Poisoned Ground: The Aftermath of NMH’s Legacy Of Pesticides

By Alexandra Tse

Gray dots on a site map highlight the former apple orchard at Northfield Mount Hermon, all areas where soil is still contaminated with lead and arsenic from pesticides sprayed over 100 years ago. This map is part of an Orchard Management Plan submitted in 2005 by ECS, an environmental consulting company. 

NMH abandoned the Mount Hermon apple orchard that same year. Since then, it has been overwhelmed by invasive bittersweet vines, poison ivy, and trash. The orchard was cleared last summer because “it had gotten to a point where it was not saveable,” said Jeff Seymour, the director of facilities and grounds. But it wasn’t always like this. The orchard was once productive, said Mary Hefner, a biology teacher at NMH. “We used to have a team tradition in my cross country team, and every Friday, we would run to the apple orchard and pick an apple.”

According to a reference in the 1903-1904 Principal’s Report, The Mount Hermon orchard was laid out in the fall of 1904 and completed in the spring of 1905. Students in the work job program, faculty, and workers scaled wooden ladders to pick apples, pressed cider, and pruned and mowed the orchard. They picked roughly 100,000 apples annually and pressed approximately 2,000 gallons of cider for drinking in the dining hall. However, the pesticides sprayed on the orchard that contained lead and arsenic persisted much longer than the apples. 

Over the decades, while the site looked harmless, students and faculty alike were unaware of the mayhem under the surface. “The soil was certainly heavily contaminated because they were spraying apples with all kinds of terrible chemicals,” said Peter Weis, the school archivist. Mount Hermon School sprayed Lead arsenate (LA) pesticides on the site for decades because of their low toxicity to plants and effectiveness in controlling insects – particularly the codling moth. 

LA pesticides were not only a prominent problem for NMH; at one point, it was the most popular pesticide in the nation. According to the Washington State Department of Ecology, The USDA recommended it broadly, and millions of acres were sprayed nationwide to protect crops. As farmers increased the frequency of application, concerns over its use increased. 

The potential danger posed to human health by lead and arsenic contamination in historic orchards is complex and fraught with scientific uncertainties and competing interests. Arsenic is a known human carcinogen. Exposure to lead, especially prenatally and in childhood, can lead to neurological damage. These pesticides were generally phased out by the 1960s; however, according to the Orchard Management Plan, there is no information regarding exactly when Mount Hermon stopped using them. 

Even though it has been at least 77 years since LA was last used at NMH, it was designed to be persistent; it is that same persistence that is now causing environmental contamination issues many years after its use has ended. As elements, lead and arsenic do not break down, they are buried deeper and deeper into the soil over time. They stay in the soil and stay toxic for decades. 

Peter Sniffen, the Sustainability Program Coordinator and an Environmental Science teacher, learned about the contaminated soil in the orchard from a board of trustees member last spring and looked for ways his Advanced Environmental Science class could get involved. Cynthia Zhang ‘23, one of the students in his class, created an Orchard reclamation research proposal, which included an ecological monitoring plan on how NMH should handle the contaminated soil as well as necessary research, observations, and testing that could help the school make sound environmental decisions for the future of the orchard’s land. 

According to soil sample testing in the Orchard Management Plan, the average arsenic detected in the orchard soils exceeded the naturally occurring or “background” ranges for Massachusetts. This raises the vital question of how many students, faculty, and workers throughout the orchard’s operation were exposed to the hazardous lead arsenate during and even after its use in the orchard. There is no doubt that excessive exposure to either substance can adversely impact health, but in this case, any risks are almost exclusively long-term. “I wonder if these toxins caused any health problems for people later on,” Zhang said. “I don’t understand why they would keep an orchard at such close proximity to students who literally have class around the area and move around the place every day.”

The orchard was abandoned in 2005 when NMH ran into problems around health and safety regulations. The school had to start informing anyone within 100 yards of the orchard 24 hours before spraying pesticides. “The problem is that the orchard was within 100 yards of students under the age of 18 because of Overtoun being right there. So all of the parents [would] have to be notified and respond that they understood and okayed it within 24 hours of spraying,” Weis explained. “If one person or one family objected then you would have a problem. You would have to have every single person sign off. And that was just not going to happen.”

Richard Odman, who managed the orchard from 1977-2005, claimed that the pesticides used under his direction contained neither lead nor arsenic. But even so, “it was a bigger problem PR wise,” Hefner said. 

Over the years, the school neglected the orchard, and it became a place where students could hide out and break school rules, a dumping ground littered with beer bottles and cigarettes. “It was more of just an eyesore than anything else,” Seymour explained. For 18 years, the orchard remained untouched and forgotten. Until recently, many people at NMH were unaware of its existence. “I was very surprised when I found out there was an apple orchard because no one really talked about it,” said Zhang. “I walked past it a bunch of times, but I didn’t know it was like an apple orchard because there were just a bunch of dead trees.”