Skagit County authorities found 54 dead cattle on a farm with a history of complaints. A sheriff's department drone spotted the cows in what neighbor Kevin Gaegon has called a "killing field."

For Gaegon, the sheriff's drone investigation was 13 years in the making.

"It's a glorious day for everyone," he said, tears welling up in his eyes.

Gaegon first reported dead cows being illegally discarded on the Bayview neighborhood ranch in 2005.

At that time, officials found 172 dead cattle littering the farm owned by Roger Pederson.

Pederson was cited and sentenced to probation, but the mistreatment of his animals apparently didn't stop.

Gaegon complained again in 2009. KING 5 cameras spotted at least one carcass rotting in waters that lead to nearby Padilla Bay, posing a serious public health risk.

Last week, Gaegon captured video of a front loader dumping even more remains.

Then authorities discovered another 54 dead cattle this week, plus one living in cruel conditions.

"We had to actually euthanize one yesterday," said Skagit County Chief Deputy Chad Clark. "It looked like it was being eaten by a coyote and was still alive."

Veterinarians helped identify the sickest of the approximately 200 remaining animals. An estimated 20 to 40 of them were taken to farms where they will be nursed back to health.

It's unclear how these latest cattle died, but the suspicion is they were malnourished and neglected.

Over the past 13 years, county officials have been heavily criticized for not doing enough to stop the slaughter.

When KING 5 News inquired about the situation on Monday, Skagit County Health Department official Joanne Lynn said, "I intend to make sure this behavior stops. We will not tolerate it."

She kept her word, and more than a decade after starting down this road, Kevin Gaegon is relieved.

"My confidence level wasn't real high just because of the history," he said. "I'm glad it's being done. 13 years was not for nothing."

Chief Deputy Clark said Pederson could potentially face animal cruelty charges, a Class C felony.