Two new Resource Conservation and Recovery Act (RCRA) groundwater monitoring wells were installed at the single-shell tank farm Waste Management Area (WMA) B-BX-BY during December 1999 through February 2000 in fulfillment of Tri-Party Agreement (Ecology 1996) Milestone M-24-45. The wells are 299-E33-334 and 299-E33-335. These wells were installed in support of the WMA B-BX-BY assessment to track the movement of contaminant plumes that appear to be entering the WMA from the northeast. Well 299-E33-334 is located outside the southwest corner of the 241-BX tank farm and well 299-E33-335 is located south of the 241-BX tank farm. The locations of all wells in the extended monitoring network for WMA B-BX-BY are shown on Figure 1. The new wells were constructed to the specifications and requirements described in Washington Administrative Code (WAC) 173-160 and WAC 173-303, in the assessment groundwater monitoring plan (Narbutovskih 2000), and in the description of work for well drilling and installation. This document compiles information on the drilling, construction, well development, pump installation, and sampling activities applicable to wells 299-E33-334 and 299-E33-335. Appendix A contains copies of the Well Summary Sheets (as-built diagrams), the Well Construction Summary Reports, and the geologist' logs. Appendix B contains results of laboratory analyses of moisture content on samples from 299-E33-334 (moisture data were not collected from well 299-E33-335). Appendix C contains borehole geophysical logs and Appendix D contains analytical results from groundwater samples obtained during well construction. Additional documentation concerning well construction is on file with Bechtel Hanford, Inc. English units are used in this report because that is the system of units used by drillers to measure and report depths and well construction details. Conversion to metric is made by multiplying feet by 0.3048 to obtain meters or multiplying inches by 2.54 to obtain centimeters.