Sump pumps keeps running after a rain or when snow is melting

We have 2 sump pumps. Each time it rained last year, the sump pump closer to our back yard would run every 20s for 3-4 days. The last 3 days as the snow melted, this sump pump has been running at the same regularity. In contrast, the sump pump closer to the front of our house runs very infrequently.

We live in Wilmette, IL.

Is there something wrong that is causing our rear sump pump to be running so frequently?