I only see two problems with the aforementioned solution to this problem. Not only is it PROHIBITED BY CODE in all likelihood it will make the problem worse rather than correct it. The Plumbing Codes dictate that whenever any pipe is run under or through a footer or footer wall the pipe MUST BE sleeved and there is to be no direct contact between any pipe and masonry materials. To create a sleeve we must first select a short section of pipe at least two nominal trade sizes larger than the desired pipe and long enough to extend through the wall with 2 to 3" extending out on either side. The sleeve pipe may be cast into the concrete, mortared in when the wall is laid or you may make a hole and install it after the wall is constructed. The sleeve may be sealed to the wall by means of pitch, tar, expansion foam or any other locally approved suitable means. Once the sleeve is in place the desired pipe is to be passed through the sleeve and the space between the outer wall of the desired pipe and the inner wall of the sleeve is to be filled with expansion foam. The purpose of the sleeve is twofold. 1. Pipe has a much greater coefficient of linear thermal expansion than does concrete, cement or other masonry materials. Whenever pipe is in direct contact with masonry materials as the pipe expands or contracts it rubs against the masonry material having the same end effect as repeatedly rubbing the pipe with an abrasive grinder. 2. If a metal pipe is in direct contact with any form of cement, mortar or other masonry materials the lime in the mortar reacts with the metal in the pipe and causes severe corrosion of the pipe wall. Not only will cement or even hydraulic cement not effect a water tight seal, digging on the outside of the wall will most likely make the problem even worse. No doubt, by now the soil on the exterior of your basement wall settled to a point were it has achieved maximum compaction. If you were to dig up that soil, attempt a repair from the outside, then backfill the hole, the soil immediately around the problem would be loose and would offer very little resistance to surface water soaking down to the pipe. No doubt it would be very difficult to install a sleeve at this point however you can do the next best thing. Working from the inside clean out as much dirt and debris as possible to enlarge the hole around the pipe, then using a can of expansion foam that has a flexible tube on the nozzle, insert the tube as deep in the hole as possible and fill the hole with as much foam as you can get in, then continue spraying the foam as you pull the tube out. The foam will adhere to both the masonry material and the pipe wall; yet still provide a flexible material that will compensate for the thermal expansion or contraction of the pipe.

hendricus: I thought of that, but I don't have any straws. But even with that, the space available to work with is minimal. I can just fit my hand in the area, yet it's about a forearm length away. It will be easier to climb under the porch. (I say that now...wait till I see the bugs.) davidandkasie: There's plenty of other proper vents provided for that purpose. This is obviously some kind of construction flub or shortcut. Our house was built back when the inspectors were known for doing curbside inspections. Fortunately this doesn't seem to have caused any structural issues that I can detect. I'm actually making slow progress towards getting the crawlspace to be sealed. We monitor the humidity down there with a digital remote sensor and the winter is the best time to start some of this work due to the dryer weather.

Uhhh GN Builders, apparently, you are in an area where there are basements. That just isnt true in a lot of places. There are a few basements in my area, but, they are very few and very hard to find. Most houses in this area, have a foundation the correct depth into the ground, and a house is built on top of that foundation. There are vents in that foundation, and there is an opening, for a door of sorts into that crawl space. Some houses are really crawl, like belly crawl, some you can hunch over and walk under, and some like mine, you can crawl around on you knees, and not have a problem bumping your head, etc. Yes, the water lines are in that crawl space, and so are heating/coolng duct work. Some even have their hot water heater in the crawl space.The height of the crawl space, depends upon the land the house is built on. Some houses have a very high crawl space on one side, and by the time you get to the other side, it is a belly crawl. It is the way houses are built, and I am guessing, you have no experience with them.

@ptreckel I doubt it had radiators. Although it would make sense for the age, I don't see any holes through the original floorboards to the 1st floor that could have been used for the pipes. @Sammy So your telling me that cities had underground oil lines before they had underground natural gas lines? I guess it's possible. There definitely wasn't an outdoor oil tank on site. I remember reading that most homes before the 70s had gas meters inside, but then they were moved outside for some reason.