US rules in National Electrical Code are that CATV and telephone conductors cannot be in the same conduit. The same trench but not the same conduit. NEC 725.55, 800.47, 800.133, 820.47, and 820.133 effectively prohibit this. Also, the electrical utility would want to put antitampering seals on any pull box that is on the supply side of a meter and they would object to giving permission to break seals to maintain anything other than the electrical service conductors, meter sockets, and so forth. There are just too many safety and practical considerations.
In actuality, putting 2 or 3 different kinds of electrical conductors in the same conduit would prevent withdrawal and replacement of broken conductors or doing an upgrade. What you need to do is to install 3 conduits and 2 sets of handholes.
You need 1 conduit ( about 4 inch ) and 1 set of handholes for the power condutors. Because of your distance from the power source you need 400 amp service conductors to get adequate voltage drop performance when starting a central air conditioner or subersible well pump. ( 4 inch well pump motors are up in the code S starting current range. ) You need at least 500 KCM copper or 750 KCM aluminum for your distance. You might need to instead use 2 smaller power conduits using 2 conductors in parallel per phase and neutral. Using an oversize conduit will make wire pulling a LOT easier and will save on screaming as well as wire pulling labor. Stuffing a conduit to only 3/4 of what NEC allows almost always pays because of lower wire pulling labor.
You would then need two 1 inch conduits for the telephone and CATV. Telephone and CATV can share the same handholes and pull boxes unless there is somehow a major amount of labor friction. Communications Workers of America, Utility Workers, and Teamsters happen to like each other as opposed to how UAW has blacklisted everybody who has a Teamsters card.
The telephone and CATV companies around here never object to using the same trench as a power service if the power service is in PVC conduit.
Modern underground telephone service cables have a copper clad steel foil shield that is grounded at the protector block so you should not have too many problems with noise frommthe adjacent power lines.
Where you must have lots of separation is between natural gas lines and anything with electricity in it. In the early 1980s 2 feet of vertical or horizontal separation from natural gas and electrical stuff was required but since then the separation distance is more like 3 feet. You will have to ask each utility and the building inspectors how much they want between natural gas and electrical stuff.
Spearation from water services and sanitary sewers is also a consideration. In the case of water services a water main break could force its way into electrical stuff. In both cases they usually want a certain amount of horizontal separation from electrical and natural gas line so that they can dig up the water and sewer lines for replacement.
