Here's the skinny on the top 4 hotly contested sites for a new Civic campus

In the week since the National Capital Commission'sboard announced its choice, surprised Ottawa Hospital officialsand local politicians have been vocal aboutwhythey find Tunney'sPasture to be unworkable as a future site for a new Civic campus.

So, howdid the NCCsettle on Tunney's Pasture, anyway?

It started a review at the end of June at the request of the federal Liberal government, which was under pressure to conduct a process that included public consultation.

The NCC spent the summer going over whatthe hospital wanted out of a site: a central location that'sideally 24 hectares and square or rectangular, with good road and transit access and about 10 hectares for parking.

The NCC developed its own list of 21 criteriato evaluate a dozen sites, addinghow the federal government plansto use its land, heritage and environmental interests,and how the sitesintegratewith the fabric of the city.It heard from more than7,000 people in public consultations. A panel of NCC board members, architecture experts and others scored the sites.

Here, for the record, is the NCC's list of pros and cons for the most hotly debated of the 12 sites.

Site 1:Tunney's Pasture

The NCC looked at the western half of the public service complex, which has several parking lots. It said the federal government intended to sell off this section anyway as part of its 2012Tunney's Pasture master plan.

The goal back then was to make a profit by selling the land to developers for office and residential space, which would involve moving the 4,000public servants who currently work there.

Size: 21 hectares. The NCC does not deemthe land ofnationalinterest, nor does it needitforlong-term federal plans.

Site 9:Central Experimental Farm, atCarlingand Holland avenues

This is the site that former Conservative cabinet minister John Baird offered the Ottawa Hospital in a surprise announcement in November 2014, and it overlaps with Site 10.

Size: 22 hectares. The NCC deems the land ofnationalinterest,or needs itforlong-term federal plans.

Site 10:Central Experimental Farm, central parcel

The middle of the three sites on the experimental farmhouses three federal buildings used byAgriculture and Agri-Food Canadaand overlaps with Site 9.On Nov. 30, the department confirmed the portion along Carling Avenue can't be used for scientific research because the soil has been made poor by road salt.

Size: 26 hectares. The NCC deems the land of national interest, or needs itfor long-term federal plans.

Site 11:Central Experimental Farm, former Sir John Carlingbuilding

This site would take in a parking lot often used by skaters walking over to the Rideau Canal, as well as a field on the other side of Ottawa's Trillium line. The site has a hill of trees behind which the Sir John Carling building used to stand before it was demolished in a spectacular explosion in 2014.

The boundaries of the site were reconfigured so that the Dominion Observatory, a classified federal heritage building, would not be part of a hospital site.

"The Sir John Carling site, which is site 11, is a very good option for usand it wouldn't interfere with any research going on at the experimental farm," Ottawa board chair Jamie McCracken told CBC's Ottawa Morning on Nov. 30.

Size: 20 hectares. The NCC deems the land ofnationalinterest,or needs itforlong-term federal plans.