City faces costly fixes at wastewater facility

KINGMAN – The Kingman City Council faces an Aug.

16 state deadline for deciding how to improve the Hilltop Wastewater Facility.

City Manager Roger Swenson said a meeting in Phoenix with regulators did not open any new options.

Nitrates in the wastewater from Kingman sewer treatment facilities are red flags to the Arizona Department of Environmental Quality.

The wetlands process promoted by the department and used at the Hilltop facility since 1990 no longer meets state expectations, Kingman Public Works Director Jack Kramer said.

A monitoring well that checks wastewater leaving the facility shows nitrate levels of 13.7 parts per million.

The regulatory maximum is 10 parts per million.

The measurements are taken in a top-level or perched aquifer several hundred feet above the underlying aquifer from which city water is pumped, Kramer said.

The 400 feet of solid rock between the aquifers make no difference to regulators, he added.

Kramer estimates cost of improving the treatment plant at $10 million to $12 million.

The city will continue to pay $500,000 per year until 2012 on the original bonds for that facility, Kingman Financial Director Coral Loyd said.

State regulators have given the city until August to develop a solution proposal with a timeline for consultation and design and a proposed date for a city election to authorize financing, Kramer told the Kingman City Council.

The Arizona Water/Wastewater Infrastructure Finance Authority (WIFA) provides low-interest loans for water and wastewater projects.

The bonds are repaid by including a monthly fee in the bills of residents using the sewer system and must be approved by voters.

"Unfortunately, ADEQ is asking us to rebuild the Hilltop system before the original bonds are paid off," Kramer said.

The $2.6 million cost of replacing the Downtown Wastewater Plant has been in the city budget for two years in anticipation of a decision by state to shut it down.

A monitoring well just past the discharge end of the facility had produced nitrate levels above 10 parts per million.

At a meeting with ADEQ officials in Phoenix last week, Kramer and Kingman City Manager Roger Swenson learned that a monitoring well could be placed 750 feet downstream from the downtown plant.

ADEQ regulators hinted that nitrate levels might be low enough that far away.

A monitoring well would cost between $10,000 and $20,000.

Swenson called that a "good gamble."