An independent review has found no link between a school campus and health problems among pupils and staff.
Significant concerns were raised about Buchanan and St Ambrose high schools in Coatbridge, North Lanarkshire, which were built on a former landfill site, after reports of blue water coming from taps.
Four current and former staff were diagnosed with cancer, while parents kept some pupils away from classes.
The Scottish Government-ordered review into the problem has now said the schools are safe and will reopen as planned next week.
However, North Lanarkshire Council was criticised for failing to engage properly with those who raised concerns.
Teaching union NASUWT said its members intended to strike on Monday, but would review their position after the report is studied by their advisors.
Public health consultant Dr Margaret Hannah, who co-led the review, said: "Many people were concerned about possible health risks from the previous use of the campus site.
"We listened carefully to the concerns of parents and teachers and worked with various experts in their field to determine the areas to test within the campus.
"Our principal finding is that the schools are safe, the site is safe and there is no link between the school and the reported health issues.
"However, we have made recommendations for some work to be carried out in order to provide further public reassurance.
"One of our recommendations includes convening a site recovery group to provide an open channel to share information and allow any concerns to be raised regarding the well-being of those on the campus.
"Working together is key to restoring public confidence and we hope our findings will help all the communities in Coatbridge and beyond work towards common goals and in the best interests of the pupils and staff."
Over the summer holidays, mother Pauline McMullan has been unsure whether her son Aidan should return to St Ambrose next week - but has now decided that he should although she still has concerns.
She told STV News: "It looks as if they're saying that it's safe in the report and I want Aidan to go back but it also says in the report some work's needing done and that has to be done before the school opens.
"I wouldn't say I'm 100 per cent convinced everything's okay. It's a fabulous school but we need more information from the council, we need them to be on this and we need our children back in a safe environment - but we're not 100 per cent convinced it's a safe environment yet."
St Ambrose has around 1200 pupils and shares the site with Buchanan which serves around 100 children with additional support needs. The campus opened in 2012.
Water samples taken during the review passed all quality standards.
The report also found the school's methane membrane under the building was installed correctly and no landfill-related gases were detected.
Around 50 soil samples were taken during the investigation where no concerns were raised.
However, the report said the council should remove one chemical - described as "not of concern" - found on the site as soon as possible.
Deputy First Minister John Swinney said: "I am grateful to the review team for their work over the last two months. This has been a complex and challenging set of circumstances to review in such a short timescale.
"The report provides reassurance to parents, pupils and staff of the school that there are no links between ill-health and the campus.
"The review also finds, however, that North Lanarkshire Council and NHS Lanarkshire did not handle this issue at all well. They did not engage with parents sufficiently early or in an inclusive manner.
"The recommendations will ensure statutory bodies engage far more proactively with parents, staff and pupils to rebuild the trust and learn lessons from this for the future.
"Children should enjoy school life and I hope this is the case for pupils at Buchanan and St Ambrose high schools."
North Lanarkshire Council said it welcomed the findings and would put all the report's recommendations into place.
The council's enterprise and communities director Robert Steenson said they accept all of the report, 'particularly the finding that the school is safe and that the pupils can return to school next week because it's a high performing school and we want to get back to normal as quickly as we possibly can."
He also accepts the report's criticism of the council but believes that parents and teachers now need to look forward.
He said: "What I'd like to see happening now is that the group of those interested in the wider school community - those parents, the pupils, trade unions, the staff - get together as recommended in the report and actually start to rebuild trust which is required for both of these schools to operate effectively."
Asked what he would say to parents who remain unconvinced, he added: "Please read the report. Please look at the facts which are expressed and please come to your conclusions and hopefully having read that report you'll see that there are no risks to your children going back to school, that it is a safe environment and that we can get back to normal as quickly as we possibly can."
Professor Andrew Watterson of Stirling University's faculty of health science told STV News: "The report has covered a great deal of ground in a very quick time.
"I think there's still some way to go and more work needs to be done.
"Once it's fully digested it may be that most of the questions are answered but at the moment they haven't all been so I would be looking in the future for more activity, more monitoring, more surveillance to make sure everything's okay.
"We haven't seen the detailed analysis of the cancer cluster, we haven't seen details about necessarily all the chemicals that have been tested and the decision making.
"We haven't yet seen - which is probably the most important thing for the parents - details about how the assessments were made that there were no health problems. That needs to be transparent and out in the public domain."