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2017 SWANA Excellence Award Entry Composting System
Navy Whidbey Recycle
Navy Whidbey Recycle
Naval Air Station Whidbey Island
3485 N. Langley Blvd.
Bldg. 2555
Oak Harbor, WA 98278
Michael G. Grant, ISWMP Operations Manager
Oliver L. Elam, ISWMP Assistant Manager [email protected]
360-257-5481
Title: Navy Whidbey Recycle Composting System
Population: 18,240
Commodity Rate: $266/ton
Budget FY 17: $2.3 million
2017 Excellence Award Compost System Navy Whidbey Recycle
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Executive Summary Navy Whidbey Recycle (NWR) provides
Integrated Solid Waste Management (ISWM)
support services to the air station. NASWI
provides fleet, fighter and family support to
over 18,000 personnel in 46 departments at
three locations on Whidbey Island. NWR began
as a small operation in 1990, increasing in size
and scope with each year of operation. An EPA
mandate required closure of the base-operated landfill in 1993 to protect an adjacent
sole source aquifer. With the closure of the landfill and progressive federal orders and
directives, waste management including enhanced recycling and re-utilization became
key elements of service to the station. By 2000, Navy Whidbey Recycle had added
composting to the operation to include five in-vessel digesters for composting food and
yard waste generated on the air station. In 2005 the program innovation continued
adding three more in-vessel digesters to compost bio-solids generated by the Navy
owned wastewater treatment plant.
1. Design and Planning of Composting System
1.1 Planning Process Considerations
This facility began as a demonstration project to test the economic and technical
feasibility of composting a variety of organic materials at U.S. Navy bases. The facility
processes source separated organic materials including yard debris (grass clippings),
clean wood, food, mixed waste paper, waxed corrugated containers, and biosolids into a
marketable high quality compost product. NAS Whidbey Island is a busy air station with
squadrons flying the EA-18G Growler, P-3 Orion, P-8, and the EP-3E Aries. It was
imperative that the composting method would not attract birds and other vectors that
would interfere and endanger the safety of flight crews. This was the most important
factor in selecting the in-vessel composting method along with simplicity and ease of use
as well as for its control of odors and leachate from the composting process. The system
utilizes modified roll-off containers as the composting vessels. A controlled amount of air
is blown into the bottom of each container to aerate the composting materials. Another
fan is used to draw air out of the top of the containers and into a biofilter where odor
can be removed. The sealed composting vessels also contain leachate that may result
from the composting process. These are captured and reused.
2017 Excellence Award Compost System Navy Whidbey Recycle
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Figure 1: Site map of Compost Facility
1.2 Important Decision Factors
The important factors considered in the
planning process were site selection,
compost method and economic drivers.
1.2.1 Site Selection
The composting facility sits on 10 acres of
government owned property located in an
unpopulated area of NAS Whidbey Island.
It is adjacent to the landfill site which was
closed in 1993 due to an EPA required
mandate which enabled NWR to add
composting to our operations.
1.2.2 Compost Method
NWR choose to utilize in-vessel
composting to better control
environmental factors such as odor,
leachate, vermin and weather. In-vessel
composting gives us the flexibility to add
more digesters if needed. In 1999, we
began with 6 in-vessel digesters for
composting food and yard waste
generated on the air station. In 2005, two
more in-vessel digesters were added to
compost bio-solids generated by the Navy
owned wastewater treatment plant.
1.2.3 Economic Drivers
Presidential Executive Orders and DOD instructions require installations generating more than one ton of solid waste to develop an ISWM and Qualified Recycling program with an annual goal to divert 50% of solid waste from the landfill. NWR averages a 72% diversion rate, with 30% being compost. By composting food and yard waste along with biosolids we reduce disposal costs and decrease the solid waste going into the landfill.
1.3 Site and Operational Design
The major features of the compost facility are show
in the diagram below.
In Vessel Compost Bins
Office and Compost Computer Control System
Bio-Filter
4,000 Gallon Underground Leachate Tank
10,000 Gallon Undergrround Storm Water Tank
Tipping and Mixing Building
2017 Excellence Award Compost System Navy Whidbey Recycle
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Figure 2: Overview of the Compost Facility
1.4 Compatibility of compost program with local environment and solid waste
management
The EPA required the closure of the lagoon treatment plant previously used to receive
waste water. In 2006, the new Waste Water Treatment Plan was implemented with the
capability to dewater biosolids. NWR then expanded our composting abilities to take
dewatered biosolids and converting it to a usable commodity.
1.5 Discuss the overall merits and impact of the composting system. What is unique
about this system that takes it to the “excellence” level?
NWR is the only Navy Facility that utilizes in-vessel composting. Our composting system
allows for expansion by adding additional in-vessel digesters. Due to increased
operations, the process controller was upgraded and a second auger mixer was
purchased to support the increased volume of biosolids materials. Odor is controlled by
with proper management and maintenance of the biofilter for the system. Vectors do
not pose a problem because most of the composting takes place in the enclosed vessel.
The leachate collection tank is fitted with a high level warning alarm and is checked on a
daily basis. Rainwater is collected in a 10,000 gallon tank and is used in the composting
process by using in the remix. Each in-vessel container is sealed along the door and lid
and there is a drain valve that allows the leachate to drain out of the vessels.
2017 Excellence Award Compost System Navy Whidbey Recycle
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2. Use of Equipment/Systems and Technologies
Composting Vessel Loading composting vessel
2.1 In-Vessel Composting – A State of the Art Process
Food/Yard Compost Process
Tipping- All woody materials (bulking material) ready for use in the composting process
are placed outside on one end of the curing pad or next to the curing pad and
composting bins. Materials tipped in the tipping and mixing building are placed in areas
for specific types of materials: one area for yard waste, one area for food waste and
another area for mixed waste paper and waxed cardboard. Once tipped, the materials
are inspected for contaminants and non-compostable materials.
Preprocessing- Preprocessing involves the grinding of woody materials prior to being
introduced into the composting process. Woody materials, such as pallets, crates, brush
or small trees and clean lumber is staged and processed into chips by the base's portable
grinder.
Mixing and Loading-The in-vessel composting system is a batch system. It begins with
the blending of materials in the mixer truck to produce a consistent mix of materials.
Food containers are emptied directly into the mixer truck. Once loaded in the mixer
truck, the food materials are blended with yard debris (grass clippings), waxed
cardboard, mixed waste paper and bulking material. Water is then added for 56%
moisture content ensuring a well-balanced mixture of ingredients. The mixer truck
comes equipped with a digital scale so that ingredients can be measured accurately.
Once all of the materials are loaded in the mixer, it is run long enough to ensure
thorough mixing. The mixer truck also contain knives that can be used to chop up whole
produce and waxed corrugated containers so they break down more readily in the
composting process. After blending, the mixer truck discharges the materials onto the
tipping floor. The front-end loader is used to load the product into the composting
vessel.
Food/Yard Composting-Once the composting vessels are filled the materials are then allowed to compost for 14 to 21 days. Manual temperature readings are also collected daily from three separate ports at three separate depth intervals each to verify the temperature is consistent throughout the vessel.
2017 Excellence Award Compost System Navy Whidbey Recycle
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If the temperature drops below the set point during the 14 to 21 day period, the materials are emptied out of the vessel and reloaded into the mixer truck for remixing to reconstitute moisture levels. After unloading and remixing, the materials are reloaded into the composting vessel and reconnected to the aeration system to restart the 14 to 21 days of composting. The purpose of this stage is to stimulate the growth of bacteria that consume the sugars, starches, fats and proteins within the feedstock materials.
Biosolids Processing-NASWI owns and operates a Sequencing Batch Reactor (SBR) Waste Water Treatment Plant (WWTP) at Ault Field. Currently, aerobically digested sludge
Dewatered BioSolids Centrifuge is dewatered and sent to NASWI’s Composting Facility for treatment utilizing an in-vessel composting system. Sludge is removed from the digesters normally when the total suspended solid levels are sufficient to warrant removal. A screw auger transports the biosolids into a roll-off container located outside the centrifuge building where several cubic yards of shredded paper are added as a bulking agent. The “raw” biosolids are stored in the roll-off container until transport to the composting facility is scheduled. After arriving at the composting facility, the raw biosolids are loaded into a mixer truck with a frontend loader and mixed with wood chips and shredded paper. Following tipping and mixing, the raw biosolids are loaded into a composting vessel using a front-end loader. Each batch is assigned a unique identification number and a folder is prepared containing information needed to demonstrate classification as EQ, Class A compost.
Dewatered Biosolids being tipped Curing-After 14 to 21 days of composting in the vessels, a roll-off truck is used to pick up
the vessel and move it to the curing pad where the commodity is emptied out of the
vessel. A front-end loader is used to create a single large static curing pile, where
materials are allowed to mature for a period of 6 to 9 weeks.
Screening and Storage-After curing, the food and yard commodity are screened to
remove contaminants and oversized and/or undecomposed wood chips. These are
considered overs and reused as bulking agent. The screened compost is ready to be
2017 Excellence Award Compost System Navy Whidbey Recycle
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stored, used or blended with other ingredients to make topsoil. Once we have the
certified analytical results, we can execute a spot sale for the food and yard compost.
Process Control System-The in-vessel composting system monitors the following
parameters on a continuous basis: temperature in each composting vessel; air flow to
each composting vessel; and pressure in the air-delivery system. Temperature is used to
control the aeration dampers to and from each individual composting vessel. A
minimum amount of air is always flowing through the containers to maintain aerobic
conditions. Top and bottom temperature set points can be established for the
composting process. The air flow and pressure sensors control the variable speed
blowers used to push air into the vessels and draw air out of the containers and into the
biofilter. Temperature set points are maintained to reduce pathogens and vector
attraction. The system monitors all composting parameters in individual composting
containers for regulatory purposes. Operators can set data collection protocols and
standard consumer software (Microsoft Excel) can be used for data management and
reporting. The system can track time and temperature parameters for every batch of
compost made in each vessel so that the operator can be sure that all materials are
meeting pathogen reduction and vector attraction requirements. In 2015, the operation
system software was upgraded which allows the compost operator to view all compost
data, create new compost batches, move batch data to different vessels, save and print
temperature history reports, view and control fan and damper settings and update or
change parameter settings.
2.2 Describe equipment used at the facility, including its efficiency and effectiveness.
Penta Mixer
In 2010, an old grinder was replaced by a Rotochopper MC266 that is diesel Tier 3
compliant. The grinder is fed by a wheeled material handler or Grapple. The wood
grinder is operated by remote control so one operator can operate two machines at the
same time making it safer and more efficient use of man hours. Compost screening is
accomplished with a Multitek 725DM Trommel screener. The trommel is very efficient at
removing larger wood chips and contamination. NWR added a second conveyor enabling
employees to remove any contaminates that maybe left in the overs.
The Penta Mixer compost collection vehicle is a
diesel Tier 4 low emission vehicle. Compostable
material is collected using a hydraulic chain driven
tote dumper. Totes are dumped into the mixer
with a low profile twin screw mixer to mix the
compostable material. The mixer was specifically
designed to contain a hydraulic driven pressure
washer and on board water tank to sanitize dirty
totes and improve cleanliness.
2017 Excellence Award Compost System Navy Whidbey Recycle
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Trommel Screener Rotochopper
2.3 Explain the facility’s waste screening procedure.
Contamination, especially from plastic film can be problematic for compost operations.
Keeping contamination out of compost starts with the customer. NWR is committed to
our outreach and education program. We encourage our base commands and food
service facilities to stop using plastic bags and plastic products and instead use
compostable paper products or reusable containers. Our goal is to promote and
encourage base wide involvement with conserving our natural resources at NAS
Whidbey Island. Our staff acts as liaisons to base departments and commands to
establish programs for recycling education, performance monitoring and feedback. A
network of command representatives are involved with NWR staff in an effort to
promote and increase recycling and composting within their division. We encourage and
promote the establishment of command Green Teams. Green Team practices include
education and awareness activities, recycling promotion, and energy reduction
measures. The teams translate federal policy in a way that encourages individual
behavior to achieve a culture of conservation.
3. Regulatory Compliance
3.1 Regulatory Compliance Food and yard compost is regulated by the state and biosolids is regulated by the EPA. Requirements and standards for the use and disposal of biosolids is administered by 40 Code of Federal Regulation (CFR) 503, referred to as §503 henceforth. Chapter 173-308 Washington Administrative Code (WAC) is a state rule adopted by the Washington State Department of Ecology (Ecology) that establishes standards, management practices, permitting requirements, and permit fee schedules for facilities that store, treat, and recycle municipal or domestic sewage sludge or biosolids, as well as sites designated for land application.
2017 Excellence Award Compost System Navy Whidbey Recycle
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3.2 Pathogen Reduction
503 Subpart D contains requirements for biosolids to be classified either Class A or Class B in regards to pathogens. If pathogens are below the threshold level, the biosolids meet Class A designation. Biosolids are designated Class B if pathogens are above the threshold value but have been reduced to levels that do not pose a threat to public health or the environment, as long as actions are taken to prevent exposure to the biosolids after their use or disposal. Class A biosolids must have maximum specified fecal coliform or salmonella densities. Following are the requirements that apply to in-vessel composting: • The temperature of the biosolids is maintained at 55°C (131°F) or higher for 72 hours, and • Either the density of fecal coliform must be less than 1,000 most probable number (MPN) per gram total solids, or salmonella less than 3 MPN per 4 grams total solids. • The above requirements must be met before the biosolids is applied to the land or when prepared to meet the requirements for EQ, Class A biosolids. • Pathogen reduction must take place before or at the same time as vector attraction reduction, thereby minimizing the potential for re-growth of pathogenic bacteria.
3.2 Vector Attraction Reduction
0
20
40
60
80
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Tem
pe
ratu
re (
de
g C
)
Days
Batch Temperature History Report
Probe…
Batch name: Bin 7 Biosolids Start Date: 2016-06-22T 14:43:40
Passed PFRP Passed VAR Started Zone 7
2017 Excellence Award Compost System Navy Whidbey Recycle
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Reducing the attractiveness of biosolids to vectors reduces the potential for transmitting diseases from pathogens contained in biosolids. §503.33 contains 10 options for demonstrating reduced vector attraction for biosolids, either designed to reduce attractiveness or prevent vector contact with the biosolids. Parameters require operators using the in-vessel composting process to demonstrate vector attraction reduction (VAR) by maintaining the biosolids at a minimum temperature of 40°C (104°F) for at least 336 hours (14 days). 3.3 Pollutant Limits
§503 establishes concentrations for nine metals, also referred to as ceiling concentrations and monthly pollutant concentration limits, which cannot be exceeded when biosolids or compost is considered for land application. Biosolids or compost must meet the monthly pollutant concentrations to classify as EQ, Class A. Our objective is to produce EQ, Class A biosolids, land application of biosolids or compost is primarily restricted by Ecology’s primary cleanup/land use regulatory document: Pollutant limits, in addition to the limits for petroleum hydrocarbons and fecal coliform are provided in Table. 3.3. Our food and yard waste compost are sampled for various contaminates as shown in Table 3.4 Table 3.3.1: EQ Biosolids Pollutant Limits Table 3.3.2 EQ Food/Yard Compost Pollutant Limits
Pollutant Ceiling Concentration Monthly Pollutant Pollutant Units Method
(mg/Kg) Concentrations (mg/Kg) Arsenic mg/kg EPA
6010B/3051
Table 1 of §530.13 Table 3 of §503.13 Cadmium mg/kg EPA
6010B/3051
Arsenic 75 41 Copper mg/kg EPA
6010B/3051
Cadmium 85 39 Lead mg/kg EPA
6010B/3051
Copper 4,300 1,500 Molybdenum mg/kg EPA
6010B/3051
Lead 840 300 Nickel mg/kg EPA
6010B/3051
Mercury 57 17 Selenium mg/kg EPA
6010B/3051
Molybdenum 75 - Zinc mg/kg EPA
6010B/3051
Nickel 420 420 Physical Contaminates
% TMECC
Selenium 100 36 Sharps % TMECC
Zinc 7,500 2,800
pH s.u EPA 9045D
Pathogen Ceiling Concentration
Biological Stability VS/S/NS TMECC 05.08B
Fecal Coliform 1000 MPN/g
Fecal Coliform MPN/g EPA9221E
Hydrocarbon Ceiling Concentration
Salmonella MPN/g EPA 1682
Diesel Range Organics
Nitrogen Content: Nitrate/Nitrite-N
mg/kg EPA 45000-
NO3F
(C12-C24) 2000
Total Kjedahl Nitrogen
mg/kg EPA 4500-Norg
C
Heavy Oil Range (>C24
2017 Excellence Award Compost System Navy Whidbey Recycle
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3.4 Recordkeeping §503.17 contains requirements for recordkeeping for classification of biosolids, the least stringent being EQ, Class A biosolids. The rule specifically requires preparers of EQ, Class A biosolids to develop and retain the following information for five years: • The concentrations of pollutants listed in Table 2-1, • A certification statement defined in §503.17(a)(ii), • A description of how the Class A pathogen reduction requirements are met, and • A description of how one of the selected VAR requirements is met 3.5 Odor Mitigation
The Key to controlling odor with the in-vessel composting system is proper management
and maintenance of the biofilter for the system. The biofilter contains 10% of the old
medium which acts like a sponge, absorbing odorous compounds in the exhaust air.
Wood chips provide porosity for even airflow through the biofilter. The biofilter
temperature is monitored by the compost computer control system. The biofilter media
is thoroughly checked daily to make sure it is functioning within parameters. Each year
the biofilter medium is replaced with 10% of the old medium mixed with freshly ground
woodchips to start activation.
Biofilter
Solid Waste Permit Air Permit
2017 Excellence Award Compost System Navy Whidbey Recycle
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3.6. Regulatory Citations No citations received. 4. Worker Health & Safety
4.1 Training
Each compost operator has been through compost facility operator training consisting of
classroom training, hands on interactive sessions, field trips, and a written examination
facilitated by the Washington Organic Recycling Council. Each employee that performs
work at the compost facility reviews the Plan of Operations annually and all training is
documented.
4.2 Safety Procedure and Enforcement
The safety of our people is paramount. Our safety culture includes an energetic,
proactive Safety and Occupational Health program and integrated operational risk
management (ORM). Our safety culture reflects the value we place on taking care of
each other to ensure we remain safe every day. Our daily muster includes safety
discussions where employees are encouraged to discuss safety issues from the previous
day. Non-routine job tasks always involve a safety discussion lead by the team leader or
supervisor along with a weekly impromptu safety talk form the Command Safety
Manager. Formalized monthly safety talks are also a requirement and are recorded in the
on-line Enterprise Safety Applications Management System (ESAMS). We enforce our
safety procedures by using a team approach to safety, guidelines and progressive
corrective action. Specific safety procedures include lock-out/tag-out, use of PPE and
limited site access. Safety procedures are also enforced by having the operator’s manual
available to all operators as their guide to work flow processes. SOPs and operator’s
manual are located onsite for operators to review.
4.3 Injury Rate
There have been no injuries associated with the composting facility because of the
safety measures we have in place.
5. Performance, Economics & Cost-Effectiveness
5.1 Program Success
Diversion percentage, cost avoidance and revenue generated from composting are how
we measure our success. By processing biosolids into compost we avoid the cost of
disposal.
The ISWM program is a non-profit operation where the total cost of the program is
divided by the tons of waste generated to yield a commodity rate in $/ton. This rate
2017 Excellence Award Compost System Navy Whidbey Recycle
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includes the total cost to collect, process and sell commodities to vendors, produce
organic compost, and to collect and dispose of refuse.
Fiscal Year Finished Compost
Revenue
Fiscal Year
Finished Biosolids Cost
Avoidance
13 715 $117,236
13 418 $104,479
14 787 $120,448
14 486 $120,956
15 617 $121,680
15 336 $89,544
16 661 $122,880
16 347 $92,478
5.2 How much downtime does the system have, how long is each instance on average
and what measures have you taken to reduce downtime?
Downtime occurs when preventative maintenance is scheduled. When a vessel is
cleaned it is down for 24 hour. If additional maintenance is required there is no impact
on operations due to the amount of vessels on site. The composting process is a
continuous cycle.
5.3 How does your organization foster customer service? How do you determine
whether you are doing a good job in responding to customer concerns?
Customer service is a vital part of our outreach and education. Our compost operation
has two main customers, base commands and facilities and Navy housing residents.
Our goal is to reduce contamination which is essential to the success of the recycling and
composting program.
5.4 Qualified Recycling Program (QRP)
As a qualified recycling program (QRP) revenue collected from the sale of compost and
other recyclable commodities is used to offset regional program costs or to procure
materials and equipment needed to sustain or improve the program.
5.5 Distribution Food and Yard compost we sell after thorough testing. Biosolid compost is used exclusively for on base beautification projects.
Cliffside RV Park Cliffside RV Park
2017 Excellence Award Compost System Navy Whidbey Recycle
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6. Public Acceptance, Appearance and Aesthetics
6.1 Public Acceptance
Our public relations is focused toward supporting the commands and Navy housing
residents at NAS Whidbey Island which is essential to the success of the recycling and
composting program.
6.2 Outreach and Education
Education and outreach are the key elements of the program that motivate our
community to reduce, reuse and recycle. NWR strives to build a strong sense of
community throughout departments and commands at NAS Whidbey and in the local
community. We encourage all individuals to recognize the benefits of recycling and
contribute to the recycling effort. All aspects of base activities from major construction
projects to family based youth activities are supported by NWR to establish a culture of
recycling, source reduction and reutilization.
NWR staff act as liaisons to Green Teams, base departments and commands to establish
a program for recycling education, performance monitoring and feedback. A network of
command representatives are involved with NWR staff in an effort to promote and
increase recycling within their division. Navy Whidbey Recycle maintains a year round
calendar of educational events and outreach programs that help our patrons apply
recycling practices in their daily lives.
6.3 Aesthetics
Facility maintenance and cleanliness is valued and honored by all NWR staff. Visitors to
the facility constantly comment on the cleanliness and appearance of the recycle
warehouse and compost facility. Interior and exterior cleaning of the facility is done on a
continuous basis by the NWR staff in order to maintain a sanitary and safe environment
for both employees and customers. Equipment and building maintenance is provided by
Base Operations Support Contract (BOSC) on a scheduled or call in basis. Facility
deficiencies are either corrected by the staff or submitted to the BOSC for correction. A
special project performed by the staff included planting flowers using our compost
material to make the facility more aesthetically appealing and promote the benefits of
composting.
2017 Excellence Award Compost System Navy Whidbey Recycle
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NWR vehicle and equipment operators are responsible for the cleanliness of their
equipment. Trucks are pressure washed weekly at the transportation depot in an
environmentally compliant wash rack or spot cleaned using the on board pressure
washer on the compost mixer. The pressure washer on the compost mixer is also used to
clean totes use for compost collection. Dirty water, paper and food waste is dumped
into the compost mixer truck and is added to the compost feed stock thus reducing what
goes to landfills.
7.1 Looking to the Future
NAS Whidbey is expanding and we will also see an expansion in our compost operations.
The base replaced its EA-6B Prowler jets with the EA-18G Growlers and now has 9 carrier
based squadrons. The 3 squadrons of P-3C Orions will be replaced with 6 squadrons of the
P-8A Poseidons. In 2016, the total number of military and civilians on base was 18,240.
Using 2016 as a baseline, the number of personnel associated with NAS Whidbey Island is
projected to increase by 1,320 people, or 7 percent, to 19,560 by 2018 and by 3,740 people,
or 20 percent, to 21,980 by 2019. This number does not include the estimated 20,000 family
members that will accompany military personnel.