The site investigation report shall include a summary of subsurface explorations and sampling conducted at the site and off-site surrounding area including:

1. (a) A description of test pits, borings, and soil gas monitoring points, including:

   1. (1) Soil sample descriptions according to:

      1. a. Unified Soil Classification System;
      2. b. Burmister Classification System;
      3. c. “Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System),” document identification number ASTM D2487-17 (2025), available as indicated in Appendix B; or
      4. d. “Standard Practice for Description and Identification of Soils (Visual Manual Method),” document identification number ASTM D2488-17e1, dated 2018, available as indicated in Appendix B;
   2. (2) Drilling methods;
   3. (3) “N-values” according to “Standard Test Method for Standard Penetration Test and Split Barrel Sampling of Soil,” document identification number ASTM D1586/D1586M-18e1, dated 2022, available as indicated in Appendix B; and
   4. (4) Water table observations
2. (b) A description of monitoring wells, and well development activities, including well construction details of existing monitoring wells, top of well casing elevations, and measured depth to water table from top of casing;
3. (c) A description of water table elevation observations, organic vapor analyzer results, and odors noted;
4. (d) A copy of the site plan showing the orientation of the graphical geologic cross section(s) and the location of test pits, borings, monitoring wells, and other sources of geologic information for the site;

5. (e) Groundwater, soil, air, soil gas, sediment, surface water, and water supply well sampling data, as applicable, including:

   1. (1) Sampling methodologies;
   2. (2) Analytical results for a minimum of 2 sets of samples collected at least 2 weeks apart for all monitoring wells, surface water sampling points, and water supply wells;
   3. (3) At sites where groundwater contamination has been detected, samples collected from water supply wells at risk;

6. (f) One or more tables that summarize all current and historical groundwater, soil, surface water, and water supply well elevation and analytical data including:

   1. (1) Sample locations;
   2. (2) Sample dates;
   3. (3) Groundwater elevations;
   4. (4) Top of well casing elevations surveyed to the benchmark required under Env-Or 606.04(m)(4);
   5. (5) Measured depth to water table from top of casing;
   6. (6) Chemicals detected including the analytical detection limits;
   7. (7) Chemical concentrations;
   8. (8) Chemicals that exceed regulatory limits;
   9. (9) Depth of NAPL from top of casing, if present;
   10. (10) Thickness of NAPL, if present; and
   11. (11) Observation of oil sheen, if present;

7. (g) One or more tables that summarize historic groundwater, soil, surface water, and water supply well analytical data including:

   1. (1) Sample locations;
   2. (2) Sample dates; and
   3. (3) Chemical concentrations; and

8. (h) A description of all other methods used to evaluate subsurface conditions as appropriate, such as:

   1. (1) Geophysical methods;
   2. (2) Geochemical analyses;
   3. (3) Cone penetrometer; and
   4. (4) Fracture trace and photo lineament analysis.
9. (i) An evaluation of any known conditions or findings that might affect the validity of analytical data, including a review of quality assurance and quality control results reported during the monitoring period.

Source. (See Revision Note at chapter heading for Env-Or 600) #8812, eff 2-1-07; ss by #10831, eff 6-1-15; ss by #14419, eff 11-4-25, EXPIRES: 11-4-35