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#190 - Incinerator Ash--Part 2: All Wastes Must Go Somewhere Forever, 17-Jul-1990

The garbage incineration industry is in serious trouble. For
nearly a decade they have been promoting incinerators all across
the United States without asking themselves one crucial question:
where will we put the toxic ash produced by these machines?

This particular mistake was first made by builders of nuclear
weapons and nuclear power plants, who built nuclear facilities
all across the country without ever asking themselves, "Where
will we put all the radioactive waste?" Today, fifty years into
the nuclear enterprise, no one has yet found a satisfactory
answer to the question, "Where can we safely store these wastes
for the duration of the hazard, which is thousands of years?" Now
the garbage incinerator people are being forced to ask the same
difficult question.

(Perhaps it is significant that a majority of the companies now
making municipal incinerators used to make nuclear power plants,
before American power companies stopped buying nuclear plants.)

In any case, the crucial unresolved question of waste disposal is
now threatening to wreck the economics of the municipal solid
waste incineration industry. If incineration ash must be handled
as a legally-designated "hazardous waste" and hauled to a
legally-licensed hazardous waste landfill, the increased costs of
shipping and burial will make garbage incineration intolerably
expensive and the whole industry will collapse. Clearly, ash is
an achilles heel.

The problem of waste disposal for the garbage industry is as
difficult as it was for the nuclear industry. The nub of the
problem is that the wastes from both industries contain
substantial quantities of very toxic material. In the case of
nuclear power, it's the radioactive metals (cesium, strontium,
plutonium and so forth). In the case of garbage incinerators,
it's the toxic metals lead and cadmium, but the problem is
essentially the same. The offending substances are metals and
they do not degrade. (In the case of nuclear power, if you wait
long enough [250,000 years, in the case of plutonium], the
radioactivity will cease. In the case of garbage incinerator
wastes, the lead and cadmium will retain their toxicity forever.
In this sense, garbage incinerator wastes are even less
manageable than nuclear wastes.)

The main proposed solutions for nuclear waste all involve very
deep burial in the ground. Some people want to bury them half a
mile below ground in a salt mine in southern New Mexico; other
people want to bury them half a mile below ground in Nevada. The
long-term safety of both these proposals has been challenged on
technical grounds, and the debate continues while the nuclear
wastes pile up all across the nation (and, for that matter, all
across the industrialized world).

These deep-burial solutions are not even being considered for the
toxic ash from garbage incinerators simply because the garbage
industry simply can't afford such an expensive solution.

Instead, we have a coalition of EPA (U.S. Environmental
Protection Agency) officials, incineration company "experts," and
"independent" consultants (who derive their income from the EPA
and from the incineration industry) conspiring to fool the public
into thinking that incineration ash is not dangerous. It's a
classic attempt at "linguistic detoxification."

Back in 1980, the EPA established a test for determining whether
a particular waste is a "hazardous waste" or not. This is the "EP
Toxicity" test. The EPA recently reported that "[Incinerator] ash
frequently fails EPA-approved [EP toxicity] tests for determining
whether wastes are regulated as hazardous, because it leaches
lead and cadmium at levels of concern." [1] You might think this
simple statement would close the book on this matter, that ash
would hereafter be treated as a hazardous waste. However, for
reasons that are not entirely clear, William Reilly's EPA wants
to do special favors for the incinerator industry and so EPA has
declared that the EP toxicity test is unrealistic, that ash "in
the field" may not leach as rapidly as it does under laboratory
conditions required for the EP toxicity test.

The EPA has therefore begun a series of tests to see how quickly
ash leaches toxic lead and cadmium under "realistic"

Pure, natural rainwater is slightly acid (pH of 5.6 or 5.7). Acid
rain has an even lower pH (down to 4 or even 3). But even pure
rainwater is sufficiently acidic to leach metals like lead and
cadmium. However, modern incinerator ash contains not only the
ash itself (the burned waste) but also the lime from the air
pollution scrubber system. The lime is basic or alkaline (the
opposite of acid); it has a high pH (10 or 11). The presence of
the lime is sufficient to prevent slightly acidic rain from
immediately leaching the metals out of incinerator ash. So long
as the lime is present, rainwater will not leach the metals out;
instead, the rainwater leaches the lime out. This leaching of
lime reduces the pH of the ash; but eventually the lime will be
completely leached out, the pH of the ash will drop dramatically,
and rainwater will then begin to leach the metals out. U.S. EPA
agrees with this analysis; indeed, the point is hardly arguable.
As if to confirm the obvious, EPA recently experimented with ash
and lime mixed; they poured slightly acidic water over it and
measured the pH and the metals that were leached. Not
surprisingly, few metals were leached because the whole
concoction was so alkaline that it neutralized the acidic water.
EPA concluded, "The results of these limited laboratory studies
suggest that the alkalinity of municipal incinerator fly ash
probably controls and determines the release of elements [metals]
into leachate until this alkalinity is exhausted." Just what a
chemist would predict.

The EPA tests showed that after nine washings with acid rain, the
pH of the ash-plus-lime mixture dropped from 10.9 to 9.4 because
the lime was being removed by each successive washing. This is
also what one would expect, and the EPA said so. "However, due to
time constraints the work was discontinued after nine
extractions," said EPA, thus avoiding the need to state the
inevitable result that the incineration industry doubtless
doesn't want put to paper:

Slightly acid water (like natural rainwater or like acid rain)
leaches out the lime from incinerator ash. Eventually the lime's
alkalinity will be entirely exhausted; then the rain will leach
the toxic metals quickly. It's only a matter of time, and nature
has all the time in the world. The hazard from the metals in ash
will not degrade with time--the hazard is eternal; and the
phenomenon called rain certainly shows no sign of letting up. It
is inevitable, therefore, that sooner or later ash monofills
(which are nothing more than standard double-lined landfills,
which even EPA says will all eventually leak--see RHWN #37) will
spill their toxic contents into the local environment. Water
supplies will become toxic. Living things nearby will be
poisoned, including humans. Short of heroic (and prohibitively
expensive, and unproven) measures like deep burial in the earth,
there seems to be no solution to this problem. Not making
incinerator ash is the only affordable remedy in sight.

--Peter Montague(National Writers Union, UAW Local 1981/AFL-CIO)


[1] We are quoting an EPA "Environmental Fact Sheet"
[EPA/530-SW-90-029c] announcing release of a thick study called
AND LEACHATES completed for the EPA by NUS Corporation of
Gaithersburg, Md; the fact sheet is available from the RCRA
Hotline at 800/424-9346; the thick study is available for $39.00
from National Technical Information Service [NTIS], Springfield,
Va 22161; phone 703/487-4650 and request publication No. PB

[2] Colleen M. Northheim, Alvia Gaskill, and Gail A. Hansen,
"Development of a Laboratory Test Method for Estimating Leachate
Quality From Municipal Incinerator Ash Monofills." In Theodore
G. Brna and Raymond Klicius, eds., Vol. I of PROCEEDINGS
HOLLYWOOD, FL, APRIL 11-14, 1989, pgs. 3b-39 through 3b-52.
Ottawa, Cn: Minister of Supply and Services Canada, 1989.
Catalog No. En 40-11/14-1989e. NTIS is going to publish this
volume but hasn't yet; we received a copy from Theodore Brna at
919/514-2350 ext. 2683."

Descriptor terms: incinerator ash; incineration; radioactive
waste; plutonium; lead; hlw; epa; william reilly; rain; hazardous
waste; waste disposal technologies; deep well injection; studies;
cadmium; scrubbers; pollution control technologies; testing;