UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF SOLID WASTE MANAGEMENT PROGRAMS
October 17, 1975
SUBJECT: Policy Implications of Sewage Sludge on Hazardous Waste Regulation
FROM: William Sanjour,
Chief Technology Branch (AW-465)
TO: Mr. John P. Lehman,
Director Hazardous Waste Management Division (AW-465)
It is EPA policy to encourage the use of sewage sludge as fertilizer (Tab A). This is done because of the identification of sewage sludge with human excretion. In fact sewage sludge contains a great many things other than excretion. Industrial wastes account for 25% of municipal sewage in fluent nationally and can be almost 100% in some localities. Street run-off accounts for a significant amount. Even domestic wastes contain effluents from laundries, showers, sinks, garbage disposals, etc., so that only a small fraction of the solids which end up in the sludge are from excretion. Sewage sludge is in fact an amalgamation of all the wastes of our society.
When the toxic heavy metal content of municipal sewage sludge (Tab B) is compared with the heavy metal content of industrial sludges, (Tab C) it is seen that they are comparable even for those industries which are reputed to be the worst generators of toxic metals such as electroplating and metal smelting.
Because of the similarity in the origin, the constituents, the environmental impact, the available disposal techniques and disposal costs between municipal sewage sludge and industrial hazardous wastes, it would be impossible to write guidelines or regulations for the latter without taking into account the policy toward the former.
The procedures which OSWMP Hazardous Waste Management Division are developing to define a hazardous waste would certainly classify municipal sewage sludge as a hazardous waste. If municipal sewage sludge comes under the jurisdiction of a hazardous waste regulatory program (which it does not under the proposed S.2150) then it would have to be disposed in a manner where little or no toxic material can escape into the environment.
On the other hand, the policy of EPA toward sewage sludge which encourages (almost demands) its use as fertilizer, is the most efficient means (short of eating the sludge) of injecting toxic substances directly into the human body. It has been conclusively demonstrated that when plants are grown on sewage sludge their cadmium content is increased several hundred percent (Tab D). This is true even when EPA guidelines are followed.
Yet EPA'S Office of Research and Development has published data which says that only a 60% increase in the cadmium levels of the average diet is sufficient to cause chronic kidney damage and a 40% increase will exceed the World Health Organization's recommended levels (Tab E).
What will happen, then, if Congress gives EPA regulatory authority over hazardous wastes? Will we have one policy for hazardous wastes which go through municipal treatment plants and a different policy if it goes through and industrial treatment plant? if so, we will end up in court looking like fools. Will we fail to adequately regulate industrial wastes for fear of compromising EPA's policy on municipal sludge? If so, we will be brought into court for failure to perform our duty.
Clearly there is a confrontation ahead, which can only be avoided by not getting regulatory authority or by changing EPA sewage sludge policy.
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