EPHRATA - Grant County needs to drill wells to monitor groundwater coming from the fairgrounds.

Kevin Lindsey, a GSI Water Solutions' hydrogeologist, reported on the progress of the monitoring ordered by the state Department of Health. The department is requiring the county to get permits for the septic systems at the fairgrounds.

The commissioners and Lindsey hoped to test under the drain fields to discover whether moisture was leaking out of the system.

Lindsey said department officials wanted the groundwater tested because of regulatory requirements. The officials want to see little or no impact on the groundwater from the septic systems at the fairgrounds.

"They need to know what's going on in the groundwater so they can meet their objective," he said. "In my conversations with them, they are not fans of soil probes because their objective is groundwater."

Commissioner Carolann Swartz questioned the department's decision, saying if it didn't come out of the septic system, it's not going into the groundwater.

"I'd have to chase every septic system on site," Lindsey said. "They're willing for us not to look at every facility as long as we're looking in groundwater ... I think that they'll go with three or four monitoring wells and they don't want to look at the whole site. They want to look at one or two high-use facilities or high-use areas."

If the county can prove the high-use septic tanks aren't causing a problem, the department is willing to not require more from the county, he said. The project is likely to include drilling 4-inch wide and about 115-foot deep monitoring wells measuring the water running above the basalt. The county likely would need to construct a well north of the fairgrounds and one to three wells inside the fairgrounds targeting high-use areas. It's possible the wells could cost the county about $10,000 a piece.

"We basically got to get the first water and go about 10 to 15 feet in," Lindsey said. "There's no reason to go deeper. There's no precedent to go deeper."

It's unlikely they would reach water before 100 feet, he said. If they do, then they would stop and think about how to proceed.

The push to monitor the fairgrounds septic systems is likely because of a state Department of Ecology report from the early 2000s, he said. The report shows the Lewis Horn, which receives groundwater coming from the fairgrounds has the highest nitrate content in the lake.

"So everybody is looking around, trying to figure out what's going on," he said.

Swartz pointed out the area had farms and a Moses Lake park's septic system is located close to the shore of the lake.

"The Ecology study actually pointed to that facility as the problem, not to the fairgrounds," Lindsey said.

Commissioner Richard Stevens said the highest use system would be the holding tanks outside of the Ardell Pavilion, which are pumped out and shipped off site. The holding tanks contain the sewage from the campground sewage connections.

After Lindsey said he wanted to know what drain field is the most used, the commissioners agreed it would be the drain field near the rodeo arena, with the one near the entrance being a distant second.

Lindsey and Department of Health officials are likely to discuss where to place the wells within a month, he said. The placement needs to be decided ahead of a March deadline to submit a groundwater monitoring plan.

"I think that's key," Swartz said. "I think all of the interested parties need to buy into that before we even touch a drill."

It's likely the plan will call for two years of monitoring every quarter, Lindsey said.