The 2026 water response

In November 2022 the reviewers told Telkwa Coal its mine plan showed "potential for significant adverse effects to water quality". This is what the company answered, more than three years later.

In brief

Telkwa Mining's answer is that an updated water model no longer predicts the problem. With new inputs, the predicted selenium in Four Creek is about seven times lower than in 2022 and no longer exceeds the provincial guideline. On that basis the company adds one new measure at the mine and builds no water treatment. A treatment plant is designed and permitted in advance, to be built only if monitoring later shows it is needed. The company's conclusion is unchanged: "no significant adverse residual effects".

about 3,300distinct pages of text, filed July 9, 2026 as 13,440 pages in nine files; most pages are repeats

1new measure added to the mine plan (liners in blast holes)

0water treatment plants built under the plan as filed

4rounds of follow-up questions from the two ministries, April to June 2026

Page counts are ours. The nine PDF files total 13,440 pages; comparing the text of every page, 3,303 are distinct and 9,636 repeat a page that appears earlier in the set. Another 384 pages are images with no text and could not be compared. "About seven times" is our division of the two selenium figures in the table below. Quotations: Water Information Request, Nov 23, 2022, p. 4 and Part 1, p. 49.

What was asked

The Environmental Assessment Office's Water Information Request of November 23, 2022 passed on the findings of the environment and mines ministries. They wrote that the model did not show guidelines would be met near the discharge, that exceedances would extend "over many kilometres of multiple watercourses", and that treatment options able to meet the guidelines were "missing from the Application". Telkwa Mining grouped the request into eight themes and answered them in a memo dated January 29, 2026. Source: Part 1, p. 8; Part 1, p. 30; Part 1, p. 32.

The new predictions

These are the company's own figures for the highest monthly average after the mine closes, at the points it models in each creek. Units are milligrams per litre. Figures above the guideline are in red.

Creek	Substance	BC guideline	2022 prediction	2024 prediction
Four Creek	Selenium	0.0020	0.0058	0.00081
Four Creek	Sulphate	309	360	33
Four Creek	Nitrite	0.020	0.038	0.0090
Tenas Creek	Selenium	0.0020	0.0041	0.00079
Tenas Creek	Sulphate	218	260	24
Tenas Creek	Nitrite	0.020	0.045	0.0056

Source: Part 1, p. 7, Table 0-1. The company states that under the 2024 case only two things remain above guideline in the creeks: dissolved copper in Goathorn Creek, which it says is already above guideline today, and cobalt in Four Creek for about four years.

What changed between the two predictions

The memo lists these changes to the model. One of them, blast-hole liners, is a new measure at the mine. The others change the data going into the model or the way it calculates.

New rock chemistry. Leaching rates were re-derived from test barrels of mine rock that have sat outdoors since late 2019. Some rates went up and some went down.
More rain and revised creek flows. Later weather and streamflow measurements showed the 2022 model had under-reported precipitation.
Credit for covering rock as mining proceeds. The model now counts progressive reclamation.
Seasonal background values. Separate winter and summer baseline values are now used.
A different seepage calculation. It now allows for dilution by clean groundwater on the way to the creeks.
Newer climate projections.
Blast-hole liners.

Source: Part 1, p. 4; Part 1, p. 5; Part 1, p. 6.

What was studied and what was adopted

Option	Result	What the memo says
Liners in blast holes	Adopted	Keeps explosive residue out of the rock. Modelled at 75% effectiveness. This is the only new measure added to the mine plan. Source: Part 1, p. 37; Part 1, p. 45.
Thicker pond liners	Not adopted	Modelled seepage from the West pond falls from 836 to 373 cubic metres a day, and from the Tenas Control Pond from 140 to 8. Kept as a contingency for the West pond only. Source: Part 1, p. 35; Part 1, p. 45.
Flocculation to settle fine sediment	Not adopted	Would cut total iron and aluminum in the Tenas Control Pond. Kept as a contingency. Source: Part 1, p. 45.
Wet slurry at the coal plant	Dropped	Judged not effective. Source: Part 1, p. 41.
Storing spring runoff for the water covers	Dropped	Minor benefit, and it brings clean water into contact with the mine. Source: Part 1, p. 41.
Gravel bed reactors (passive treatment)	Not adopted	Kept as a contingency. Telkwa Mining commits to build a pilot during construction, to address the Province's concern about the technology's readiness. Source: Part 1, p. 46.
Water treatment plant (reverse osmosis, bioreactor, lime)	Not adopted	Named as the primary contingency after a December 8, 2025 meeting with the Province. Designed and permitted in advance, built only if monitoring triggers it. Source: Part 1, p. 45; Part 1, p. 46.

Treatment "only if triggered"

The memo says the two treatment systems "were not recommended but should only be incorporated using a Trigger Action Response Plan based on site monitoring". The plan itself is to be written later, during permitting. Source: Part 1, p. 6.

Timing. With designs and permits in hand, a plant could be built "within approximately one year" of a decision. The memo adds that construction "will not necessarily be during the Construction Phase or even during the Operation Phase". Source: Part 1, p. 46; Part 1, p. 47.
A condition on the bond. The commitment is "contingent on the responsible permitting agencies agreeing to not incorporate the permitted water treatment facility" into the mine's financial security until the plant is operating. Source: Part 1, p. 47.
What a plant would not treat. The memo notes that treating surface flows "does not affect groundwater seepage which is the causes of elevated" contaminants in Four and Tenas creeks. Source: Part 1, p. 45.
A ministry's objection. The Ministry of Environment pointed out that pond liners cannot practically be changed once built, and that effects in downstream waters "may not materialize for many years", "potentially decades". Telkwa Mining replied that only the West pond liner remains adjustable, because it is not installed until Year 9. Source: Part 9, p. 5; Part 9, p. 9.

Where the answer shows its limits

The discharge itself still exceeds guidelines. The memo states that "the modelled effluent still does not meet all WQGs at discharge" at the end of the pipe. The company relies on a mixing zone in Goathorn Creek, below the small tributary that carries the discharge. Source: Part 1, p. 47.
The stress test fails for selenium. When the ministry's scenario of tighter liners and higher-than-expected leaching is run, modelled selenium reaches 0.0032 mg/L in Goathorn Creek and 0.0024 in Tenas Creek, against a guideline of 0.0020. Source: Part 1, p. 51, Table 2-15.
One test barrel has turned acidic. After about four years, one barrel of potentially acid generating rock began producing acid. The company says the barrel is a conservative case because the rock was finely crushed. Source: Part 1, p. 5.
The pit walls are predicted to turn acidic. The company's consultant models runoff from the exposed pit walls reaching a pH of about 3 in model year 16. It predicts the water collecting at the pit bottom stays alkaline because other inflows neutralize it. Source: Part 9, p. 117.
The water covers run thin. The mines ministry noted that in the company's own results the water cover is below the level of the acid-generating rock for the first eight years in the West pond, and under half a metre in the East pond early in operations. Source: Part 9, p. 39.
Pond water in the high case. A Ministry of Environment reviewer noted that in the ponds selenium reaches 49 micrograms per litre and sulphate 850 mg/L, with nitrite and nitrate above acute guidelines at peak. Source: Part 9, p. 5.

The dams

The mines ministry had said the three management ponds are tailings storage facilities under the provincial mining code. Telkwa Mining does not accept the label, giving four reasons, among them that acid-generating rock outweighs processed rock by about 11 to 1. It says it will nonetheless apply the tailings-dam standards, citing the ponds' "closeness to population centers such as the Village of Telkwa", and gives a design factor of safety of 1.60. The Dam Breach Assessment Report is re-filed in answer to the ministry's request for a properly sealed copy. Source: Part 1, p. 93; Part 1, p. 94; Part 7, p. 977, Dam Breach Assessment Report.

The drawings of these dams are on the year-by-year page.

What the reviewers said next

Office of the Wet'suwet'en, on the 2025 draft. Water treatment "should be pursued". The plan gives no picture of what happens if a dam, a pump or a water cover fails. With monthly monitoring, exceedances "could persist for a substantial amount of time (months) before any resolution". A breach of the North or Tenas dam should be rated "Very High" for its effect on steelhead spawning habitat. Source: Part 1, p. 101; Part 1, p. 103; Part 1, p. 104.
Ministry of Environment, May 2026. The streamflow model "still underpredicts the median and range of flow conditions by a notable margin in Goathorn Creek and Tenas Creek". The reviewer accepted this as adequate for the assessment stage and said refinement will be required at permitting. Source: Part 9, p. 184.
Ministry of Environment, June 2026. Water volumes leaving one pond did not match volumes arriving at the next, by around ten percent, which was "making it difficult to build confidence in or fully understand the model results". Telkwa Mining reports that a meeting on June 18, 2026 addressed the request. Source: Part 9, p. 198.
The Environmental Assessment Office, August 17, 2026. It accepted the responses as adequate "to enable the effects assessment". That assessment is now under way; see what's happening now.

What is in the nine files

File	Pages	New pages	Contents, by the file's own bookmarks
Part 1	919	737	Cover letter, the 107-page response memo (Attachment A), and Appendices 1 to 5: the updated water model, hydrology, test-barrel results, source terms, and the backfill oxygen study.
Part 2	1,644	663	Appendix 6, first section: SRK's answers to the Ministry of Environment's questions on the water model.
Part 3	1,204	433	Appendix 6, continued.
Part 4	2,259	419	Appendix 6, concluded.
Part 5	1,599	50	Appendices 7 to 11: sewage treatment design, the hydrogeology report, toxicity review, the effect of each mitigation option, and the Best Achievable Technology assessment.
Part 6	2,107	0	Appendix 12: the revised effects assessment for surface water.
Part 7	1,295	657	Appendices 13 to 21: the dilution-zone study, fish advice, rock classification, the acid-drainage management plan, geotechnical answers, the Dam Breach Assessment Report, and the storage alternatives studies.
Part 8	2,185	150	Appendix 22: answers to the Office of the Wet'suwet'en.
Part 9	228	194	Attachments B to E: the four rounds of follow-up questions from the two ministries, April to June 2026, with the answers.

"New pages" counts pages whose text does not appear earlier in the set. Every part opens with the same 107-page cover letter and response memo, and the appendices repeat material at length: Part 6 contains no page of text that is not already in Parts 1 to 5. The files are large (22 to 133 MB) and slow to open.

How far this reading goes

This page is our reading of the submission, and it is partial. It says nothing about how much of the file the government reviewers read.

What we read in full: the opening and Themes 1, 3, 4, 5 and 8 of the response memo, the Office of the Wet'suwet'en comment table, and the cover letters and key answers in the follow-up file (Part 9).
What we have not read: the 22 technical appendices, which make up almost all of the roughly 3,300 distinct pages. Nothing on this page checks the consultants' modelling.
What is not known: whether the ministries now agree with the new predictions. The registry holds their questions as quoted by the company, not their final views. Those should appear in the draft Assessment Report.

Part of the Telkwa Coal public record. See also: the mine, year by year · the review timeline · what's happening now · search the record.