NAC International led a series A round for nuclear waste manager Deep Isolation following an initial partnership formed last year.

Deep Isolation, a US-based developer of nuclear fuel disposal technology, closed a $20m series A round today led by NAC International, a radioactive material services subsidiary of industrial and engineering firm Hitachi Zosen.

Founded in 2016, Deep Isolation deposits cannisters containing nuclear waste in boreholes penetrating deep beneath the ground using its horizontal drilling technology, a method it claims is safer than existing alternatives.

NAC will assign an as-yet-unnamed representative to Deep Isolation’s board of directors in conjunction with its…