“Now that the Dominican Republic has essentially eliminated drug trafficking by air, we are seeing an increase in narcotics activities in Dominican ports,” Daniel L. Foote, U.S. Embassy deputy chief of mission, said in a meeting with the Dominican Shipping Association. “We are in the process of talking with Dominican officials about the possibility of helping to arrange for a greater [US] presence.”

Among the possibilities is training more drug-sniffing dogs for the ports, he said.

While important, the X-ray machines do not appear to be as integral to controlling drug trafficking as Melgen’s supporters have suggested.

Melgen’s cousin, the lawyer Vinicio “Vinicito” Castillo, called it a matter “of national security, for the United States and our country” in a press conference last week. “Five million containers pass through the ports and less than 5 percent are X-rayed,” he said. “And the only machine … is only capable of scanning empty [shipping] containers.”

But port officials said fewer than 1.5 million containers pass through the ports each year. And that machine — donated in 2006 by the U.S. government — “only scans full containers,” Johansen said. Empty containers are inspected by other means.

Using the machine, Dominican ports already screened roughly the same percentage of containers as other ports in the region.

Inside a squat administration building just outside the entrance of Multimodal Caucedo, Dominican military and U.S. customs agents monitor intelligence and incoming shipping manifests looking for red flags.

If a container is flagged, the shipment is sent to the X-ray machine, a simple rectangular blue metal structure attached to a small trailer.

As a container passes through, a picture of its contents is relayed to monitors . A security officer then compares the pictures to the shipping manifest. If the image and manifest don’t match, the container is opened and manually inspected, security officials said.

Currently, there is no charge when a container is scanned, Johansen said.

Under its contract, ICSSI could charge nearly $100 per container. Estimates have put the 20-year value of the contract at between $500 million and $1 billion. Dominican officials have balked at the cost of the contract and the fact that it gives ICSSI a monopoly. Calls to phone numbers listed for ICSSI’s Santo Domingo office were not returned.

The exclusive contract appears to have already harmed Dominican ports. The U.S. was prepared to donate an X-ray machine to the port of Haina, the country’s second busiest, a business official told The Herald.

That claim was verified in an investigative report by Dominican magazine La Lupa Sin Trabas. A U.S. State Department official declined to comment because the Senate Ethics Committee is investigating the case.

The port deal and Menendez’s involvement surfaced after The Daily Caller, a conservative news website, published allegations that Menendez, Melgen and Castillo had hired prostitutes for parties at Melgen’s Dominican vacation home. The District Attorney of Santo Domingo has opened an investigation to find the source of the allegations.