Fall Groundwater Sampling in the Upper Thames River Watershed听
Under the Provincial Groundwater Monitoring Network, the 糖心直播 (UTRCA) manages a total of 28 wells at 22 different sites across the watershed. The program was launched in 2001 as a partnership between the Ministry of Environment, Conservation, and Parks (MECP) in response to the low groundwater levels that were experienced in 1998. The purpose of this monitoring program is to collect long-term groundwater quality and quantity data at the predetermined sites. Ambient water levels and water quality of the major aquifers in the area are the focus for the UTRCA.听
This fall, 22 wells underwent sampling for water quality monitoring. The samples collected were analyzed for general chemistry (phosphorus, nitrogen, chloride), and metals.听听
Additionally, another subset of wells chosen by Health Canada were analyzed for the presence of pesticides.听
Each well and aquifer is unique, including static water level, depth, and volume, requiring water quality monitoring staff to pay careful attention to detail in order to uphold a high quality of both monitoring and sampling protocols. Each well must be purged with a certain amount of water before sampling can be conducted. Deeper wells require longer purge times. This is because we need to ensure that we are sampling the true conditions of the aquifer. Deeper aquifers require more time to access and pump out anything that may skew results, such as anything that may leech in from the surface. The purge time for groundwater wells within the UTRCA watershed ranges from 1 hour to 6.5 hours. During purging, parameters including pH, water temperature, static level, and clarity are taken at pre-determined intervals. 听
In addition, there are multiple types of pumps used to sample the water. Some wells are equipped with dedicated pumps built in, while others require staff to bring power sources and dedicated tubing to prevent contamination from the surrounding environment and separate wells.听 Each sample is sent off to a provincial lab that conducts the analysis, and the data is then made available to the public听