Air Handler Pan Overflow.
The air handler that was located in the attic leaked because the drain line was blocked. The water overflowed from the unit pouring and pooling onto the drywall below. That drywall below is the Pantry. Sadly this property was only seasonally occupied and when the damage was discovered the mold was growing from ceiling down walls to floor. Very heavy musty smell which became more pungent closer to Pantry Doors.
A licensed HVAC tech first resolved the water source by fixing the overflow. A snail shell was found in the line causing a blockage and not allowing the water to escape out the drain line.
The closet area was contained as not to cross contaminate the other portions of the house. After a proper cleaning that includes use a hepa vacuums, application of anti-microbial, an application of an encapsulant, and scrubbing the air, the closet area was tested for clearance.
At the conclusion of the remediation an independent third party laboratory determined the remediation was successful and provided a post remediation clearance report.