“There’s only one problem,” Torres said. “The Zimapán Dam, built in the 1990s, flooded the valley floor west of the mountain. If the cave is located on that side, it may be underwater.”
“Underwater, you say?” Madero turned to Dirk and Summer and winked. “Now, who do we know who could pull off an underwater search of that nature?”
Dirk and Summer looked at each other and grinned.
13
The tranquil expanse of open water appeared much like any other portion of the Caribbean. Only the occasional dead fish slapping against the bow of the Sargasso Sea gave hint of anything amiss. The NUMA research ship cut its engines and eased to a drift in the lightly choppy seas.
Two days had passed since they had slipped into Havana Bay under the watchful eye of a Cuban patrol craft and offloaded the Alta’s injured crew and oil workers. A Cuban Revolutionary Navy tender had pulled alongside and hoisted a diving bell over to the NUMA ship. The Canadian dive team climbed from the NUMA decompression chamber into the pressurized bell, which was transported back to the Cuban ship, where the men would complete their decompression cycle.
Captain Knight waited for the last of his men to debark, then approached Pitt at the gangway. “I hate to think of how many men we would have lost if you hadn’t responded to our distress call. I can’t thank you enough.”
“Lucky thing we were in the neighborhood.?
?? Pitt nodded at the antiquated ambulances beginning to pull away from the dock. “We would have been happy to drop you in Key West.”
Knight smiled. “We’ll be well treated. We’re operating under a contract with the Cuban government, so it’s probably better we’re here to sort through the repercussions. Hopefully, I’ll be able to smooth over the fact that we won’t be able to tap that exploratory well for a while.”
“I wish you luck,” Pitt said, shaking hands.
Moving at a measured pace, Knight stepped ashore, then turned and gave the crew of the Sargasso Sea a sharp salute.
As the gangway was secured and the mooring lines retrieved, Giordino approached Pitt with a box of Ramón Allones Cuban cigars under one arm.
“How did you score those?” Pitt asked. “Nobody was allowed off the ship.”
“I made fast friends with the harbor pilot. They cost me two bottles of Maker’s Mark.”
“I’d say you got the better end of that deal.”
Giordino grimaced. “Not if you consider they were my last drops of booze smuggled aboard ship.”
They stood at the rail, watching the historic Malecón slip by, as the Sargasso Sea made its way out of the compact harbor. Pitt had set foot in Havana years earlier and was struck by how similar the waterfront appeared, as if the march of time had somehow bypassed the city.
The NUMA ship soon found open water. Shedding its Cuban escort, it beat a quick turn around the island’s western tip, backtracking on a southeastern tack toward Jamaica. Reaching one of Yaeger and Gunn’s dead zones, the Sargasso Sea came to a halt and a flurry of activity began. A team of scientists took water samples, lowering collection devices to varying depths and rushing them to the lab.
In the meantime, Giordino prepped an autonomous underwater vehicle. The torpedo-shaped AUV was packed with sensors and a self-contained sonar system. With a prearranged road map, the device would dive to the bottom and skim along the seafloor in a set grid pattern, mapping the contours.
Pitt watched as Giordino released the AUV from the stern A-frame. “When will she be back?”
“About four hours. She’s on a short leash for the initial run, surveying less than a square mile. No sense in running her crazy until we can determine the source of the dead zone.”
“My very next intent.” Pitt migrated to the bridge, where he had the captain hopscotch the vessel around the area, stopping at half-mile increments for additional water samples. When it was time to retrieve the AUV, Pitt grabbed Giordino and ducked into one of the labs. A dark-eyed woman in a blue lab coat motioned for them to join her in front of a computer monitor.
“Do you have some results for us, Kamala?” Pitt asked.
Kamala Bhatt, the Sargasso Sea’s marine biologist, nodded. “We do indeed.”
She took a seat on a stool. “As you know, dead zones are common all over the world’s oceans. They are typically found near the mouth of rivers carrying polluted runoff. But this site, and the others identified by Hiram Yaeger, are far from land. Our initial testing does show a decrease of oxygen levels, but it is less than we would otherwise expect.”
Pitt shook his head. “So there is in fact no dead zone here?”
“On the contrary, the toxicity levels are quite high. It just wasn’t the animal I expected to find.” She pointed to the computer screen, where a bar graph displayed the composition of one of the water samples. “The water tests lower for oxygen content than typically found, but there seems to be another factor that is increasing the impact to aquatic life. I had to delve deeper until I found one element out of place. Its concentration is off the charts.”
“What’s that?” Giordino asked.
“Mercury. Or methyl mercury, to be precise.”