Description
Published:Vol. 1, no. 1 (Jan. 1993)-v. 9, no. 4 (Oct. 2001).
Item Description:Title from title screen (viewed May 9, 2001).
Some issues distributed to depository libraries in paper form, 199 -<2001>.
Address: National Water Quality Laboratory, USGS, Box 25046, MS 407, Denver Federal Center, Denver, CO 80225-0046.
At head of title: National Water Quality Laboratory.
Not distributed to depository libraries in physical form, 2001-
Electronic resource.
Publication Frequency:Quarterly