Analyze Activity 2001 in the "Normal" Schedule:

Activity 2001 ("River Diversion Stage 1") has a duration of 92 days under the "Normal" schedule.

The logic column shows it has a Successor ID of 2002, and a Finish-to-Start (FS) relationship with no

lag. This indicates that Activity 2002 will begin immediately after Activity 2001 finishes.

Identify Concurrent Activities Using the Schedule Logic:

To determine concurrency, we need to look for activities that overlap in time with Activity 2001

during its duration. Concurrent activities must either:

Start before Activity 2001 finishes, or

Finish after Activity 2001 starts.

Review Activities in the Normal Schedule:

Activity 1001 ("Preliminary Civil Work"):

Has a duration of 85 days, starts before Activity 2001, and overlaps with it.

Logic: Its successor is Activity 2001 (Start-to-Start [SS] relationship), confirming the overlap.

Activity 1000 ("General Conditions"):

Duration is 1072 days. However, this is an overarching activity, and its inclusion is not specific to

being concurrent with Activity 2001.

Activity 7001 ("Permanent Roads"):

Starts much later, after Activity 2001 ends, and thus is not concurrent.

Activity 2003 ("River Diversion Dam"):

Starts after Activity 2001 completes (FS relationship), so it is not concurrent.

Conclusion:

The only activity that overlaps and runs concurrently with Activity 2001 in the "Normal" schedule is

Activity 1001.

Reference:

PSP Study Guide (2019), Chapter on Schedule Development, Section 2.2.4 – Relationships: Discusses

how Start-to-Start (SS) and other dependencies impact concurrency.

AACE Recommended Practice 10S-90: "Cost Engineering Terminology" for definitions of concurrent

activities.