Sellitto said, “Better keep going on this one, Linc. Fill in the gaps. I see a lot of ’em.”
Rhyme was staring at the ceiling. His face knotted. “We…I should’ve thought better. Why would Forty-Seven go to the trouble to get a hard hat and go into the jobsite to buy a weapon from somebody? They’d meet in a bar or on the street somewhere. No, he needed access to the site itself.”
“Why?” the detective asked.
Rhyme looked at Sachs, who said, “I was just down to the site again. I found traces of RDX near several of the shafts.”
The main ingredient in C4 plastic explosive.
“At a construction site?” Sellitto asked. “C4’s never used commercially.”
It was a military explosive.
“And the site manager told me that one of his workers has gone missing. It was right after Unsub Forty-Seven was in the site. And there was a half ton of grout missing from the pallets in Area Seven.”
“Grout?” Cooper asked.
Rhyme explained, “It’s Forty-Seven’s plan. It’s why he’s here: planting gas line bombs and C4 charges to mimic earthquakes. Last week he placed the gas line IEDs in buildings near the geothermal site. Then he goes to the site, in his hard hat and vest, and meets the now-missing worker, who takes him to Area Seven. He drops C4 charges down some or all of the shafts, and the worker pours grout down them so that when the charges blow, you won’t hear the explosion. Then Forty-Seven ditches the empty shoulder bag and leaves—where we see him on the subway. Later that night, I’m guessing, he kills the worker and disposes of the body.”
“Pretty fucking bizarre, Linc. But can that even happen, explosions causing earthquakes?”
“That’s why I asked our expert here.” He looked at Edward Ackroyd. “You know if there’ve ever been any insurance claims because explosions in mines caused earthquakes?”
The Englishman reminded them of his earlier thoughts, about fracking and geothermal drilling potentially leading to quakes. “But as for explosions? I’ve never heard of that. But I’ll ask my research associate again. Somebody here or in London could have a look, I’m sure.”
“Do that, if you would.”
Ackroyd stepped to the corner and pulled out his phone. After a brief conversation he returned. “Sorry to report, our head researcher’s never heard of an earthquake induced through explosions. She’ll ask at headquarters in London and our other offices when they’re open. My initial thought is that it’s rather unlikely.”
Rhyme noticed Sachs open her purse. She withdrew a business card, read a number and placed a call.
Waiting for the connection, she said to the room, “Don McEllis, the state mining inspector.”
A voice answered, “Hello, Amelia. How are you feeling?”
“Fine,” she said shortly. “Listen, you’re on speaker here with Lincoln Rhyme, an NYPD consultant, and a few other people.”
“Oh. Sure.”
“Dan, this is Lincoln.”
“Don,” Sachs corrected.
“We need to know if somebody can induce an earthquake by explosion.”
There was a pause. “You think these quakes in the past few days aren’t naturally occurring?”
“We aren’t sure. Can explosives cause an earthquake?”
“Well, in theory, yes, but you’d need a nuclear device, in just the right place, just the right megatons. But short of that, no.”
“C4 couldn’t do it? Do you know C4?”
“Plastic explosives, sure. But, no, it’d be impossible. Even a ton or two placed right on a fault line. That’s not how quakes work. But…”
Silence.
“Hello?” Rhyme asked.
They heard fast keyboarding. “Okay, okay. Give me an email address. I want you to see this.”
Cooper did so and a moment later a tone announced the arrival of a message.
McEllis said, “I’ve sent two seismograms.”
Cooper’s astute fingers typed on the keyboard, and the charts—with the familiar waves anyone with a TV and a love of natural disaster blockbusters would recognize—appeared on the screen. “Got them.”
The inspector continued, “The top one is from the most recent tremor here.”
At the far left, the stylus’s black line rose and fell only a little as it moved to the right over the course of several minutes. Then halfway along the chart the line jumped up and down in series of broad, sharp waves. As time passed, they tapered and grew smaller and smaller until the line returned to what it had been before the tremor.
“Now look at the second chart. It’s a record of a real earthquake, one in California. It seems similar but there’s one subtle difference. In the real quake, we can see just a bit of pre-quake ground motion a few seconds before the main disturbance. There’s none of that in the tremors here.”
Rhyme said, “So the explosions weren’t inducing an earthquake; they were mimicking one.”
“Exactly.” A moment later McEllis said, “But then how do you explain the fires…Ah, wait: Unless they were caused by charges too—separate ones, to make it more credible that it was a quake.”
When no one answered, he asked in an uncertain voice, “What exactly is this all about, Amelia?”
“We’re not sure yet, Don. But if you could—please keep it to yourself.”
“Of course. Sure.”
She looked at Rhyme, meaning: Anything else?
He shook his head. She thanked McEllis and they disconnected the call.
Rhyme echoed, “And what is this all about? What’s our unsub up to?”
“Terrorism,” Sachs suggested, then shook her head. “But nobody’s come forward. And why make an attack look like a natural disaster? That’s not the terrorist profile.”
Sellitto said, “One idea: He staged the quakes to cover up the arson. Maybe he’s working for a landlord wants to torch his buildings for insurance.”
Ackroyd said, “With respect, Lieutenant, it’d be the most elaborate insurance scam in history. And, besides, professional arsonists never risk murder or assault charges. They only torch buildings when they’re empty.”
“Granted.”
Rhyme said, “Well, there’s another way to look at it. What McEllis suggested: The fires were cosmetic. Just to give more credibility to the quakes—so that nobody would look too closely at suspicious seismograms. He wants them to seem real…How’s this: He wants to stop the geothermal operation.”
Sellitto offered, “Who’s on that list? Energy industry companies would see geothermal as a threat. Somebody wants the drilling site land. It’s prime real estate.”
“Environmentalists,” Cooper suggested. “That One Earth crowd? Though I don’t think tree huggers use C4 very much…or burn down buildings with people inside.”
Sachs said, “Whatever he’s up to, Forty-Seven seems like a triggerman or mercenary to me. Access to the arms market for the C4 and gas devices. Knows weapons. Doesn’t hesitate to kill. Somebody hired him, I’ll bet.”
Rhyme was inclined to agree. He then said, “One thing: We’ve got a decision to make.”
Sachs was nodding. “To tell or not to tell.”
“Announce the fact they’re fake?” Cooper asked.
“Right. He could have a dozen more IEDs planted in the shafts.”
Sellitto said, “There’ll be some panic. Everybody’ll think terrorism.”
“So, they think terrorism,” Rhyme countered. “I think we have to. And tell people in the general area of the drilling site that there might be a bomb on their gas lines. They should look for them. And announce that if there’s another tremor, they should evacuate or check for gas immediately.”
“It’ll be the commissioner’s and City Hall’s call, but if we do announce, we tip our hand,” Sellitto said. “The perp might book on out of town. Evidence’ll disappear.”
As for the last concern, Rhyme was amused: It was very difficult to make evidence disappear from him.
“If I may make an observation?” Ackroyd said.
“Yeah, sure,” Sellitto offered.