NORTHPORT, Long Island (WABC) -- 7 On Your Side Investigates examined ongoing efforts by the Northport-East Northport Union Free School District to remove health risks to students at Northport Middle School following the discovery of hazardous chemicals stored below classrooms in 2017 and concerns from parents that their children had been exposed to mold and carbon monoxide among other pollutants at the school.Doctors wrote letters recommending students "be removed" from the "middle school due to chronic exposure to organic compounds, including carbon monoxide."The latest doctor's letter obtained by Eyewitness News was written in July.One parent also penned an Op Ed in the July 12 edition of The Observer claiming, "Mold sickened our child at Northport Middle School."The latest discovery of hazardous chemicals in a warehouse below classrooms, as well as cancer-causing TCE, detected at the school above state health guidelines, followed earlier scares in 2011 when students and staff reported odd, sickening smells; and the early 2000s when the Suffolk County Health Department found the school had illegally dumped toxic chemicals into the school septic system."I found all these articles from 2000. If I covered up the dates, I could have convinced people those articles were just written now because what I was reading was the very same things we were reading now," said Denise Schwartz, a concerned parent. "I don't want to in eight, 10 or 12 years start hearing about this again and start reading the same articles."Superintendent Robert Banzer, who came to the district in 2015, described the 2017 incident as, "not our best moment by any stretch of the imagination," during an August 2017 community meeting.Banzer promised to make systematic changes and said, "I have done some research into some model programs and the EPA has a 'Schools for Tools' program which really is very proactive," referring to the federal Tools for Schools program intended to help schools improve indoor air quality.Banzer said the program would be implemented district-wide.However, 7 On Your Side Investigates found according to state-required 5-year building condition surveys, available on the district website , the school district had already claimed to be using 'Tools for Schools', the very program Banzer was suggesting the district implement to resolve the pollution concerns, since 2010.Months later, Banzer admitted 'Tools for Schools' wasn't a new idea."It's been pointed out to me that the 'Tools for Schools' program has been listed on our 5-year building condition surveys in the past," Banzer said.Banzer declined repeated requests by Eyewitness News for an on-camera interview and also declined requests to speak directly to Eyewitness News by phone.In a statement, he addressed the confusion about the 'Tools for Schools' program."The Tools for Schools Program was listed on the 2010 and 2015 Building Conditions Surveys. When I came to the district in 2015, I saw the need to decentralize the response and ensure more involvement and consistency from the building level teams which includes administrators, teachers, and nurses, in addition to the custodial/maintenance staff. The training that took place during the 2017-2018 school year involved these stakeholders and enabled us to accomplish this goal."As part of the program, Banzer shared with the community blank, sample air quality-related checklists and other data sheets around the use of chemicals and the maintenance of buildings which would be used as part of the program.District policies also required lists of all hazardous chemicals in the district and the individuals who handle them or come in contact with them.7 On Your Side Investigates requested copies of those documents and while Banzer has told Eyewitness News they exist, they have not been provided.Parents have also worried that buses in the district bus depot beside the school could be idling and emitting pollution after some of their children tested positive for elevated levels of carbon monoxide in their blood."There comes a point where you have to do what you can do to fight for your own family," said Tara Mackey, a concerned parent. "I can't be quiet."Banzer reassured parents in a school board meeting that the district was working hard to enforce its "no idling policy.""We monitor that a couple different ways," Banzer said. "That can be done through GPS and how long the bus is sitting and at that point the director can talk to the driver if necessary. Again, we have an anti-idling policy in the district. That is something we are working very hard to make sure that it is being followed."However, when 7 On Your Side Investigates requested bus GPS data the district responded, "The District does not have in its possession any documents responsive to your request."After several phone calls and emails, Banzer said the district did have GPS data but it hadn't been able to compile it for Eyewitness News.7 On Your Side Investigates is waiting for those records.Parents with concerns remain frustrated."We're trusting the school, the district and every adult in the school to be keeping our kids safe in every way. So we would assume that this problem would never have existed," Schwartz said.Jim Hoffer, Danielle Leigh and the 7 On Your Side Investigates team at Eyewitness News want to hear from you! Call our confidential tip line 1-877-TIP-NEWS (847-6397) or fill out the form BELOW. You can also contact Jim and Danielle directly:Email your questions, issues, or story ideas toFacebook: facebook.com/jimhoffer.wabc Twitter: @NYCinvestigates Email your questions, issues, or story ideas toFacebook: DanielleLeighJournalist Twttier: @DanielleNLeigh