1

TO: Tina Ndoh , U

. S

. EPA/OAQPS/SPPD

- Minerals and Manufacturing Group

FROM: Eastern Research Group, Inc.

DATE: March 24 , 2015

SUBJECT: Notes from Meeting with Florida DEP Regarding Gypsum Dewatering Stack and

Cooling Pond Management Plan

SUMMARY

The EPA and ERG visited the Florida Department of Environmental Protection (FDEP)
on March 4 , 2015. This visit primarily focused on control technique options that were (or could be) included in the gypsum dewatering stack and cooling pond management plan proposed in subpart AA.

PARTICIPANTS

Tina Ndoh

– EPA Brandon Long

– ERG George Sharrock

– FDEP Syed Arif

– FDEP

- DARM
Jeff Koerner

– FDEP

- DARM Quaid Noor

– FDEP

- SWD
Jason Waters

– EPC HC

TOPICS OF DISCUSSION

The EPA and FDEP discussed various aspects of the gypsum dewatering stack and cooling pond management plan proposed in subpart AA. Specifically, t he following items applicable to the management plan were examined :

 Enforcement options for the management plan : FDEP offered the following question for
the EPA to consider: h ow would enforcement officials interpret the control techniques and determine if facilities were complying? They suggested that the management plan
either contain more specificity for each control technique opti on, or include a review and approval process where the specifics would be determined between the facility and state/federal agency

. The FDEP also requested clarity on if and how the control technique option s and management plan would be implemented into th eir Title V permit. It was2

noted that f

acilities may need the ability to incorporate work practice requirements into
their permit for compliance

.

 Consistency of definitions between Federal and State regulations : FDEP suggested that

t he EPA may c onsider the use of “ gypsum dewatering stack system” versus simply

“ gypsum dewatering stack

, ” because FDEP rules reference the “ gypsum dewatering stack system.”

 Discharge pipes : Submerging the discharge pipe may be possible for certain pipes. It is probably not practi cal for the gypsum slurry discharge pipe from a compliance perspective (partly because the pipe moves). The EPA may want the control technique language to focus on the hot water discharge pipe from the plant.

 Slaked lime : FDEP suggested that the EPA consider using language that stated slaked lime does not need to be applied to the entire gypsum dewatering stack.

 Soil caps and vegetation on side slopes : FDEP suggested t he EPA allow flexibility with “50 feet” language ( remove it ) and when soil and vegetation could be applied. FDEP noted that g rassing does not occur at certain or consistent intervals, there is no set
method. FDEP also explained that facilities define “top” as essentially at bench heights and not necessarily the ultimate height, so us e of distances from “top” would require
clarification

.

 Rim ditch : FDEP requested clarification on how facilities would show they are minimizing the surface area by using the rim ditch technique

. Would they need to show
that area is minimized for each cell? FDEP suggested emphasizing “cells” for
minimization. An option discussed was that facilities m ay want to compare the surface
area from using the rim ditch technique to the surface area that wou ld exist if another technique were used (i.e., area if only a single outer dike existed).

 G ypsum D ewatering S tack Ratio Limit: F DEP suggested the ratio of phosphoric acid manufacturing capacity versus gypsum dewatering stack area could be used as a control technique option, rather than requiring facilities to meet the limit.

 Cooling pond area minimization : FDEP and the EPA discuss ed an option of allowing facilities to develop a plan that evaluates their cooling pond area to show it is appropriate for the operations and conditions at their facilities. Emergency ponds would be allowed,
but the evaluation would need to discuss and consider this. The evaluation w ould need to show the cooling pond area is necessary, considering allowances for hurricanes and
excessive rain , and that excessive ponds are not used. If the cooling pond area is too large , this control technique would need to requir e facilities to create a plan to reduce the

area.