DEAR SAM: In the event of an electrical power blackout, what provisions can be made for a basement sump pump which provides for drainage because of a high water table? You have already written about the use of a boat pump, connected to a 12 volt battery. Any other suggestions?

ANSWER: Yes and according to the literature of Penberthy Division, Houdaille Industries, Inc., ProPhetstown, Ill, 61277, you may want to own their non-electric sump pump "as a standby pump to handle over-load on primary pump or pumping during power failures." It is operated by either water or steam.

As a standby, during power failure, the Penberthy pump will automatically take over when the water rises above the level of th electric pump, or can substitute for it.

For specifications and description write to the manufacturer for Form No. G-74 concerning Models IR and 2R, and ask for the name of your local dealer.

DEAR SAM: Last October I wrote you inquiring about the use of an antifreeze solution in my forced hot water system. I received your reply in November, but in the meantime I wrote to Union Carbide Corp. in Tarrytown, N.Y., which advised me that they had "limited, but very favorable experience with the use of Prestone II Winter Summer Concentrate in conventional hot water systems." Before I left for Florida, I had my plumber fill the system with sufficient Prestone to bring the solution to minus 10 degrees Fahrenheit. I turned the heat off for the month I was away and when I returned home, I turned it on. The system functioned perfectly. With the severe winter that prevailed, it was a substantial saving in fuel.

ANSWER: I recall my letter advised to the contrary, since I was concerned not only about the water in the heating system, but also water in the domestic storage tank and in the traps of the various fixtures, which would likewise have to be removed or mixed with an antifreeze.

Of course, you had a good plumber who tested the baseboard convectors well. I recently was told by a friend that his neighbor had a less happy story: The plumber drained the hot water system, etc., but when it was time to replenish the water, it appears that one convector had developed a freeze-up crack and it flooded his home when the water was turned on. I don't know whether this accident would warrant usual claims, but the homeowner collected from the insurance company on his homeowners policy.

Samuel Fishlyn welcomes letters on home improvements and will include those of general interest within the limited space. Write to him at Box 62, Newton Centre, Mass. 02159. For a personal reply, please include a self-addressed, stamped envelope.