UPRR railroad operations in Pocatello began with establishment of a railroad terminal in 1882. As rail operations spread out around the terminal, the city grew around the railroad yard. The railroad yard served as a hub of maintenance and operations for both passenger and freight trains for many years.

Rail yard facilities included a roundhouse and turntable, transfer table, powerhouse, fueling stations, railcar cleaning stations, engine and brake repair shops, coal tipple, smithy, switching stations, humpyard, wheel shop, back shop, both above and underground storage tanks, and a wastewater treatment facility. A separate area within the main rail yard was used by Pacific Fruit Express, a subsidiary of UPRR, for maintenance and operation of refrigerated railcars. The railroad operated and maintained coal-fired steam locomotives until the introduction of diesel engines in the early 1940s. Although many of the historical facilities and maintenance and operation activities at the Pocatello rail yard have been relocated, the site remains an active rail yard.

On June 26, 2003, DEQ entered into an agreement with the U. S. Environmental Protection Agency (EPA) to provide lead status for the UPRR site investigation, Pocatello rail yard. This conditional agreement is valid provided the site investigation is conducted according to EPA guidance.

Responsibility for designing and implementing all site investigation activities rests with UPRR and its contractors. DEQ's role is to review, approve, and monitor the activities. EPA also will be included in the review and approval process.

The UPRR site investigation will be implemented through the following dual regulatory process:

• The site investigation will be conducted according to EPA Guidance for Performing Site Investigations under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) including sampling to provide data for the EPA Hazard Ranking System (HRS). Using the HRS, EPA will evaluate data collected during the site investigation.

• Upon completion of the site investigation phase, and depending upon whether contamination is detected and to what degree, the next anticipated phase may consist of submittal of a remedial action plan by UPRR to DEQ. Alternatively, based upon the results of the HRS, EPA may decide to add the UPRR Pocatello rail yard to the National Priorities List and proceed with a Remedial Investigation/Feasibility Study.

DEQ has received and, as of June 21, 2004, approved the Final Site Investigation Work Plan. A copy of the plan may be viewed at DEQ's Pocatello Regional Office, 444 Hospital Way, #300. The Site Inspection Sampling and Analysis Plan was approved by DEQ on September 13, 2004. Groundwater monitoring well installation began the week of September 20, and field sampling activities the following week.

Groundwater monitoring wells will be installed at the site and strategically placed downgradient of ground water flow. Surface soil, subsurface soil, and ground water samples will be collected on-site and analyzed for a wide array of chemicals. To determine if UPRR operations and activities have impacted the Portneuf River, water and sediment samples will collected near the UPRR wastewater treatment facility and at select city of Pocatello outfalls for stormwater drains that pass through the rail yard site.

It is important to note that if contamination is discovered that poses an imminent threat to human health or the environment, removal actions can occur at any point during the investigation.