News

By: Eleanora I. Robbins, U.S. Geological Survey, 956 National Center, Reston, VA 20192
nrobbins@usgs.gov

By: C. Gordon Winder
University of Western Ontario, London Canada, N6A 5B7

By:Dr. Edward Sudicky,
Chair, Waterloo Earth Sciences Department.

One of the difficulties in evaluating or quantifying groundwater contamination is that it is underground . . . hence, difficult and costly to get at. One way to minimize the cost would be to develop a reliable computer model that would serve as a guide, indicating what is taking place.

Arsenic

Professor Nikolaos Nikolaidis of the department of environmental engineering, University of Connecticut has created an arsenic filter for drinking water supplies. A simple filter using iron filings and sand is being used to treat water contaminated with arsenic. People in countries like Bangladesh and Bengal, where the soil is contaminated with arsenic compounds are suffering from arsenic poisoning. Water from wells contains between 300 and 4000 micrograms of arsenic per litre. Bengalis working in the heat consume up to 20 litres of water a day.

This is the third section of a four-part article dealing with the volcanic eruptions in the Westman Islands, south of Iceland in the decade from 1963 to 1973. Part one covered the eruption of the volcano Surtsey in 1963, and my visit to the island in 1970 (WAT ON EARTH, Spring Issue 1997). Part two covered the early days of the eruption of Eldfell on Heimaey in 1973 (WAT ON EARTH, Fall issue, 1997). In this issue I will describe the continuing eruption until the cessation of activity in 1973.

In a number of communities, water comes from the ground. This unlike many other communities where water comes from lakes or rivers. Groundwater accounts for only about six percent of the total water used in Ontario, over 2.8 million people, 23 percent of Ontario's population rely on it as a source of potable water.

How does the water get into the ground?

Earth sciences students take part in a major field trip at the beginning of their final year. They have a choice of a field trip to Quebec or some more exotic location. Last year, 14 students opted for a two week tour of Nevada, Utah, Colorado and Arizona. Students planned each day's itinerary, contacting local experts to assist with interpretation, they were also responsible for a guidebook and an after trip presentation.

In the last issue of WAT ON EARTH I described ice-wedge polygons, - relict features left over from a short-lived regime of permafrost in southern Ontario in the period immediately after the ice retreat. As I explained, these features are virtually invisible at ground level but they can be clearly seen (under the right circumstances) from the air. The recent widespread media coverage of the floods affecting the southern part of Manitoba brought back some memories of traversing this region in the past, and it reminded me that other strange features can frequently be observed from the air.

Eric Reardon