Asbestos Abatement and Insulation Services (AAIS) Corporation and Bestech Inc. of Ellington are two of the four companies that the state Department of Administrative Services chose in 2017 to be on an exclusive list of contractors that would handle all abatement work on state buildings. The list was originally intended for state agencies and municipalities that needed emergency work done. Diamantis’ team was in charge of the contract, state officials said Friday. AAIS and Bestech were among the names that federal authorities asked officials to search for in a subpoena issued in October that centers on Diamantis. An analysis by the CT Mirror shows that AAIS and Bestech got all but 15 of the 284 purchase orders issued by the state for hazardous waste disposal and demolition from fiscal year 2017 through 2022 — contracts that are paid for by the state and not tied to school construction jobs.