SCIENCE/TECHNOLOGY
The committee's recommendations for evaluating bioremediation techniques are necessarily general, but leave no doubt about the necessity for professional operation of a cleanup project. It is not enough to show that microbes grown in a laboratory have potential for degrading contaminants in situ. It is necessary to demonstrate that microbial action is, in fact, operating at the decontamination site. The general strategy recommended by the committee designates three types of information that must be included: • Documented loss of contaminants from the site. • Laboratory assays showing that microbes from the site have the potential to transform the contaminants. • Data showing that biodégradation is actually realized in the field. Every well-designed bioremediation project should meet these requirements as a minimum, the report says. However, there are usually additional requirements, depending on the nature of the site. In fulfilling the minimum requirements, operators would usually document contaminant loss by continuous monitoring of the site. Laboratory assays, the report says, should be conducted using accepted, standard procedures. The hardest thing to demonstrate is that the microbes are actually working on the site; that would usually be documented by analysis of field samples. The additional technique of modeling experiments is helpful, but all three minimum requirements must be included in the design of a project. The committee recognizes that one of the biggest evaluation problems results from the very slow flow rates in most subsurface fluid flow. This technical limitation can be overcome, it points out, by using a large number of test samples, employing models that give the greatest weight to the most important site variables, and generously overdesigning the project. No remediation procedure is perfect. Too many things are too little understood to permit designing a project for all eventualities. But the committee notes that this is the greatest argument for a consistent, in-depth evaluation for each job. The NRC report, "In Situ Bioremediation: When Does it Work?" is available for $29.95 from the National Academy Press at (800) 624-6242 or (202) 334-3313. Joseph Haggin
Materials chemistry workshop series debuts Imagine being served a sumptuous five-course meal in a fine restaurant— and being given only 15 minutes to enjoy it. That's what the first National Science Foundation (NSF)-sponsored Materials Chemistry Workshop was like. The workshop, held late last month in Albuquerque, N.M., tantalized its select group of 35 participants with a rich smorgasbord of materials topics. But the feast—a rapid-fire succession of 30 halfhour presentations on research results— was so tightly crammed into two days, and much of the material was presented so hurriedly, that some listeners found it difficult to absorb, much less savor. The workshop, as envisioned by its organizers, chemists Mark J. HampdenSmith of the University of New Mexico, Albuquerque, and William E. Buhro of Washington University, St. Louis, was to be a forum for "provocative and stimulating discussion of new directions" in the emerging field of materials chemistry, ac-
cording to their NSF proposal. "Polished" talks of the type typically given at national meetings of the American Chemical Society would not be tolerated, they promised. The talks would be required to focus on "the development of ideas, rather than [be] a straightforward presentation of recent research results." Furthermore, Hampden-Smith and Buhro asked presenters to limit themselves to 10 overhead transparencies and to 20 minutes of lecturing, thus leaving at least 10 minutes of their half-hour slots for open discussion of the topic they presented. But, as Buhro admitted at the conclusion of this first in what is expected to be a continuing series of materials chemistry workshops, "We didn't exactly get what we wanted." During an animated, hour-long discussion that ended the workshop—or "sweatshop," as one speaker jokingly called it—some participants voiced their disappointment. For example, Kim R.
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SCIENCE/TECHNOLOGY speakers "fell short of trying to educate," she says. They simply lapsed into their standard mode of giving jargon-filled talks on their latest results, presented in a way that only other specialists in their subfields could digest. In a similar vein, Seth R. Marder, a specialist in nonlinear optical materials at the Jet Propulsion Laboratory in Pasadena, Calif., remarks to C&EN, "I found out a lot but I didn't learn that much." More than one particiHampden-Smith (left), Buhro: forum for interactions pant remarked that some speakers showed up with Dunbar, an inorganic chemistry professor a hefty stack of "overheads" and tried at Michigan State University, East Lan- to show as many of them as they could sing, had hoped the workshop—the first in 30 minutes, leaving scarcely any materials meeting she had ever attend- time for questions or discussion. No ed—would be an educational experience, less than five of the 30 talks focused on an aid to chemists like her who are just various aspects of chemical vapor degetting into the materials field. Many position. Yet, as David C. Johnson of
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the University of Oregon's chemistry department observes, there was no discussion of where this important thinfilm deposition technique is going. Several other participants criticized the lack of discussion time, and offered remedies for future workshops. One suggestion was to schedule distinct discussion periods apart from the presentations, making it harder for long-winded speakers to eat into discussion time. Other ideas to correct the workshop's deficiencies include shorter talks, fewer talks, a smaller number of participants along with longer talks, enforced limits on the number of overheads, a lengthier workshop, and more time to socialize. Buhro and Hampden-Smith say they will carefully consider these suggestions as they begin to plan the second Materials Chemistry Workshop, to be held next year in St. Louis. Despite the criticisms (some of which are labeled "unfair" by other participants), the workshop pleased many. Several attendees, responding in a questionnaire, said they enjoyed the tightly packed program, one even giving it an "A+ for intensity." Others praised the high scientific caliber of the talks. Chemistry professor Walter G. Klemperer of the University of Illinois, Urbana-Champaign, is impressed with the "incredible diversity" of topics covered. That diversity included zeolite inclusion chemistry, fullerenes, interfacial force microscopy, ceramic-polymer composites and other hybrid materials, sol-gel films, cement-based materials, spider silk, selfassembled monolayers, sonochemistry, liquid crystals, supramolecular systems, electrospray mass spectrometry, and novel intermetallic compounds. And some of the talks were exemplary. For instance, Randolph V. Lewis of the University of Wyoming, Laramie, perhaps came closest to mesmerizing his listeners by describing how he and his coworkers harvest silk from laboratory-housed spiders and then proceed to unravel its molecular mysteries. Lewis, who works in Wyoming's molecular biology department and is not an "insider" in the materials field, says, "I learned a tremendous amount." And Seymour J. Lapporte, the program director in NSF's Chemistry Division who gave the green light for the workshop, thinks that for a first-time effort, the workshop was "terrific—and it should improve with time." Ron Dagani
