“I’m showing a pH of 8.1,” she said after testing the first sample. “The acidity is just a hair above the levels in the surrounding waters but not significant.”

She proceeded to test all of her water samples and then the vials collected by Trevor. The results were nearly uniform for each vial tested. As she checked the results of the last sample, a defeated look crossed her face.

“Again, the pH level is reading about 8.1. Remarkably, the water around the Terra Green facility shows no abnormal levels of acidity.”

“That seems to blow our theory that the plant is dumping carbon dioxide,” Trevor said.

“A gold star for Mitchell Goyette,” Dirk said sarcastically.

“I can’t help but wonder about the tanker ship,” Summer said.

Trevor gave her a quizzical look.

“We got sidetracked and couldn’t prove it, but Dirk and I both thought the tanker might be taking on CO2 rather than unloading it.”

“Doesn’t make much sense, unless they are transporting it to another sequestration facility. Or are dumping it at sea.”

“Before trailing a tanker halfway around the world, I think we need to take another look at the site where we measured the extreme water acidity,” Summer said, “and that’s Hecate Strait. We’ve got the gear to investigate,” she added, motioning toward the NUMA boat.

“Right,” Dirk agreed. “We need to look at the seabed off Gil Island. The answer has to lie there.”

“Can you stay and conduct a survey?” Trevor asked with a hopeful tone.

Dirk looked at Summer. “I received a call from the Seattle office. They need the boat back by the end of the week for some work in Puget Sound. We can stay two more days, then we’ll have to hit the road.”

“That will allow us time to examine a good chunk of territory off Gil Island,” Summer said. “Let’s plan for an early start tomorrow. Will you be able to join us, Trevor?” It was her turn to give a hopeful look.

“I wouldn’t miss it,” he replied happily.

As they were leaving the dock together, the brown Jeep with a rental-agency sticker on its bumper cruised slowly along the adjacent roadway. The driver stopped briefly at a clearing, which gave an unobstructed view of the municipal dock and harbor. Behind the wheel, Clay Zak gazed out the windshield, studying the two boats at the end of the dock tied up one behind the other. He nodded to himself, then continued driving slowly down the road.

Chapter 36

36

WHEN TREVOR ARRIVED AT THE DOCK AROUND seven the next morning, Dirk and Summer were already laying out their sonar equipment on the stern deck. He gave Summer a quick peck while Dirk was occupied coiling a tow cable, then he pulled a small cooler onto the boat.

“Hope everyone can stomach some fresh smoked salmon for lunch,” he said.