Narrative:

I was working the final sector on a runway 10 flow into portland. I noticed two primary targets north of my airspace heading southbound. I did a minimum separation function on the stars display and decided that the targets were likely going to be close to my B737 jet. But the targets were spaced out in such a way that I couldn't extend the B737 on the downwind to miss the first target; because it would likely merge with the second target. I descended the B737 jet and turned base; hoping to turn final south of the two targets. I called traffic at least 3 or 4 times to the B737 jet and the pilot never got either target in sight. I then called local 2 and asked if they could see any low level aircraft out to the west. They said no. The target eventually got to within .333 of a mile to the B737 at about a 6 mile final before it crossed final and headed to the southeast. The second target did not cross final and instead appeared to land at [ a satellite] airport.this was a normal/daily operation at kpdx. Unidentified targets; both primary targets and 1200 codes; cross portland final all day constantly and they hardly ever call approach for flight following. One day this is going to end in a near midair or even worse. There are a lot of controllers here [submitting safety reports on] these events and we get little to no feedback. Management seems indifferent as well. What do you want us to do? One day a collision is going to be unavoidable without an airspace design change. It really is.

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Original NASA ASRS Text

Title: P80 TRACON Controller reported the PDX class C airspace does not provide separation to arrivals from non-participating air traffic.

Narrative: I was working the final sector on a runway 10 flow into Portland. I noticed two primary targets north of my airspace heading southbound. I did a minimum separation function on the stars display and decided that the targets were likely going to be close to my B737 jet. But the targets were spaced out in such a way that I couldn't extend the B737 on the downwind to miss the first target; because it would likely merge with the second target. I descended the B737 jet and turned base; hoping to turn final south of the two targets. I called traffic at least 3 or 4 times to the B737 jet and the pilot never got either target in sight. I then called local 2 and asked if they could see any low level aircraft out to the west. They said no. The target eventually got to within .333 of a mile to the B737 at about a 6 mile final before it crossed final and headed to the southeast. The second target did not cross final and instead appeared to land at [ a satellite] airport.This was a normal/daily operation at KPDX. Unidentified targets; both primary targets and 1200 codes; cross Portland final all day constantly and they hardly ever call approach for flight following. One day this is going to end in a near midair or even worse. There are a lot of controllers here [submitting safety reports on] these events and we get little to no feedback. Management seems indifferent as well. What do you want us to do? One day a collision is going to be unavoidable without an airspace design change. It really is.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.