Malaspina researchers study local groundwater

Residents living in rural areas near Nanaimo have a better idea of what is in their drinking water, thanks to the efforts of two faculty researchers at Malaspina University-College.

Geologist Dr. Steven Earle and chemist Dr. Erik Krogh recently completed a three-year study of groundwater in private wells on Gabriola Island and in Yellow Point.

Earle, Krogh and chemistry and geology students obtained permission from homeowners and collected groundwater samples from 72 private wells on Gabriola Island and 102 wells in the Yellow Point area. The samples were analyzed for a wide range of chemical constituents including fluoride, boron, selenium, sodium, arsenic and other potential toxins. They also collected rock samples from the same area.

"Our objective was to study the natural variations of groundwater in the region and to understand how the water is affected by the geological features of the rocks through which it flows," said Earle. "The study did not consider biological contamination, for example, fecal coliforms, although this is a concern of some residents."

Analysis was done in the field, at Malaspina’s state-of-the-art Applied Environmental Research Lab (AERL), and at the School of Earth and Ocean Sciences at the University of Victoria. "All analytical data is maintained in confidence and participating homeowners have been informed of the results," said Earle.

Residents in many rural parts of central Vancouver Island rely on private wells as their main source of drinking water. Much of that water comes from wells drilled into conglomerate, sandstone and mudstone rock of the cretaceous-aged Nanaimo group.

A B.C. Ministry of Environment report published in 1985 showed that a number of wells in Nanaimo area sedimentary rocks on eastern Vancouver Island have fluoride concentrations of about 10 milligrams per litre of water. That's above national and international guidelines of 1.5 miligrams per litre, said Earle.

"That’s why in 2000 we initiated a project to study the distribution of fluoride in the Yellow Point and Gabriola areas, and to understand the geological origins of this phenomenon," explained Earle.

About eight percent of the well waters on Gabriola Island have fluoride levels in excess of the 1.5 milligrams per litre guideline; 13 percent of Yellow Point area well waters have fluoride levels over the guideline.

"As part of our study we wanted to find out why the levels of fluoride are so high, and what proportion of wells have problems," explained Earle. "The answers to these questions can be of great benefit to people living not only here but in other parts of the world."

Excessively high fluoride levels in drinking water can have "serious implications" for dental and skeletal health, said Earle. "Too much fluoride can cause discolouration and deformities in teeth for the young, and brittle bones for the elderly," he said. "If you know your well contains high levels of fluoride, you should avoid giving the well water to young children or the elderly."

Earle said the health issues are greater for people living in third world countries with similar rock formations because "often well water is their only supply of drinking water."

Earle and Krogh’s three-year study received funding support from the Malaspina Research Fund, the Bamfield Scholarship, and the Ministry of Water, Land and Air Protection. They hope to publish a final report about the study in a leading scientific journal. The two researchers are currently studying the geochemistry of rock samples from both the Yellow Point and Gabriola areas, and plan to extend the groundwater sampling project to several other parts of the region.

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