Michelle Greene and Lindsay Dragich aren’t sure what they are going to do now.

The two physical education majors stopped by the California State University, Dominguez Hills bookstore Monday only to be stopped by yellow caution tape.

A Saturday morning fire probably caused by faulty wiring closed the entire student union complex and likely ruined textbooks in the bookstore, where the fire was contained.

It is unclear how much if any of the contents — mainly books and clothes worth about $1.3 million — can be saved.

“I just saw it in the paper and the whole bookstore was in flames,” said Dragich of San Pedro. “We haven’t gotten most of our books. Some weren’t available, others weren’t in stock. And we wait to see if we need them because they are so expensive. Now they are burned.”

But the two 22-year-olds are in the minority. Classes started Aug. 28 so most students at the Carson campus had already nearly emptied the store of books.

“If this happened a week or two ago the damages would have been tripled,” bookstore manager Derek Dioses said.

As it happens, the bookstore’s main role for the rest of the semester was to sell blue books for exams, pencils and snacks, Dioses said.

Still dozens, or perhaps hundreds, of students could be without books for a while. It was impossible to know how many texts were on back order or special order because Dioses couldn’t retrieve the information from his computer.

University officials recommended that students who still need books look online at sites such as amazon.com and barnesandnoble.com, or try the bookstores at California State University, Long Beach or Loyola Marymount University in Westchester.

The state fire marshal spent most of Monday investigating the cause of the fire and the safety of the building.

But the county Fire Department and sheriff’s arson investigators ruled out arson and blamed the blaze on faulty wiring.

“There are no signs it was an incendiary fire,” sheriff’s arson investigator Ed Nordskog said. “We have a video and there’s nothing on the video that makes us suspicious. There are no witnesses. There was no break-in.”

Dioses will begin moving the bookstore’s contents to the old administration and records building a few hundred feet away. As workers inventory the books, they’ll also begin salvaging the bookshelves and other furniture.

“We don’t even have a game plan yet,” Dioses said.

From the outside, nothing seemed damaged at the student union. Still the Loker Student Union — including the half-dozen restaurants on the bottom floor — was closed Monday. Before the eateries, meeting rooms and student government offices can reopen, the air conditioning and gas systems must be cleaned and cleared for operation.

Kim Clark, director of the student union, was hopeful that the complex would reopen by Wednesday.

Until then, catering trucks will provide lunches and snacks.

The fire broke out near the bookstore’s cash register just before 8 a.m. Saturday. Though county firefighters stationed across the street arrived within 60 seconds, the fire caused an estimated $2 million in damage, according to university officials.

The blaze fed off clothing and greeting cards and the firefighters contained it to that area within 20 minutes, officials said.

Jimmy Chacon, 18, will miss eating lunch at the Bistro.

But he’s more concerned about his special order of Economy of Social Issues.

“Now,” he said, “I’ll have to keep photocopying pages from other students and teachers.”