Work to replace and maintain roadway delineation typically includes refurbishing,
delineation and replacement of missing markers. Environmental stewardship practices
ensure that paints, debris and excess maintenance and repair materials remain controlled
and are not released to the environment.
In September 1999, EPA redefined traffic paint into two categories, traffic marking
coatings and zone marking coatings. Zone marking coatings are defined as those used
on sidewalks, driveways, parking lots, curbs and airport runways and packaged in
containers of five gallons or less, with Volatile Organic Compounds (VOCs) limited
to 450 grams/liter or less; i.e. traditional oil-based traffic paint. Traffic marking
coatings are now defined as those used for streets, highways and traffic areas as
well as the purposes outlined for zone markings, with a VOC limit of 150 grams/liter.
This means that traffic marking contractors must use low-VOC traffic paint when
marking roadways, which in most cases will mean using latex traffic paint. In transitioning
to latex traffic paint, DOTs have had to make sure that equipment is waterbase compatible,
in order to avoid application and maintenance problems. Modifications have included
use of stainless steel on critical wetted parts, with plated components being adequate
in very few areas. New application techniques have also applied, especially for
low-VOC alkyd paints which contain acetone, a product with a low flash point.
for Specific Types of Pavement Marking
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|Paint Striping and Marking
Pavement striping is used for lane stripes and other pavement markings to guide motorists.
Surfaces may be swept prior to painting. Water-based paints are applied using striper
paint systems. Other pavement markings may be applied using striper paint systems
or stencils. Potential pollutant sources such as overspray, dust, spills and leaks
may create pollutants, including paint, sediment, fuel, hydraulic fluid and oil.
Water used during presweeping operations should be controlled to prevent unpermitted
non-stormwater discharges. Other recommended environmental stewardship practices
include illicit connection/illicit discharge reporting and removal, scheduling and
planning, illegal spill discharge control, spill prevention and control, safer alternative
products, vehicle and equipment fueling, vehicle and equipment maintenance, solid
waste management, liquid waste management, material use, sweeping and vacuuming
and water conservation practices. [N]
Raised/Recessed Pavement Marker Application and
Pavement markers supplement traffic signs. Markers may either be surface mounted
(raised) or placed in recessed slots in the pavement. Markers are applied using
bitumen/epoxy adhesives. Damaged markers are removed using hand tools or graders
and loaders. Potential pollutant sources such as excess application, spills and
leaks may result in the release of potential pollutants of epoxy, fuel, hydraulic
fluid and oil. Recommended environmental stewardship practices include illicit connection/illicit
discharge reporting and removal, scheduling and planning, illegal spill discharge
control, spill prevention and control, vehicle and equipment fueling, vehicle and
equipment maintenance, solid waste management, and material use. [N]
Environmental Stewardship Practices for Pavement Marking
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General environmental stewardship practices for pavement marking include the following:
- Schedule pavement marking activities for dry weather. Do not conduct painting
or traffic marking activities during rain events.
- Replace solvent-based alkyd traffic paints with waterborne paints that contain
80 percent less organic solvents and with epoxy paints that release no solvent vapors.
- Develop paint handling procedures for proper use, storage, and disposal of paints.
- Transfer and load paint and hot thermoplastic away from storm drain inlets.
- Provide drop cloths and drip pans in paint mixing areas.
- Properly maintain application equipment.
- Street sweep thermoplastic grindings. Yellow thermoplastic grindings may require
special handling as they may contain lead.
- Properly dispose of paints containing lead or tributyltin, which are considered
a hazardous waste.
- Use water based paints whenever possible. If using water based paints, clean
the application equipment in a sink that is connected to the sanitary sewer.
- Properly store leftover paints, if they are to be kept for the next job, or
dispose of properly.
Traffic Stripe and Pavement Marking
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Waste from removal of yellow thermoplastic and yellow painted traffic stripe and
pavement marking contains lead chromate in average concentrations greater than or
equal to 350 mg/kg and less than 1000 mg/kg Total Lead. Residue produced when yellow
thermoplastic and yellow paint are removed may contain heavy metals in concentrations
that exceed established thresholds and may produce toxic fumes when heated. Waste
from removal of yellow thermoplastic and yellow painted traffic stripe and pavement
marking contains lead chromate in average concentrations greater than or equal to
5 mg/L Soluble Lead or 1000 mg/kg Total Lead. Caltrans has specified the following
environmental stewardship practices for removing traffic stripe and pavement marking:
- Removed yellow thermoplastic and yellow paint should be disposed of at a Class
1 disposal facility or a Class 2 disposal facility. Testing of residue is likely
to require EPA's Total Lead and Chromium Method 7000 series. If the yellow thermoplastic
and yellow painted traffic stripe and pavement marking residue is transported to
a Class 1 disposal facility, a manifest should be used, and the transporter should
be registered with the California Department of Toxic Substance Control. The Engineer
will obtain the United States Environmental Protection Agency Identification Number
and sign all manifests as the generator within 2 working days of receiving sample
test results and approving the test methods.
- The contractor should prepare a project specific Lead Compliance Plan to prevent
or minimize worker exposure to lead while handling removed yellow thermoplastic
and yellow paint residue. Personal protective equipment, training, and washing facilities
required by the Contractor's Lead Compliance Plan should be supplied by the Contractor.
- Prior to removing yellow thermoplastic and yellow painted traffic stripe and
pavement marking, personnel who have no prior training, including State personnel,
should complete a safety training program provided by the Contractor that meets
- Where grinding or other methods approved by the Engineer are used to remove
yellow thermoplastic and yellow painted traffic stripe and pavement marking, the
removed residue, including dust, should be contained and collected immediately.
Sweeping equipment should not be used. Collection should be by a high efficiency
particulate air (HEPA) filter equipped vacuum attachment operated concurrently with
the removal operations or other equally effective methods approved by the Engineer.
- The Contractor should submit a written work plan for the removal, storage, and
disposal of yellow thermoplastic and yellow painted traffic stripe and pavement
marking to the Engineer for approval.
- The removed yellow thermoplastic and yellow painted traffic stripe and pavement
marking residue should be stored and labeled in covered containers, conforming to
state provisions. The containers should be a type approved by the United States
Department of Transportation for the transportation and temporary storage of the
removed residue. The containers should be handled so that no spillage will occur.
The containers should be stored in a secured enclosure at a location within the
project limits until disposal, as approved by the Engineer.
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|Continue to Section 5.6»