County could
require groundwater studies
By TRAVIS
PURSER
Express Staff Writer
To get a
better picture of how a proposed real estate development might affect
groundwater quality, Blaine County could begin requiring developers to pay
for in-depth groundwater studies before building.
That was
the message two health districts delivered to the Blaine County Commission
Monday during its second meeting in the last two weeks on water-quality
issues.
A current
rule enforced by the South Central District Health Department requires
that no more than one septic system per acre be installed in Blaine
County.
But that
rule was stretched last summer when the county approved an application for
20 systems in a 20-acre neighborhood, even though individual lots were
less than one-acre each.
It is not
known whether that higher density of septic systems, over time, will lead
to contaminants seeping into groundwater. But before approving such
subdivisions in the future, the county might insist on knowing.
Paul
Hunter, a geologist who works for the Idaho Department of Environmental
Quality and the Central District Health Department, told the commission
that requiring nutrient pathogen studies of proposed developments would do
that.
The studies
range in cost from $1,500 to $20,000 and predict whether below-ground
sewage disposal will degrade groundwater.
Some
counties, like Ada, Valley and Elmore, already require the studies for
proposed subdivisions of five or more lots, and from proposed commercial
facilities that would generate 600 gallons or more of wastewater each day.
The studies
can involve collecting soil and water samples, sometimes over a period of
months, and feeding data into a complex computer program that models the
underground flow of contaminants over a period of years.
Information
from the program could help planners cluster development in areas where it
would be the least likely to harm groundwater.
The
information could also identify areas that are especially sensitive to
contamination, where septic systems could be limited or prohibited.
The Blaine
County Drinking Water Protection Committee, which has been meeting
monthly, will consider the information presented Monday as it continues to
draft its Drinking Water Protection Plan.
The plan
would present a framework for revisions to county subdivision laws and
could be completed this summer.
The
committee meets again at 3 p.m. Feb. 20 at the Old County Courthouse.