Best Practices for the Reduction of Air Emissions From Construction ...

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toxics. In addition, emissions from open burning are
highly concentrated.
Municipalities have preferred management
approaches to vegetative waste depending on local
circumstances. These can include mulching,
firewood, resale for cost recovery, used at waste to
energy facilities, etc. Operators should determine
local preferences for addressing vegetative waste and
ensure that this approach reduces dust generation.
During site clearing, vegetative material may be
chipped and then stored for subsequent use as cover
material for vehicle access lanes or storage piles.
6.2.8 Where Possible, Reduce Certain
Activities During Windy Conditions
During times of windy conditions, where feasible,
construction operations that generate greater levels of
dust may be avoided or reduced. Instead, these
activities can be conducted when more favourable
weather conditions occur. Increased application of
other dust suppressant techniques may also be
considered in times of very windy weather.
6.3 Storage Piles
Several work practices can be employed to mitigate
fugitive dust emissions resulting from storage piles.
These work practices primarily reduce the exposure
of storage piles to wind.
6.3.1 Storage Pile Activities Should be
Conducted Downwind
Storage pile activity (i.e., loading and unloading)
should be confined to the downwind side of the
storage pile. This practice applies to areas around the
storage pile as well as the pile itself. Storage piles
should also be located away from downwind site
boundaries.
6.3.2 Utilize Enclosures/Coverings for
Storage Piles
Enclosures or the covering of inactive piles are
effective in reducing wind erosion and controlling
fugitive dust emissions from storage piles.
Enclosures can either fully or partially enclose the
source. Examples of enclosures used for reducing
fugitive dust emissions from storage piles include:
• three-sided bunkers that are at least as high as
the stockpiled materials. The sides’ length must
be no less than equal to the length of the pile;
the sides distance from the pile must be no more
than twice the height of the pile; the sides height
must be equal to the pile height; and the material
of which the sides are made must be no more
than 50% porous;
• storage silos (in lieu of open piles). Bulk cement,
bentonite and similar fine dry materials (e.g.,
less than 3 millimetres in particle size) should be
stored in silos. Silos should be equipped with
particulate matter emission control technology
(e.g., fabric filters); and
• open-ended buildings or completely enclosing
the pile within a building furnished with
particulate matter emission control technology.
Tarpaulins, plastic, or other material can also be used
as a temporary covering. When these temporary
coverings are used, they should be anchored to
prevent the wind from removing them. Small or
short-term inactive storage piles should be enclosed
or kept under sheeting while larger inactive storage
piles should be shrouded, capped or grassed over. For
example, turf removed early in the construction
project may be re-used to grass over long-term
inactive storage piles. It should be noted that
enclosures/coverings may not be suitable under
certain conditions.
6.3.3 Utilize Wind Fences/Screens for
Storage Piles
Porous wind fences/screens provide an area of
reduced wind velocity that reduces wind erosion
potential and fugitive dust emissions from the
exposed surface on the leeward side of the
fence/screen. Wind fences/screens reduce the
turbulence generated by ambient winds in an area the
length of which is many times the physical height of
the fence. It should be noted that wind fences/screens
may not be suitable under certain conditions.
Wind fences/screens can either be man-made
structures (e.g., wind fences, berms, parking
construction equipment in a position to block the
wind) or vegetative (see below) in nature and are
Best Practices for the Reduction of Air Emissions From Construction and Demolition Activities 18