Mike Partain didn’t believe the rumors about a place called Baby Heaven until he visited a Jacksonville, N.C., graveyard and wandered into a section where newborns were laid to rest.

Surrounded by hundreds of tiny marble headstones, he started to cry. A documentary film crew that followed him for a story about water contamination at Camp Lejeune heard his whimpers through a microphone clipped to his clothes. The crew dashed from another part of the graveyard and found him asking, “Why them and not me?”

The scene at Jacksonville City Cemetery is among the more poignant moments in the documentary “Semper Fi: Always Faithful,” about the men, women and children affected over three decades by contaminated water at the nation’s largest Marine base. The film made the short list of 15 documentary features being considered for an Oscar; the Academy of Motion Picture Arts and Sciences will cut the list to five Tuesday.

“Semper Fi” follows Partain and Jerome “Jerry” Ensminger, the men credited with uncovering records showing that the amount of leaked fuel that led to water contamination was many times greater than the Marine Corps acknowledged.

A congressional hearing in 2007 revealed that the camp ignored a directive from the Navy to inspect its water systems for possible contamination and to develop a protocol for the safe disposal of hazardous compounds.

The Marine Corps at Lejeune routinely dumped fluids containing harmful chemicals, which leached into groundwater and eventually contaminated a well. For decades, buried tanks also leaked fuel, allowing the chemical benzene, a known carcinogen, into the ground nearby.

But Camp Lejeune failed to study the health risks of its water after toxic compounds were discovered in the early 1980s, and did not notify Marines and their families. Up to a million people who rotated in and out of the base from the late 1950s to the late 1980s relied on the water to drink and bathe.

The Marine Corps has said it wasn’t aware of the contaminants until the mid-1980s and that contacting the 750,000 to 1 million military personnel and civilians who lived at Camp Lejeune during those decades is too large an undertaking.

The federal Agency for Toxic Substances and Disease Registry sent a survey last year to about 300,000 people who lived or worked at the Marine base before 1986. The agency expects to release the findings in early 2014.

“We care about every person who has ever lived or worked at Camp Lejeune,” Capt. Kendra Hardesty, a Marine Corps spokeswoman, said last year when the surveys were being sent out. “We are concerned about these individuals and are working hard with the scientific and medical communities to try to find them answers.”

Death of daughter

Ensminger, a square-jawed ex-Marine master sergeant, is still haunted by the death of his 9-year-old daughter, Janey, from cancer in 1985. Partain, who was born at the base in 1968, is one of more than 70 men who lived there and now suffer from rare male breast cancer.

During four years of filming that ended last year, the two men heard mention of a cemetery near Camp Lejeune where hundreds of sick and malformed babies were interred.

“I don’t think any of us believed it existed,” said Rachel Libert, an independent documentary filmmaker who co-directed “Semper Fi” with Tony Hardmon, a veteran cinematographer. Seeing it “was . . . very weird,” she said. “It was a graphic representation of the issue to see all these graves.”

As news of the film’s Oscar worthiness spread, so did interest in Congress. “Suddenly, people on Capitol Hill were requesting DVDs from us, and links to watch it online,” Libert said. “People were taking it more seriously.”

“I thought it was a very powerful presentation of the story,” said Rep. Brad Miller (D-N.C.). He said a friend who lived at the base as a child believes her reproductive problems are tied to the water there, and others have told him they ignored symptoms that turned out to be cancer, not knowing about the water.

“If it were not for a handful of Marine veterans, nobody would know about this thing. The Navy has certainly had to be pulled along very unwillingly to acknowledge that there was a problem with the water,” Miller said.

Miller and Rep. John D. Dingell (D-Mich.) reintroduced legislation last year that would provide medical assistance to hundreds of thousands of civilians and military personnel who spent time at the camp. The bill is stalled in the Veterans’ Affairs Committee under Rep. Jeff Miller (R-Fla.).

Similar Senate legislation was introduced by Richard Burr (R-N.C.), Charles E. Grassley (R-Iowa), Kay Hagan (D-N.C.) and Bill Nelson (D-Fla.). It is awaiting a vote in the upper chamber.

An agency report

Many former residents first learned of the water contamination in 1999, when questionnaires arrived in their mailboxes from the Agency for Toxic Substances and Disease Registry.

The agency focused on women such as Partain’s mother, who were pregnant while living on base between 1968 and 1985. In 2003, the agency issued a report showing 103 cases of birth defects or childhood cancers among nearly 12,600 births in the survey — up to five times the normal rate, researchers said.

For the documentary, former residents looked into the camera and said they wondered for years how they got cancer. The film introduced viewers to a healthy looking ex-Marine, Danita Watkins, in 2007 and chronicled her deterioration and death from cancer two years later.

“It was the first time I had someone not survive the making of a film,” Libert said.

Ensminger, who joined the Marines in 1970, started digging into Camp Lejeune’s documents after he saw a news report about the contamination. His ex-wife became pregnant with his daughter, Janey, during a stint at the base. She developed cancer at age 6.

“I see all these memorandums, all this stuff that was going on. I’m thinking to myself, ‘For God’s sake, I was right there,’ ” Ensminger said in a telephone interview.

“I spent a quarter century of my life in the Marine Corps,” he said. “You talk about being disillusioned. I was walking around in a daze. Many times I had to ask myself, ‘Did I throw away 25 years of my life for a lie?’ ”

Partain partnered with Ensminger in 2007. He has found 73 men who lived at the camp and experienced breast cancer, an unusually high number for such a rare illness.

“The bad news is I was conceived, carried and born at Camp Lejeune,” Partain said. “What happened to me in the womb I will carry for the rest of my life, and will more than likely be the end of my life at some point.”

When Ensminger and Partain heard tales of a graveyard section called Baby Heaven two years ago, Partain, whose parents left the camp shortly after his birth, went back.

Baby Heaven isn’t its official name. But local residents called it that, along with Baby Land, as it grew to accommodate more than 700 graves, said Carmen Miracle, the city clerk.

Partain stared at the graves of four babies born between 1967 and 1968, within months of his birth. “We could hear him crying before we found him,” Libert said.

His voiced started to crack again when he talked about the importance of the documentary last week.

“It gives the little guy a voice. Now people can hear what we have to say, not just what the Marine Corps says,” Partain said. “Lies and coverups hate sunshine. Documentaries like this are our way of bringing sunshine to uncover the truth.”