Heavy Metals in the Environment: Using Wetlands for Their Removal - Chapter 11 ppt

CONTENTS Evaluation Concepts ...122 Emergy Evaluation...122 Economic Valuation ...124 Methods ...125 Lead Filtered by the Wetland ...125 Measurements of Wetland Status ...125 Energy and

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The Ecological Economics of Natural

Wetland Retention of Lead* Lowell Pritchard, Jr.

CONTENTS

Evaluation Concepts 122

Emergy Evaluation 122

Economic Valuation 124

Methods 125

Lead Filtered by the Wetland 125

Measurements of Wetland Status 125

Energy and Emergy Evaluation 125

Economic Analysis 126

Results 130

Lead Retained by the Swamp 130

Emergy Evaluation of Impacted Wetlands 130

Emergy Evaluation of Lead Smelter-Chemical Recovery System 132

Comparison of Treatment Systems 134

Economic Analysis Using Money 135

Discussion 137

Emdollar Evaluation of Wetland Lead Retention 137

Economic Valuation of Wetland Lead Retention 137

Comparison of Emergy and Economic Evaluations 138

Wetland Potential for Lead Filtration in the Nation 139

Implications for Environmental Policy 139

Summary and Conclusions 140

Acknowledgments 141

With the reorganization of the biosphere by human economic and industrial development, a new and more symbiotic pattern of environment and economics is emerging Linked by the biogeochemistry of chemical elements, ecological systems, particularly wetlands, are becoming

* Condensed by the Editor.

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122 HEAVY METALS IN THE ENVIRONMENT: USING WETLANDS FOR THEIR REMOVAL

recognized as part of the economy through their work in filtering toxic substances such as heavymetals Increasingly, wetlands have been found to be filters of many wastes of the economy whichcan be retained in the landscape to mitigate the impact of economic activity This chapter is anevaluation of a Florida wetland system which filtered large quantities of lead from the discharge

of a battery processing plant Field methods were used to compare treatment wetlands with referencewetlands Comparison was made between emergy analysis (spelled with an “m”) and mainstreameconomic analysis methods in evaluation of wetland services in ﬁltering a toxic metal An estimate

is made of the potential value of wetland ﬁltration of lead to the state and nation

Two systems for recovery of lead batteries and lead-contaminated waters were evaluated:(1) wetland ﬁltration of wastewaters from acid washing of batteries; and (2) chemical treatment ofwastewaters at a lead reprocessing smelter Both systems were evaluated with economic and emergy

methods From 1970 to 1979 the Sapp Swamp, Steele City Bay, in Jackson County, FL, receivedacidic, lead-contaminated wastewaters from a battery reclamation operation The 29-ha cypress-tupelo wetland is the Superfund site described in Chapters 1 and 5 The technological batteryoperation is a lead smelter–chemical treatment operation in Tampa, FL The process of producinglead batteries was also evaluated using emergy, obtaining the transformity of lead batteries (FigureA11B.7) needed in calculations

EVALUATION CONCEPTS

This chapter uses two concepts of evaluation: (1) environmental value based on the work ofnature and humans in generating a product; (2) economic values based on human perceptions andmarket prices for a product

Emergy Evaluation

Emergy evaluation provides common units for comparison of environmental and economicgoods and services After all the inputs are identiﬁed with systems diagramming (example: Figure11.1), each is evaluated in emergy units and summed Emergy is the energy of one kind requireddirectly or indirectly for their production

For instance, production of a bushel of corn may require many kinds of available energy fromsunlight, wind, rain, fertilizer, equipment, and human labor, but with emergy evaluation each isexpressed in units of one kind of energy previously used up The production of wind energy requiressolar energy, and the production of rain requires solar energy and wind energy (which requiressolar energy) Fertilizer, equipment, and human labor are transformations of fossil fuel energy (theproduction of which required solar energy and geologic energy) The amounts of solar emergynecessary are back-calculated

Emergy is thus a measure of environmental work (Odum, 1986, 1988, 1996) contributing toproduction Its unit is the solar emjoule (sej — see Chapter 4) By measuring the emergy previouslyrequired per unit energy, the method recognizes differences in energy quality of environmental andeconomic inputs The emergy per unit energy is called transformity (sej/J) With each successivetransformation process, the transformity increases, thus measuring the position of an item in anenergy hierarchy

Emergy ﬂow per time is called empower The higher the empower the greater is the economicand ecological value of production (as deﬁned in emergy units)

Emergy/mass ratios are convenient for calculating the emergy of materials which are oftenmore easily measured in mass rather than energy terms

Although national emergy use and gross national product are partially independent (see cussion), the emergy/money ratio of the overall economy in a given year (emergy use/gross national

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THE ECOLOGICAL ECONOMICS OF NATURAL WETLAND RETENTION OF LEAD 123

product) can be used to estimate the average emergy behind purchased services for which detailedenergy information is lacking (Odum, 1991)

For clarity, Table 11.1 provides a summary of deﬁnitions for emergy evaluation terms The emergy value of a wetland depends on the energy captured and used in biological production(often measured by gross primary production) Calculation of stored emergy evaluates storages andstructure, for instance, peat in cypress swamps or tidal channels in salt marshes (Odum andHornbeck, 1996)

As systems diagrams show, the ecological goods, services, and storages considered economicamenities are all direct or indirect products of the input energy ﬂows Figure 11.1 is an energydiagram of the wetland receiving lead-polluted acid water It shows the ecological system generating

a storage of lead-adsorbing sediments but experiencing a toxic effect from acid waters Thesediments adsorb lead from the water column and return lead to the water column as they decay

Emergy The energy of one type required directly or indirectly in transformations to

generate a product or service Solar emergy Solar energy required directly and indirectly to produce a product or service

(units are solar emjoules — sej) Transformity Emergy per unit energy for a given product or service in a system

Solar transformity Solar emergy per unit energy (units are solar emjoules/joule — sej/J)

Emergy per unit mass Energy of one type required to generate a flow or storage of a unit mass of

a material (units are sej/g) Empower Emergy flow per unit time (units are sej/year)

Emergy/dollar ratio Ratio of emergy flow to dollar flow, either for a single pathway or, more

commonly, for a state or a nation, where annual emergy use is divided by the gross economic product (units are sej/$)

Sources: Odum, 1988; Odum, 1991.

H+ Pb Water

Pb Sediment

Wind

Sun

Swamp

Aesthetics Wildlife Trees

plants

Clean water

To the Regional Economy

Toxic Effect

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Flows out of the system include some lead in water (though a lower concentration than the inﬂow)and some lead in suspended sediment The ecological system also generates aesthetic, wildlife, andtimber value to the regional economy

Economic Valuation

In mainstream economics, goods and services are valuable to the extent that they are useful toconsumers Some wetland contributions to people are directly useful (bird watching, boating,recreational fishing) and are called “final” goods (Scodari, 1990) Intermediate wetland goods arevaluable to consumers because they serve as factors of production for goods which are, in turn,enjoyed directly (for example, wetland trees may be a factor in the production of wood for fuel orpulp for paper and wetland peat may be a factor of production in electricity) Where well-developedmarkets exist for wetland final and intermediate goods, it is argued that prices reflect their value

to society Where markets do not exist, economic value must be determined in other ways

to measure the value to society of nonmarketed wetland services such as heavy metal retention byusing the cost of a substitute for that service If society is willing to bear that cost, the value ofthe service must be greater than or just equal to the cost (A different concept of replacement costinvolves measuring the cost of actually replacing a natural wetland and its functions with aconstructed wetland [Anderson and Rockel, 1991].)

The ability of wetlands to retain heavy metals such as lead is an intermediate wetland good

In this economic paradigm, people do not actually value the intermediate good of heavy metalretention; they value the final goods of clean water or refined lead (or the output of the industriesusing heavy metals) The demand for wetland retention of heavy metals (which represents thevalue they place on that service) is a “derived demand” — derived from the value of final goods

by a ﬁrm which will use the intermediate good to satisfy the demands of consumers (McCloskey,

1985, p 450)

To use the replacement cost method of valuing wetland service, the derived demand is assumed

to be perfectly inelastic, which means that even with a higher-cost substitute, a ﬁrm (or society)would demand the same amount of lead retention as with “free” treatment by a natural wetland.For a discussion of why this assumption is made, see Appendix A11A

Wetland products and services such as lead retention are called positive externalities These aresocietal benefits that arise from wetlands which cannot be captured by the wetland property owner.Wetland production of waterfowl, for example, benefits society (especially hunters and bird watch-ers), but this benefit is external to the private property owner’s decision-making boundary If theowner is not personally interested, then he or she is likely to sell or convert the wetlands into otheruses Likewise, negative externalities (also called social costs) are costs “falling beyond the bound-ary of the decision-making unit that is responsible for those costs” (Bromley, 1986), such as wetlanddestruction from pollution If decisions are to be made about the socially efficient provision ofwetland products and services, the magnitude of these externalities must be ascertained

In summing benefits and costs over time, mainstream economics stresses the importance of thetime value of money It is common practice in economic analysis to discount the value of futurebenefits and costs Discounting has been extensively criticized and defended in the literature (see,for example, Pearce and Turner (1990, pp 211–225), but the idea is that real current benefits (andcosts) are given more weight than prospective future benefits (and costs) Several reasons exist forsuch discounting: inflation erodes the value of benefits over time, there may be some risk that thefuture benefits will not materialize, and individuals are impatient (Randall, 1987, p 239; Pearceand Turner, 1990) Because the calculations here are in constant dollars, because the concern iswith the longer run, in which case risk has less meaning, and because societal rather than individualvalues are considered, these three components (inflation, risk, and impatience) should not influenceour analysis

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Another reason for discounting is that, on average, the economy is growing, and investmentsyield a positive return If the rate of return is 4% per year, then to receive $100 a year from now,one would need to invest about $96 today So it can be said that the present value of a promise of

$100 a year from now is $96 The rate of real growth in gross national product over the past 20years has been about 4% (U.S Department of Commerce, 1990), which may be taken to represent

an appropriate discount rate

The discounted sum of annual net benefits over time is the present value of those benefits Forlonger periods of time it is usually called the capital asset value of those annual net benefits Forsuch longer time periods, it is equivalent to the amount of money which would need to be invested

at a rate of interest equal to the given discount rate such that the return would equal the net beneﬁt

At a zero discount rate, the present value is the sum of expected net beneﬁts The discounting/incomecapitalization formula is given in Appendix A11

METHODS

The ﬁrst step in valuing the work of the wetland in retaining lead was to quantify the amount

of lead actually held in the wetland sediments The cost of providing this service was then estimatedusing the emergy of lost wetland productivity The cost of replacing the wetland service with atechnological treatment alternative was then calculated ﬁrst in emergy terms and then in dollars

Lead Filtered by the Wetland

The amount of lead retained in on-site wetlands and in Steele City Bay was estimated based

on data in Watts (1984) and Mundrink (1989) The total lead released over the lifetime of the plantwas calculated using the estimated number of batteries processed per year and the average con-centrations of lead in the electrolyte

Measurements of Wetland Status

To evaluate the loss of wetland productivity in the ﬁeld, the gross primary production wasestimated in 1991 for each of three ecosystem components — trees, water lilies, and aquaticproducers The swamp was divided into productivity classes based on the vegetation structure, andthe various productivity values found in 1991 were used to estimate swamp production in 1981based on observations of vegetation structure in Lynch (1981) This provided another data point tocrudely estimate swamp recovery rates To consider ecosystem effects other than productivity loss,benthic macroinvertebrate species diversity was measured, and a bioassay of toxicity was madewith tree seedlings

The emergy value of the trees killed was evaluated, but was not included in the value of wetlanddamage, because for the most part dead trees were not lost to the system but rather were ecologicallyrecycled The emergy value of the loss of wetland production over time represented the realecological damage The transformity of wetland gross primary production for an undamagedforested wetland in the Florida Panhandle was estimated based on average environmental inputs

of solar energy, wind energy, rain, and runoff This transformity was applied to the loss of grossprimary production for the wetland system draining the Sapp Battery site, based on measurementsfor 1991, estimates for 1981, and a number of projected recovery rates

Energy and Emergy Evaluation

Energy–emergy evaluation (Odum and Arding, 1991; Huang and Odum, 1991; Odum, 1996)was used to evaluate the lead battery production, the wetland ﬁltration system, and the chemical

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recovery system First an energy systems diagram was constructed (Figures 11.1 and 11.2), detailingthe system boundaries, important sources, components, ﬂows, and interactions These were arranged

to show the hierarchy of components (more dilute energies converge to concentrated energies fromleft to right) and the quality of sources (arranged outside the boundary from left to right in order

of quality) Pathway lines show ﬂows of energy, materials, and information

Emergy evaluation tables with ﬁve columns were prepared from the diagram:

Column 1: Item number indicating the table footnote detailing calculations

Column 2: Item from the diagram to be evaluated

Column 3: Data in typical units (joules, grams, or dollars)

Column 4: Solar emergy per unit (solar emjoules per unit: sej/J, sej/g, or sej/$)

Column 5: Solar emergy, in solar emjoules; the product of columns 3 and 4

For example, Table 11.2 evaluates annual ﬂows of inputs and products and Table 11.3 evaluatesstored quantities From the emergy evaluation table emergy indices were calculated to help inter-pretations

chemicals, equipment, and labor.

Battery

To

Water Lead

Acid Plastic Casings

Wastewater

Sludge smelter

teries

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with and without Lead/Acid Discharge, 1991

Transformity or Emergy/Mass (sej/unit)

Solar Emergy (sej)

Without discharge

Energy inflows

Transformity = 1.0 (by definition).

2 Wind energy Diffusion and gradient values for Tampa, FL; Odum et al., 1987, p 25 ff.

Total = Summer + Winter = 2.13 E10 + 8.09 E10 = 1.02 E11 J/y

Transformity = 623 sej/J (Odum et al., 1987, p 4).

3 Rain, chemical 1.51 m/y (Fernald, 1981) Gibbs free energy of rain relative to seawater,

4.94 J/g

(29.2 E4 m 2 )(1.51 m/y)(1000 kg/m 3 )(4.94 E3 J/kg) = 2.18 E12 J/y.

Transformity = 1.54 E4 sej/J (Odum et al., 1987, p 4).

4 Run-in Drainage area estimated equal to wetlands area from USGS map Annual runoff

rate for Northwest Florida 0.63 m/y (Kenner, 1966 in Fernald, 1981)

(29.2 E4 m 2 )(0.63 m/y)(1000 kg/m 3 )(4.94 E3 J/kg) = 9.09 E11 J/y

Transformity = 41 E4 sej/J (Odum et al., 1987, p 4).

5 Gross primary production (undamaged) Reference forest production from Table 5.4 :

1.85 E8 J/m 2 /y (1.85 E8 J/m 2 /y)(29.2 E4 m 2 ) = 5.39 E13 J/y.

Transformity calculated from sum of emergy of 3 and 4 above divided by energy of gross primary production.

(7.10 E16 sej/y)/(5.39 E13 J/y) = 1317 sej/J.

6 Lead inflow Lead in process wastewater 0.27 g/battery 1.25 E7 batteries processed

by Sapp in 10 years

Total wetland area 29.2 ha

(1.25 E7 batteries/10 years)(0.27 g Pb/battery) = 3.38 E5 g/y

Emergy/mass of lead = 7.3 E10 sej/g.

continued

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The technological substitute was an existing wastewater treatment plant operated by a secondarylead smelter in Tampa, FL Operation and maintenance cost data were supplied by the ﬁrm (NeilOakes, personal communication), and capital costs for the treatment plant were estimated using acomponent cost approach (James M Montgomery Consulting Engineers Inc 1985, p 661) forspeciﬁc wastewater treatment processes and equipment

The ﬁnancial cost of replacing the wetland’s work in lead retention was calculated as the sum

of the capital cost of building a treatment facility and the operating costs to treat an amount of leadequal to that which was retained by the wetland The operating cost was obtained by multiplyingthe unit operating costs (dollars/kilogram) to treat lead in the treatment plant by the amount of lead(kilograms) retained in the swamp

While the total beneﬁt of allowing the wetland to treat lead waste was calculated from itsreplacement cost, there were some economic costs incurred in this wetland use The ﬁnancial cost

of the loss of standing timber from the wetland was calculated from the amount of wood in treeboles in the standing stock in the reference forest (Location RF, Figure 1.3) and from current marketstumpage values for wetland trees The data from the 5 × 20-m tree plots were converted toaboveground stem mass using the following regressions from Day (1984):

log10 dry weight cypress (kg) = –0.99 + 2.426 log10 dbh (cm)log10 dry weight hardwoods (kg) = –1.0665 + 2.4064 log10 dbh (cm)where dbh is the diameter at breast height

The ﬁnancial cost of the loss of timber production (as distinct from the loss of standing timber)was estimated from the same market stumpage values of wetland wood multiplied by the estimatedannual wood production from Johnson (1978)

With wetland treatment, lead that with chemical treatment would be precipitated and recycled

to the economy was instead bound up in wetland sediments This economic loss of lead metal wascalculated according to the market value of lead (Woodbury, 1988)

The costs of wetland treatment (loss of timber, timber production, and lead metal) weresubtracted from the benefits of wetland treatment (the replacement cost) to calculate the netbenefit of using wetland treatment Since the stream of benefits and costs occurred over time,the mainstream economic values of future benefits and costs were discounted at 4% The formulaused was

where PV is present value, NB is annual net beneﬁt, i is the discount rate, and t is the number ofyears in the future See Appendix A11

7 Lead outflow Lead inflow over 10 years = (0.27 g/battery)(1.25 E7 batteries) =

3.38 E6 g Lead retained in wetland = 2.28 E6 g (this study)

(3.38 E6 g – 2.28 E6 g)/10 years = 1.11 E5 g/y.

8 Gross primary production (damaged) Weighted average of wetland production from

Table 5.4 : 5.73 E7 J/m 2 /y

(5.73 E7 J/m 2 /y)(29.2 E4 m 2 ) = 1.673 E13 J/y.

Transformity = 1317 sej/J (calculated in note 5 above).

(29.2 ha) with and without Lead/Acid Discharge, 1991

1+i( )t

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Table 11.3 Emergy Evaluation of Storages in a Northwest Florida Swamp (29.2 ha)

with and without Lead-Acid Discharge, 1991

Raw Units (sej/unit)

Transformity or

Without discharge

With discharge

Notes:

1 Water Depth above peat = 0.5 m Depth of peat = 0.5 m Percent moisture =

89.6% Density of wet peat = 1.0 E6 g/m 3 Gibbs free energy of water = 4.94 J/kg.

Water in peat = (29.2 E4 m 2 )(0.5 m)(1.0 E6 g/m 3 )(0.896)

(4.94 J/g) = 6.54 E11 J.

Water above peat = (29.2 E4 m 2 )(0.5 m)(1.0 E6 g/m 3 )

(4.94 J/g) = 7.30 E11 J.

Total water above and in peat = 1.38 E12 J.

Transformity = 4.1 E4 sej/J (Odum, 1992b).

2 Lead in water (background) Pb conc = 2.0 E-10 g Pb/g water (Förstner and

Wittmann, 1983, p 87, avg for freshwater).

(29.2 E4 m 2 )(0.5 m depth)(1 E6 g/m 3 )(2.0 E-10 g Pb/g water) = 29.2 g Pb.

Emergy/mass = 7.3 E10 sej/g ( Table A11 B 6 ).

3 Wood Mass from reference forest tree plots = 34.4 kg/m 2 Wood energy 3500

kcal/kg (Chapman & Hall, 1986, p 467)

(29.2 E4 m 2 )(34.4 kg/m 2 )(3500 kcal/kg)(4186 J/kcal) = 1.47 E14 J.

Transformity = 3.2 E4 sej/J (Odum, 1992b, p 27).

4 Peat Depth 0.5 m Moisture 89.6% Density of wet peat 1.0 E6 g/m 3

Peat energy 2.15 E4 J/g (Odum, 1992b, p 27).

(29.2 E4 m 2 )(0.5 m)(1 – 0.896)(1.0 E6 g/m 3 )(2.15 E4 J/g) = 3.26 E14 J.

Transformity = 1.7 E4 sej/J (Odum, 1992b, p 27).

5 Lead in peat (background) Pb conc = 1.8 E-5 g Pb/g sediment (Okefenokee

Swamp, GA; Nixon and Lee, 1986, p 116)

(29.2 E4 m 2 )(0.5 m)(1 – 0.896)(1.0 E6 g/m 3 )(1.8 E-5 g Pb/g peat) = 2.73 E5 g Pb.

Emergy/mass (see note 2).

6 Lead in water (contaminated) Pb conc = 5.8 E-8 g Pb/g water (Ton, 1990).

(29.2 E4 m 2 )(0.5 m depth)(1 E6 g/m 3 )(5.8 E-8 g Pb/g water) = 8.47 E3 g Pb/ha.

Emergy/mass (see note 2).

7 Wood Mass (weighted average of tree plots) = 7.05 kg/m 2 Wood energy 3500

kcal/kg (Chapman & Hall, 1986, p 467).

(29.2 E4 m 2 )(7.05 kg/m 2 )(3500 kcal/kg)(4186 J/kcal) = 3.02 E13 J.

Transformity (see note 3).

8 Lead in peat (contaminated) Total Pb in peat estimated at 2276 kg for 29.2 ha

( Figure 5.1 ).

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RESULTS Lead Retained by the Swamp

Lead retained in on-site wetlands was estimated to be about 1000 kg using Watts’ data (1984).Lead retained in Steele City Bay was estimated at 1354 kg The average of lead concentrationsreported by Ton (1990) for sediments in Steele City Bay was 52.1 kg/ha, or 1198 kg in all 23hectares The average of the two values for Steele City Bay was 1276 kg Thus, the total leadretained in on- and off-site wetlands was estimated at 2276 kg For details on calculations, see

Pritchard (1992, Appendix E)

Assuming a linear rate of increase in battery processing by Sapp Battery from zero at thebeginning of 1970 (when the plant opened) to a peak of 50,000 batteries per week in 1979 (Watts,1984), the total number of batteries processed was estimated at 12,525,000 Cumulative lead releasefrom those batteries over 10 years was estimated to be between 1528 and 6162 kg of particulateand dissolved lead, based on data on electrolyte content from Watts (1984) (calculations in Pritchard,

1992, Appendix E) At a secondary lead smelter in Tampa, FL, process wastewater contained about0.27 g lead for every battery This, multiplied by the estimated 12,525,000 batteries processed atSapp, would put cumulative lead releases at 3382 kg

The removal rate is the percentage of lead released that was retained in the wetland system.Using the range of concentration given by Watts (1984), the removal rate for lead by the wetlandsystem was between 37 and 100%, with a middle value of about 67% based on data on wastewaterlead concentrations at a secondary lead smelter in Tampa, FL

Since it is likely that the rate of battery processing at Sapp Battery increased exponentiallyrather than linearly to its peak rate as was assumed, 12 million batteries processed is probably anoverestimate, making the actual removal rate higher than the calculated removal rate However,emergy and economic calculations that follow are based on the amount of lead retained rather than

on the removal rate We evaluated the work the wetland did, not the work it did not do (i.e., leadnot absorbed from the waters ﬂowing out)

Emergy Evaluation of Impacted Wetlands

The emergy per gram of lead metal was calculated by summing environmental work and humanwork in extracting, reﬁning, and processing in Appendix A11 and was 7.3 E10 sej/g

The emergy evaluation of the wetlands which received wastewater from the Sapp Battery plantbased on the diagram in Figure 11.1 is given in Tables 11.2 (ﬂows) and 11.3 (storages) The twolargest sources, rain and run-in, were taken as the main annual emergy input to the swamp system.The reference forest wetland (Location RF) was used to represent the productivity of the impactedwetland before damage began (line 5 in Table 11.2) The transformity of gross primary productionbased on productivity values from the reference forested wetland was about 1300 sej/J

Productivity data (Table 5.6) were used to estimate the actual level of energy processing in theswamp in 1991 (line 8 in Table 11.2) Remote sensing information from a previous study (Lynch,1981) was used to estimate the energy ﬂows and transformations in the local wetlands system fortwo points in time Table 5.4 shows the reduction in empower per square meter due to the acidicdischarge for 1991 In Table 11.4 these estimates are multiplied by the appropriate areas to convertthem to total empower for the wetland complex (calculations in Pritchard, 1992, Appendix F)

In the absence of detailed time-series data, several simplifying assumptions were made It wasassumed that the decrease in empower of the system was linear from the beginning of operations

at Sapp Battery to its closure, a period of 10 years Lynch’s measurements were made in 1981,soon after the cessation of operations; the data he cites are taken as the minimum productivity ofthe system Linear recovery is also assumed up to 1991

Tiêu đề	The Ecological Economics of Natural Wetland Retention of Lead
Tác giả	Lowell Pritchard, Jr.
Trường học	CRC Press LLC
Chuyên ngành	Ecological Economics
Thể loại	Chapter
Năm xuất bản	2000
Thành phố	Florida

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Số trang	21
Dung lượng	708,1 KB