Porteau Cove Prov Park - Inspection Report

Inspection Information:

This facility was given a moderate hazard rating.
More information on hazard ratings.

Violations:
A summary of the violations found during the inspection are listed below.

Code	Description / Observation / Corrective Action
503	Failure or inadequate treatment for chemical/physical parameters. Observation: Existing treatment works do not adequately control for manganese and possibly lead. Corrective Action: Provide drinking water that meets the Guidelines for Canadian Drinking Water Quality. The hazard rating for this system will remain set to moderate until this requirement is met.

Comments:
This report documents a site visit on June 13th and provides feedback and recommendations based on McElhanney's Technical Memo #3 dated May 19, 2023 and cover letter dated May 23, 2023. There are two wells being considered as long term sources of potable water for the park. Relevant factors include: meeting the Guidelines for Canadian Drinking Water Quality, GARP status of the new well and providing an appropriate level of treatment, well yield and risk of salt water intrusion, wellhead protection, and the location, access and long-term plan for the reservoir. EXISTING WELL The last 10 years of available data for metals indicates manganese consistently measures above the MAC (0.12 mg/L). The 2019 sample also showed presence of lead at 0.00519 mg/L for the first time, which just exceeds the MAC (0.005 mg/L). Iron fluctuates above and below the aesthetic objective (AO = 0.3 mg/L) with 2019 being the highest observed reading at 1.15 mg/L. Note: the MAC for manganese came into effect in 2019 however the dotted green line on this graph is continuous to illustrate how manganese has consistently measured above this level since 2012. 10 years of data on physical characteristics indicates turbidity and colour are generally low although a dramatic spike occurred in 2019. pH fluctuates above and below the minimum aesthetic objective (7.0). Year 2012 2013 2014 2015 2018 2019 Month of Sample October August September September August September Colour (True) <5.0 <5.0 <5.0 <5.0 <5.0 45.1 Turbidity (NTU) 0.87 1.44 0.3 0.28 0.14 24.5 pH 6.65 6.69 7.54 6.41 7.1 7.59 The McElhanney report speculates a possible cause for the sudden decrease in water quality to be disruption of the filter pack due to ground vibrations from nearby industrial activities, and recommends a few courses of action which seem to be prudent given the circumstances: 1.Conduct more testing to determine if the 2019 deterioration in water quality is temporary or permanent. 2.Carry out an assessment of the existing well's casing and screen assess overall condition and determine whether maintenance is required. 3.Redevelopment of the existing well which may help to improve water quality. Considerations: 1. The goal must be to provide water that meets the Guidelines for Canadian Drinking Water Quality. 2. Any new tests results should be considered along with all available past data when determining the most appropriate form of treatment to meet objective #1. 3. Future analysis should include BTEX (analysis for hydrocarbons) due to activities occurring within the immediate vicinity of the well head, and total organic carbon (TOC) to explore whether colour and turbidity are simply the result of in-organics or whether biological materials are present. 4. Manganese above the MAC may not be the result of recent ground disturbances since concentrations have been stable for more than 10 years, and may therefore remain unchanged after redevelopment. Salt Water Intrusion: The following graph depicts 10 years of data for sodium and chloride in the existing well, which tend to fluctuate relative to each other and are consistently well below aesthetic objectives (< 200 mg/L and < 250 mg/L respectively). It is unclear if these background levels indicate a small degree of salt water intrusion and/or represent a correlation to tide water levels. McElhanney's report indicates there is insufficient data to fully understand whether additional pumping of the existing well to meet future demands could pose a greater risk of salt water intrusion. A monitoring well (or wells) could help to study the risk of salt water intrusion for the existing well, however placement may be difficult due to industrial activities in the area. Nevertheless this should be explored. McElhanney's suggestion to gather additional information via the installation of water level and conductivity sensors seems to be a reasonable course of action in the meantime. Any information which can correlate well water salinity with a) draw-down, b) ground water levels, c) seasons and d) tides should help to improve our understanding of whether this well is at risk of salt water intrusion now and in the future. NEW WELL A single water sample was conducted on the new well following the pump test in December 2020. Manganese was below the MAC (0.014 mg/L), iron was below the AO (0.13 mg/L), and there was no lead detected. Turbidity and colour were also low (0.41 NTU and <5 CU respectively). These results should be interpreted with caution, especially when compared to the existing well. This is because a) they represent a single data point b) past testing of the existing well proves ground water in the area can fluctuate from year to year, c) the single new well sample was collected in December, all other existing well tests were conducted in summer and fall, and d) the new well tested significantly higher for sodium and chloride (86 mg/L and 159 mg/L). These concentrations are 3 times higher than 2019 tests from the existing well. Conclusions: 1. Higher sodium & chloride could be naturally occurring, or salt water intrusion from the pump test. 2. More analysis is needed to pinpoint the source of sodium and chloride and to better characterize the risk of salt water intrusion (e.g. sensors, monitoring wells). 3. Some further testing at different times of the year would provide greater confidence as to the stability of various water quality parameters over time, and under varying conditions. 4. Further pump testing of the new well may be warranted. Well Details: The new well is 76 feet deep and was drilled in Dec 2020. The diameter is 8 inches and the screen is positioned between 63 and 76 feet. The surface seal is 12 inches in diameter and 8 feet deep. Considerations for GARP Status (Ground-Water-at-Risk-of-Pathogens) - The number of bacteriological sample results is currently limited to one. A single negative result is not a stand-alone assessment of overall risk and other potential hazards will need to be considered. - A sewage system conveyance pipe is located within 30 meters of the well (possibly within 3 meters), and is well within the capture zone. The condition of the pipe is unknown. - The well log indicates a combination of silty sand & gravel with no confining (impermeable) layer. - There is a possible hydraulic connection to surface water (further assessment is required to determine the risk of salt water intrusion). - A sewage effluent field, tanks, and pit toilets are situated within 300m of the new well. The Mc Elhanney report indicates these may be outside the theoretical capture zone, however the report also acknowledges several limitations with the initial assessment and recommends further refinement of the capture zone to understand the degree of risk for viral contamination. This further analysis would likely require monitoring wells and once again, positioning could be challenging because of nearby industrial activities on the adjacent land, which is owned by a third party. Any additional information that can provided will be considered as part of any future Construction Permit Applications. However based on the available data and uncertainty regarding some key risk factors, this well would be classified as GARP and would require appropriate treatment to be brought on-line. Wellhead Protection and the Reservoir - Using the available data, a wellhead protection area should be clearly defined for each well, and activities which could threaten water quality should be restricted as much as possible within those areas. - Future development for the campground should incorporate appropriate setbacks (e.g. 30m) for both wells from any potential sources of contamination. - A risk mitigation strategy should be developed in consultation with the DWO, and be implemented to address the sewage conveyance pipe next to new well. - Any long term planning must consider the location, access to, and condition of the existing reservoir and whether relocation and/or replacement would be needed if the new well comes on-line.