Going With the Flow

Eos, Vol. 77, No. 45, November 5, 1996 contributed valuable new observations of ice sheet motion, drainage basin topography, and surface deformations due to volcanic and seismic activity. In Recent Applications of Spaceborne Radar in Geophysics (sessions U41D and U42B), earth and space scientists will discuss how SAR inter­ ferometry has been changed the fields of gla­ ciology, volcanology, seismology, and oceanography. In a four­part program on Sun-Earth Connections: Implementation of the Space Weather Program (SA71A, SA72B, SA1 IB, and SA21A), space physicists will of­ fer insights into the four pillars of current space weather forecast and specification ef­ forts: research, observations, models, and education. In more than 50 abstracts, re­ searchers will discuss everything from the use of artificial intelligence in prediction and modeling to the upcoming launch of the Ad­ vanced Composition Explorer satellite to ways to inform the public about space weather and its hazards. Finally, A Century of Geophysics, ses­ sion U21C, takes AGU members back to their roots. In a session celebrating the 100th anni­ versary of [he Journal of Geophysical Research and its precursors (primarily, Terrestrial Magnetism), historians and scien­ tists will explore the history of the journal and its founding, its role in defining geophys­ ics, and some of the landmark papers that have appeared in its pages.—Michael Carlowicz, with guidance from the Fall Meeting Program Committee In Brief "Scientific analyses indicate that the WIPP repository has the ability to isolate transuranic waste for more than 10,000 years, provided it remains undisturbed by human activity," said Charles Fairhurst, chair of NRC's Committee on WIPP and a professor of mining engineering and rock mechanics at the University of Minnesota. "Also, there are ways to engineer the facility that could be used to reduce the chances of radioactive re­ leases resulting from human intrusion." Going with the flow The Colorado River will never be the same. Declaring success in the controlled flooding experiment con­ ducted on the river in April (Eos, June 11), U.S. Secretary of the Interior Bruce Babbitt has officially changed the operation plan for the Glen Canyon Dam in order to better pro­ tect the natural resources of Grand Canyon National Park and Glen Canyon National Rec­ reational Area. In a ceremony on October 9 in Phoenix, Arizona, Babbitt completed a process that be­ gan during the Bush Administration. In 1989 researchers and land managers began pre­ paring an environmental impact assessment of how the river and dam could be managed to better protect the ecosystem. The new "re­ cord of decision" signed by Babbitt directs the Department of the Interior to operate the dam in "such a manner as to protect, mitigate ad­ verse impacts to, and improve the values" for which the parks were established. The order makes permanent some changes first or­ dered in 1991; those changes allow for (but do not necessarily prescribe) occasional con­ trolled floods and other dam management procedures that minimize erosion down­ stream. "We begin a new chapter in the fabled his­ tory of the Grand Canyon and Glen Canyon Dam," Babbitt said. "This marks a sea change in the way w e view the operation of large dams. W e have shown they can be op­ erated for environmental purposes as well as water capture and power generation." At the press conference, Babbitt also re­ leased a compilation of 34 separate scientific analysis of this spring's controlled flood. Early results indicate that • sand barvolumes along the Colorado River in the Grand Canyon increased by 53%, though the actual lateral area of beaches cre­ ated was 5­7%; • 80% of the sand deposition from the flood occurred in the first 48 hours; • several major rapids on the river were carved and widened; • backwater habitats for fish were in­ creased by about 20%, though the areas were not usable this summer due to high river flows in the wake of high snowpack runoff; • sand deposited by the flood is already eroding, as the natural erosion process oc­ curs at a rate of 7% per year; • the flood appears to have had no nega­ tive impact on bird species or the Native American artifacts and sites along the river. Data and analyses from the controlled flood at Glen Canyon will be presented at the AGU Fall Meeting in San Francisco in a ses­ sion (H32D) entitled Controlled Floods, Natural Floods, and Riverine Processes. —Compiled by Michael Carlowicz PAGE 442 NRC disposed to site A committee of the National Research Council (NRC) has found the risk of human exposure to radiation from nuclear waste to be minimal at a proposed underground disposal site. In a report on the U.S. Department of Energy's (DOE) Waste Iso­ lation Pilot Plant ( W I P P ) in southeastern New Mexico, the NRC committee asserted that the danger of radioactive exposure at the site is unlikely to exceed U.S. and interna­ tional standards for protection from radia­ tion. Unless the site is breached by humans—most likely those drilling for gas or oil—there is no credible or probable chance of the release of the radioactive waste, the committee said. WIPP is a network of chambers and tun­ nels excavated in a layer of geologically sta­ ble salt, 600 m below the surface of the desert. DOE has been investigating the $1.8 billion site since the 1970s; 10 years ago, the agency built the underground facility to hold thousands of tons of plutonium­contami­ nated clothing, laboratory equipment, and machine parts once used to manufacture nuclear weapons. DOE plans to ask EPA this month for certification to open and op­ erate the site—the first permanent disposal site for transuranic waste in the United States—and administrators hope to start de­ positing the radioactive waste by November 1997. This page may be freely copied.