Elk Mound could face phosphorus problems, too

By LeAnn R. Ralph

ELK MOUND — It’s not just Colfax with problems related to phosphorus discharge from the wastewater treatment facility.

The Elk Mound Village Board learned at the November 7 meeting that the village could be in a position of having to comply with the new phosphorus discharge requirements.

Paul Gont, a wastewater engineer with the consulting firm of Short, Elliott and Hendrickson (SEH), spoke to the village board about copper and phosphorus requirements.

Elk Mound also has had some problems with copper in the wastewater discharge.

Phosphorus is the nutrient implicated in toxic algae blooms in area lakes, and copper is toxic to micro-organisms that are part of the food chain in a wetland.

Elk Mound’s wastewater treatment facility discharges directly and continuously to a wetland.

Elk Mound’s wastewater treatment permit expires next year on June 30, and the village must reapply for another permit by December 31 of this year, Gont said.

DNR wastewater permits are issued for five years.

After Elk Mound has applied for a new permit, the state Department of Natural Resources will issue a draft permit, will publish a public notice, and will then set a 30-day comment period, Gont said.

After the final permit is issued, the village will have 60 days to contest any of the requirements. If the requirements are contested, the permit would go to a contested case hearing, he explained.

With the new phosphorus requirements, some communities are contesting their permits, Gont noted.

“Now we’ll have to wait and see what happens,” he said.

Inspection

DNR officials conducted a wastewater facility inspection in Elk Mound on October 3 of this year.

A letter from the DNR states that Elk Mound’s wastewater treatment facility is “in compliance,” said Terry Stamm, director of public works.

The inspection identified one area related to sampling, but that has been corrected, Gont said.

The existing wastewater treatment facility is operating well, he said.

Unfortunately, Elk Mound’s wastewater treatment facility is not designed to deal with the new phosphorus requirements, he said.

“The plant is performing well for conventional nutrients,” Gont said.

Copper

Over the last couple of permit cycles, Elk Mound has applied for and received a variance on the copper discharge requirements, Gont said.

Sources of copper in the wastewater can include rain water infiltration of the sewer lines; corrosion of copper pipes in houses; food waste and industrial uses, such as copper wires and boilers.

The softer the water, the more toxic the copper, Gont said.

Elk Mound has moderately hard water, he noted.

The DNR protocol requires reviewing the sources of copper, treating the sources and making the water less acid so that it does not leach copper from the pipes, Gont said.

After all of the steps have been taken to identify and mitigate copper sources, the DNR will issue a variance, he said.

During the last permit cycle, Elk Mound increased the chlorine in the water system, “but it did not make much of a difference,” Gont said.

Phosphorus

Under the old rules, Elk Mound did not have to remove any phosphorus from the wastewater discharge.

Elk Mound’s raw sewage currently contains between five and seven parts-per-million of phosphorus. Thirty years ago, the amount was ten parts per million.

The reduction in phosphorus is due to the control of cleaners and soaps containing phosphorus, Gont noted.

According to the old rules prior to 2010, there was no requirement for small discharges of 150 pounds of phosphorus per month, he said.

The new rules require .1 parts per million of phosphorus for a river, while small streams have a limit of .075 parts per million, Gont said.

Lakes and flowages are set even lower at point .04 parts per million, he said.

Wetlands have no phosphorus limit unless waterways are impacted downstream, Gont said.

Wetland

Elk Mound currently discharges to a wetland that eventually drains to Muddy Creek, which in turn drains to the Chippewa River.

Stamm and Gont said they had walked the wetland area with representatives from the DNR.

Because of the dry conditions this year, the wetland is fairly dry, the vegetation has grown up and there is no channelized stream, Gont said.

There are indications, however, that the DNR will declare that a flow of water through a culvert under I-94 is part of the discharge, he said.

If the stream is in compliance with the regulations, Elk Mound has no phosphorus worries, Gont said.

If the stream is over .075, the next question is whether it is the Elk Mound discharge that has brought the level up, or it from other sources, he said.

“Much will depend on the DNR’s test results,” Gont said.

If Elk Mound ends up being required to reduce phosphorus, the DNR will devise a compliance schedule. The first step will be an “optimization report” to look at the wastewater treatment plant to see what can be done without spending any money, he said.

Elk Mound has no large industry, but there are other sources of phosphorus that could be considered, Gont said.

The next step would be a facilities plan to figure out how to comply with the lower phosphorus limit, he said.

The federal Environmental Protection Agency is pushing the DNR to impose strict phosphorus limits to bring the state’s waterways into compliance with federal requirements for the Clean Water Act, Gont said.

This is the first five-year cycle for wastewater permits, and the compliance schedules are expected to stretch out over seven to nine years, he said.

“Getting down to those very low levels is very difficult. It’s new territory,” Gont said.

Options

Some options for Elk Mound to reduce phosphorus discharge could also include mechanical and chemical removal of the phosphorus.

The village could also discharge to a different stream that has better limits, if another stream is available.

Elk Mound could do land disposal, too, except then nitrogen becomes a problem, Gont said.

On the other hand, Elk Mound’s wastewater treatment plant already is removing nitrogen well, he said.

Pollutant trading with area farmers also could be a possibility, Gont said.

The farm fields to the west of the wetland could be affecting Elk Mound’s phosphorus levels, he said.

“We need to look for the most economically feasible compliance,” Gont said.

Other municipalities are using the wastewater to make concrete blocks or for irrigating a crop or for the processing of sand mined in the area, he said.

Unfortunately, using the wastewater to wash sand presents problems elsewhere. The sand, which is now higher in phosphorus after being washed with wastewater, is injected underground and then contaminates the groundwater with phosphorus around the oil and natural gas wells, Gont said.

An economic variance is available, too, but the sewer rate must be more than two percent of the median household income, he said.

For example, if the median household income in Elk Mound were $50,000, the sewer rate would have to be more than $1,000 per year, or more than $83 per month, or more than $250 per quarter.

Within the next few months, the Elk Mound Village Board will have to make decisions on options, Stamm said.

Other business

In other business, the Elk Mound Village Board:

• Set the next meeting for Tuesday, November 20. The regular meeting date of November 21 is the night before Thanksgiving, and several village board members are planning on being out of town.

• Decided not to take any action on sewer standby fees that are currently set at $8 per year. The Public Service Commission of Wisconsin requires municipalities to set standby fees for properties that are not developed but that are served by sewer and water lines. Elk Mound has ten services on standby.