TIPS FOR MINIMIZING STORMWATER POLLUTION
Permits
for stormwater discharges associated with industrial facilities, issued by both
the U.S. Environmental Protection Agency (EPA) and states with permitting
authority, pose a variety of requirements on regulated facilities, but smart
facility operators can be proactive to minimize runoff and stay in compliance.
Today and tomorrow,
we will look at recommendations from the EPA to control stormwater impacts and
potentially reduce the regulatory burden.
Simple
Steps for Minimizing Stormwater Pollution
Stormwater
runoff is the major contributor to the ongoing degradation of our nation’s surface
and groundwater. Although we cannot control precipitation, there are plenty of
ways to control its impact through measures that are both common sense and
required by law. Here are some of EPA’s recommended measures for
commercial/industrial facilities to do their part in minimizing stormwater
pollution.
1.
Detect and eliminate illicit connections, which the EPA defines as “illegal
and/or improper connections to storm drainage systems and receiving water …”
The discharge of industrial waste via illicit connections is illegal because
most such discharges would normally require a National Pollutant Elimination
System (NPDES) permit with specific discharge requirements. Unfortunately,
illicit storm system connections can exist without the knowledge of facility
operators, increasing the potential for illegal discharges.
Facility
operators should also note that local ordinances may authorize municipalities
to inspect facilities for illicit connections, especially when they are
suspected of releasing contaminated discharges into storm drain systems. For
example, when pollutants are found in stormwater systems and no source is
readily identified, local and/or state environmental agencies may be prompted
to investigate all possible sources. As with all regulatory requirements,
ignorance is no defense and even facility owners and operators that were
unaware of an illicit connection could be found liable.
2.
Even when not already required by other regulations, training and educating
employees (and customers if applicable) can help to build good pollution
prevention practices and get everyone on board. The EPA recommends a number of
things to consider in such training:
Information
on material handling and spill prevention and response to better prepare
employees in case of an emergency;
Training
on the purpose, operation, and maintenance of pollution prevention management
practices; and
Ongoing
education with periodic training courses and with signs that remind workers of
their responsibility to use good housekeeping practices.
With
regard to customer education, the EPA recommends informing them of the
company’s efforts to reduce waste and pollution and the use of signage or
written materials “so they will be less likely to contribute to pollution
problems that are ultimately the responsibility of the business.”
3.
General good housekeeping practices can also go a long way toward minimizing
polluted stormwater runoff, and they are also among the least expensive and
most effective. While specific practices are often facility and process
specific, there are several common ones that apply to most. These include:
Limit
the exposure of materials that can be eroded or dissolved by rainfall and
runoff by creating an inventory of all materials on-site that are exposed to
rain and runoff and implementing appropriate exposure-reduction activities and
policies.
Keep
dumpsters and other containers securely closed, store containers under cover,
and cover stockpiled materials, such as gravel, wood chips, and building
materials with plastic sheeting.
Maintain
outdoor areas and keep them clean of litter, garbage, and other refuse. The EPA
recommends such cleanup activities be undertaken without using water or other
means that could wash refuse, grit, grime, and sediments into the storm drain
system. Instead, pick up, sweep, and dispose of nonhazardous refuse in the
garbage and use absorbent materials such as manufactured absorbent snakes,
kitty litter, or sawdust to absorb liquid contaminants.
4.
Another good way to focus operations on source reduction is to conduct an
environmental audit.
According
to the EPA, “a reduction assessment can be performed to evaluate the type and
amount of materials currently used, processes conducted, and wastes generated.”
The results of the assessment can reveal “recommendations for modifying the commercial
process to generate less waste, using alternative raw materials to generate
non-hazardous wastes, and identifying recycling options to reduce the amount of
wastes that require disposal.”
Minimizing
the potential for pollution from contaminated stormwater runoff from industrial
facilities is good for the environment and the bottom line. Beginning yesterday
and continuing today we are reviewing some of Environmental Protection Agency’s
(EPA) recommendations that can help control stormwater impacts at industrial
facilities.
5)
Although many facilities are required by different regulations to implement
spill prevention, control, and cleanup plans, even those that are not should
consider the potential benefits. The EPA recommends the following aspects to
incorporate in such plans:
Spill
prevention is the best way to avoid contaminated runoff so plans should cover
the careful storage of materials in sound, clearly labeled containers, and the
regular inspection and maintenance of equipment;
Outdoor
storage of materials should include provisions for keeping containers covered
and kept on a paved area to protect them from being mobilized by wind and
runoff. Storage areas that are not under a roof “should be designed to drain
with a slight slope (approximately 1.5 percent) to an area that will provide
treatment prior to disposal. Runoff from other areas should be excluded to
reduce the volume of runoff requiring treatment by installing berms, curbs, or
diversions on the perimeter of the storage area;”
For
outdoor liquid storage, secondary containment should be implemented and runoff
or spills from the containment area should be directed to the sanitary sewer
(where permissible) or to an appropriate storage or treatment facility for
reuse or disposal;
Spill
handling procedures should be well-defined for any materials that might be
exposed to rainfall or runoff and should cover both small and large spills,
including requirements for contacting emergency personnel;
Spill
procedures should also “emphasize that spills must be cleaned up promptly and
should specify how each type of material should be handled,” and that use of
water for cleanup is strongly discouraged; and
Drains
or inlets to storm sewers should be plugged during spill remediation to prevent
off-site export of pollutants
6) Keeping equipment clean and well
maintained often requires outdoor washing and other operations that can result
in contaminated runoff. To practice safe equipment washing and maintenance, the
EPA recommends adhering to the following pollution prevention measures:
Water
that results from the cleaning of industrial equipment “must be discharged as
process wastewater to the sanitary sewer and is not allowed in storm drains, in
most cases;”
For
cleaning greasy equipment or trucks, the EPA recommends designating a special
cleaning area with “equipment installed to capture, pre-treat, and
discharge the wash water to the sanitary sewer;”
To
help ensure washing and other activities with spill potential are only
conducted in the appropriate areas, the EPA recommends posting instructional
signs that prohibit changing vehicle oil, washing with solvents, and other
activities in nonwash areas;
Systems
such as sumps and drain lines should be installed to collect washwater for
treatment and discharge to the sanitary sewer; and
During
vehicle maintenance activities, the EPA first advises that such operations be
performed indoors and that all waste materials be properly stored and disposed
of or recycled. When performing maintenance work outdoors, “all oil and grease
should be captured unless precautions are taken to prevent them from being
carried in runoff, such as with the use of absorbent pads in inlets or grates.”
7)
When performing construction, repairs, or remodeling activities, the EPA says
there are several precautionary steps that can be taken to minimize the
potential for stormwater contamination, including:
Mixing
paints only in areas where paint spills can be easily recovered or cleaned, and
using impermeable ground cloths;
Proper
management of paint chips and scrapings to prevent contamination of water or
soil (including any additional requirements for lead-based paint);
Storing
paint buckets and barrels of materials where they will not be in contact with
runoff;
Performing
cleanup of water-based paint brushes and equipment in a sink connected to the
sanitary sewer, while oil-based paint brushes and equipment must be stored or
recycled;
Hanging
drop clothes or draperies during spray painting to shield the user from the
wind, collect overspray, and minimize the spreading of windblown materials; and
Placing
a tarp or ground cloth beneath sand blasting activities to capture the blasting
medium, protect the work area from wind, and capture airborne particles.