Title: Water Management Plan
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Permanent Link: http://ufdc.ufl.edu/WL00004105/00001
 Material Information
Title: Water Management Plan
Physical Description: Book
Language: English
 Subjects
Spatial Coverage: North America -- United States of America -- Florida
 Notes
Abstract: Jake Varn Collection - Water Management Plan (JDV Box 54)
General Note: Box 17, Folder 3 ( WaterTransbasin Transfers - 1970s ), Item 6
Funding: Digitized by the Legal Technology Institute in the Levin College of Law at the University of Florida.
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Bibliographic ID: WL00004105
Volume ID: VID00001
Source Institution: Levin College of Law, University of Florida
Holding Location: Levin College of Law, University of Florida
Rights Management: All rights reserved by the source institution and holding location.

Full Text






6.0 WATER MANAGEMENT PLAN

The consumptive use of water .. means any use of water which reduces the

supply from which it is withdrawn or diverted." (16J-0.02 (4)). A use of

water may be considered non-consumptive if it is in some manner returned to the

supply. This chapter details the proposed development of surface and ground-

water supplies and the consumptive and non-consumptive loss of water from the

recirculating process-water system.


6.1 MAKE-UP WATER REQUIREMENTS AND SOURCES

A preliminary process-engineering design combined with an extensive geologic

investigation of the ore body has resulted in the best estimate now available

as to make-up water requirements of the proposed mine and beneficiation plant.


The processing and transport of the phosphate ore will require 12,086 gpm of

make-up water. Water quality considerations in the amine flotation process

require that at least 7,292 gpm of the make-up water be of a higher quality

than water available in streams. This higher quality water must be derived

from the Lower Unit of the Floridan Aquifer.


The transport of the slurried ore and waste tailings will require the use of

large water-lubricated centrifugal pumps. These pumps will require an average

total use of 300 gpm. Where clean water is not available from the process

water system, water from the Upper Unit of the Floridan Aquifer will be

obtained from low capacity wells drilled near the pumps. The remaining 4,494

gpm of water needs may come from surface-water sources.


* ..c- I .


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6.1.1 SURFACE-WATER USE

A proposed off-stream storage basin on Brushy Creek can provide an average

of 3,812 gpm of make-up water. The water collected in this manner will be

pumped from the basin to the mining area to make a slurry of the mined

ore.


6.1.1.1 BRUSHY CREEK STORAGE BASIN

Mississippi Chemical Corporation proposes that surface water be diverted from

Brushy Creek to an off-channel storage basin which can be in operation by the

fourth year of mining. The proposed basin will cover approximately 200 acres,

have approximately 9,500 acre-feet capacity, be 50 feet deep below the stream

channel and have 2:1 slopes on the sides. Figure 6-1 is a schematic diagram of

the proposed basin layout.


A low-water control weir, which consists of three bays each 7.75 feet long, can

be installed in Brushy Creek in the NW, SW, Section 25, Township 34 South,

Range 23 East. Elevations of the side weir boards will be set 0.25 and 0.50

feet above the center board. The entire control structure will be inundated by

natural flow when water is about 3 feet deep in the natural channel. Diversion

weirs, consisting of six bays, each 7.75 feet long, will be set with the first

bay 0.25 feet higher than the lowest channel bay, such that 3.25 cubic feet per

second will bypass the diversion before any streamflow is removed. The second

and third bays will be set 0.25 feet higher than the first bay; the fourth bay,

0.50 feet higher; and the fifth and sixth bays, 0.75 feet higher.


6.1.2 GROUND-WATER USE

Of the 12,093 gpm of total water required, process water-quality considerations


a6-2


-- s -9--- -----~------










Schematic of Proposed Brushy Creek
Storage Basin


proepud by:
P.E. LaMoreaux & Associates Inc.


See


Stream Gaging
Station r


Storage Basin Location


IN-CHANNEL WEIR


O~ 1


Detail "B"
SIDE-CHANNEL WEIR
SI I
I 2


Figure 6-1


______ _


1^,










among other considerations make necessary the withdrawal of at least 7,592

gpm from all ground-water sources. However, since surface-water sources can

only provide an average of 3,812 gpm of make-up water, an average withdrawal

of 8,281 gpm from all ground-water sources is necessary to meet all water

requirements.


6.1.2.1 PROPOSED WELL FIELDS

It is proposed that the process make-up water be withdrawn from the Lower Unit

of the Floridan Aquifer. The production well field will consist of five deep

wells including test well MCLF-1, which is already installed and has a capacity

of approximately 3,500 gpm and four additional wells, each having production

capacities of approximately 5,000 gpm (locations shown in Figure 6-2). Each

of the additional wells will be constructed as shown in Figure 6-3. The wells

will be constructed with a 24-inch casing penetrating the top of the Suwannee

Limestone and completed with an 18-inch diameter open hole to a depth of approx-

imately 1,250 feet. Each well will be provided with a meter to measure the

amount of water pumped. The production well field, as presently designed, will

have a maximum capacity of approximately 23,500 gpm (33.84 mgd) with the ability

to provide the entire process make-up water requirements when necessary. The

average daily withdrawal from the well field will be 7,974 (11.48 mgd). After

the well field is installed and tested, aquifer-simulation techniques can be

used to develop pumping schedules that will minimize drawdown.


In addition to the proposed production well field, temporary small diameter wells

completed in the Upper Floridan Aquifer will be constructed to provide seal water

for centrifugal pumps on the matrix lines and the tailings lines. The mine will


6-4


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II


0
c
0


*mJ
O2


Figure 6-2











Schematic of 24" Well Designed to Yield Approximately
5000 G.RM. on a Continuous Basis


FLOW MAfEL


AI D/SCI2CZ



36"OD CAS/NG

34" HOL E

APPeOX. 220 BAOS CEMHEA/T ...


29"HOLE ----
APPROX. SGQO BA CEAINT-
CerNTfRAL Z/ZE/ TO MA/N/TA//
2" //NI/UM AUNNULUS


NOTE:
/ STEEL CA4S/A/ OR L/A/ER P/FPE
SHALL /A VE A WALL T /CAKWESS
OP N107 LESS T/IAA/ 0,775"


PR. orby
P.E. La Moreaux & Associates. Inc.


Figure 6-3









normally have six centrifugal seal water pumps which will require a total of

300 gpm under average conditions. These wells will be abandoned in accord-

ance with the SWFWMD rules and regulations, and new wells drilled frequently

as the location of the centrifugal pumps are changed. The locations of these

wells have not been determined at this time.


A single small-diameter potable-water well will provide for the domestic water

needs of the plant facility which are estimated to average 7 gpm.


6.2 NON-CONSUMPTIVE USE OF WATER

As indicated in Table 6-1, 16 percent or 2,312 gpm of the total expected water

losses are considered non-consumptive. The following discussions provide a

better understanding of these non-consumptive water losses.


6.2.1 PRODUCT-STORAGE SEEPAGE

The preliminary plant design for the proposed facility calls for an above ground

wet-rock storage area with a capacity of 800,000 tons of phosphate rock. The

wet-rock storage area insures the capability of shipping rock at uniform rates

even when the mine and beneficiation plant are not in operation.


As designed, wet rock at 16 percent moisture will be conveyed to rock storage

and stacked via an overhead conveyor. A tunnel reclaim system will transport

rock from the storage area via conveyor for shipment as wet rock or for further

processing in the drying area.


Depending upon the amount of rock in storage and shipment rates at any particular

time, wet rock could conceivably be help in storage for two months or longer.


~F


__ __..._~. 1,,1 ~ -. c-- ~ ----- ~-"s~-----I- ~y~










Table 6-1 Summary of Water Use


SOURCES OF WATER

Kind GPM Description


Surface water
Ground water production well field
Sealing water wells
Potable supply well
Matrix

Total Make-Up Requirement


3,812
7,974
300
7
2,236

14,329


Brushy Creek
Deep Well
Shallow Well
Deep Well
Entrainment


NON-CONSUMPTIVE USES


Product Storage
Waste Pebble Storage
Tailings Disposal
Tailings
Clay Disposal area
Ditch Losses

Total Non-Consumptive Use


10
20
300
925
860
197

2,312


Seepage
Seepage
Seepage
Entrainment
Seepage
Seepage


CONSUMPTIVE USE


Clay wastes
Waste pebble
Product

Sub-Total
Less matrix moisture

Total Consumptive Use


11,700
90
227

12,017
2,236

9,781


Entrainment
Entrainment
Entrainment


L;)r I --


~ ----~---- I-~-P-lu~n~--l~-~i~~a~--------










During this period of storage it is expected that the average moisture content

of the rock will decrease from 16 percent to 13 percent due directly to seepage

to the ground-water system. Most of the seepage will be recovered and

returned to the recirculating water system by means of extensive ditches

around the perimeter of the storage area. However, approximately 10 gpm of

the expected seepage will be returned to the ground-water system.


6.2.2 WASTE PEBBLE-STORAGE SEEPAGE

It is expected that over 1 million tons per year of waste or reject pebble will

be produced by the proposed facility. This waste material will be disposed of

by slurrying with water to approximately 20 percent moisture and pumping to a

disposal area. The intended disposal area will be a mine pit set aside in the

first phases of operation.


The waste pebble will eventually drain to approximately 13 percent moisture.

A major portion of the water which drains from the waste pebble will be

recovered and returned to the recirculating water system by means of

ditching in and around the disposal area. It is anticipated that approxi-

mately 20 gpm will be returned through seepage to the ground-water system.


6.2.3 TAILINGS DISPOSAL AREA SEEPAGE/ENTRAINMENT

A major waste product of the proposed facility will be sand tailings. It is

expected that over 10 million tons of sand tailings will be produced each year.

The disposal of this material is an important consideration. The process design

plans for sand tailings to be dewatered to 60 percent moisture in the plant area

and then pumped to various areas for use in reclamation or dam construction. At

dam construction sites, dewatering cyclones will be utilized to reduce the sand


6-9


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_ -- 'I ---ir -----~- ---- '--~-- r --













tailings moisture to 35 percent. The cyclone overflow (water removed from

the tailings) is returned to the plant recirculating system.


Following initial disposal, the sand tailings are expected to drain further and

reach a final moisture content of 15 percent. A major portion of the water

removed during this draining period will be recovered by ditching and returned

to the plant recirculating water system. Approximately 300 gpm will be returned

to the ground-water system through seepage.


The final moisture content of the sand tailings (15 percent) is due to entrain-

ment. Since these sands will be utilized in dam construction, developing lake

bottoms, filling mined cuts, covering clay disposal areas, these sands will be

used to create and(or) augment natural surficial sand deposits which comprise

the Water-Table Aquifer. Thus, the entrained moisture will be returned to

the ground-water system at an average rate of 925 gpm based upon an average

tailings production of 10 mtpy.


6.2.4 CLAY DISPOSAL AREA SEEPAGE

The greatest waste disposal consideration for the proposed facility will be

caused by waste clays. During the first five years of mining, approximately

1,500 acres will be converted to clay disposal areas. This acreage will be

completely surrounded by embankments 60 feet above natural ground. Approxi-

mately 860 gpm of water from these areas will be returned to the ground-water

system by controlled seepage through embankments and pond bottoms. This

estimate of seepage quantity is based upon the projected dimensions and

characteristics of the two settling areas proposed during the first five

years.
6-10










6.2.5 DITCH-LOSSES SEEPAGE

The plant recirculating water system will recycle 95,000 gpm for reuse in the

mine and beneficiation plant. To accomplish this an extensive amount of

ditching will be required. It is anticipated that 197 gpm will be returned

to the ground-water system through seepage from recirculating water ditches.

This estimate of seepage quantity is based upon the projected dimensions and

characteristics of the water return system proposed during the first five

years of mining.


6.3 CONSUMPTIVE USE OF WATER

Eighty-five percent of the total water losses are considered consumptive losses

and therefore represent consumptive use. The consumptive losses are incurred

through clay-waste entrainment, waste-pebble entrainment and entrainment in the

product as shown in Table 6-1.


6.3.1 CLAY-WASTE ENTRAINMENT

Clay-waste entrainment is the largest single consumer of process water. The

separation of the phosphate ore from the clay matrix requires large amounts

of water. The clay, which in its natural state contains 40 percent moisture,

emerges from this process containing only 3 to 4 percent solids (96 to 97

percent moisture). The result is a large volume of clay and water which must

be pumped into retention areas where the clays settle from the water and the

clear water is decanted for reuse in the beneficiation process. The clays

at 96 to 97 percent moisture will not return to the original 40 percent

moisture for a long period of time. However, a moisture content of 82 per-

cent is attainable within a reasonable time. Based upon an 82 percent final


6-11


II -










Moisture content, and a production of clay wastes of approximately 5.5 mtpy,

11,700 gpm (16.85 mgd) of water will be consumptively lost as unrecoverable

entrainment in the clay wastes.


6.3.2 WASTE-PEBBLE ENTRAINMENT

A significant portion of the pebble product does not meet present chemical

standards and cannot be refined at present economic levels. This waste pebble

has been subjected to the beneficiation process and must be hydraulically

transported to the below-ground storage area; 15 percent of the water is

entrained in the waste-pebble product.


Since this product is in storage for an anticipated future use, the entrained

water must be considered a consumptive loss over this period of time. Based

upon an average waste-pebble production of 1.3 mtpy, 90 gpm of entrained water

will be consumptively used.


6.3.3 PRODUCT LOSSES

Phosphate products may be shipped from the beneficiation facilities as dry-

phosphate or wet-phosphate rock. Storage of the wet-phosphate product in large

piles will encourage drainage of water within the piles. Part of this water

will be captured and returned to the recirculation process-water system or will

seep into the ground to be returned to the ground-water system. The wet-rock

storage pile will eventually approach an average moisture content of 13 percent.

This 13 percent moisture represents a consumptive use. Based on a product

production of 3 mtpy, and 13 percent moisture entrainment, 227 gpm of water

will be consumptively used.


F____6-12










NET CONSUMPTIVE USE


The total water losses at a production rate of 3 mtpy are 14,327 gpm. Non-

consumptive losses account for 2,312 gpm or 16 percent of the total water

losses. Total consumptive losses account for 12,017 gpm including the original

entrained moisture in the ore matrix. Deducting this original entrained

moisture which accounts for 2,236 gpm results in a net consumptive use of

9,781 gpm or 14.08 mgd.


6-13


PI











7.0 REGULATIONS CONCERNING THE CONSUMPTIVE USE OF WATER

Chapter 16J-2 of the Rules and Regulations of the Southwest Florida Water

Management District states the conditions under which a consumptive use

permit can be issued, and the conditions under which a consumptive use permit

can be denied. Each of the conditions as it relates to the impacts of the

proposed consumptive use is discussed below.


7.1 CONDITIONS FOR APPROVAL OF A CONSUMPTIVE USE PERMIT

The conditions for approval of a consumptive use permit are stated in Section

16J-2.11. Subsection (1) states that:

"the intended consumptive use:

(a) Must be a reasonable, beneficial use
(b) Must be consistent with the public interest
(c) Will not interfere with any legal use of water existing at the time
of the application."


Section 16J-0.02 (15) defines reasonable beneficial use as:

"the use of water in such quantity as is necessary for economic and
efficient utilization for a purpose and in a manner which is both
reasonable and consistent with the public interest. Subsection
373.019 (5) FS."


7.1.1 REASONABLE AND BENEFICIAL USE (Ref. 16J-2.11 (l)(a))

The proposed phosphate-mining operation will provide 3 million tons per year

of phosphate rock. Most of the phosphate rock will be processed into finished

phosphate fertilizers at plants in Mississippi for use by the Mississippi

Chemical Corporation farmer-owners. The remaining phosphate rock will be com-

mitted on a long-term basis to other phosphate consumers. Consequently, a

major portion of the product of the proposed mine will ultimately be used to

produce domestic food and fiber.


k7-1


---I --- I- "- I










At the local level, the proposed phosphate mine will provide 650-700 construc-

tion jobs for about two years while construction is underway. During sustained

operation, the proposed phosphate mine will provide 450 jobs for 31.5 years.

The annual payroll will be $6,091,000. The annual tax revenues to the State

and local governments may approach $3,400,000. Goods and services required

by the proposed mine and its employees will generate $18,675,000 to $22,850,000

in income to new or expanded support industries. Therefore, the proposed con-

sumptive use represents a sizable economic benefit to the Southeast, Florida

and Hardee County.


A major goal of the water management planning, process design and recirculating

process-water system design of the proposed phosphate mine is the efficient use

of the area's water resources. For this reason a goal of the water management

plan was to minimize the use of ground-water resources which are readily recov-

erable and greatly used, and to maximize the use of surface-water resources which

are less recoverable and little used. Chapter 6.0 details the results of this

effort.


Clarifiers were included in the process design for the maximum recovery of

water. Two such clarifiers can recover 65,000 to 75,000 gpm of clear water

from the plant discharge before it leaves the plant area, reducing evaporative

losses in the recirculation system.


The recirculating process-water system will recover 95,000 gpm of water for

reuse. This amounts to eight times the make-up water withdrawals from ground-

and surface-water sources. Therefore, through the design of the water supply,

plant design and recirculation system design, a reasonable and efficient use

of water resources is obtained.

7-2











7.1.2 CONSISTENCY WITH THE PUBLIC INTEREST (Ref. 16J-2.11 (l)(b))

In addition to the favorable economic impact of the proposed phosphate mine,

Mississippi Chemical Corporation has endeavored to determine adverse effects

and act positively to reduce or alleviate such effects through innovative and

detailed process design, mine planning, reclamation planning and water manage-

ment planning. A comprehensive environmental monitoring network will establish

base environmental conditions and give indications of any changes in conditions

as a result of mining or beneficiation.


The close working relationship between Mississippi Chemical Corporation engineers

and planners and the various regulatory agencies, combined with a proven record

of environmental concern shown by Mississippi Chemical Corporation in its other

operations, will insure that the requested consumptive use is .consistent with

public interest.


7.1.3 INTERFERENCE WITH EXISTING LEGAL USERS (Ref. 16J-2.11 (l)(c))


7.1.3.1 GROUND WATER

A water-well inventory was conducted to determine the existing use of ground

water within about two miles of the property. This inventory is discussed in

Section 3.4.4, and wells listed in Appendix 8.4 of the accompanying report,

Water-Resources Evaluation. The effects of the proposed well field are dis-

cussed in Section 7.4.2 of this report. The proposed well field will lower the

potentiometric surface an average of 1.5 to 2.0 feet in the deep wells nearest

the property. This amount of drawdown will not prevent the legal use of the

nearby wells by the owners.


~I











7.1.3.2 SURFACE WATER


The streams within one half mile of the property boundaries were inspected by

use of helicopter on August 22, 1976. No use other than for stock watering

was observed. The effects of mining on the flow of streams is discussed in

Section 4.8 and the effects of the proposed Brushy Creek Storage Basin are dis-

cussed in Section 7.4.1 of this report. The proposed phosphate-mining operation

and the proposed withdrawal of surface water will not interfere with any existing

surface-water use.


7.2 CONDITIONS FOR DENIAL OF A CONSUMPTIVE USE PERMIT

The conditions for denial of a consumptive use permit are stated in Section

16J-2.11. Subsection (2) states that the:

"issuance of a permit will be denied if the withdrawal of water:

(a) Will cause the rate of flow of a stream or other watercourse to be
lowered below the minimum rate of flow established by the Board.
(b) Will cause the level of the potentiometric surface to be lowered
below the regulatory level established by the Board.
(c) Will cause the level of the surface of water to be lowered below
the minimum level established by the Board.
(d) Will significantly induce salt water encroachment.
(e) Will cause the water table to be lowered so that the lake stages
or vegetation will be adversely and significantly affected on lands
other than those owned, leased, or otherwise controlled by the
applicant."


Section 16J-0.02 defines stream as:

"any river, creek, slough, or natural water course." (16J-0.02 (17));


other watercourse as:

any canal, ditch, or other artificial watercourse in which water
usually flows in a defined bed or channel. It is not essential that the
flowing be uniform or uninterrupted. Subsection 373.019 (13) FS."
(16J-0.02 (12));


__










minimum level as:


the level of the water table or of the potentiometric surface of
water in an aquifer or the level of surface water at which further with-
drawals would be significantly harmful to the water resources of the
area." (16J-0.02 (11));


minimum rate of flow as:

the limit at which further withdrawals from a stream or other
watercourse would be significantly harmful to the water resources or
ecology of the area." (16J-0.02 (10)); and


otherwise control as:

any contractual right, rental agreement, license, or permit from
an owner which an applicant has to exercise authority over certain
property, especially insofar as it relates to the water resources of
the property." (16J-0.02 (13)).


7.2.1 ESTABLISHMENT OF MINIMUM RATES OF FLOWS AND LEVELS

The following methods govern the establishment of minimum rates of flows and

levels:

16J-0.15 Minimum Rates of Flows and Levels.
(1) In establishing minimum rates of flows and levels and regulatory
levels, the Board shall use the best information and method available
and will consider the protection of existing, as well as future con-
sumptive uses of water so as to promote the conservation, development
and proper utilization of water while preventing damage from floods,
soil erosion and excessive drainage. When deemed appropriate, a
schedule of rates of flows and levels will be established to reflect
seasonal or cyclic variations. The Board will also consider, and at
its discretion may provide for, the protection of nonconsumptive uses,
including navigation, recreation and the preservation of natural
resources, fish and wildlife.
(2) Unless otherwise deemed appropriate by the Board, the minimum
rates of flow at a given point on a stream or other watercourse shall
be established by the Board for each month, January through December.
Minimum rates of flow shall be established as follows. For each month,
the five (5) lowest monthly mean discharges for the preceding twenty
(20) years shall be averaged. Minimum rates of flow values for the
four (4) wettest months and ninety percent (90%) of these values for
the remaining eight (8) months. The determination shall be based on
available data, or in the absence of such data, it shall be established
by reasonable calculations approved by the Board.


i-re










(3) Unless otherwise deemed appropriate by the Board, the minimum
levels of water of a given lake or other impoundment or at a given
point on a stream or other watercourse shall be established by the
Board and shall be one foot (1') below the average of the five (5)
lowest water levels in each calendar year (provided no two (2) levels
shall be taken from the same calendar month) for the preceding ten
(10) years. The determination shall be based on available data or in
the absence of such data, it shall be established by reasonable calcu-
lations approved by the Board.
(4) Unless otherwise deemed appropriate by the Board, the minimum
level of the water table at a given point shall be established by the
Board and shall be three feet (3') below the average of the five (5)
lowest levels in each calendar year (provided no two (2) levels shall
be taken from the same calendar month) for the preceding ten (10)
years. The determination shall be based on available data or in the
absence of such data, it shall be established by reasonable calcula-
tions approved by the Board.
(5) Unless otherwise deemed appropriate by the Board, a regulatory
level for a confined aquifer at a given point shall be established
generally to limit the rate of movement of water from the water table
at the boundary of the land owned, leased, or otherwise controlled by
an applicant for a consumptive use permit or at the boundary of an
equivalent area based on the configuration of the cone of depression
caused by the proposed location and operation of the well or wells.
(a) Such regulatory level shall be determined by taking the
minimum level of the water table plus three feet (3'), or such other
adjustment as deemed appropriate by the Board, and subtracting the
head difference required to pass the water crop from the water table
to the confined aquifer. Such head difference is the water crop
divided by the leakance coefficient of the confining bed. The water
crop, in the absence of data to the contrary is 0.0229568 gallons per
day per square foot.
(b) The elevation of the potentiometric surface at such point
shall be measured cumulatively throughout the production year. At no
time shall the cumulative weekly average elevation be lower than the
regulatory level and at no time shall the weekly average elevations
of the potentiometric surface of the Floridan Aquifer be more than
five feet (5') below the regulatory level.
General Authority 373.044, 373.113, 373.149, 373.171FS.
Law Implemented 373.042, 373.339FS. History--Readopted 10-5-74,
Amended 12-31-74.


7.2.2 EFFECTS ON MINIMUM RATE OF FLOW (Ref. 16J-2.11 (2)(a))

During three phases of mining certain parcels of land are cut off from natural

drainage. At these times streamflow will be reduced. The effects of mining

will vary from year to year with the amount of rainfall; therefore, long-term


7-6


- --Y- -I1P~-- I ----- --I IIII -- -- -r-~--











annual flows have been evaluated. During the active mining phase all water

falling in open pits will be occluded from streamflow. When a parcel is used

for clay storage most of the flow is retained in a closed system. When the

system is full, excess clarified pondage is returned to streams. During

reclamation of clay storage areas, when clay is no longer being added to the

area, almost all runoff is returned to streamflow. Sand tailings areas are

also separated from natural drainage. Only excess flow, estimated to be 10

percent of the total that falls on the sand tailings and clay pond areas, is

returned to streams.


Based on simulated monthly streamflow records at Stations SG-5 (Oak Creek

outflow) and SG-I (Brushy Creek outflow), regulatory minimum rates of flow

were determined using the methodology explained in Section 16J-0.15 (2).

The average monthly regulatory minimum rates of flow at the Oak and Brushy

Creek outflows are shown in Tables 7-1 and 7-2. These tables show that Oak

Creek, at Station SG-5, where the simulated average annual flow under natural

conditions is 11 cfs, the average annual flow during mining will be approxi-

mately 9.8 cfs. For Brushy Creek, at Station SG-1, where the simulated average

annual flow under natural conditions is 30.0 cfs, the average annual flow

during mining will be approximately 28.0 cfs or 18.9 cfs if the effects of the

proposed diversion are considered. During the active mining phase, streamflows

at the outflow of Oak and Brushy Creeks will not be reduced below the minimum

rates of flow that may be established by the Board. Downstream, at Station

No. 02297310, Horse Creek near Arcadia, Fla., the effects caused by mining

and withdrawals are shown in Table 7-3.


I~C-l










Table 7-1 Effect of Mining on Oak Creek at SG-5


1 Regulatory Minimum
Average Flow Average Flow Rate of Flow
cfs cfs cfs

0 16.8 14.6 .84
N 3.8 3.3 .005
D 2.1 1.83 .005
J .47 .41 0
F 5.3 4.6 .030
M 7.8 6.7 .017
A 3.3 2.8 0
M 1.4 1.2 0
J 9.1 7.9 .077
J 18.3 15.9 1.86
A 23.5 20.4 5.83
S 28.4 24.7 5.29

YR 11 9.8


As affected by average mining conditions.




Table 7-2 Effect of Mining on Brushy Creek at SG-I

1 2 Regulatory Minimum
Average Flow Average Flow Average Flow Rate of Flow
cfs cfs cfs cfs

0 47.2 44.6 31 2.5
N 11.1 10.5 8.0 .22
D 6.5 6.1 5.0 .21
J 13.5 12.8 8.6 .20
F 15.4 14.5 10.2 .45
M 22.1 20.9 13.2 .19
A 9.6 9.0 7.3 .014
M 4.2 4.0 2.9 .002
J 25.4 24.0 14.5 .48
J 51.3 48.4 29.0 5.58
A 65.5 61.8 42.0 16.4
S 79.2 74.8 52.0 15.0

YR 30.0 28.0 18.9


As affected by average mining condition.
2As affected by average mining condition and proposed diversion.


S7-8










Table 7-3


Effects of Mining and Diversion on Station
Creek near Arcadia, Floridal


02297310, Horse


Avg. Flow Reduction in Reduction in Total
25-Year Streamflow Due Streamflow Due Reduction of
Long Term to Mining to Withdrawal Streamflow

cfs cfs Percent cfs Percent Percent

0 330 2.5 0.76 13.8 4.2 5
N 82.6 .6 .76 2.5 3.0 4
D 50.3 .4 .76 1.1 2.2 3
J 48.2 .7 .76 4.2 4.3 5
F 111 .8 .76 4.2 3.8 5
M 157 1.2 .76 7.7 4.9 6
A 20.1 .5 .76 2.7 3.9 5
M 30.9 .2 .76 1.1 3.6 4
J 179 1.4 .76 9.5 5.3 6
J 358 2.7 .76 19.6 5.5 6
A 454 3.4 .76 19.7 4.3 5
S 549 4.1 .76 22.7 4.1 5

YR 209 1.6 .76 9.1 4.4 5


1Drainage area is 218 sq. mi.



7.2.3 LOWERING OF THE POTENTIOMETRIC SURFACE BELOW THE REGULATORY LEVEL
(Ref. 16J-2.11 (2)(b))

No regulatory level for the potentiometric surface has been established by the

SWFWMD Board. Chapter 16J-2.11 (4)(e) prohibits the lowering of the potentio-

metric surface below mean sea level, a regulation to which Mississippi Chemical

Corporation will comply.


7.2.4 LOWERING OF THE SURFACE OF WATER BELOW THE MINIMUM LEVEL
(Ref. 16J-2.11 (2)(c))

No minimum level for the surface of water has been established by the Board

for this area.










7.2.5 EFFECTS OF WITHDRAWALS ON THE SALT-WATER INTERFACE
(Ref. 16J-2.11 (2)(d)

Using the September, 1975, potentiometric surface of 45 feet above mean sea

level at the proposed plant site, the salt water-fresh water interface there

was calculated to be about 1,800 feet below sea level. If an impermeable zone

or strata exists between the part of the aquifer being pumped and the salt

water-fresh water interface, salt water cannot readily move upward. The trans-

missivity of the Lake City Limestone underlying the Floridan Aquifer, some four

miles north of the plant site, at the C. F. Industries plant site, has been

calculated to be 1,400 gpd/ft. Data from a deep test well at the plant site

shows an evaporite strata beginning at a depth of about 1,600 feet. The low

transmissivity of the Lake City Limestone and the presence of an evaporite strata

indicate the existence of such an impermeable zone. Under these conditions,

movement of the interface would be sufficiently retarded as to be of little or

no consequence in this area of Hardee County. Should this impermeable zone not

be continuous, salt-water encroachment would not occur for the following reasons:

The theoretical minimum depth of the interface, using the Ghyben-Herzberg principle,

is 1,800 feet below sea level. With this condition, considerable drawdowns could

be imposed on the system before salt-water encroachment would be a problem. The

transmissivity of the Floridan Aquifer is extremely high in Hardee County.

Because of this, drawdowns from proposed production wells would be small. As

an additional safeguard against salt-water encroachment, water removed from the

Floridan Aquifer can be chemically monitored to detect any significant increase

in chlorides.


7-10










7.2.6 EFFECTS ON LAKES OR VEGETATION (Ref. 16J-2.11 (2)(e))

The distance-drawdown relationship discussed in Section 7.4.3 shows the average

dewatering with distance that can be expected. On the average, the effects are

not pronounced and no adverse effects on lake levels or vegetation are antic-

ipated.


7.3 THE WATER CROP

The SWFWMD has determined a regulatory limit on the amount of water that may

be consumptively used by the permitted as stated below:

"Issuance of a permit will be denied if the amount of water consumptively
used will exceed the water crop of lands owned, leased, or otherwise
controlled by the applicant. (Except where determined otherwise, the
water crop (precipitation less evapotranspiration) throughout the District
will be assumed to be three hundred sixty-five thousand (365,000) gallons
per year per acre.)" 16J-2.11 (3).


Mississippi Chemical Corporation owns or controls 14,850 acres of land. Based

on a water crop of 365,000 gallons per year per acre (gpy/ac), the total avail-

able water crop is 542,025,000 gpy/ac or 14.85 mgd. As determined in Section 6.4,

the average daily consumptive use of water is 14.08 mgd which is less than the

allowable water crop.


7.4 EFFECTS OF WITHDRAWAL OF WATER ON SURROUNDING PROPERTIES

The SWFWMD has established the following criteria to limit the effects of

withdrawals of water on surrounding lands:

16J-2.11 "(4) the withdrawal of water:

(a) From a stream or other watercourse must not reduce the rate of flow
by more than five percent (5%) at the time and point of withdrawal.
(b) Must not cause the level of the potentiometric surface under lands
not owned, leased, or otherwise controlled by the applicant to be
lowered more than five feet (5').
(c) Must not cause the level of the water table under lands not owned,
leased, or otherwise controlled by the applicant to be lowered more
than three feet (3').


7-11


I --'I










(d) Must not cause the level of the surface of water in any lake or
other impoundment to be lowered more than one foot (1') unless the
lake or impoundment is wholly owned, leased, or otherwise controlled
by the applicant.
(e) Must not cause the potentiometric surface to be lowered below sea
level."


7.4.1 EFFECTS OF PROPOSED WITHDRAWAL ON STREAMS (Ref. 16J-2.11 (4)(a))

Ratings were prepared for streamflows and diversion flows and a diversion of

simulated flow was computed. This was done using simulated daily discharges

transferred from Station No. 02297310 (Horse Creek near Arcadia, Fla.). The

simulated flows were adjusted to reflect changes in water availability

resulting from mining operations in the basin. Table 7-4 shows the simulated

monthly and yearly average flows, in cfs, withdrawn from the storage basin for

mine use. Table 7-5 shows the flows released downstream in order to maintain

required downstream flows. Table 7-6 shows calculated average monthly and

yearly water storage in the basin in cfs-days. Table 7-4 shows the 25-year

average diversion to be 8.49 cfs (5.49 mgd), which is 85 percent of the surface

water needed for the plant. This study shows that the reservoir would be full

about 6 times in a 25-year period and it would be empty 12 times. The average

storage over 25 years would be 1,908 cfs-days or 40 percent of the reservoir

capacity. During times when the reservoir is at a minimum level and surface

water is not available for process make-up water, the required make-up water

will be withdrawn from the proposed well field.


Figure 7-1 is a graph showing relation of flow diverted and passed downstream

to total flow available in Brushy Creek during the period of mining. Figure 7-2

is a hydrograph of a simulated dry year (1971) showing the effect of diversion.

Figure 7-3 is a hydrograph of a wet year (1960) showing the effect of diversion.


7-12


I ~~WP*


i --I-1 ---~-PI*YIPP~~--'Y'--9~LBi~L~Pi~,hPC~i ~~---iiB---~-Pl/sl~-I
















Table 7-4 Simulated Monthly and Yearly Average Withdrawals, in cfs,
From the Brushy Creek Storage Basin








Mc-CF' 30C oPLANT, PHX. 9500. A- 0. PL- 4465.EtRR .000 L2...*** DOH .250


AVERAGE DISCHARGE IN CpS



OCT NOV DEC JAN FsB MAR APR MAY JUN JUL AUG SEP YEARLY


1950 .00 .03 3.44 9.95

1951 9.95 9.95 9.95 2.8' .01 .OP 7.00 .10 .00 4.85 9.95 9.95 5.41
1952 9. 95 5 9.9 99 995 9.95 9.69 1.20 .00 .00 .94 9.95 8.15 6.64
1953 ..95 59. .9 9.95 9. 995 95 995 995 995 9.9 5 9.95 9.95 .95 9.95 9.95
1o54 9.95 99. 9 .95 9.9 95 9.95 .5 .95 9.95 9.95 9.95 9.95 9.95 9.95
1955 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95

1956 9.95 9.95 9.95 9.95 9.95 9.95 9.95 .97 .00 .00 1.96 9.95 6.85
1957 9.95 2.17 .0" .01 .14 7.32 2.05 5.5p 9.95 9.95 9.95 9.95 5.62
1951 9.95 99.9 9.95 9.95 9.95 9.95 9. 95 9.95 9.95 9.95 9.95 9.95
1959 9.95 9.95 .9 9.95 9.95 9.95 9 .95 9.95 9.95 9.95 9.95 9.95 9.95
1960 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95

1961 9.95 9 9.95 9.95 .95 9.95 9.9 9.95 5 9.95 999. 9.95 9.95 9.95
1962 9.95 9.95 9.91 9.95 9.95 9*95 9.95 4.22 4.94 9.95 9.95 9.95 9.05
1963 9.95 9.95 V.9% 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95
1964 9.95 995 9.9 995 9 9.5 959.9 9.95 95 9.9 7.21 .48 5.30 9.95 8.53
1965 a.76 .00 .0 .3 .30 2.65 .00 .00 4.67 9.95 9.95 9.95 3.86

1966 9.95 9.95 9.;4 9.9q 0.95 9.9< 9.95 9.95 9.95 9.95 9.95 9.95 9.95
1967 9.95 9.95 9.9' .95 9 9.95 9.95 9.95 9.9. 9.95 7.39 9.95 9.95 9.7
1968 9.95 9.95 9.95 9.95 9.95 9.95 1.66 .00 8.92 9.95 9.95 9.95 8.34
1969 9.95 9.93 9.9 9.9 5 9 9.95 9.95 9.95 9.95 9.95 9.95 .95
1970 9.95 9.95 9 9.95 9.95 9.95 9.95 9.95 9.95 9.9 995 9.95 9.95

1971 9.95 9.95 9.99 9.95 9.95 9.95 9.95 9.95 9.95 9.95 9.95. 9.95 9.95
1072 9.95 9.95 .9 0.95 9.95 .95 9.95 9.09 3.98 5.27 3.99 9.95 8.49
1973 9.95 9.95 5.11 5.el 9.95 9.95 9.95 5.78 .02 4.63 9.95 9.95 7.55
1974 9.95 6.29 .0" .0 .CC .00 .0 00 1.39 9.95 9.95 9.95 3.9#
1975 9.95 9.95 9.9' 9.95 0.95 9.95 9.95 9.95 4.35 4.7? 7.67 9.95 8.86



MONTHLY STATISTICS IN CFS


OCT NOV DEC JAN FEb MAR APR AY JUt. JUL AUG SEP YEARLY


AVG6 9.90 9.09 0.5A b.30 8.36 b.75 8.04 7.00 6.99 7.60 8.90 9.88 8.49

STo- .24 2.54 3.37 3.52 3.71 3.04 3.67 4.21 3.97 3.65 2.36 .35 1.98

MAX- 9.95 9.95 9.95 9.95 9*95 9.95 9.95 9.95 995 9.95 9.95 9*95 9.95

I.N- 8.76 .00 .0o .00 .00 .0( .00 .00 .00 .0G 1.96 8.15 3.86


wNRa 25. 25. 25. 25. 25. 25. 25. 25. 25. 26. 26. 26. 25.


7-13


I~Igl -


-----~















Table 7-5 Simulated Monthly and Yearly Average Flows, in cfs,
Released Downstream on Brushy Creek







-(-CFr A 30C OSTREA, P'x 9500. Wu 3. PL1 4465.ERRl .000 L2**.* 0* O 250


AVERAGE DISCHARGE IN CFS



OC1 knV DEC JAA FEB MAq APR MAY JUN JUL A J SEP EARLY


1950 .1*4 1.6 7.43 23.10

1951 9.77 2.00 1.6' .79 2.03 .2' 9.82 1.02 .02 16.70 t1.80 6.11 5.44
1952 20.3n 2.77 1.11 .57 3.91 5.8 2.61 .06 .20 4.00 14.40 12.00 5.68
1953 41.20 11.0n 5.7' 9.22 12.37 1.50 4.13 .19 24.90 17.60 31.70 93.10 21.20
1956 8.70 29.60 24.4" 10.9' 3.3C 3.27 6.25 9.35 11.00 19.40 12.50 15.80 19.70*
1955 10.50 4**) 4.6 2.92 5.32 1.04 1.03 .05 .12 .57 15.70 26.50 6.05

19576.76 .19 .1 .1 .te .1" .01 .11 .00 .08 3.96 15.10 2.09
1957 12.90 1.00 .01 .;6 .70 11.10 6.41 13.90 8.46 16.50 23.90 25.40 10.10
1958 22.5" 1.32 4.0' >5.4 16.30 29.0C 16.00 8.75 3.11 16.40 10.80 3.09 13.1C
1959 2.21 5.06 4.1n 6.7" 3.94 25.3n 8.11 1.51 22.00 38.30 99.00 145.00 30.20
1960 37.00 5.97 2.99 1.97 10.30 14.40 6.40 2.25 2.75 28.10 127.00 153.00 32.70
1061 55.60 7.14 1.3' 3.62 9.3C 3.2' 2.89 .13 .18 8.30 14.00 12.40 9.91
1962 .37 .06 .U' .15 .11 .22 2.65 .03 9.23 12.90 17.60 45.40 7.41
1963 9.89 4.3p 1.1' 1.2' 11.Uc 10.90 .26 .21 2.60 8.63 16.20 19.30 7.13
1964 7.11 8.65 4.5' 11.9( 16.00 9.5P 6.41 .80 .72 2.97 9.24 16.10 7.79
1965 1.6 .24 .2' .31 1.01 5.67 .26 .30 7.95 34.10 29.40 6.84 7.41

19e6 20.20 2.90 1.37 5.30 16.3C 7.63 2.7P .64 22.20 12.70 16.40 12.10 10.00
1967 14.50 *.9 .21 .35 1.54 .61 .01 .00 7.42 10.40 30.80 16.00 6.95
1968 10.30 .6 1.1* .6b .30 .64 0 .56 21.90 51.10 12.60 23.20 10.30
1969 .74 10. 1.7' 4.09 2.63 17.5" 3.71 .30 17.50 13.30 19.20 19.50 9.94
1970 30.90 11.10 7.2r 13.70 6.71 19.8n 8.04 .93 12.60 11.10 15.30 16.50 12.90

1971 7.7T ..5 .2' .21 1.94 .34 .02 .00 .60 3.99 10.40 19.70 3.85
1972 16.10 7.56 6.01 1.00 8.03 1.7' 3.84 .76 8.23 4.9f 12.20 16.80 7.42
1973 5.07 1.9o 5.97 17.1" 14.70 5.2' 9.17 .34 .49 8.57 17.50 16.50 8.52
1974 4. .26 .1 .1 .C 22 .03 .0* .0" 8.1 29.20 27.40 8.67 6.67
1075 .o1 .07 .47 .17 .1 .0 .0" .00 .4P 7.74 12.30 19.30 3.47



JOINTLY STAYISIICss I CFS


0CI fMV DEC JAN FEB MA I APR MAY JUN JUL AUG SEP YEARLY


AVg. 17.77 4.94 3.37 4.7 5.96 7.00 4.C3 1.6p 7.42 14.60 23.92 30.23 10.64

STYD 20.16 6.44 S.O? 6.54 5.70 8.36 4.*C 3.53 8.16 12.5 27.43 38.85 7.65

xMxA 88.7' 29.60 24.4" 25.40 16.30 29.00 16.00 13.90 24.90 51.10 127.00 153.00 32.70

"lZh .37 .06 .06 .09 .10 .01 .05 .00 .00 .08 3.96 3.09 2.09


kYR- 25. 25. 25. 25. 25. 25. 25. 25. 26. 26. 26. 26. 25.


7--14


IPI


A.." "- -. -- '


















Table 7-6 Simulated Monthly and Yearly Average Storage, in cfs, in
the Brushy Creek Storage Basin





MC-CF A 2 30C QPOND, PMX. 950C. W- 0. PLa 4465.ERR- .000 L2**** 60H .250


AVERAGE DISCHARGE IN CFS


OCT 4OV DEC JAN FE6 MAR APR 4AY JUN JUL AUG SEP YEARLY

1950 .00 .00 .00 743.00

1951 789.00 588.00 259.0 12.50 .00 .00 21.33 .00 .00 153.00 893.00 696.00 286.00
1952 1551.00 1366.00 1048.00 713.00 395.00 104.00 .75 .00 .00 .00 25.60 17.00 436.00
1953 908.00 2389.00 2372.0' 2150.00 2085.00 lo&8.0n 1588.00 1301.00 1475.00 2202.00 2928.00 4458.00 2142.00
1954 47870 07. .00 4772.0' 465.00 4455.00 4145.00 3868.00 1663.00 !586.00 3539.00 4076.00 4090.00 4194.00
1955 4231.00 3957.00 3651.00 33?6.00 3035.00 2734.00 2405.00 2076.00 1747.00 1418.00 1291.00 2045.00 2659.00

1956 2154.00 1829.00 1500.0" 1166.0n 842.00 518.00 189.00 1.08 .00 .00 .09 58.60 689.00
1957 141.00 6.48 .On .00 .00 26.40 .00 157.00 251.00 224.00 927.00 1577.00 277.00
1958 2819.00 2688.00 2365.0" 2510.00 32?2.00 3923.00 4565.00 4474.00 4207.00 4138.00 4205.00 3968.00 3595.00
1959 3647.00 3390.00 3089.0" 2824.00 2527.00 2716.00 3326.00 3021.00 3073.00 4290.00 4789.00 4789.00 3462.00
1960 4783.00 4668.00 4346.0" 4012.00 3806.00 3727.00 3710.00 3461.Q003137.00 3106.00 4789.00 4789.00 4028.00
1961 4786.00 4692.00 4375.00 4045.00 3844.00 3621.00 3319.00 2990.00 2661.00 2363.00.2262.00 2510.00 3454.00
1962 2242.00 1913.00 1584.0" 1250.09 931.00 613.00 294.00 27.80 15.90 114.00 91.40 1260.00 861.00
1963 3141.00 2858.00 2538.0" 2273.00 1944.00 2137.0C 1855.00 1525.00 1200.00 966.00 962.00 1096.00 1870.00
1964 1389.00 1177.00 973.0" 777.00 873.00 818.00 711.00 396.00 80.50 .00 33.60 220.00 623.00
1965 125.00 .00 .0" .00 .00 2.44 .00 .00 2.32 621.00 2527.00 2734.00 503.00

1966 3109.00 2989.00 2661.0n 2319.00 2370.00 2486.01 2174.00 1847.00 1862.00 2245.00 2335.00 2400.00 2402.00
1967 2480.00 2342.00 2012.0" 1678.00 1360.00 1041.00 712.00 383.00 107.00 28.60 644.00 1580.00 1196,00
1968 1822.00 1527.00 1198.0" 863.00 540.00 216.00 3.61 .00 266.00 2377.00 3873.00 4321.00 1421.00
1969 4492.00 4444.00 4218.0n 39C2.00 3595.00 3594.00 3702.00 3375.00 3312.00 3889.00 4055.00 4340.00 3911.00
1970 4754.00 4725.00 4482.0" 4445.00 4287.00 4249.00 4695.00 4379.00 4215.00 4116.00 4033.00 4312.00 4391.00

1971 4345.00 4038.00 3709.0" 3374.00 3056.00 2738.00 2409.00 2080.00 1151.00 1424.00 1111.00 1350.00 2620.00
1972 1702.00 1797.00 1602.01 12C9.00 10!8.00 754.00 458.00 135.00 36.10 37.30 35.80 717.00 800.00
1973 553.00 237.00 10.8" U6.90 673.00 402.00 301.00 52.90 .00 11.60 256.00 408.00 253.00
1974 359.00 60.90 .0" .03 .00 .00 .00 .00 40.10 1654.00 2522.00 2874.00 630.00
1975 2591.00 2262.00 1933.00 1598.00 1280.00 962.00 632.00 303.00 28.60 .76 11.20 236.00 986.00



PONTNLY STATISTICS IN CFS

OCT NOV DEC JAN FEB MAR APR NAY JUN JUL AUG SEP EARLY


AVG* 2548.24 25424.66 2187.9 1971.14 1848:72 1740.19 1637.55 1425.91 1322.14 1556.69 1949.83 2214.95 1907.56

STO- 1603.36 1595.01 1568.4' 1525.48 1475.10 1522.60 1638.89 1577.48 1518.14 1561.08 1718.18 1675.19 1440.18

MAX- 4787.00 4725.00 4772.0n 4680.00 4455.00 4249.00 4695.00 4474.00 4215.00 4290.00 4789.00 4789.00 4391.00

MINm 125.00 .00 .0" .00 .00 .00 .00 .00 .00 .00 .09 17.00 253.00

NRr 25. 25. 25. 25. 25. 25. 25. 25. 25. 25. 25. 26. 25.


7-15










The overall effect is to withdraw water during times of excess flow up to a

maximum of 46 percent of the total flow.


7.4.2 EFFECTS OF WELL-FIELD PUMPING ON GROUND-WATER RESOURCES
(Ref. 16J-2.11 (4)(b))

The results obtained from the extensive aquifer-testing program at the plant

site provide the means of determining the hydraulic characteristics of the

aquifer in the vicinity of the test. The response of the Floridan Aquifer

to withdrawals can be determined by several methods that solve differential

equations. These computations can be made for any withdrawal, from any number

of wells, over any given time under many different hydrologic conditions.


7.4.2.1 EFFECT ON POTENTIOMETRIC SURFACE AT PROPERTY BOUNDARY
(Ref. 16J-2.11 (4)(c))

Application of the Trescott model to determine the effects of -pumping from the

proposed well field required that a map showing drawdown with distance be made

for the average daily rate of pumping over the life of the mine.


A grid measuring 25 miles on each side of 50 by 54 nodes was laid out around

the proposed well field. The five wells comprising the proposed well field

were located approximately in the center of the grid. A constant-head boundary

was placed around the grid to simulate a semi-infinite aquifer. The transmis-

sivity of the Floridan Aquifer at the proposed well field was assumed to be

1,200,000 gpd/ft.


Because no leakance was observed through the upper confining bed during the

pumping test at the proposed plant site, the area of simulation was made large

enough to include data on transmissivity and leakance from other pumping tests


7-16


. -~--.


------- I














Relations of Flow Diverted and Passed Downstream to Total Flow

Available in Brushy Creek During Period of Mining


100 II






C
75 -
E



0


S 50 -
0



IoA

Pro posed Flow to
25 3.25 fs \Diversion Structure C storage -
O Basin





r Flow Downstream

05 1 __
! 0 25 50 75 100 125 150
c Flow Available in Brushy Creek in cfs

Prepared by:
P.E. LaMoreaux & Associates. Inc.














Simulated Hydrograph of Dry Year (19







100 -










Vx
10





Streamflow




u















0.1













0.01 -


Oct. Nov. Dec. Jan. Feb. Mar.,




7-18


Mississippi Chemical Corporation


C r_ __~ ._I L --- I


^r I I = ~ II





































Streamflow After D
for Plant Use


ilable During Mining


NoDiversion Below 3.25 fts



!


0.01


Aug. Sept.
Prepared by
P.E. LaMoreaux & Associates. Inc.


Figure 7-2














Simulated Hydrograph of Wet Y

1000 -











100 :-




S' \
100
I 1
I I

'" \\ ,\

\\




- ^ T\ / L Streamflow a
Sfor Plant Use
I.















0.1 -









Oct. Nov. Dec. Jan. Feb.

7-19


Mississippi Chemical Corporation


--i --















YLar (1960) for Brushy Creek at Point of Diversion


Available During Mining


v


June


Apr.
Pr.E a da
P.E. La Moreaux & Associates, Inc.


No Diversion Below 3.25 cfs


Sept.


Figure 7-3


Salter
tse


Mar.


r- i I I I I I


wlIs ; --s ii I III I










in the area. Leakance is generally greater north of the property with some

fairly high values in Polk County. Leakance generally declines to the south

with values near zero in Hardee County near the project area.


In this simulation, because the primary concern is the steady-state drawdown,

storage was set to zero to cause the program to iterate immediately to the

steady-state solution without any increment in time. The effects on the

potentiometric surface caused by pumping at the average rate of 7,974 gpm are

shown in Figure 7-4.


The results obtained from the Trescott model show that the maximum average

drawdown will be approximately 7.4 feet at proposed well MCLF-6. Figure 7-4

shows that the average drawdown at the nearest property line is 3.3 feet.

This is within the limits established by SWFWMD.


7.4.3 EFFECT ON WATER TABLE (Ref. 16J-2.11 (4)(c))

The proposed withdrawals through dewatering at the mine cut are not expected

to exceed the regulatory limit except in some cases where mining operations

are underway near the property boundary. During such operations, dewatering

at the property boundary may exceed 3 feet for a period of as much as 90 days

where the saturated thickness of the Water-Table Aquifer is great and (or) the

transmissivity of the aquifer is high.


The dewatering with distance diagram (Figure 7-5) represents the average case

since, over most areas of the property, the transmissivity of the Water-Table

Aquifer averages about 2,500 gpd/ft. On the western end of the property where

a higher transmissivity prevails, the effect will be more pronounced.


7-20


I~ -I


















Cone of Depression Resulting from Pumping the Proposed
Well Field at an Average of 7,974 GPM (11.48 mgd)


:... ..






. .. ...... .......... .

Si:iiiiii.iii i I "


Si.


.J-.............


0............
. ...I



.1l


~ ----- ---- L ----- -~ ----------.------~.~---~-----~CII~' ~Bas~--~--~-~-IC li~n~l-i~


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i .... ............
I i

i,,,,,. ,,, ,,,,o ,,,,,,


CONTOUR SHOWS LINE OF EQUAL
. ii:t:: DRAWDOWN IN FEET BELOW
: STATIC WATER LEVEL

UOA SYMAP OF STEADY STATE DRAWDOWN ON MISSISSIPPI CHEMICAL CO. PROPERTY



JULY 1, 1976


DATA VALUE EXTREMES APE


."?7 ..58


ABSOLUTE VALUE EANGE APPLYING TO EACH LEVEL
('MAXIMUM' INCLUDED IN HIGHFST LEVEL ONLY)
IuNIMUM ,C. .50 1 .0i 1.5C
xIMUM .,n 1.00 1 .5 2.00


P E NORTH I

PIE.P d by.
P.E. La Moreaux & Associates. Inc.


ABOVE
2,0P 2.50 3.0C 3.50 4.00 4.50 5.00
2.50 3.00 3.50 4.00 4.50 5.00


PERCENTAGE OF TOTAL ABSOLUTE VAL"lE RAh.,E APPLYING TO EACH LEVEL

10.C 10 10.00 10.0C 10.C0 10.00 10.00 10,CO 10.00 10.00 10.00


FREQUENCY DISTRIPUTION 0O DATA POINT VALUES IN EACH LEVEL
LEVEL 1 2 4 5 6 7 8 9 10 n
.-........ -. .........- = ****-**** xxxxxxxxx "6oOnOOOOO" e9eee9eee 11*11seeoee1 11 HNHHHHHNH
----, ~~~~~~ --------- zr.#.6444#+ HXYXIXXXX 000000000 6869869099 assllIss 11ISIIS1 HAHNHAIA
S .........--- ========;;= ******* XXXXXXXXX 000000000 0B9000000 111111111 111111111 HHHHMHHHH
SYlBOLS ....1.... I ----.---- .:.=4==== ,****5.** xxxx6xxx 000070000 0e0999099e 5e916 im iWl.915 HHHHAHHHH
---- ... .... = ** **** xxxxxxxxx 00ononoo0 eeeoeeeee $eelal 11111111S a HHHHHHHHH
...------ ........ ,.s **,****,* Rxxxxxx 000000000 eeeeeeee 1l11lll1 1151i11SII HHHHHNHHH
rFI[. pl 177 15 1 t 116 PyV Ah 4L7 42 61 11


-p -m --~ I--*-r~-- ~II --I" I I -ll-~--W-..Prp-dbls~~L PC ~-~I I I











An analysis using the average case solution indicates that, assuming a

minimum level is established at 5 feet below land surface and an average

saturated thickness of 15 feet, the average distance from a mining cut that

dewatering can exceed 3 feet below the minimum level is 230 feet. Since

Mississippi Chemical Corporation intends to mine as close as 50 feet to the

property boundary, adjacent landowners will be contacted to inform them of

the possibility of dewatering and obtain a waiver of complaint. The waivers

of consent so obtained will comprise Exhibit E of the application.


In addition, mining techniques will be utilized, where feasible, to limit the

effects of dewatering with distance.


7.4.4 EFFECT OF WITHDRAWALS ON WATER LEVEL OF OFFSITE LAKES
(Ref. 16J-2.11 (4)(d))

No lowering of offsite lake-water levels of more than one foot will result from

the proposed withdrawals since there are no lakes near any proposed mining

operations that are not now owned or otherwise controlled by the permitted.


7.4.5 MAXIMUM LOWERING OF THE POTENTIOMETRIC SURFACE
(Ref. 16J-2.11 (4)(e))

For the prevention of possible salt-water encroachment, the potentiometric

surface should not decline below mean sea level (MSL). The minimum water level

in the wells at the proposed plant site during May, 1976, was about 20 feet

above MSL. The steady-state drawdown at the proposed well field as derived

from the aquifer model was 7.4 feet. Therefore, 12.6 feet of drawdown will

be available and the potentiometric surface will not be lowered below mean sea

level as a result of pumping from the proposed well field.


7-22






















Water-Level Declines with Distance from a Mining Cut as
Related to Thickness of the Shallow Water-Table Aquifer





so teeth





Oeet
sol:
e'

10-
coo T = 2,500 gpd/f t.
S = 0.15
t = 30 days
so= saturated thickness a
S/ Water-Table Aquifer
15




P.E.

20 I I I I I I
-n 0 100 200 300 400 500 600 700
' Distance from a mining cut in feet
C
C-

(n










7.5 EXCEPTIONS

Exceptions may be granted to Section 16J-2.11 (2), (3) and (4) for the

following reasons:

"The Board for good cause shown may grant exceptions to the provisions
when after consideration of all data presented, including economic
information, it finds that it is consistent with the public interest."
16J-2.11 (5)


The proposed Brushy Creek storage basin will reduce the rate of flow on Brushy

Creek by 0 to 46 percent depending upon the amount of streamflow as discussed

more fully in Section 7.4.1. A special exception to Section 16J-2.11 (4) is

requested since the proposed diversion of surface water will not alter the

low-flow conditions of the stream, but will divert an increasing percentage

of the flood flows above 3.25 cfs. This diversion will decrease the water

demand upon the Floridan Aquifer by an average of 5.49 mgd, which is consistent

with good water resource management and with the interest of the public.


7.6 OTHER PERMIT APPLICATIONS

Additional applications for permits will be submitted in the future.


Under Chapter 16J-1, "Works of the District", permits may be required to:

to, withdraw water from, discharge water into, place construction
within or across, or to otherwise make use of the works of the Southwest
Florida Water Management District."


Under Chapter 16J-3, "Regulation of Wells", permits may be required to:

to construct a water well, and/or construct test or foundation
holes."


6__7-24










Under Chapter 16J-4, "Management and Storage of Surface Water", permits may

be required to:

to construct, alter, abandon or remove any dam, impoundment,
reservoir, appurtenant work, or works which:
(a) Impounds water on an area exceeding forty (40) acres by means
of dams and appurtenant works.
(b) Diverts water from an area exceeding forty (40) acres by means
of dikes, levees, fills or other means, including upstream
dams and appurtenant works, impoundments, reservoirs or works.
(c) Reroutes, restrict, or alters the rate of flow of a stream or
other watercourse which drains a watershed having an area
exceeding five (5) square miles."


Additionally, permits may be required:

to operate or maintain any dam, impoundment, reservoir,
appurtenant work, or works which:
(a) Impounds water on an area exceeding one hundred and sixty (160)
acres by means of dams and appurtenant works.
(b) Diverts water from an area exceeding one hundred and sixty (160)
acres by means of dikes, levees, fills or other means, including
upstream dams and appurtenant works, impoundments, reservoirs or
works.
(c) Is equipped with a headgate, valve or other operable structure
which impounds on or diverts from an area exceeding forty (40)
acres or which is located on a stream or other watercourse."


7-25


3--




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