By DAN FOX
A much-anticipated risk assessment report covering Skagway’s Ore Terminal Basin has arrived before the public and Borough Assembly. The assessment was contracted by the White Pass & Yukon Route Railroad, and performed by Golder Associates LTD.
When introducing the risk assessment to the assembly at its Feb. 1 meeting, White Pass President John Finlayson explained that the process for the survey started when the Alaska Department of Environmental Conservation (ADEC) called five potentially responsible parties together over a year ago. At that time, ADEC informed the group that there had never been a proper risk assessment done of the Ore Terminal Basin, leading to White Pass enlisting Golder to do just that.
The assignment, as spelled out in the report, tasked Golder to execute a sampling program in order to help inform risk-based management.
Blair McDonald, senior environmental scientist with Golder, ran through a presentation of the document for the audience and assembly members at that early February meeting.
With all its multiple appendices, the Golder Report comes in well over 1,000 pages, and covers three major issues.
In his presentation to the assembly, McDonald started with the first of these subsections: the Skagway river, and how it deposits sediment directly into the Ore Basin.
By taking five-year slices of bathymetry data – a measurement of depth of water in oceans – and overlaying them, the study revealed a consistent pattern of sediment accumulating in the ore basin.
“Which from a contaminant perspective, that’s not a bad thing,” McDonald said. “The Skagway River is of course carrying a lot of clean sediment, it’s burying the historical ore concentrates – it’s a cap, effectively.”
This being the case, Golder then looked at the level of force that would be needed to stir up the material in question.
The energy from wind and waves is not enough to resuspend the sediment in the Ore Basin, McDonald said, except in the case of a 1-in-50 year extreme storm event.
This is due to the deep drop-off in the harbor, which creates a lot of space for the energy of waves and wind to dissipate in.
The elements aren’t the only things stirring water in the harbor; Golder also looked at the effects cruise ships and ferries may have on the settled sediment.
These man-made disturbances do have the power to upseat the settled materials – this can be seen in the 5-year slices of bathymetry data.
“As time has gone on, the scans have gotten better and better, and we are able to see effectively divots in the bottom of the Ore Basin that coincide to where boats are,” McDonald said.
The divots are not where the main body of ore concentrate lies, according to McDonald, which is right near the ore conveyor facility.
Next, McDonald ran through the effects of sediment samples in terms of toxicology and its effects on three varieties of oceanic critters: Sea urchins, arthropods and polychaetes (marine worms).
Golder tested 11 different sediment samples from various points in the port. The tests measure lethal and sublethal effects of sediment on the organisms, the report states.
When Golder received the results of the toxicity lab, only three samples from the harbor passed the criteria that Golder had adopted for the assessment. Samples gathered farther away from the Ore Basin also failed, McDonald said, despite not containing any elevated concentrations of metals.
Golder was not able to find “any relationship” between effects to the various creatures, and the lead, zinc or any metal concentrations.
This was a surprise, McDonald said, and further experimentation found that amounts of ammonia were building up in the stored samples.
“That’s usually an indication of a wastewater influence,” McDonald said.
The magnitude of the wastewater’s influence is not exactly clear, McDonald said, and he couldn’t give a number on the proportions of what was causing the toxicity in the sediment samples – metals or ammonia.
The final topic McDonald covered in his presentation to the assembly was regarding metals entering the food chain.
Golder collected crabs, prawns and mussels, and sent tissue samples off to be evaluated. With the results in-hand, Golder compared concentration between areas in the harbor, Ore Basin and control areas farther away from the port.
“When we compare between areas, we see that some samples from the Ore Basin, absolutely and unsurprisingly have higher concentrations of metals than the Taiya Inlet, way up, far, far away,” McDonald said.
Samples from the Ore Basin exceed the “conservative” parameters McDonald said Golder used – however so did samples from the reference areas as well, which included samples from where the Taiya River deposits into the inlet, and Nahku Bay.
Exceeding these screening values does not mean there is a risk. The findings do warrant further, in-depth examination, McDonald said – however Golder decided to present its current findings and solicit comments from ADEC.
“Obviously this is a topic that DEC is quite interested in, so we suspect that further evaluation with further input from DEC is certainly warranted,” McDonald said.
Concluding the report, McDonald said that direct effects of metals and ore concentrates appear to be limited, and that there may be other factors that are influencing the quality of the sediment in the Ore Basin.
“But, that continued concentration of metals in shellfish is something that I don’t think should be ignored,” McDonald said. “So Golder’s recommendation to White Pass is, you really should consider a targeted removal of the worst of that material. This is a very common risk-management strategy, you remove the mass.”
McDonald said it isn’t an infinite dredging project, and that there is the ability to focus in on excising a significant percentage of the metals present in the basin.
“Even though that stuff is not massively bioavailable, it’s not leeching a huge amount…it’s enough still that it’s getting into the food chain and it would just be a good practice to eliminate that,” McDonald said.
Following the presentation, Assembly Member Orion Hanson asked McDonald if the risk assessment included guidelines for remediation, such as the volume of soil that needs to be removed and how it would be disposed of. McDonald said that specific information is not in the Golder report, but the future steps would include that information.
Hanson followed up by mentioning the memorandum of understanding between Skagway and White Pass, a document recently approved by the assembly that covers the ground rules of a tidelands lease amendment and new lease agreement for the waterfront.
“Part of that MOU is predicated on cleaning up this Ore Basin, when do you think your report for the remediation process will be due?” Hanson asked. “Because we don’t have a whole lot of time before we have to meet the needs of the cruise ship industry.”
McDonald did not want to speculate on a timeline, saying there is no way to estimate how long it would take regulators to issue permits.
In an interview several days after the meeting, Mayor Monica Carlson said that ADEC and several community stakeholders – including White Pass, the Alaska Industrial Development and Export Authority and the municipality – would be meeting on and reviewing the Golder report at the coming weeks.
Carlson said she’d enjoyed the report, and that she was “happy to hear that he [McDonald] said the lead needs to come out, because we will be dredging, that’s inevitable.”
Tyler Rose, White Pass executive director of human resources and strategic planning, said in a phone interview that ADEC is reviewing the report, and that the state has an additional contractor reviewing it as well.
Rose said that hopefully the report will get adopted in some form, “and what we want to start working on is [a] dredging plan going forward.”
With ADEC approval and after figuring out the “how” and the necessary steps for implementation, Rose said the intent is to move forward with some form of a targeted dredge to take care of a good portion of the mass in the Ore Basin.
“That’s the plan,” Rose said.