I've been using Wind River for about 5 years to service my septic system (in Plympton MA). The first time I called the system hadn't been serviced in several years, and there was a problem. They sent out two ""technicians"" the next day, and it turned out that it was just a broken filter, which they fixed easily.
A year later it was just a routine pumping. After the routine pumping in 2009 they said I could wait 18 months until the next cleaning, and in May 2011 they said I could wait two years ... they really do customize the amount of service you need based on your usage.
They do push the shock treatment at the time of service (about $100) and the CCLS treatment into the toilet every two months (also about $100 a year). So that costs a bit, but the system seems to be trouble free now. They do give little discounts.
They come within the agreed-upon time window (though I will say that 7am-noon is rather a large window), and once you get into the routine, pumping takes only about half an hour.
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