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Soil Investigations for Data Collection in the Delta Initial Study/Proposed Mitigated Negative Declaration 194 2”) is smaller in size than any soil disturbance archaeological testing methodology would create in testing for subsurface deposits, and therefore CPTs are less impact to a site than testing for the presence or absence of subsurface archaeological deposits. Given this, the soil disturbance from a CPT is would not produce a significant impact to previously unidentified subsurface deposits. 3. Boring units do extract soil, but the diameter of a bore-hole (maximum 8”) and a core sample is significantly smaller than what is created during subsurface archaeological testing for the presence or absence of resources. Standard sampling methods include Standard Penetration Tests which produce a core with an approximate diameter of 1.5”, Modified California Sampler produces a core with an approximate maximum diameter of 2.5”, Pitcher Barrel Samplers produce a core with an approximate maximum diameter of 3”, and Shelby tube style samplers (i.e. 101mm Geobarrel and 134mm Geobarrel shelly tubes) with an approximate range in core diameter between 2” to 5”. a. Many of these cores would not be processed in such a way that would allow the soil of the core to be examined immediately after soil extraction. As such, a monitor would be unlikely to have the opportunity to examine a core. b. These core sizes are not large enough to produce a notable disturbance to subsurface archaeological deposits. The risk of substantial impacts to a previously unknown subsurface deposit, given the size of the boreholes, is extremely low. Given the low risks of substantial subsurface impacts and small sizes of these cores, an archaeological monitor or tribal monitor during the boring activities would not be warranted. c. In the event a core is processed in such a way that the soil would be viewable while in the field, cultural sensitivity training for the environmental monitor and the field crew would be designed to aid in the identification of cultural material that could come out of the core (e.g., lithics and organic material less than 5” in maximum width within the geological time lens between the late Pleistocene and modern surface). 4. In the unlikely event a potential tribal cultural resource is identified through archaeological surveys or during field activities, the material would be reported to the consulting tribe with interest in the area and a plan would be made in consultation with the consulting tribe/tribes, in accordance with MM-CUL-2. In the case of human remains, MM-CUL-3 would be followed. During consultation, discussion was also had about investigations, data on Delta geology may support a tribes understanding of historic landscapes, the depths of soils with potential to hold cultural and potential tribal cultural resources, and information on potential tribal cultural resources located throughout the Proposed Project Study Area. Providing data from the soil investigations would help tribes better identify tribal cultural resources for future projects within the study area region while causing non-significant