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<br /> What constitutes failure of a hazardous-wastelandfill?
<br /> From New Jersey's experience I non-radioactive contamination. bottom and sides of a landfill had•to
<br /> can see other potential problems in Lastly, many states (including have a synthetic membrane liner `
<br /> the federal program. First, EPA'•s New Jersey) require construction of overlain by 6" (30 cm) of sand or'.ti,,
<br /> interim regulations (20, p. 33194) landfills out of "im r cable" ma- soil, overlain by 3 feet (1 m
<br /> call for groundwater monitoring for terials with imp cab] efined as soil with a permeability 0-1 c !'l
<br /> four parameters to signal landfill a leak rate f 10–T m/sec. It sec,overlain by a leacha ton k;
<br /> leakage (similar to my study of New became clear i ersey, when system, and so on.Subsequently the F4'
<br /> Jersey's four landfills). However, the state tried to enforce this stan- Agency decided this approach was
<br /> EPA's regulations omit a key etc- dard at the Toms River Chemical `°not completely adequate to assure
<br /> ment: they do not say what will con- site, that there is no way to reach ground-water protection"(19, p. ,4
<br /> stitute the baseline period, to which agreement on the permeabi ity of a 66817) and a new approach was.:;,t
<br /> "new" observations will be com- leaking membrane lin . Th EPA announced.
<br /> pared.This is an important omission acknowledges that l0–' cm/sed.
<br /> c I The new approach(19,24)calls for,:`
<br /> that will cause uncertainty and dis- permeability sianda of appro- risk assessment of any facility. The-,'.,
<br /> pute. As I demonstrated in my priate for membrane liners (21, pp. Agency now acknowledges that all
<br /> ,,Q
<br /> study,selection of different baseline 2837' and 2838). Yet many, states landfills will eventually leak. The
<br /> periods can change the results of the have not recognizedthe problem. question becomes: how much risk is.-`4
<br /> analysis (11). Leakage through a membrane liner thereby created? The Agency says,
<br /> Second, it is not clear from the will occur through a pinhole or " . . .many organic constituents are •..
<br /> regulationsow many monitored aa- through a tear—a concentrated stable (degrade very slowly); other .:
<br /> rameters must incr stream of contamination, which is hazardous constituents (e.g., toxic
<br /> landfill its declared leakirie. If one quite different in effect from a slow metals) never degrade. Yet the ex-,':, I
<br /> out of four increases, is leakage permeation through the entire bot- fisting technology for disposing of kt
<br /> occurring?Two out of four? in New tom and sides of a clay-lined landfill. hazardous wastes on or in the land
<br /> Jersey, even with many parameters Permissible leaka a throu h mem- cannot confidently ? isolate these
<br /> increasing, owners and operators of 6 e in ._be._spccifie in wastes from the environment forev-
<br /> landfills cannot believe that theirons or liter
<br /> ( s1._per_. iiaime. er."Such wastes"will remain poten-
<br /> landfill liners have failed. ---T s matter of defining failure tially dangerous for many thousands
<br /> A related problem is construction goes to the heart of a regulatory phi- of years". And "[s]ince disposing of ,
<br /> of landfills on contaminated sites.At losophy. Although Congress passed hazardous wastes in or on the land
<br /> two of the four, New Jersey sites I the Resource Conservation and Re- inevitable [sic] results in the release
<br /> studied, contaminated soil was used covert' Act (RCRA) six years ago of hazardous constituents to the en- .¢
<br /> in construction of the landfill. This and although roughly 80% of the vironment at some time, any land
<br /> makes it very difficult to discern nation's hazardous wastes go into disposal facility . creates some
<br /> residual contamination from new landfills(8), the EPA has not yet risk."(24, p. 28315)
<br /> landfill leakage. There are many promulgated final criteria for land- Using the new approach, the per-
<br /> reasons to want to build on contami- fills. milting authority (whether the fed
<br /> hated sites but this can only increase On two occasions the Agency has eral EPA or a state agency that has
<br /> the difficulty of monitoring new ac- announced elaborate landfill regula- assumed RCRA duties) would
<br /> tivities. tions, only to withdraw them later. somehow decide how much risk is
<br /> A way out of these problems The first set of regulations(23) es- acceptable from what rates of re-
<br /> would be to require that a tracer be tablished fairly rigid facility design lease of what kinds of hazardous
<br /> added to the wastes. Many tracers requirements. The Agency said at wastes. `
<br /> have been proposed; unfortunately, the time they were using this ap- As I see it, the major problem
<br /> all but one have the advantage that proach because "the state-of-the-art with this approach would be our
<br /> they may be degraded or chemically for predicting discharges or releases inability to define failure. We do not
<br /> bound up by wastes, particularly as from landfills is poor and [the Agen- have quantitative measures of ad-
<br /> the waste stream changes unpredict- cy] thus believes that the only op- verse health or environment effects
<br /> ably. tion available to ensure protection or for the vast majority of hazardous
<br /> Tritium (radioactive hydrogen), human health and the environment wastes. Under this regulatory ap-
<br /> however, does not suffer from these is to prescribe design and operating proach, we would not know when a
<br /> disadvantages. If thoroughly mixed standards which will provide maxi- facility had "failed" until measur-
<br /> with the wastes, it will travel with mum containment in land- able health or environmental dam-
<br /> the leachate. It is easily detected. It fills. . . .[T]he Agency is not aware age had occurred and by then it
<br /> has a half-life of 12.3 years so it will of any method for designing landfills would probably be too late to do
<br /> i disappear in roughly 120 years. For to allow specific constituent release anything about it. In any case, the '1
<br /> any landfill that doesn't accept tri- rates, nor is the Agency aware of EPA has withdrawn the proposal
<br /> f. tium-contaminated wastes, and any method to determine what re- The EPA is under court order to
<br /> p, which is built over an aquifer free of lease rates would be ' accept- promulgate yet another plan for reg-
<br /> tritium contamination, tritium able."(23, p. 58989) ulating landfills. It will be among '
<br /> would seem to be a perfect tracer, The Agency prescribed facility the most difficult regulatory tasks
<br /> easy to distinguish from residual design requirements such as, the ever undertaken.
<br /> September 1982 .,ivil Engineering-ASCE 55
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