National Sludge Alliance
NSA Public Fact Sheet 103
Sludge Magic: From New York City to Sierra Blanca, Texas
2/5/1997
In 1989, New York City had a major problem with sewage sludge which was being dumped in the ocean. The sludge was
too contaminated with toxic pollutants to be used beneficially, Congress had banned ocean dumping because it was
destroying the ocean environment, and it couldn't be disposed of in any other state because of the EPA's proposed
"science-based" sludge regulation. (Public facts # 102 )
While New York State did not change its Criteria for land application of sludge, the EPA's "science-based" sludge use
rules were changed after, "Commissioner Harvey Schultz of New York City's Department of Environmental Protection,
explained in a letter to EPA Administrator Reilly, dated June 5, 1989, that "compliance with the pollutant standards would
be difficult, if not impossible, to achieve." According to the letter, "no disposal option covered by the proposal would be
allowed or feasible for eighty percent of the City's sludge." In closing, Mr. Schultz urged Mr. Reilly; "Considering the
economic and environmental importance of these regulations, the large volume of potentially beneficial sludge affected,
and the cost and paucity of landfill space, I urge you to devote the necessary resources to revise 503 in accordance
with the best available technical information."" (Bynum, James W., 1996. Report to National Sludge Roundtable, Toxic
Sludge is Safe for Your Food says National Academy of Science (NSA). p. 144. Laredo Safety Institute. Laredo, TX.)
Did EPA change the concentration levels for the 10 toxic pollutants addressed in the final 40 CFR 503 regulation to
reflect the needs of Commissioner Schultz and New York City?
In 1996, according to the NAS report, "it costs New York City $800.00 a ton to ship the sludge out of state. (p. 152) Yet,
according to an article in the Waukesha Freeman dated 5/18/1996 it would only cost the City of Waukesha, Wisconsin
$25.00 a ton to have the sludge hauled off as a fertilizer. Furthermore, the city is only paying $26.89 to dispose of
sludge in a landfill. That is only $1.89 a ton difference between the two options which is a very small price for the added
safety of disposal in a legal landfill." (Bynum. 1996)
"Yet, the Wisconsin costs for sludge dumping is even high by California standards. According to a Pima Gro Systems
letter to Imperial County, dated May 17, 1996, "Throughout California, municipalities are paying from the high teens and
low twenty dollar per ton range for biosolids reuse; disposal into landfills are often twice these cost." (Bynum. 1996)
"The question is, why would New York City pay $800.00 per ton to ship sludge to the western states when other
municipalities are paying less than $30.00 a ton for disposal?" (Bynum. 1996)
According to the Water Environment Federation / EPA Biosolids Fact Sheet 1 (1995), New York City sludge pollutant
contaminate concentrations are down dramatically when compared to the Federal and State allowable concentrations
and there should be no reason for New York City to ship sludge out of state.
Figure 3 (mg/kg concentrations (ppm))
Federal EQ Sludge MERCO April 1993 NY Limit NYC Average
Arsenic 41 4 75 n/a
Cadmium 39 4 25 120**
Chromium n/a 93* 1000 4230**
Lead 300 193 840 6400**
Molybdenum n/a 7 n/a n/a
Mercury 17 3 10 n/a
Nickel 420 28 200 510**
Selenium 36 5 100 n/a
Zinc 2800 935 2500 3720**
** "July 1979 to June 1981 averages" 5 priority pollutants. Wat. Sci. Tech. (1987) v. 19, n. 9 p.143
According to the WEF/EPA Fact Sheet, the "Federal Table 3 (above Fig. 3) provides pollutant concentration limits for
what EPA defines as 'Exceptional Quality' biosolids-- biosolids exempt from general tracking requirements that can be
used commercially as fertilizer, for example." (p. 4)
As Commissioner Schultz noted, under the proposed science-based sludge rule, 80% of New York City sludge was too
contaminated to be used as a fertilizer in New York State or anywhere else. Yet, the Biosolids Fact Sheet 1 notes,
"Merco handles 27% of New York City biosolids. About 67% goes to the New York Organic Fertilizer Company, where
they are pelletized. Pelletized biosolids have been used on dry wheat farms in Colorado, irrigated cotton and grain farms
in Arizona, and Citrus orchards in Florida. The remaining six percent is landfilled." (p.5)
The question is, what new procedures or methods has New York City found to reduce the pollutant concentrations in its
sewage sludge? Was it pretreatment by industry or different test methods.
According to a New York City study, pretreatment by industry would not help New York City control the toxic metals. "The
1970 to 1972 study of the sources of these heavy metals in New York City waste-water concluded that even with zero
discharge by industry, 94 percent of the zinc, 91 percent of the copper, 84 percent of the cadmium and 80 percent of
the chromium being discharged would continue to be discharged by sources virtually immune to treatment (Ref. 1)."
(Wat. Sci. Tech. (1987) Vol. 19, No. 9. p. 133)
Furthermore, the study found, "For land application, the Task 4 Report used NYDEC criteria (Table 5). It concluded that
because of metals concentration, 94% of New York City Sludge is presently unacceptable for land application. After
pretreatment, either through local limits or categorical standards, 83% to 84% of New York City Sludges would still be
unacceptable for land application. The reason for this is that non-domestic sources of pollutant loading, not industrial
sources, are primarily responsible for interfering with this sludge use." (Wat. Sci. Tech. (1987) Vol. 19, No. 9. p. 142)
Since the improvement was not expected as the result of Federal pretreatment standards, could it be the result of new
test methods and procedures?
According to the WEF/EPA Biosolids Fact Sheet, the test methods and procedures were changed to reflect much lower
pollutant levels in the sludge when compared to the part 503 Tables. "According to EPA, NYCDEP, and TNRCC (Texas),
the biosolids are analyzed and tested routinely for pollutants and disease causing organisms using Toxicity
Characteristic Leachate Procedure (TCLP) test." (p. 5)
The TCLP test measures the amount of a pollutant that can be leached out of a given sample under laboratory
conditions. There is no direct relationship for comparison between the TCLP test result numbers and the Total metals
test result numbers used in part 503. (According to some chemists, the total pollutant to TCLP pollutant leach rate is
about 20 to 1 and the TCLP test does not indicate pathogens)
However, according to the WEF/EPA Fact Sheet, EPA, NYCDEP, and TNRCC, are allowing the sludge disposers to use
the TCLP tests results to indicate compliance with part 503 requirements. The TCLP test results, when compared to the
EPA's part 503 concentration limits, indicate the New York City sludge could be safely used as an uncontrolled
inexpensive fertilizer in New York State, rather than have to pay $800 a ton to ship it to Texas and other states.
The quality of New York City sludge disposed of at Sierra Blanca Texas is even more impressive when compared to the
Federal, New York State and Texas ceiling concentration of pollutants in Figure 2 of the Biosolids Fact Sheet.
Figure 2. Applicable Biosolids Rules for Land Application ( mg/kg(ppm))***
Federal Table NY State TX State NYC Sludge (4/95 TCLP average) 503 landfill limit (75')** NYC sludge (1981)
Arsenic 75 -- 75 4 30 --
Cadmium 85 25 85 4 -- 120
Chromium 0 1000 3000 93 200 4230
Copper 4300 1000 840 193 -- 6400
Lead 840 1000 840 193 -- 6400
Molybdenum 75 -- 75 7 -- --
Mercury 57 10 57 3 -- --
Nickel 420 200 420 28 210 510
Selenium 100 -- 100 5 -- --
Zinc 7500 2500 7500 935 -- 3720
* Chromium concentrations (3000 ppm) was deleted from the 1996 CFR Part 503.
** Please note that Federal Ceiling Limits for Chromium were 2800 ppm above 75' (25 meter) landfill boundary limits.
*** mg/kg is a dry weight calculation. While the dry weight should reflect an apples to apples comparison, this table
reflects an apples to oranges comparison - since the TCLP mg/kg of the April average is not comparable to the Total
Metals Test used in the 503 regulation.
Is it safe and are the test results accurate? According to the Biosolids Fact Sheet, "After treatment in New York City,
Merco voluntarily tests the biosolds to further ensure compliance with metal and pathogen requirements before they are
loaded into sealed containers for shipment to Texas. The city of New York also conducts its own tests."
Yet, according to the Fact Sheet, "In September 1993, a series of human errors in New York City and in Texas led to the
application of nine rail containers of biosolids that had failed to meet the detention requirement for PSRP." (p. 3)
Not only that, but, "In Texas, the regular testing for the presence of pathogen indicators has occasionally revealed
varying levels above the federal and state regulatory limits, causing concern about pathogen regrowth during transport.
However, an independent analysis by Alternative Resources, Inc., of Stroudsberg, Pa. determined that the variations
were most likely caused by inconsistencies in the sampling and analytical methods at the five separate labs conducting
the analysis." (p. 3) -LSI-