$1400 each seems like a lot depending on the condition. The lids are usually the culprit, although you can also get seepage in the joint between the riser sections. Some of the old style lids actually have holes in the top (for grabbing and pulling), so you need to make sure those are plugged and sealed. Also, seal around the lids with the rope style sealant or caulk (check USA Bluebook). If it is a lid you don’t pull very often put lots of caulk around it. (Silicone)
Other sources of infiltration - the risers on each lot. If you have empty lots, make sure the sewer risers are all located and sealed. Sometimes they are broken under the ground so you make have to do some digging to check for breaks and cracks, etc. It is an elusive problem - good luck.
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