Engine Oil Leaking problems of the 1998 Buick Riviera

It started out as a small oil leak, but I recently noticed the leak has expanded significantly. It's difficult to pinpoint the leak, but an oil pan under the car shows significant puddling of oil. A sealer/conditioner doesn't appear to have been affected. While online, I noted that the 3800cc 3. 8l engine seems notorious for this problem, and other models of gm cars appear to be subject to a recall. Not so the Buick, which to me, has the same engine. Given that is is known now, I'm concerned that this low production vehicle was left out of the recall and should be included. Puddle of oil photo enclosed. This condition is most noticeable while the vehicle is stationary.