In the present paper we described a 36 years old female, who expelled approximately 2000 stones from the urinary tract during the last 18 years. According to the clinical and laboratory tests the lithogenic factors such as abnormalities of calcium, phosphate, oxalate, magnesium and purine metabolism were excluded. The cystinuria and other forms of tubular nephropathies did not exist. Taking into account two following facts: 1) no evidence of renal calculi when the patient was outside her own house and 2) very high concentration of calcium in her home tap water, the role of environmental factors in the pathogenesis of nephrolithiasis in presented patient is very likely.