or a GUDI well''
====Intake Protection Zones (IPZs)====
====Intake Protection Zones (IPZs)====