A new documentary, "In the Dark of the Valley," focuses on the Santa Susana Field Laboratory, located just south of Simi Valley and the site of a nuclear meltdown in 1959.

One of the film subjects is Melissa Bumstead, whose daughter was diagnosed with a rare and aggressive form of leukemia at age 4. In an interview for "LA Times Today," Bumstead joined host Lisa McRee to share her story.

Bumstead said her mortgage paperwork had a small disclaimer regarding the Santa Susana Field Laboratory, and she was told that it was nothing to worry about.

"It was not until my daughter was diagnosed with a rare type of leukemia, and we kept meeting other families in treatment at children's hospitals, that we realized this was not a coincidence," Bumstead said. "Childhood cancer is just too rare."

According to Bumstead, an epidemiological report by the University of Michigan shows a 60% higher cancer indecent rate for people living two miles from the site.

"We also know that this area has a much higher breast cancer rate," she said. "Working with our own self-reported data and a statistician, we believe this community is also above average for many rare pediatric cancers. I think people who knew about the site assumed it was a Simi Valley problem, which is unfortunately not true due to natural erosion, rain runoff and the wind blowing through. This contamination is not kept in barrels buried in a vault underground. Most of it is in the groundwater and soil itself."

Bumstead said the Department of Toxic Substances Control is the government agency that should be regulating this cleanup.

"It was meant to be done in 2017, and the soil cleanup has not even begun. Boeing, NASA and the Department of Energy all signed legal agreements to clean up the site, and unfortunately, they are now trying to come out of those promises. Instead, they are proposing to leave as much as 98% of the contamination on-site permanently."

Bumstead eventually united with other mothers whose children were affected by the Santa Susana Field Laboratory, and they traveled to Washington, D.C. to seek help and answers.

"When we went to Washington, D.C., we were able to meet with our senators and congresspeople, and they have been huge supporters of the cleanup for years," Bumstead said. "However, when we met with the Department of Energy, we were told so many nice things, but no actions have been taken. That is something we see repeatedly: lots of words but no action."

Ever since Bumstead and other mothers raised awareness of their children's stories, the communities are coming together to support families affected by the Santa Susana Field Laboratory.

"There has been outrage building. Because of social media and the internet, people are coming together on our Facebook group, Parents Against Santa Susana Field Laboratory. We have over 4,000 local families who are incredibly concerned and want to see this cleaned up," Bumstead said.

Bumstead's daughter, Grace Ellen, managed to beat the cancer thanks to a bone marrow transplant.

"We are incredibly fortunate that she is a survivor, a two-time cancer survivor. So many people in our community were not very fortunate, and they had lost their children to cancer. But she is so strong-willed, active and energetic, and we finally feel like we got our Gracie back. I definitely feel like she appreciates the fact that she has a chance to live the rest of her life."

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