YAKIMA, Wash. -- Yakima County Treasurer Ilene Thomson is still working to clean up the mess left when a Key Bank error early last month caused a large number of county payment checks to bounce.

About 225 of the checks, referred to in government parlance as warrants, were returned to those who cashed them as being drawn on an account with insufficient funds.

Thomson said the bank quickly corrected the error, which was discovered on June 4, and the county was never short of money.

"I can guarantee you we have $250 million in investments and we aren't broke," she said.

But she agreed it doesn't look good for checks issued by the county to appear to be rubber.

The checks were issued to vendors who provided services to the county or other local governments for which the county provides financial services, as well as county employees, and some private citizens. Some of the payments were to county employees as expense reimbursement and to citizens for jury duty.

Thomson said about 20 of the checks remain outstanding.

A Key Bank official, senior vice president Kim Monson of Bellevue, Wash., said she could not comment on the problem because of customer privacy issues.

Thomson said the bank is trying to reach all of the recipients and will pay all fees incurred as a result of the error.

How the error occurred remains unclear.

Thomson's office provides financial services to a variety of units of government such as the county, school districts, fire districts and others.

She said procedures require her office to leave enough money in the general bank account each night to cover all warrants expected to be redeemed prior to the next business day.

At the first of the month, the general account will clear warrants of as much as $8 million.

Even if her office misjudged the amount needed, the four-year agreement with Key Bank for banking services requires the bank to honor all warrants, she said.

Thomson said she is being philosophical about the error.

"These things happen. I think the bank inadvertently overdrafted these warrants and returned them," she said.

* David Lester can be reached at 509-577-7674 or dlester@yakimaherald.com.