‘In the Dark of the Valley’: Why is there still no clean-up of 1959 nuclear meltdown at Santa Susana?

Written by Danielle Chiriguayo, produced by Christian Bordal and Kathryn Barnes

A battle has raged for decades on the western edge of Los Angeles County at the Santa Susana Field Lab. Located on the top of a hill overlooking Chatsworth, Simi Valley, and Canoga Park. From 1948 until 2006, it was a nuclear testing site for America’s space exploration programs — home to 10 nuclear reactors, four launch stands, and thousands of tests of rocket engines. It also suffered a partial nuclear meltdown — which was covered up — that released clouds of radiation into the surrounding area.

In the decades since, arguments have dragged on about how to clean up the contaminated site and who will pay for it. The saga at Santa Susana is the focus of a new documentary called “In the Dark of the Valley.” 

KCRW talks with director Nicholas Mihm and two people in the film — Melissa Bumstead, who lives near the site, and KNBC-4’s investigative reporter Joel Grover, who’s been following the story for the last six years. 

The following interview has been edited for length and clarity. 

KCRW: Nicholas, how did you learn about Santa Susana, and what made you want to make this documentary? 

Nicholas Nihm: My producing partners and I first stumbled upon this story in 2018. I think it was January or February of 2018 when we were hired by change.org to do a two-to-four minute video for Melissa's petition. And that really introduced us to the subject and we quickly realized when we were making that little petition video, that this story was much too large for two-to-four minutes. So we convinced Change.org to do a seven-minute video. And obviously that's still not enough time to fit the story. And so after we completed that project, we quite separately from Change.org decided to venture into the feature documentary world and started the journey from there.

Melissa, you’ve been fighting for this cleanup since your daughter Grace was diagnosed with an aggressive form of leukemia. Talk about the connection you believe exists between Santa Susana and the cancers in your community. 

Melissa Bumstead: When we first found out about Grace's diagnosis in 2014, we were told that there were no environmental links between pediatric cancers and contamination or really anything. That it was just a genetic fluke. And of course, we don't question our doctors and that seemed very reasonable. It wasn't until we started meeting other families at Children's Hospital Los Angeles that I started to question that. We met a family — Lauren Hammersley and her family who are in the documentary.  They live only probably 10 miles on the other side of the mountain. And then I met another family who lived two blocks over. And I met another family who was two blocks over and a little bit over to the east. 

And finally, when I met another family who lived on our avenue, I started to panic because I knew that childhood cancer is extremely rare. There's only 15,000 new cases every year out of 72 million children in America. So the chance of knowing your neighbors especially at an internationally renowned hospital, like Children's Hospital Los Angeles, we knew something wasn't right. We've mapped ourselves on Google Maps, and we all saw that we were in this big circle. It wasn't until about a year later that someone first said that the Santa Susana Field Lab [was] right there in the middle. Do you think it could be the contamination?

Melissa Bumstead is with her daughter Grace, who suffers from a rare form of leukemia. Photo by MSNBC Films.

Did other families impacted by these rare cancers know they were living close to Santa Susana? 

Bumstead: You know, I've lived within probably 20 miles of the Santa Susana Field Lab my whole life, but I didn't learn that it actually existed until my daughter's cancer. Nobody ever mentioned [it] when I was 18, and I had a rare autoimmune disease called ITP. And I actually had a mutant spleen. I had three spleens, the doctor said they've never seen anything like that before. Nobody mentioned contamination or radioactive fallout or anything. When my mom had a brain tumor at age 40, they didn't say anything. When she grew up in the area and had tumors all over her gums that they had to take off when she was eight, nobody ever correlated the Santa Susana Field Lab and the health issues. 

And I think for a long time, everyone assumed it was just bad luck, that their family was unlucky. For me, what really convinced me that this was absolutely a problem was when I learned about the epidemiological study by Dr. Hal Morgenstern that found that residents living within two miles of the Santa Susana Field Lab actually had a 60% higher cancer incidence rate and that over 1500 workers have been diagnosed with cancer just from the Santa Susana Field Lab.

Have radiation readings been taken in populated areas around the West San Fernando Valley? Near your home, for example. Are levels higher there? 

Bumstead: They've done extensive studies on the field lab. When it comes off of the field lab, it gets a little trickier. Actually, the headwaters of the Los Angeles River are at the Santa Susana Field Lab. And so every time that Boeing lets contamination from the field lab get into the water, they're often fined. Or they're actually not fined. The Water Board almost always lets them off. [But] they have to account for that contamination. And so after the Woolsey Fire, we saw things like lead 14 times above the legal level. We saw cyanide, and arsenic and mercury, all these dangerous heavy metals and different chemicals. So we know that these things are coming off the mountain into the community. 

Ours is not very static, it's very mobile contamination. It can blow into your yard one day and blow out the next day. But I think that's what's made this site so tricky. Because some days it is hard to measure, and it's no mistake that Boeing only takes the water runoff readings during the summer when there's no runoff. We see that consistently, that type of poor testing. Things to minimize the danger. We even know actually from one of Boeing's own studies  — they hid it in the footnotes — according to their own data, certain parts of the lab are so contaminated that 96 out of 100 people would get cancer, if they lived on the site, and they grew produce and they ate it. 

KCRW reached out to Boeing for their comments on these allegations and they declined an interview. They also declined an interview in the documentary. Joel, have you tried contacting Boeing? 

Joel Grover: When you say they declined an interview, I have been trying for at least six years to sit down with Boeing, and ask questions about Santa Susanna and the contamination there. And they have always declined an interview. But let's not single out just Boeing. There's NASA. There's the U.S. Department of Energy (DOE). There's the Department of Toxic Substances Control, the state agency that's supposed to protect us from toxic substances. They do not want to answer reporters' questions. And I've been an investigative reporter for 30 years and I have often noticed that if someone doesn't want to sit and answer your questions, maybe they have something to hide.

Joel Grover, investigative reporter at KNBC-4, has been reporting on Santa Susana since 2015. Photo by MSNBC Films.

The Department of Energy and NASA signed a legal agreement in 2010 to clean up all this contamination to background levels.

Grover: Background levels are the level of radiation that naturally occurs in the soil when nothing is there. 

Clean-up was supposed to be done by 2017. But here we are four years later. 

Grover: Well, let's go back even before 2017. These agreements were signed in 2007 by Boeing, by NASA, by DOE. And I always found this interesting. It was a Republican governor of California, Arnold Schwarzenegger, whose administration got those agreements signed. And his administration really pushed for a full cleanup of Santa Susana, and subsequent administrations, governors, have let those agreements basically slide.

Isn’t the agreement legally binding? 

Grover: There are ways that a government agency or private company can prolong the process, saying ‘We need a new environmental impact statement.’ There's a lot of ways they can postpone a cleanup. And there are those that have said to me, ‘The parties that should be cleaning this up are just trying to drag this out until no one remembers Santa Susanna anymore.’ But people like Melissa say, ‘Wait a minute. We're not gonna let people forget about this.’

Governor Gavin Newsom appointed Jared Blumenfeld as the head of the California Environmental Protection Agency in 2019. He spoke out publicly about enforcing the agreement and changing the culture at the Department of Toxic Substances Control (DTSC). Melissa, has he gotten closer to fulfilling promises? 

Bumstead: It's one of my biggest heartbreaks because I had so much hope and so much faith in Secretary Jared Blumenfeld. We don't know what politics are at play. But right now, as we speak, the Department of Toxic Substance Control and Boeing are in closed-door negotiations to completely gut the cleanup. We were having meetings with Blumenfeld regularly. We were having very productive meetings. And then all of a sudden, it was like he slammed the door in our face. 

And in fact, there's not any community representative at all in these negotiations between the DTSC and Boeing. Ventura County Supervisor Linda Parks, who has been a great advocate for the cleanup, requested to send a representative to these meetings and was denied. And Congressman [Brad] Sherman and Congresswoman [Julia] Brownley, they've been very proactive to try to make sure that the community doesn't get left out of this. And so now we're asking people in California to go above Blumenfeld and go straight to Governor Newsom and ask him to intervene to stop these negotiations. Because Governor Newsom right now is probably the only person who could stop this negotiation and put the cleanup back on track.

Melissa Bumstead shaved her head in solidarity with her daughter Grace, who lost her hair during chemotherapy. Photo by MSNBC Films.

Melissa, you said Blumenfeld was in discussions with Boeing to gut the clean-up agreement. How do you know that? 

Bumstead: Boeing hasn't kept it secret that they've wanted to get out of the cleanup agreements. All three players have made it very public that they do not intend to keep their original cleanup agreements. NASA came out with their final environmental impact statement saying that they would leave up to 80% of the contamination on-site permanently. When we met with California Senator [Henry] Stern he told us that Boeing made it known to him that they were entering into confidential agreements with the DTSC. 

Because of that, we've tried to do several FOIA requests, trying to get information for what these agreements might entail, and we've been blocked on every level because now these negotiations are considered private and protected. So to what degree they'll come out gutting the cleanup, we're not 100% sure, but we have a feeling it'll look very similar to their prior attempts, which have been to leave as much contamination as humanly possible. And then, just to add insult to injury to turn it into a public park.

Melissa Bumstead is an activist fighting for Santa Susana to get cleaned up. Photo by MSNBC Films.

KCRW also reached out to the U.S. Department of Energy and NASA. Both declined interviews. Joel, you mentioned some suspicious relationships between the responsible parties and the state agencies that are meant to regulate them. 

Grover: From my years of reporting on this, there is a documented history of a lot going on behind closed doors, including Boeing, I believe to stop a full cleanup of Santa Susana. I remember in 2015, I interviewed Jared Blumenfeld’s predecessor, Linda Adams, who was the California EPA chief under Schwarzenegger. And I remember her telling me, she called for a meeting with Boeing to discuss how to reach an agreement to get a full cleanup of Santa Susanna. And she said, when she had that meeting, the room was full of, ‘an army of Boeing lobbyists’ that she felt was meant to put pressure on her.

I remember Sheila Kuehl, who is now an LA County Supervisor, but was in the State Senate pushing for a full cleanup of Santa Susanna. I remember Sheila Kuehl telling me, whenever she had meetings about this, she would be surrounded by Boeing lobbyists pushing for less than a full cleanup. So from the politicians who have pushed for a comprehensive cleanup, they've always told me that they face a lot of pressure from Boeing and other parties to scuttle a full cleanup.

Nicholas, what would you ask these parties to set the record straight? 

Mihm: We did reach out to all these entities as well. Some of them did respond to us and politely declined, and Boeing was the only one who just didn't respond to us at all. And it would be great to get them in the room because I think what we really want to understand is, what the delay is and what their end goal is. Because it’s been weird to me, throughout these last few years making this documentary seeing the discrepancies and inconsistencies. 

In the film, we have former Secretary of Energy Rick Perry talking about how the Department of Energy found less contamination in further studies and therefore needed to adjust their cleanup standards. But you have a 2019 Inspector General's report issued by NASA that says in plain English, we've actually found more contamination. So I guess, with that being said, like if I got these people in a room, I would love to just ask them about those discrepancies.


KCRW reached out to Boeing, NASA, the National Department of Energy, the California EPA, and the California Department of Toxic Substances Control. All of them declined our requests to answer questions on the air. But some of them provided the following statements:

The Boeing Company:

Boeing and the State of California have agreed to pursue mediation as a tool to attempt to accelerate resolution of a pending dispute and commencement of site cleanup. The transformation of Boeing’s land at Santa Susana from a field laboratory to open space is well underway. Native plants and animals are reclaiming many of the previously developed areas of the property and the community is protected through the investigation, cleanup and monitoring activities.

Boeing has already conducted significant remediation work in support of site cleanup, including numerous interim cleanup actions.  The continued cleanup work will be one of Boeing’s largest environmental investments, and all work will be conducted under the oversight and at the direction of the State of California, consistent with applicable law and regulations, and to levels protective of future onsite users and the surrounding community.   

The U.S. Department of Energy:

The Department of Energy (DOE), and its Office of Environmental Management take public health seriously and share the same goal as local community members: To complete the safe cleanup of the environmental legacy that resulted from research supporting Cold War-era nuclear energy and space programs.

DOE is responsible for cleanup of Area IV of the Santa Susana Field Laboratory (SSFL), which housed the former Energy Technology Engineering Center (ETEC). DOE will continue to work with the state of California towards completion of cleanup in a manner that is protective of human health and the environment. The Department’s recent completion of building demolition at the ETEC site reflects our strong and continuing commitment to this mission. 


NASA remains firmly committed to achieving a cleanup at Santa Susana Field Laboratory that is protective of public health and the environment, preserves and protects the site’s important biological and cultural resources, and is based in science. NASA is to begin our final soil and groundwater cleanup activities as soon as the Department of Toxic Substances Control completes their environmental review process under California Environmental Quality Act and approves NASA’s cleanup plans.  

NASA also responded to KCRW’s question: Why has this taken so long? What is the holdup to making progress?

NASA wants to clean up Santa Susana as soon as possible and remains firmly committed to doing so. The health and safety of the community is our priority. We can begin official cleanup once the California Department of Toxic Substances Control (DTSC) completes their environmental review process under California Environmental Quality Act and approves NASA’s cleanup plans. 


When NASA signed the Administrative Order of Consent (AOC) in 2010, it did so prior to the DTSC establishing associated look-up table values, which are the levels that soil has to be cleaned to. NASA signed the order in good faith and with the expectation that DTSC would use sound regulatory discretion to develop a soil remediation methodology that uses well accepted, practical, implementable and feasible standards.  

Instead, the look-up table values established by DTSC in 2013—nearly three years after the AOC was signed—were created on the capabilities of laboratory equipment and not based on known risks to human health and the environment. DTSC’s look-up table values are much stricter than any other cleanup standard applied by DTSC in California—values that can’t even be met even by store-bought topsoil. Even DTSC recognizes and has documented problems implementing an AOC cleanup using the current look-up table values.

Due to the extremely low cleanup levels, onsite treatment technologies are largely not effective, requiring soil to be excavated and transported offsite for disposal. As a result, the soil cleanup described in DTSC’s Draft Programmatic Environmental Impact Report (PEIR), released in 2017, showed substantially greater soil removal than original estimates. In addition, the PEIR showed the cleanup would have significant impacts on the biological, ecological, and cultural resources at the site.

National Environmental Policy Act (NEPA) regulations require that when significant new information exists that is relevant to environmental concerns, agencies must complete a Supplemental Environmental Impact Statement (SEIS). NASA completed its SEIS in 2020. As required by NEPA, the SEIS looked at all reasonable cleanup options and how cleanup could best protect public health, as well as the environmental and biological resources at the site. Santa Susana is one of the last remaining wildlife corridors in the Los Angeles area, and home to many animal and plant species. The site also contains Native American cave paintings thousands of years old, and archeological and cultural sites.

NASA issued a Record of Decision in 2020 for a Suburban Residential Cleanup based on our findings in the SEIS. A Suburban Residential Cleanup achieves a cleanup that fully protects public health and is consistent with risk-based cleanup standards applied by DTSC throughout the State of California and is the standard Environmental Protection Agency (EPA) cleanup approach for sites across the nation. In addition, it would allow for more in-situ soil treatment options, reducing the amount of soil that would be required to be hauled offsite.

A Suburban Residential cleanup would take eight years to complete, versus an estimated 25-years with an AOC cleanup. As a result, it would significantly reduce the traffic impacts on surrounding communities and cause far less damage to the ecological, natural, and cultural resources. An AOC cleanup would require significantly more soil removal than a Suburban Residential cleanup for no additional protection to human health or the environment, and much more backfill is required to replace excavated soil and support native revegetation and habitat restoration. The only material available for backfill in such a quantity is a mix of sand and gravel, which would devastate the ecology onsite, local plant life, geology in the region, and alter water resources in unforeseeable ways. There is no soil available that meets AOC look-up table values, and doubtful enough gravel backfill material that meets those values in large enough quantities to replace the total volume of soil that will be excavated in pursuit of an AOC cleanup. 

The majority of soil contamination is concentrated in the operational source areas and decreases with distance from the source. A Suburban Residential Cleanup would remove all the soil contamination that could pose a threat to human health by targeting source areas where the contamination is highest. It would remove about 90% as much contamination as the AOC cleanup, yet require 70% less soil to be excavated and transported offsite, preserving the site’s cultural resources and the natural habitat, while still protecting human health. The trace amounts of contaminants left behind (that 10%) would be at such low levels that they would not be considered a risk to public health by the DTSC anywhere in California, or by the EPA anywhere in the nation. 

NASA is ready to begin and finish this cleanup. We are eagerly waiting for DTSC to complete their environmental review process under the California Environmental Quality Act and approve NASA’s cleanup plans so that we can start the final soil and groundwater cleanup activities at Santa Susana. 

Melissa Bumstead and the Parents Against the Santa Susana Field Lab had the following response to NASA’s statement:

NASA is, “looking for excuses to not fulfill the legally binding promises it made to undo” the damage that its presence has caused at Santa Susana. 

Parents Against the Santa Susana Field Lab say that the agreement NASA signed in 2010 — known as the “AOC” — requires it to restore the area to “background level”: the natural level of contamination that existed before NASA arrived. 

They further contend that, “There is no ‘new information’...The ‘Lookup Tables’ NASA refers to are based on the same measurements to determine ‘background’ that were required in the AOC cleanup agreement.” They suggest that NASA’s current position is an effort to “get out of the cleanup it solemnly agreed to eleven years ago.”