Appendix 8 to Subpart A of Part 435—Reference C16-C18 Internal Olefin Drilling Fluid Formulation
The reference C16-C18 internal olefin drilling fluid used to determine the drilling fluid sediment toxicity ratio and compliance with the BAT sediment toxicity discharge limitation (see § 435.13) and NSPS (see § 435.15) shall be formulated to meet the specifications in Table 1 of this appendix.
Drilling fluid sediment toxicity ratio = 4-day LC5. of C16-C18 internal olefin drilling fluid/4-day LC5. of drilling fluid removed from drill cuttings at the solids control equipment as determined by EPA Method 1644: “Method for Conducting a Sediment Toxicity Test with Leptocheirus plumulosus and Non-Aqueous Drilling Fluids or Synthetic-Based Drilling Muds” after sediment preparation procedures specified in EPA Method 1646, which are published as appendices to Subpart A of this part and in “Analytic Methods for the Oil and Gas Extraction Point Source Category,” EPA-821-R-11-004. See § 435.11(ee) and (uu).
| Mud weight of SBF discharged with cuttings (pounds per gallon) | Reference C16-C18 IOs SBF (pounds per gallon) | Reference C16-C18 IOs SBF synthetic to water ratio (%) |
|---|---|---|
| 8.5-11 | 9.0 | 75/25 |
| >11-14 | 11.5 | 80/20 |
| >14 | 14.5 | 85/15 |
| Plastic Viscosity (PV), centipoise (cP) | 12-30 | |
| Yield Point (YP), pounds/100 sq. ft | 10-20 | |
| 10-second gel, pounds/100 sq. ft | 8-15 | |
| 10-minute gel, pounds/100 sq. ft | 12-30 | |
| Electrical stability, V | >300 |
[66 FR 6901, Jan. 22, 2001, as amended at 77 FR 29845, May 18, 2012]