About Phil Brown

Phil Brown edited the Adirondack Explorer from 1999 until his retirement in 2018. He continues to explore the park and to write for the publication and website.

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Comments

  1. Thomas Hart says

    It is true that self-oxidizing steel guardrails do not have the same lifespan as do galvanized guardrails. Although the aesthetic of the brown guardrails is in keeping with the Adirondacks woods and color themes, they also offer an advantage in not shedding zinc contamination to nearby waters.

    Zinc is often the most prevalent heavy metal contaminant in highway runoff. Being adjacent to relatively pristine waters of Beede and Roaring Brooks flowing to the Ausable and to the North and South Branches of the Boquet flowing in the other direction, I would hope that the decision to use galvanized steel considered the potential impacts on water quality and zinc accumulation in fish in these sensitive waters.

    I’ve used the self-oxidizing guardrails along route 73 as an example of a forward thinking means of limiting introduction of zinc into pristine waters in reviews of stormwater runoff analyses of other highway projects. It would be unfortunate if the DOT has decided to replace the self-oxidizing guardrails with galvanized steel guardrails without due consideration of potential adverse impacts associated with zinc as noted.

  2. Alana Fossa says

    Hello Thomas Hart,

    The amount of zinc used to protect steel structures from corrosion is small compared to the structure itself and the addition of zinc into waterways after storm events or on an average annual basis is even smaller. As the galvanized steel weathers over time, zinc corrosion products (zinc oxide, zinc hydroxide, zinc carbonate) may be added to the existing background level of zinc in the water, but only on a very temporary basis. Even if there are multiple sources of zinc on a river, the dilution factor and suspended solids removal is such the natural background level of zinc is relatively unchanged approximately 2500 feet downstream from each zinc source.

    Many case studies have shown, this addition of zinc to the water environment does not cause the background level of zinc to exceed the criterion level defined
    by the U.S. Federal Clean Water Act as the amount of zinc in water causing toxicity to aquatic organisms.

    The American Galvanizers Association publishes a free white paper containing six case studies and information addressing common misconceptions:
    https://galvanizeit.org/education-and-resources/publications/zinc-in-the-water-environment-white-paper

    • Brent says

      Thank you Alana Fossa for the actual science explaining the real-world impacts of the materials in question as opposed to the previous comment which was simply loaded with potentially fear inducing “sciencey” speak that so many these days fall for.

  3. Tom Hart, Environmental Scientist says

    Relative load levels from metal contaminants in storm water according to the Transportation Research Board’s Bridge Stormwater Runoff and Treatment Report (Taylor et al. 2014) compiled over 11,000 sample results from the Highway Runoff Database and the National Stormwater Quality Database. The data uniformly documents Zinc as the most prevalent contaminant. A value of 0.33 mg/L of Zinc is reported which is much higher than Copper (0.082 mg/L) or Lead (0.062 mg/L). More toxic contaminants like Chromium, Cadmium and Cyanide run at levels at 100th the amount of Zinc.

    Contaminant loads in sediment tend to mirror the relative levels found in highway runoff.

    Using a lethal level dose as the protective measure is the absolutely wrong metric here. A better metric is whether the the existing water and sediment contaminant level is low in these rivers, and if they are relatively pristine, what the impact of introducing new levels of contaminant may mean. It’s like the commercial asking if you’re ok with your drinking water having a safe level of lead contamination. In these Adirondack rivers, the affect of metals, including zinc, have heightened toxicity based on the relatively high levels of acidified snowpack runoff.

    At issue here is whether the effort has been taken by NYS DOT’s environmental section to determine if a linear source of zinc represented by miles of guide rail replacement has an adverse impact on river water quality running adjacent to the highways. I hope that due diligence was done prior to making the decision to move forward.

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