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| purpose | considerations
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PURPOSE
The purpose of Annex B is to provide guidance for organizations to consider
when identifying areas of a receiving environment that may be particularly
sensitive to road salts. Once a vulnerable area has been identified, organizations
may then determine the level of vulnerability and the need to implement
additional salt management measures.
Additional salt management measures in vulnerable areas may include:
- using technologies that further optimize the use of road salts;
- using environmentally, technically and economically feasible alternatives
to road salts;
- increasing monitoring and measuring of chlorides and/or their impacts;
- locating patrol yards and snow disposal sites outside of vulnerable
areas; or
- considering location and protection of vulnerable areas in the design
of new roads and/or upgrading of existing roads.
It is important to note, when identifying vulnerable areas, that an area
may be vulnerable either to infrequent but heavy addition of road salts
or to light but frequent addition of road salts.
Organizations may consider consulting with entities that conduct, under
their programs, work that could be relevant to the identification of areas
vulnerable to road salts. In addition, organizations may wish to exchange
information with other organizations adjacent to or having common authority
over these vulnerable areas, and consult with their
constituents.
Notes:
- Subsection 36(3) of the Fisheries Act prohibits the deposit
of a deleterious substance into water frequented by fish. Nothing in
this Annex should be interpreted as an authorization or recommendation
to ignore this prohibition.
- The recommendations described above are intended to complement road
salt management procedures already established in areas identified,
designated or protected by a local, provincial, territorial, aboriginal,
national or international system or body as ecologically significant
or ecologically important.

CONSIDERATIONS
When identifying vulnerable areas, organizations should consider:
- areas draining into bodies of water, such as:
- lakes and ponds with low-dilution and long residence times;
- watercourses that experience the cumulative effects of a dense
network of highways; and
- provincially significant wetlands adjacent to roadways
where the addition of road salts has the potential to significantly
raise the chloride concentration of the water to the point where it
could present a threat of serious or irreversible environmental damage;
- areas draining into small, moderately deep lakes, where the addition
of road salts has the potential to create layers of water of different
salinity within the lake that prevent normal vertical mixing of the
water (meromictic conditions);
- areas where the addition of road salts has the potential to raise
the chloride concentration, after mixing, to levels that could harm
local fish or fish habitat;
- areas adjacent to salt-sensitive native or agricultural vegetation,
where the addition of road salts has the potential to cause severe reductions
in flowering and fruiting, severe foliar, shoot and root injury, growth
reductions, or reductions in germination and seedling establishment
caused by elevated soil levels of sodium and chloride or aerial spray
of sodium and chloride;
- areas where the addition of road salts has the potential to harm the
integrity of a life cycle (e.g. spawning grounds, nursery, rearing,
food supply and migration areas for birds);
- areas where the addition of road salts has the potential to harm a
habitat necessary for the survival or recovery of a wildlife species
listed on the List of Wildlife Species at Risk (Schedule 1 of the Species
at Risk Act) where the area is identified as the species’
critical habitat in the recovery strategy or in the action plan for
the species established under that Act;
- areas draining into sources of drinking water (surface water or groundwater,
including wells), where the addition of road salts has the potential
to raise the chloride concentration of the water to the point where
it could not be used as a source of drinking water. Due regard should
be given to background concentrations of chloride and other possible
sources of chloride in making such a determination;
- areas draining into groundwater recharge zones or that have an exposed
or shallow water table, with medium to high permeability soils, such
as medium to coarse sand and gravel, where the addition of road salts
has the potential to significantly raise the chloride concentration
of the groundwater to the point where it could present a threat of serious
or irreversible environmental damage.
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