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Universal Wastes 553
The amount of mercury in fluorescent lamps is highly variable depending on the type of lamp and
year of manufacture. T-12 lamps (measuring 38 mm or 12/8 in. in diameter) contain significantly more
mercury than T-8 lamps (25 mm or 1 in. in diameter). Additionally, the mercury content per lamp has
declined substantially over the past 15 years. Most 1.2 m (48in.) T-12 fluorescent lamps in use today
contain 20 to 60 mg of mercury, although some have as much as 80 mg and new ones average
22.8 mg. Compact fluorescent lamps are highly variable in their mercury content, with an average of 4
mg (EBN, 1997).
For years, the U.S. EPA considered mercury-containing lamps to be ordinary MSW that
generators could dispose of along with everyday MSW. Landfilling had been the traditional means of
disposing spent lamps (NEMA, 2001). Due to their relatively low mercury content, lamps
have historically accounted for only 3.8% of all the mercury deposited in municipal landfills
(Truesdale et al., 1993). Debate has ensued over the years as to the extent of hazard such disposal may
create. While some studies claim that there is little to no mercury in landfill leachate, others claim that
there are substantial mercury releases in leachate (Massachusetts DEP, 1996; U.S. EPA, 1988).
Until recently most municipal waste incinerators were not equipped with the necessary controls
to reduce mercury emissions. The incineration of mercury-containing lamps released up to 90% of
mercury into the air. By the end of 2000 most incinerators added stringent new EPA-mandated mer-
cury controls, significantly reducing the amount of mercury that incinerators released from any
mercury-containing product (Truesdale et al., 1993).
In 1990 the U.S. EPA revised the test required to identify a hazardous waste, i.e., the “EP-Tox”
test was replaced by the Toxicity Characteristic Leaching Procedure (TCLP) (see Chapter 11).
Under the new test many spent mercury-containing lamps failed and were classified as hazardous
waste. In response, the industry developed numerous types of lamps reduced in mercury content
that could pass the TCLP and which were, therefore, no longer classified as hazardous waste.
Federal law exempts households and CESQGs from handling spent lamps that fail the TCLP. A few
states ban the disposal of all lamps in solid waste, however.
Both large- and small-quantity handlers of universal waste must contain any lamp in containers
that are structurally sound, adequate to prevent breakage, and compatible with the contents of the
lamps. Such containers and packages must remain closed and must show no evidence of leakage. A
handler of universal waste must immediately clean up any broken lamp and place the pieces into a
suitable container.
Safe recycling of fluorescent lamps involves the separation of the three primary components of
the lamp: glass, aluminum end-caps, and phosphor powder (which is where most of the mercury
resides in a used lamp). These components are crushed and separated, thus reclaiming nearly all of
the mercury. The recovered mercury is triple-distilled and sold on the commodity market. Other
recovered materials can also be marketed. The Philips Company, for example, uses substantial
amounts of recycled phosphor in its new lamps (Wilson, 1997).
Recycling has the advantage of reusing potentially hazardous materials from fluorescent lamps,
including mercury. Studies indicate that mercury releases into the air from well-managed lamp
recycling facilities are relatively low. However, the reclaimed glass often contains some residual
mercury that can be released as the glass is distributed through commerce and processed at high
temperatures to make new products. In some areas of the United States the number of lamp recy-
cling operations is still limited. In addition, the market value of the reclaimed materials from lamps
is negligible, such that lamp recycling is not overly profitable and waste generators or government
programs must pay for recycling (NEMA, 2001).

18.5 RESPONSE TO RELEASES
A handler of universal waste must contain releases of universal wastes and its residues. The handler
must determine whether any material resulting from the release is hazardous waste, and if so, must
manage the waste in compliance with 40 CFR Parts 260 through 272.