Sebastian Velez, an assistant resident dean at Harvard’s Kirkland House, is a graduate student in biology who studies arachnids. But after a massive earthquake struck Haiti, he put spiders aside, and plunged in to help with relief efforts.

Velez had been on his way to the Dominican Republic to assist on a water purification project near Pedernales in the southwest corner of the country, on the Haitian border. The project was sponsored by Children of the Border, a nongovernmental organization that Velez founded five years ago to help Haitian refugees who live in uneasy alliance with their Dominican neighbors.

He arrived in the Dominican Republic two days after the quake, and quickly teamed up with five Cambridge-area undergraduates, four of them from Harvard, who were already working on the water project.

Harvard officials strongly discourage students from heading to Haiti in an effort to help. Trained medical personnel are the first priority there. But these students were already near the massive disaster. So they asked themselves: How can we help?

They set their sights on Jacmel, a small Haitian coastal city nine hours from Pedernales by sea.

For one thing, Jacmel had not yet received aid, even though it was half-destroyed by the same temblor that leveled Port-au-Prince, the capital. Velez received his first accounts of damage there from Haitian fishermen docking their small boats near Pedernales.

For another thing, Jacmel is home to the Faith & Love in Action orphanages, owned by Marlaine and Daniel Alix, the parents of Harvard undergraduate Ruth Vanessa Alix ’10, who has been in touch with Velez and the others.

A native of Haiti, she lived there for her first 12 years. She visits Jacmel every summer and on spring break. Her parents founded the Faith & Love in Action Foundation in 1996 and Aid International there in 2000. The groups run orphanages, schools, and churches throughout Haiti, and coordinate medical aid.

By Monday (Jan. 18), the ad-hoc Harvard relief team and volunteer Dominican civil defense workers had loaded $23,000 worth of food, water, medicine, and tools aboard a Dominican navy gunboat, which Velez had convinced the government to dispatch. The relief team had bought, inventoried, packed, labeled, and loaded the relief supplies.

Jacmel needed those supplies fast, said Velez, a man in a hurry who gave his last cell phone interview from a motorcycle. “That’s the point of all this,” he said.

The funds were wired to Velez from the American Humanist Association, a Washington, D.C., aid group dedicated to the idea of being, as they advertise, “good without God.”

A second sum of $20,000 arrived earlier this week, and Velez spent it on truckloads of medical supplies for another trip to Jacmel scheduled for Friday (Jan. 22). Reports from the town said amputations were being conducted without anesthesia, and medical supplies were critically needed.

“We went to the pharmacy and raided the medicines,” said the jovial Velez, who paid for the goods out of a knapsack stuffed with Dominican pesos. He said he was careful to leave one of everything on the store shelves for local use.

For the initial trip, it took 12 hours of hard work — until 3 a.m. Sunday (Jan. 17) — to inventory and load all of the supplies, including pallets of bottled water, thousands of pounds of rice and sugar, containers of powdered milk, boxes of sardines, bags of dried pasta, jugs of cooking oil, wheelbarrows, and cooking utensils. The cargo also included hand tools for breaking through collapsed structures, including sledgehammers, pry bars, pickaxes, hammers, and crowbars.

Local farmers donated bananas and plantains. A hardware store provided a truckload of bottled water. Other donors provided hundreds of tents. A few Dominican doctors signed on for the trip.

Mindful of potential dangers, Velez was the only student to accompany the Dominican gunboat and its crew on the journey.

Velez e-mailed photos of the relief operation. One showed him atop a stack of large white sacks that were stenciled in blue with the word “Humanists.” Another showed Matthew C. Mulroy ’12, tall and smiling, hefting a 100-pound sack of flour.

“I feel lucky we’ve gotten to be part of this,” said Tracy T. Han ’11, a Currier House resident with a special concentration in global health. “I’m so glad we’ve been able to help in the little way we can.” The other undergraduates helping in the Dominican Republic were Fabian A. Poliak ’11, Annemarie E. Ryu ’13, and Massachusetts Institute of Technology senior Yvette M. Beben.

All were safe and well, Velez said, staying in a Pedernales hotel, and would not enter Haiti. The students are scheduled to fly back to Boston Saturday.

When the gunboat arrived in Jacmel, Velez said, it was greeted by 300 Haitians eager to help unload the supplies. Since it was the town’s first glimpse of outside aid, the work went by “in a flash.” The Haitians set up a bucket brigade to unload the vessel. They then used wheelbarrows to transport the goods to waiting trucks.

Velez ventured into the small city. Though not as hard-hit as Port-au-Prince, he still saw some now-familiar sights: streets blocked by fallen rubble, buildings collapsed into pancaked stacks, crushed cars, and crowds of dazed pedestrians. The residents, worried by frequent aftershocks, were sleeping outside at night.

Velez checked that the food was stored safely and then headed for the Faith & Love orphanage in a little white truck – a Haitian “tap-tap” – that was jammed with food and water.

Alix, the Harvard undergraduate whose parents own the Faith & Love orphanages, said by e-mail that all 85 children in the Jacmel facility survived the quake and were in good health. But her parents run two other orphanages in Carrefour, where the epicenter of the earthquake was. There was no word yet on the fate of the children there, she said.

While in Jacmel, Velez talked with Haitian doctors, who gave him a five-page list of needed medical supplies. There was adequate food on hand, but distribution was not yet running smoothly.

Returning to Pedernales, he bought the requested medical supplies – 4 tons worth – and on Thursday (Jan. 21) was loading the gunboat a second time with the aid of the undergraduates.

He said that some of the Dominican volunteers have been working for 24 hours without food and that he himself had just gotten his first four hours of sleep in days.

“It’s catching up to me,” he wrote in an e-mail Thursday afternoon – adding that sleep would come on the next boat ride to Jacmel. Velez plans to leave the Dominican Republic and be back in Cambridge in time to teach a class on Monday — back to his spiders.

But on Thursday, the second relief shipment still wasn’t ready. He revved up his motorcycle and shouted into the cell phone: “Gotta go!”

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