Posted on: August 8, 2018 | Environment
The following email was sent August 3rd to the Contaminated Sites Program Specialist | Emergency Response Team Member Manitoba Sustainable Development, Environmental Approvals
Thank you for providing the Consulting Engineer’s report and analysis of the soils and leachate from and adjacent to the derailment site. The report is clear and satisfies my concern over the quantity of chemical left behind during the clean-up, and its potential for mobility / transportability in solution as runoff. Given the quantity of both iron and organic matter (peat) in the soil / substrate, together with the information that small quantities of the Nickle and Cobalt can be chemically bound, and / or filtered from the leachate by iron and peat, is very reassuring. Hopefully, the apparent very limited movement of the chemicals prior to the sampling of June 7 th, is indicative of the natural buffering available, and not due to the very limited precipitation and snow melt experienced during the spring period alone.
The railway right-of-way cannot realistically, be considered anything other than “recreational” given that it occupies highly permeable substrate and passes through park land. Further, many of the lakes are populated by the descendants of the railway workers who built the first cottages on these lakes, and many of these cottages were constructed within or very close to the right-of-way. In addition, being a cleared, pathway through the forest, the right-of-way is used as an access route by pedestrians traveling to cottages, by fishermen visiting otherwise inaccessible lakes, by hikers (eg. the Mantario Trail), berry pickers, etc. The swamp adjacent to the North side of the CN line in this derailment site, is supplied by water which drains along the right-of-way for some distance, and thence under the track into Nora Lake. So – to distinguish between acceptable concentrations of contaminants on the right-of way” as anything other than “residential / recreational” areas is not seen as a reasonable thing to do in assessing the level of contamination. In any event, given the information you’ve provided, we are satisfied that the clean-up has been carried out successfully, and that the risk of unforeseen contamination is low. Thank you very much for keeping us informed.
For: Whiteshell Cottagers Association
From: Rospad, Warren (SD) [ mailto:Warren.Rospad@gov.mb.ca ]
The department has received the analytical report (and attached) for the train derailment that occurred back in January. Four sampling events were carried out at the site between May and June of 2018. The report has also been reviewed by the department and has the following comments:
Nickel is naturally present in soils as a result of chemical and mechanical weathering of rock to form soil. Nickel is present in granites, sandstones and limestones but the concentration can occur in high concentrations in ultramafic and mafic bedrock and soils overlying naturally enriched bedrock.
Nickel is naturally released into the Canadian surface waters, sediments and soils by weathering and erosion of geological materials (ie. bedrock and limestone). In the environment, nickel can be found in a variety of inorganic and organic compounds depending on such factors as the medium considered and ambient environmental conditions.
For this purpose a background value of 26.8 mg/kg has been established.
Nickel is generally strongly sorbed and chelated to soil surfaces with iron and magnesium oxides, clays and organic matter where it can substitute for magnesium in the layers of soil which decrease the mobility of nickel. To this end nickel binds to the soil or peat and is not readily mobile or leaches out in these soil conditions.
The natural flow of surface and groundwater in the area is influenced by the marshy area just to the east of the derailment site (not towards Nora Lake). The analytical results following this natural flow of water show no residual nickel or cobalt above referenced guidelines for the site.
CN Right of Way Sampling:
The analytical results show that there is residual nickel and cobalt concentrations located in the spill area on the right of way. However when compared to the appropriate guidelines and pathways for an industrial land use, the values of nickel and cobalt are below standardized and adopted guidelines here in Manitoba. For example, since the appropriate land use for the right of way is industrial, we apply the CCME industrial land use guideline. The appropriate pathway for anyone on-site would be ingestion and dermal contact for which the value set out in the CCME guidelines is 5,100 mg/kg. This pathway is chosen because the only human health concern would be for people working on the site. No person other than a CN employee should be on the right of way. Another factor to consider is particulate inhalation for which a guideline of 10,000 mg/kg has been established. The reported analytical results show that all values for nickel are below those guidelines.
Off Right of Way Sampling:
The analytical results show that for all soil and surface water samples collected (including samples from the lake) are well below referenced guidelines for agricultural/residential guidelines (these are the land use guidelines set out by CCME) and applicable drinking water guidelines for the lake.
In summary, there are residual nickel concentrations within the CN right of way but are below the appropriate human health pathways for the site and the soil and surface water samples collected off of the right of way towards Nora Lake are below the appropriate guidelines and that the risk to human health and the environment on or off-site do not present a risk.
The department does not require any further work to be carried out at the site.
Warren Rospad Contaminated Sites Program Specialist|Emergency Response Team Member Manitoba Sustainable Development, Environmental Approvals