School police narrowing down leads on who brought mercury to Johnson Junior High
September 14, 2016 - 5:44 pm

Students arrive at Johnson Junior High School Tuesday, Sept. 13, 2016, in Las Vegas. The school reopened after being closed for a mercury contamination cleaning since Thursday. (David Becker/Las Vegas Review-Journal) Follow @davidjaybecker

Johnson Junior High School students Ni'Airra Jackson, 11, left, and Ny'Rrah Jackson, right, listen as Brooklynn Silas, 11, speaks about the mercury scare during an interview outside their closed school on Monday, Sept. 12, 2016, in Las Vegas. (Bizuayehu Tesfaye/Las Vegas Review-Journal) Follow @bizutesfaye

A sign is seen posted at Johnson Junior High School Tuesday, Sept. 13, 2016, in Las Vegas. The school reopened after being closed for a mercury contamination cleaning since last Thursday. (David Becker/Las Vegas Review-Journal) Follow @davidjaybecker

Students arrive at Johnson Junior High School Tuesday, Sept. 13, 2016, in Las Vegas. The school reopened after being closed for a mercury contamination cleaning since Thursday. (David Becker/Las Vegas Review-Journal) Follow @davidjaybecker

Michael Barton, chief student achievement officer with the Clark County School District speaks during a news conference at Walter Johnson Junior High School Tuesday, Sept. 13, 2016, in Las Vegas. The school reopened after being closed for a mercury contamination cleaning since Thursday. (David Becker/Las Vegas Review-Journal) Follow @davidjaybecker

Ching Vogl, right, and her daughter, Fiona Vogl, leave Johnson Junior High School Monday, Sept. 12, 2016, in Las Vegas. The two left empty-handed after discovering that Fiona's backpack, lunchbox and purse were destroyed because of mercury contamination. (David Becker/Las Vegas Review-Journal) Follow @davidjaybecker

Randy Nattis, federal on-site coordinator for the EPA, demonstrates how students' belongs are tested for mercury contamination during at news conference at Johnson Junior High School in Las Vegas on Friday, Sept. 9, 2016. Mercury was found at the school this week. (Bizuayehu Tesfaye/Las Vegas Review-Journal) Follow @bizutesfaye

Clark County School District superintendent Pat Skorkowsky talks to members of the news media Friday, Sept. 9, 2016, at Johnson Junior High School in Las Vegas regarding mercury found at the school this week. (Bizuayehu Tesfaye/Las Vegas Review-Journal) Follow @bizutesfaye

Consuela Nicole demands answers from an Environmental Protection Agency official during a town hall meeting at Jacobson Elementary School on Thursday, Sept. 8, 2016, in Las Vegas. The Clark County School District held the town hall to discuss the recent mercury contamination at Johnson Junior High School. (Benjamin Hager/Las Vegas Review-Journal)

Denise Allen, middle, with Monica, Juliana and Ernesto Brown, listens to a briefing during a town hall meeting at Jacobson Elementary School on Thursday, Sept. 8, 2016, in Las Vegas. The Clark County School District held the town hall to discuss the recent mercury contamination at Johnson Junior High School. (Benjamin Hager/Las Vegas Review-Journal)

A worker cleans up trash left by parents at Walter D. Johnson Junior High School in Las Vegas on Thursday, Sept. 8, 2016. The school was closed on Wednesday after a student brought mercury to the school. (Brett Le Blanc/Las Vegas Review-Journal) Follow @bleblancphoto
School district police are narrowing down “a couple of key leads” about who originally brought at least a quarter-cup of mercury to Johnson Junior High School this month, Capt. Ken Young said Wednesday.
Young said officials hope to identify the person or people responsible and put the investigation “to rest” by the end of the week.
Police still believe a student brought the toxic, metallic substance to the school, which led to a lockdown Sept. 6 and the school’s closure and decontamination until Tuesday.
The contamination was most concentrated in the school’s gymnasium and locker rooms, where Environmental Protection Agency officials found mercury vapor levels at least 10 to 15 times higher than a federally determined safety limit.
As a result, crews Monday removed a 30 foot-by-30 foot portion of the gym floor and two 10 foot-by-20 foot carpeted areas at the gym’s main entrances during the decontamination process.
The school’s contamination led EPA officials to screen about 80 student and staff homes for mercury this week.
Those screenings revealed mercury contamination at just one home. The two adults and two children living there were temporarily relocated as officials decontaminated the house.
Margot Perez-Sullivan, an EPA spokeswoman, said carpeting was removed from the contaminated home’s student bedroom and other contaminated objects were thrown away.
“We saved what we could, and the things that were too hot to be salvaged, we had to dispose of,” Perez-Sullivan said, adding that the EPA had completed the home’s decontamination, allowed the family to return and handed the investigation over to the school district.
Though mercury was found in only one home, Young said Wednesday there was “no indication at this time” that the student who lives at the contaminated home was the one who brought the substance to school.
As of Wednesday, it was unclear whether the person or people responsible for bringing the mercury to school would face criminal charges.
Las Vegas Review-Journal reporter Neal Morton contributed to this report. Contact Rachel Crosby at rcrosby@reviewjournal.com or 702-387-5290. Find @rachelacrosby on Twitter.