CHANGE OF HEART.- If city can prove this method is the best treatment option, state may allow it
By Sharon Michael, The Chronicle, 7/28/98
State Department of Ecology officials have agreed to allow the city of Chehalis to "consider" alternative treatment options, including in-river aeration that could improve dissolved oxygen levels in the Chehalis River.
Dissolved oxygen is required to sustain fish and other aquatic life. Natural levels of dissolved oxygen are below state and federal water quality standards in the river's slow-moving Centralia Reach, where the city now discharges treated wastewater.
To prevent further degradation of water quality, the city has been prohibited from discharging wastewater into the Reach during low flow periods - usually from May to October.
Public Utilities Director Barry Heid says adding oxygen to the river through aeration could increase dissolved oxygen levels to state and federal standards. Additional treatment, coupled with improved oxygen levels, could allow discharge into the Reach during low-flow periods without degrading water quality.
UNTIL RECENTLY, Ecology has refused to allow Chehalis to consider aeration as a means of meeting wastewater discharge permit conditions.
"We will not allow aeration in the river in place of treatment," Kahle Jennings, Ecology's regional water quality specialist, told Chehalis Basin Partnership members last month.
Jennings said then that state and federal regulations would not allow Ecology to permit in-river aeration.
After Mayor Bob Spahr testified July 7 before the House Agriculture and Ecology Committee, Ecology director Tom Fitzsimmons agreed the agency would take another look at the city's request.
Last week Megan White, Ecology's water quality manager, notified Spahr that the agency had reconsidered its position.
"We will consider it," Jennings confirmed on Monday.
That doesn't mean Ecology will approve aeration, he added. But he acknowledged Ecology's position changed recently.
"Before, we didn't think we wanted to consider (aeration)," he said, primarily because it uses the river as part of the treatment system.
BUT JENNINGS said Ecology has reevaluated Chehalis' request, and has determined that federal guidelines do allow aeration under certain conditions.
White said Chehalis must be able to "demonstrate that aeration provides the highest environmental and economic benefit."
"We don't want to do it unless it makes economic, environmental and engineering sense," said Heid.
Heid called Ecology's position change "a big step in the right direction
He said it signals a willingness on the part of Ecology to work cooperatively with the city.
"We're pretty happy about the change in attitude and cooperation," Spahr said.
Before Chehalis would be allowed to choose aeration as its preferred option for meeting wastewater discharge permit conditions, White said, the city must first evaluate all wastewater treatment and reuse options.
"Treatment of wastewater for beneficial reuse is a legislative and Ecology priority," White said. "This, combined with the fact that the upper Chehalis Basin is closed to further water appropriation, means that wastewater treatment options such as reuse for industrial purposes, groundwater recharge, or streamflow augmentation should receive the highest priority by Chehalis."
White suggested "aeration might be an appropriate interim solution until a market for reused water develops."
SPAHR AND HEID are pleased the city will be allowed to explore other, less expensive alternatives to piping wastewater discharge downstream of the Skookumchuck River for discharge. The consent decree just signed by Spahr gives the city eight years to meet new wastewater discharge pen-nit conditions.
Evaluation of aeration will be part of the city's general sewer and facilities studies now in progress. Those studies also are required by the consent decree that settles a lawsuit Chehalis, Centralia and Darigold Inc. brought against Ecology over wastewater-discharge permit conditions.
"Nothing in here is unanticipated," Heid said of conditions for in-river aeration outlined by White. Among those conditions are:
A complete review of all best available treatment technology.
A complete state environmental policy act review.
A requirement that other interested parties, including the Chehalis Confederated Tribes and the state Department of Fish and Wildlife, review and accept the city's proposed alternative.
A perpetual maintenance and monitoring agreement, and a bonding requirement.
Public involvement.
THE CITY ALSO COULD be required to pay for developing computer modeling used to justify aeration.
Heid said aeration is just one option at which the city is looking to meet wastewater discharge pen-nit conditions, and it may find aeration is not the best alternative. But he is pleased Chehalis can now study that option, as well as other alternatives.
White said before aeration could be approved as the "preferred environmental and economic solution," the U.S. Environmental Protection Agency would first need to review the city's proposal and approve a revised study of the river's capacity to absorb wastewater discharge without degrading water quality.
Ecology could not predict the outcome of EPA's review, White said.
But Ecology would not support an alternative that increases the city's waste-load allocation at other dischargers' expense, she warned.
Sharon Michael covers Centralia and Chehalis city governments for The Chronicle. She can be reached by E-mail at smichael@chronline.com or by calling 807-8237.