SIMI VALLEY, Calif. -- The sun was barely up at a former Cold War rocket test site when crews in hard hats, neon vests and steel-toe boots collected jars of dirt as part of a massive effort to clean up from a partial nuclear meltdown a half century ago.
Parties that inherited the toxic mess face a 2017 deadline to restore the sprawling hilltop complex on the outskirts of Los Angeles to its condition before chemical and radioactive wastes leached into the soil and groundwater.
For residents living downhill from the Santa Susana Field Laboratory, it would seem like a conclusion to a protracted fight. But many remain dissatisfied that a large portion of the land won't be cleaned to the highest standards.
"I don't care how long it takes, I just want it cleaned," said 62-year-old Holly Huff, whose family moved into the area a month before the 1959 nuclear accident.
The road to decontamination has been long and costly, as winding as the two-lane path to the lab entrance 30 miles northwest of downtown LA. Decades in the works, the cleanup has been complicated by the web of owners and responsible parties at the nearly 2,900-acre site.
Environmentalists and homeowners three years ago cheered when the U.S. Energy Department and NASA agreed to clean their parcels to background levels -- the most stringent standard -- essentially returning the land to its natural state.
But Boeing Co., which owns the lion's share, opted to follow cleanup rules drawn up in a 2007 pact requiring the site to be scrubbed to a lesser standard.
Despite the lower bar, Boeing said it's complying with cleanup expectations typical of Superfund sites. The defense contractor wants to transform its tainted section into a park and says it's doing more than necessary to meet that goal.
"We want to make planes, and that's our mission. We want to get this site cleaned up as quickly and as safely as possible," said Boeing project manager Art Lenox.
On a recent July morning, loud drills echoed from the Boeing section where workers fetched soil samples that were then transferred to stainless steel containers and placed in a cooler for later analysis.
In the area of the nuclear meltdown, another team used shovels to dig into the dirt like archaeologists. The goal: determine the amount of volatile organics, heavy metals and other possible carcinogens left from the rocket testing and nuclear age.
The work, expected to continue through the end of the year, is the prelude by the three parties to sketch out their final cleanup script, which should begin in 2016.
"We're doing everything we can to keep to a 2017 schedule. It will be a hard push," said Mark Malinowski of the California Department of Toxic Substances Control, which oversees the cleanup.
Meanwhile, state regulators are hoping Boeing will commit to a stricter cleanup standard by appealing a judge's decision that sided with the company.
Before Santa Susana became known as a polluted eyesore, it roared with the noise and glow of engine tests.
Founded in 1947 by North American Aviation, Santa Susana quickly became an aerospace hub. For four decades, workers tested thousands of rocket engines that later flew on missions that included Apollo. The site also hummed with nuclear research and was once home to 10 reactors.
In 1959, a reactor partially melted, belching radioactive gases. The reactor was shut down but later restarted. The government at the time said there was no dangerous radioactive release. Full details of the meltdown were not made public until two decades later by a group of University of California, Los Angeles, students.
In 1996, Boeing acquired the site when it bought Rockwell International Corp., which had merged with North American Aviation decades earlier. By the time the lab closed, it had left a noxious legacy.
Since the 1980s, NASA has spent about $100 million on cleanup and estimated it would cost another $250 million to $300 million to fully restore its section. The Energy Department has spent about $90 million in the past decade. Boeing declined to disclose its costs.
Some residents who have developed leukemia, breast cancer or serious thyroid conditions blame their health problems on their proximity to Santa Susana.
University of California, Santa Cruz lecturer and activist Dan Hirsch said residents want Boeing to clean its portion to the highest standards.
"This is not like trying to get to the moon," he said. "It's shovel work."
Earlier this month, Hirsch and other environmentalists sued the state, claiming that Boeing buildings were demolished and improperly shipped to landfills that were not licensed to take radioactive waste. The state has maintained that none of the torn-down buildings posed a threat.
Even if the bulk of contaminated soil is scooped up and hauled away, the groundwater problem persists. The state estimates it would take many decades to complete that part of the cleanup.
For residents like Huff, who was diagnosed with leukemia in 2009, the cleanup has dragged so long that she hopes there's no more drama.
"To be honest, sometimes I try not to think about it," she said. "It's just depressing."