Grant from Minnesota Department of Health to assist in cost
By Tina Snell, Staff Writer
The city of Little Falls has begun to search for abandoned wells in the vicinity of City Hall and the Water Treatment Plant, located on County Road 76 and Seventh Avenue Northeast.
The city’s Wellhead Protection Plan requires the abandoned wells be located as they may be potential contamination sources for public water systems. The city received an $8,300 grant from the Minnesota Department of Health for the project.
“This is a 10-year plan,” said Dwayne Heinen, assistant water supervisor in Little Falls. “It began in 2007 and will run until 2017.”
Heinen said Little Falls has been pumping water since the early 1900s and that the first water treatment plant, located in what is now City Hall, was built in the 1930s.
The new plant was erected in 1973.
“Before the water treatment plant, wells were dug and pumping stations were used,” he said. “City officials noticed manganese and iron in the water so the plant was built with a lime softening process.”
Heinen said that most wells were dug in the same vicinity as the plant because of the great aquifer under that spot. Those wells were used and rehabilitated until they got to the point of having to be abandoned.
“So no animal or other object could fall into the well, they were filled with dirt or gravel and capped,” Heinen said. “Huge semis spilling gasoline or oil as they drove past the wells was an unheard of occurrence in the 1920s. The city didn’t worry about the possible contamination of the water supply like it does today.”
Today, the Department of Health requires sealing all abandoned wells when not in use.
Through the Wellhead Protection Plan, the city hired 3D Geophysics Inc. who scanned the area around City Hall and the Water Treatment Plant, walking a grid with a GPS and a magnetometer to detect any anomalies in the earth.
“We have three known abandoned wells which were not able to be scanned because they are under buildings,” said Heinen. There is a list of nine others that need to have their location pinpointed.
Of those nine, eight areas scanned showed some type of anomaly in the ground, such as a well, and one didn’t show a positive report of anything being underground.
“We still have to check it out,” said Heinen.
The next step, he said, is to dig up the wells. The city chose the four easiest ones to start with. Ones that had no obstacles to contend with.
Well 7, next to City Hall, was a mere 3 inches underground, Installed in 1924, it is 12 inches in diameter and 88 feet deep. It had been filled with dirt and gravel.
“We first need to clean it out then will fill it with cement to cap it off,” said Heinen.
To seal the abandoned wells, they first must be cleaned out to 10 feet from the bottom of the well. Well 7 must be cleaned and filled a minimum of 78 feet down.
Well 11 is located between City Hall and County Road 76. There were no anomalies found by the magnetometer.
Well 12 is 6 inches in diameter and was located 13 feet underground. It is 89 feet deep and will have to be cleaned and sealed to a depth of 79 feet minimum.
Well 10 was listed as being in the basement of City Hall. It seems the area has many old pipes and cement which needs to be cleaned up before they can test for its correct location.
According to the Department of Health guidelines, a licensed company must be hired to seal the wells.
“Next year, we will be searching for more abandoned wells,” said Heinen.
“The administration is showing they are good stewards of the environment,” he said.