BERESFORD, S.D. | Driving on country back roads while hunting, Kevin Goeden has seen all sorts of things poking out of the banks along rivers and streams.
Decades ago, landowners would put old cars, farm machinery and other items along the banks to slow erosion. Seeing a wheel or car axle sticking out of a creek bank wouldn't necessarily set off alarms about possible foul play.
"It wouldn't be uncommon for those types of things to be found at or near a bridge site. I've seen it myself driving on county roads," said Goeden, chief bridge engineer with the South Dakota Department of Transportation.
It's one possible explanation for why a car found in the bank of Brule Creek just south of the bridge over 310th Street Monday remained undetected for so long.
Police believe the car, found by a passerby, is the 1960 Studebaker Lark in which Pamella Jackson and Cheryl Miller, both 17, of Vermillion, S.D., were last seen riding on May 29, 1971, on their way to a party at a nearby gravel pit.
On Tuesday, the car was pulled from the west bank of the creek, and authorities said skeletal remains were found inside. Remains were transported to a Sioux Falls laboratory Wednesday for testing.
"Hopefully the lab will shed some light on some things as far as identity," Union County Sheriff Dan Limoges said.
South Dakota Attorney General's Office spokeswoman Sara Rabern said no information on the remains will be released until a forensic exam of the remains has been completed. Rabern said it's not known how long the exam will take.
If the car had been in the Brule Creek bank for more than 42 years, it's hard to imagine no one seeing it during that time. But it's possible a portion of the car had been spotted in the past, and the person seeing it just assumed a farmer had placed it there to stabilize the creek bank, said Ray Roggow, Union County public works administrator.
"Something old sticking out of the bank, you wouldn't be too surprised," Roggow said. "There's probably places along the Sioux River you'd find old cars buried."
If the car was visible last summer and fall, bridge inspectors and county road workers didn't see it.
Every two years, the bridge has been inspected, most recently in August 2012. Goeden, whose agency does not inspect county bridges, said bridge inspections include some review of the channel for erosion, but the focus is on the structure.
Johnson Engineering, of Yankton, S.D., completed last year's inspection of the bridge near the spot where the car was found. Company President Dan Johnson declined to comment about inspection procedures.
Last fall, county workers removed debris hung up beneath the bridge. Roggow said he had talked to those workers this week to see what they remembered about the creek channel.
"I even asked the guys if they'd even seen anything, and they said no," Roggow said.
It's possible, Roggow said, that the car was hidden until this spring, when 7-11 inches of rain fell on the area during a May weekend and caused major flooding along Brule Creek.
"I'm thinking that flood this spring, I'm sure it had the ability to unearth some things. That water ran really, really hard through there," Roggow said. "There can be a thousand assumptions and speculations."
A South Dakota State Penitentiary inmate, David Lykken, of rural Alcester, S.D., was indicted on murder charges in the case in 2007. Those charges were dismissed after authorities learned that a jailhouse informant who claimed to have taped Lykken confessing to the alleged crimes had faked the recordings.
Officials have not said if Lykken remains a suspect in the case.
Journal reporter Molly Montag contributed to this report.