McKinsey Solve · practice simulation

Sea Wolf

A coaster has run aground off the Kestrel coast and diesel is spreading along the shore. The response team wants to treat it biologically: seed each affected site with a blend of microbes that will survive there and break the fuel down, rather than dredge.

Time: 30 min
Sites: 3
Microbes a site: 10
Scores: 2

Instructions run off the clock.

Your objective

Screen the database for each site, build its prospect pool, and average three microbes into the strongest treatment you can, across all three sites in 30 minutes.

Three sites need a treatment, worked one after another: the open Kestrel Shelf, the brackish Merlin Sound and the harbour mouth at Osprey Reach. Each has its own tolerances, and a trait that helps at one site can be a problem at the next.

Site 1
Kestrel Shelf
Open sandbank, 15 to 25 metres
Site 2
Merlin Sound
Brackish tidal inlet with seagrass
Site 3
Osprey Reach
Harbour mouth and quays

How it runs

Three sites, worked in order. You see the full profile of the site you are on, and one range of the next.

1
Categorise
Review 10 microbes one at a time, and send each to this site, the next site or back to the database.
2
Add prospects
Choose 4 more from a reserve to widen what you can build with.
3
Build the treatment
Average 3 microbes from your pool into a treatment that has to land inside every range.
4
Move to the next site
Microbes you routed ahead are waiting there. Repeat until all three sites are treated.

How it is scored

Product score

The treatments

Each average inside the site range earns 2, each microbe with the desired trait earns 1, and one undesired trait spoils the treatment. Measured against the best each site allowed.

Process score

The screening

How many of the 30 categorisation calls you got right. A missed microbe also costs you later, when the treatment that needed it is out of reach.

Sea Wolf

Your objective

How it runs

Categorise

Add prospects

Build the treatment

Move to the next site

How it is scored