Post by Azurerana on Nov 4, 2006 16:56:34 GMT -5
Arsenic found in wells
By EVE BYRON - IR Staff Writer - 11/03/06
Arsenic has been detected in two residential wells below East Helena.
The level of arsenic is below federal drinking water standards, but the fact that measurable amounts are in the wells is prompting Asarco to step up monitoring efforts.
“We need to accelerate our monitoring program … from a bi-monthly to a monthly program,” Asarco’s Environmental Manager, Jon Nickel, told a crowd of about 30 people at Asarco’s annual meeting Wednesday night.
Arsenic was found at a concentration of 3 parts per billion (ppb) in one of the residential drinking wells along Gail Street, and at 6 ppb in a residential well used for irrigation purposes. The federal drinking water standard is 10 ppb.
Arsenic, a known carcinogen, occurs naturally in some soil and rock. It’s also a byproduct of lead smelting, and a century of operations at Asarco’s East Helena plant has led to arsenic concentrations of up to 100,000 ppb on portions of the plant site.
That arsenic has leached into the water underneath the plant and has moved off-site in a narrow plume — something Scott Brown of the Environmental Protection Agency calls “the sleeping giant.”
*
The 600-foot-wide plume is anywhere from 30 to 80 feet below the surface, and stretches north from the plant site under Highway 12, cutting through the northwest side of town toward Wylie Drive. Asarco samples around 100 monitoring wells on a semi-annual basis to keep track of the plume, which is estimated to be moving anywhere from as fast as 300 feet per year to as slow as 265 feet in 50 years.
Article
By EVE BYRON - IR Staff Writer - 11/03/06
Arsenic has been detected in two residential wells below East Helena.
The level of arsenic is below federal drinking water standards, but the fact that measurable amounts are in the wells is prompting Asarco to step up monitoring efforts.
“We need to accelerate our monitoring program … from a bi-monthly to a monthly program,” Asarco’s Environmental Manager, Jon Nickel, told a crowd of about 30 people at Asarco’s annual meeting Wednesday night.
Arsenic was found at a concentration of 3 parts per billion (ppb) in one of the residential drinking wells along Gail Street, and at 6 ppb in a residential well used for irrigation purposes. The federal drinking water standard is 10 ppb.
Arsenic, a known carcinogen, occurs naturally in some soil and rock. It’s also a byproduct of lead smelting, and a century of operations at Asarco’s East Helena plant has led to arsenic concentrations of up to 100,000 ppb on portions of the plant site.
That arsenic has leached into the water underneath the plant and has moved off-site in a narrow plume — something Scott Brown of the Environmental Protection Agency calls “the sleeping giant.”
*
The 600-foot-wide plume is anywhere from 30 to 80 feet below the surface, and stretches north from the plant site under Highway 12, cutting through the northwest side of town toward Wylie Drive. Asarco samples around 100 monitoring wells on a semi-annual basis to keep track of the plume, which is estimated to be moving anywhere from as fast as 300 feet per year to as slow as 265 feet in 50 years.
Article