Acting against the complaints of illegal groundwater extraction by builders in Delhi -NCR region, the National Green Tribunal (NGT) on Wednesday asked the local commissioners appointed by it to do surprise checks and to submit their reports within two weeks.Setting the next date of hearing on August 7, a bench headed by NGT chairperson Justice Swatanter Kumar said, “One local commissioner has filed his report. All the remaining local commissioners are directed to file their reports within two weeks.”