QA-Pre-bid meeting at Einstein Mine.docx

16 Aug 2022 Q&A during the pre-bid meeting for Einstein Mine -Silver Mines Recreation Area Ironton, MO

1. Attachment E-Past performance questionnaire needs to be sent out to contractors.

2. What is the recommended timeline for the work to be done? No later than 60 days after the Notice to proceeded is issued, but generally in mid-late Fall 2022-Winter 2023 during leaf off. Campground season is closed officially and host leaves 30 Sept 2022. First come first serve camping is still available through October.

3. Are all of the DU’s on FS property? Yes. One DU does, DU #16 bumps up to a boundary with private property.

4. Is it acceptable to collect geodata for GIS work while on this pre-bid inspection? Yes.

5. Are the boundaries of the DU’s set in place from a visual inspection of features? Yes, areas defined have topographic features attributing to their shape and area. Drainage channels, old roadbeds, tailings/chat piles, and proximity to adits.

6. Is the sampling to stay within the boundaries of the DU’s? Yes. We are open to discussion if site evidence suggests the existing DU’s need to be re-delineated.

7. There is a lot of solid bedrock in place, and most samples appear to be very coarse. Can the samples be from very coarse sediment? No, the fine-grained sediments are the main target of this sampling effort. Efforts will need to be made to locate sample locations in and around course material to sample fines.

8. What about distribution of sampling with each DU, should it be the same throughout the whole site? DU specific constraints exist throughout the site. Measures will need to be taken to adjust increment locations based on the presence of bedrock or other features. Generally, there should be a relatively even and similar distribution of increments for each DU. The goal of the increment distribution is to include a thorough representation of the entire DU.

9. If there aren’t enough fines, is it okay to sample the coarse material? Have it crushed? No, the purpose of this sampling project is to sample the fine materials that exist on the site.

10. Is Pb the only COC? Lead is not the only contaminate of concern but does tend to be a driver and a good surrogate on many of our sites. Per the SOW we will be analyzing and considering all TAL contaminates, except for Mercury and Cyanide, in the SI.

11. Is there a requirement of PPE? Safety decisions for execution of this project are the responsibility of the contractor. Contractor’s Health and Safety Plan and implementation are not pay items under this contract.

12. Highest level collected by the USFS with the XRF? ~5,000 ppm Pb

13. Will participation in the sampling exclude the contractor from future work on the site? No.

14. There is a kick-off call with the bidders and the laboratory processing the samples to discuss the work.

15. Just encore sampling, or will there be soil probing to a certain depth? The focus is on the areal extent of the contamination.

16. Will ATV use be allowed for the work? Permission for ATV use is not guaranteed and is still being considered. Individual sampling locations may not be easily accessible due to heavy vegetation, rough terrain, or water courses.

17. Will there be toxicity characteristic leaching procedure (TCLP) sampling? No, no sampling for hazardous waste characteristics at this time.

18. There is an archaeological site present, this area lies within the Trail of Tears corridor. Any future archaeology work will be handled by USFS scientists.

19. There are currently no endangered species to be aware of in the area that is to be sampled.