The 10Be and Be contents of 22 samples taken from seven locations in the Maurice River-Union Lake system of southern New Jersey are reported. Bulk 10Be contents range from 0.05 to 2.7 dpm/kg and Be from <0.1 to 2 ppm. Silicate minerals separated from Union Lake sediments appear to have a constant surface concentration of ~5¿105 atom 10Be/cm2. Organic material is greatly enriched in Be: Hand-picked samples contain over 10 dpm/kg of 10Be and 5 ppm of Be. The deposition rate of 10Be in Union Lake is ~1 atom/cm2 s.