Concerns Regarding Upstream…

Concerns Regarding Upstream Monitoring Data and Missing Consideration of Water Withdrawals in the Assimilative Capacity Study (ACS).

I am submitting this comment to express concerns about the adequacy of the upstream monitoring dataset used in the Assimilative Capacity Study (ACS) for the proposed Searchmont Resort Wastewater Treatment Plant (WWTP), and the absence of any consideration of the resort’s permitted water withdrawals from the Goulais River (Permit to Take Water No. 8654-BFBRPR). Both issues together materially affect the validity of the ACS back‑calculations and the feasibility of the proposed effluent limits.

Here are the specifics I am asking the MECP to review and carefully consider:

1. Insufficient Upstream Monitoring Dataset

The ACS relies on 20 samples collected over approximately 16 months at upstream, POD, and downstream locations. This dataset does not meet MECP’s expectations for assimilative capacity assessments, which typically require:

- 2–3 years of seasonal data
- Winter dissolved oxygen and temperature data
- Storm‑event sampling
- Continuous monitoring where possible

The ACS contains limited winter data, no continuous DO or temperature monitoring, and no storm‑event sampling, despite the fact that storm events drive phosphorus, bacteria, sediment, and turbidity pulses in northern rivers.

Most importantly - because the ACS uses the upstream dataset to establish background concentrations, determine PWQO compliance, and calculate allowable increases, the limited dataset undermines the reliability of the back‑calculations.

2. Upstream Water Quality Already Exceeds or Approaches PWQOs

The ACS reports:

-> Upstream Total Phosphorus (TP): 0.030–0.043 mg/L
-- PWQO = 0.030 mg/L
-- This indicates the river is already at or above the guideline, triggering Policy 2 (no further degradation).

-> Upstream E. coli: up to 98 CFU/100 mL
-- PWQO = 100 CFU/100 mL
-- The ACS then sets the POD effluent concentration at 99 CFU/100 mL, effectively using the entire assimilative capacity.

-> Incomplete nitrate and ammonia data
-- Nitrate is not consistently reported.
-- Ammonia speciation is incomplete.
-- No pH/temperature pairing is provided for un‑ionized ammonia toxicity calculations.

Given these exceedances and data gaps, the ACS should not rely on this dataset to justify additional loading.

3. Missing Consideration of the Resort’s Water Withdrawals (PTTW)

-> The proponent holds a Permit to Take Water authorizing:
-- Up to 131,000 L/day from a well for potable supply
-- Up to 11,498,000 L/day from the Goulais River for snowmaking, for 80 days per year

These withdrawals occur during cold, low‑flow periods, when:

- Dilution capacity is lowest
- Ammonia toxicity risk is highest
- Dissolved oxygen is most sensitive
- Ice cover reduces mixing

However, the ACS:

- Assumes fixed flow conditions
- Assumes instantaneous mixing
- Does not incorporate water withdrawals into flow or dilution calculations
- Does not assess how snowmaking alters timing, temperature, or pathways of return flows

Ignoring these withdrawals results in an overestimation of assimilative capacity and an underestimation of downstream concentrations.

4. Effluent Limits in the Design Brief Lack Supporting Evidence

The Design Brief includes a table of monthly average effluent objectives and limits (e.g., TP 0.11–0.15 mg/L, TAN 0.50–2.3 mg/L, E. coli 150–200 CFU/100 mL), but:

- Provides no performance data from similar systems
- Provides no cold‑weather analysis
- Omits nitrate entirely
- Does not explain how these values were derived
- Does not link these values to the ACS modeling assumptions

The ACS back‑calculations rely on these values without demonstrating that they are achievable under real‑world conditions.

5. Request

Given the concerns above, I respectfully request that MECP require:

1) A reassessment of the ACS using a sufficient upstream dataset that meets MECP guidance.

2) Inclusion of the resort’s permitted water withdrawals in all flow, dilution, and assimilative capacity calculations.

3) A clear demonstration of how the proposed effluent limits can be achieved under winter conditions, variable flows, and realistic operational scenarios.

4) Re‑evaluation of the proposed effluent limits in light of Policy 2, existing PWQO exceedances, and the limited assimilative capacity of the Goulais River.

Thank you for considering these comments. Please note the ACS is also the only supporting document that the public was given access to prior to the ECA application.