The Tooele County Board of Health discussed the possibility of allowing conventional septic tank systems for minor subdivisions in Erda on a case-by-case basis during a meeting Wednesday.
“Too many septic tanks too close together is not good,” said Tooele County Health Director Jeff Coombs.
He said one possibility would be for the board to judge each proposal for conventional septic tank systems on smaller lots on a case-by-case basis.
“Whether it would be allowed would be based on the nitrate load in the area where the septic tank was proposed,” Coombs said.
The health board’s current policy, adopted in September 2017, allows for only one conventional septic tank per five-acre lot. The intent was to help improve the quality of groundwater and eliminate high concentrations of nitrates detected in some areas of Erda, according to Bryan Slade, county environmental health director.
On Wednesday night, the board rejected a proposal from health department staff to allow individual property owners to divide their property into one-acre lots and allow conventional septic tanks on those lots.
Board member David Rupp said he did not see how allowing exceptions for conventional septic tanks on one-acre lots helped with the overall health department goal of providing for clean water.
“Our concern is too many septic tanks,” Rupp said. “I don’t see any merit in this exception proposal for one-acre lots.”
The board tabled the one-acre option, and plans to further discuss the issue at its next board meeting in May.
Possible options included limiting conventional septic tanks to 2.5-acre lots, or allowing them on a case-by-case basis depending on the water quality in the area where a proposed septic tank is planned.
Coombs said the five-acre septic tank regulation has helped to stop large development proposals in Erda.
“We had four or five developers who were proposing anywhere from 20 to 200 lot subdivisions that ranged in lot size from one-quarter acre to one acre. The septic tank rule prevented them from moving forward,” Coombs said.
“However, there are circumstances where a single lot being split off from a larger lot would not have a high impact on water quality,” he said.
Which, Coombs said, was the reason for providing an exception to the five-acre rule. He said in the past two years there have been no more than five cases where families have wanted to subdivide five-acre lots and put in septic tanks.
“Not many are wanting to split off one acre at a time,” he said.
Slade said in a previous board meeting that the U.S. Environmental Protection Agency set the nitrate level as too high at 10 parts per million. He said the water discharged in the bench areas of Erda is pristine with less than 1 part per million nitrates, but some private wells in Erda were reaching 5 parts per million in nitrate level.
Slade said most of Stanbury Park’s water comes from wells in Erda, and Stansbury Park officials are willing to eventually handle Erda’s wastewater to protect their own water quality in the future.
The board would like to see more alternate septic systems with filters and pumps that help clean the water before it is discharged into the ground. However, those systems cost $15,000 compared to $5,000 for a conventional system.
In May 2017, a South Jordan company that specializes in water quality conducted a septic tank system study in unincorporated Tooele Valley. Hansen, Allen & Luce, Inc. recommended a minimum of five-acre lots for each septic system. The company’s recommendation was based on solid science, Slade said.
The health department requested the study because of a high level of nitrates found in some wells in Erda, according to Slade.
Nitrate is a pollutant that comes from fertilizer use, traditional septic tank soil-absorption systems, sewage and erosion of natural deposits. Drinking water that contains more than 10 milligrams of nitrate per liter of water can cause infants to become ill, such as with baby-blue syndrome, according to the EPA.