10160 - Justman Farm O & M Manual - 20241008
Larson & Associates
surveyors, engineers and planners
9027 Pacific Avenue, Suite 4
Tacoma, WA 98444
OPERATION AND MAINTENANCE MANUAL
PROPONENT:
C&E DEVELOPMENTS, LLC
P.O. BOX 2983
YELM, WA 98597
CONTACT: ERIC PETERSON
PHONE: (253) 278-0343
PREPARED BY:
Larson & Associates
surveyors, engineers and planners
9027 Pacific Avenue, Suite 4
Tacoma, WA 98444
(253) 474-3404
October 8, 2024
Page 1 of 17
SECTION 1 – PROPOSED PROJECT DESCRIPTION ................................................................... 1
SECTION 2 – MAINTENANCE IMPORTANCE AND INTENT .......................................................... 1-2
SECTION 3 – RESPONSIBLE PARTIES ................................................................................................... 2
SECTION 4 – FACILITIES REQUIRING MAINTENANCE .................................................................... 2
SECTION 5 – MAINTENANCE INSTRUCTIONS ...................................................................... 2-3
SECTION 6 - VEGETATION MAINTENANCE ........................................................................................ 3
SECTION 7 - POLLUTION SOURCE CONTROL MEASURES ........................................................... 3-4
SECTION 8 - ANNUAL COST OF MAINTENANCE ............................................................................... 4
APPENDIX A – STORM FACILITIES MAINTENANCE BMPS ......................................................... A-1
APPENDIX B – POLLUTION SOURCE CONTROL BMPS................................................................. B-1
Page 2 of 17
SECTION 1 - PROPOSED PROJECT DESCRIPTION
The proposed JUSTMAN FARM is located in Section 29, Township 17 North, Range 2 East of
the Willamette Meridian in Yelm, Washington. Parcel number is TPN 64303200600, the area of
the lot is 9.37 ac., and address is 16731 State Route 507 SE Yelm, WA 98597. The project consists
of providing a landscaping wall and grading the site.
Stormwater runoff generated from pervious surfaces will be collected and conveyed to an
infiltration pond for infiltration. All created landscaped areas will receive compost amended
topsoil in accordance with BMP T5.13, Chapter V-12, Volume V of the SWMMWW. Due to
converting more than 2.5 acres of native vegetation to pasture, it is necessary to address all
Minimum Requirements for this project.
SECTION 2 – MAINTENANCE IMPORATANCE AND INTENT
The importance of maintenance of the proper functioning of stormwater control facilities cannot
be over-emphasized. A substantial portion of failures (clogging of filters, resuspension of
sediments, loss of storage capacity, etc.) are due to inadequate maintenance. Stormwater BMP
maintenance is essential to ensure that BMPs function as intended throughout their full life cycle
The fundamentals goals of maintenance activities are to ensure the entire flow regime and
treatment train designed for this site continue to fully function. For this site these include:
• Maintain designed stormwater infiltration capacity
• Maintain ability of storm facility to attenuate flow rates
• Maintain ability of safely convey design stormwater flows
• Maintain ability to treat stormwater runoff quality
• Preserve soil and plant health, as well as stormwater flow contact with plant and soil
systems
• Clearly identify systems so they can be protected
• Keep maintenance costs low
• Prevent large-scale or expensive stormwater system failures
The intent of this section and manual is to pass on to the responsible party(s) all the information
critical to understand the design of the system, risks and considerations for proper use, suggestions
for maintenance frequencies, and cost so that realistic budgets can be established.
Page 3 of 17
SECTION 3 – RESPONSIBLE PARTIES
The party responsible for maintenance and operation of all stormwater structures and BMPs
requiring maintenance for the proposed development is:
C&E DEVELOPMENTS, LLC
P.O. BOX 2983
YELM, WA 98597
CONTACT: ERIC PETERSON
PHONE: (253) 278-0343
SECTION 4 – FACILITIES REQUIRING MAINTENANCE
There is one (1) primary stormwater BMP for managing the project’s stormwater runoff for an
infiltration pond for flow control of onsite runoff. A brief description of the BMP is provided in
the next section; maintenance items and checklists for this facility is provided in Appendix “A”.
SECTION 5 – MAINTENANCE INSTRUCTIONS
INFILTRATION POND: Runoff from a significant portion of the pervious area of the site will
sheet flow to an infiltration pond at the north portion of the property. The pond is designed to
infiltrate the runoff into the highly permeable native soil under the pond. An emergency overflow
spillway located on the pond’s north berm is designed to release runoff in the rare event the pond
reaches capacity. Regular removal of the particulate pollutants, i.e. – sediment, and other debris
and trash from the pond is important to the proper function of the infiltration pond. Typical
maintenance items are provided in detail in Appendix “A” and include regular removal of
sediment, trash, debris, poisonous vegetation and noxious weeds, erosion of side slopes, and repair
of pipe inlet rip rap pads or the emergency overflow spillway.
SECTION 6 – VEGETATION MAINTENANCE
Compost amended soils conforming to BMP T5.13 will be applied to all cleared areas.
SECTION 7 – POLLUTION SOURCE CONTROL MEASURES
Pollution source control is the application of pollution prevention practices (BMPs) on a developed
site which reduces contamination of stormwater runoff at the source. In Volume IV of the
SWMMWW, Department of Ecology describes pollution source control as the application of
operational source control BMPs and structural source control BMPs. As a future commercial and
construction yard development applicable (i.e. – mandatory) operational source control BMPs
include:
• Formation of a pollution prevention team
• Good housekeeping practices
• Preventive maintenance procedures
• Spill prevention and cleanup
• Employee training
• Regular inspections
• Record Keeping Page 4 of 17
Detailed information of the following applicable structural source control BMPs are provided in
Appendix B:
• S411 – BMPs for Landscaping and Lawn/Vegetation Management
• S417 – BMPs for Maintenance of Stormwater Drainage and Treatment Systems
SECTION 8 – ANNUAL COST OF MAINTENANCE
It is expected the party listed in Section 3 above will be responsible for maintaining all storm
drainage facilities and implementing pollution source control measures for all uses on the property.
The expected annual maintenance cost for the storm drainage facilities is estimated to be $1,000
to $2,000.
END OF REPORT
Page 5 of 17
APPENDIX “A”
STORM FACILITIES MAINTENANCE BMPs
Page 6 of 17
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Page 9 of 17
APPENDIX “B”
STRUCTURAL SOURCE CONTROL BMPs FOR
CONSTRUCTION AND COMMERCIAL USES
Page 10 of 17
that can cause air pollution include grain dust, sawdust, coal, gravel, crushed rock, cement, and
boiler fly ash. Air emissions can contaminate stormwater. The objective of this BMP is to reduce
the stormwater pollutants caused by dust generation and control.
Pollutant Control Approach: Prevent dust generation and emissions where feasible, regularly
clean-up dust that can contaminate stormwater, and convey dust contaminated stormwater to
proper treatment.
Applicable BMPs:
z Clean, as needed, powder material handling equipment and vehicles.
z Regularly sweep dust accumulation areas that can contaminate stormwater. Conduct
sweeping using vacuum filter equipment to minimize dust generation and to ensure optimal
dust removal.
z Use dust filtration/collection systems such as baghouse filters, cyclone separators, etc. to
control vented dust emissions that could contaminate stormwater. Control of zinc dusts in
rubber production is one example.
z Maintain on-site controls to prevent vehicle track-out.
z Maintain dust collection devices on a regular basis.
Recommended BMPs:
z In manufacturing operations, train employees to handle powders carefully to prevent gen-
eration of dust.
z Use water spray to flush dust accumulations to sanitary sewers where allowed by the local
sewer authority or to other appropriate treatment system.
z Use approved dust suppressants such as those listed in Methods for Dust Control (Eco-
logy, 2016b). Application of some products may not be appropriate in close proximity to
receiving waters or conveyances close to receiving waters. For more information, check
with Ecology or the local jurisdiction.
Recommended Treatment BMPs
Install sedimentation basins, wetponds, wetvaults, catch basin filters, vegetated filter strips, or
equivalent sediment removal BMPs.
S411 BMPs for Landscaping and Lawn / Vegetation
Management
Description of Pollutant Sources: Landscaping can include grading, soil transfer, vegetation
planting, and vegetation removal. Examples include weed control on golf course lawns, access
roads, and utility corridors and during landscaping; and residential lawn/plant care. Proper man-
agement of vegetation can minimize excess nutrients and pesticides.
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Volume IV - Chapter 4 - Page 573
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Pollutant Control Approach: Maintain appropriate vegetation to control erosion and the dis-
charge of stormwater pollutants. Prevent debris contamination of stormwater. Where practicable,
grow plant species appropriate for the site, or adjust the soil properties of the site to grow desired
plant species.
Applicable BMPs:
z Install engineered soil/landscape systems to improve the infiltration and regulation of storm-
water in landscaped areas.
z Select the right plants for the planting location based on proposed use, available main-
tenance, soil conditions, sun exposure, water availability, height, sight factors, and space
available.
z Ensure that plants selected for planting are not on the noxious weed list. For example, but-
terfly bush often gets planted as an ornamental but is actually on the noxious weed list.
The Washington State Noxious Weed List can be found at the following webpage:
https://www.nwcb.wa.gov/printable-noxious-weed-list
z Do not dispose of collected vegetation into waterways or storm sewer systems.
z Do not blow vegetation or other debris into the drainage system.
z Dispose of collected vegetation such as grass clippings, leaves, sticks by composting or
recycling.
z Remove, bag, and dispose of class A and B noxious weeds in the garbage immediately.
z Do not compost noxious weeds as it may lead to spreading through seed or fragment if the
composting process is not hot enough.
z Use manual and/or mechanical methods of vegetation removal (pincer-type weeding tools,
flame weeders, or hot water weeders as appropriate) rather than applying herbicides,
where practical.
z Use at least an 8 inch "topsoil" layer with at least 8% organic matter to provide a sufficient
vegetation-growing medium.
o Organic matter is the least water-soluble form of nutrients that can be added to the
soil. Composted organic matter generally releases only between 2% and 10% of its
total nitrogen annually, and this release corresponds closely to the plant growth
cycle. Return natural plant debris and mulch to the soil, to continue recycling nutri-
ents indefinitely.
z Select the appropriate turfgrass mixture for the climate and soil type.
o Certain tall fescues and rye grasses resist insect attack because the symbiotic endo-
phytic fungi found naturally in their tissues repel or kill common leaf and stem-eating
lawn insects.
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Page 12 of 17
The fungus causes no known adverse effects to the host plant or to humans.
Tall fescues and rye grasses do not repel root-feeding lawn pests such as
Crane Fly larvae.
Tall fescues and rye grasses are toxic to ruminants such as cattle and sheep
o Endophytic grasses are commercially available; use them in areas such as parks or
golf courses where grazing does not occur.
o Local agricultural or gardening resources such as the Washington State University
Extension office can offer advice on which types of grass are best suited to the area
and soil type.
z Use the following seeding and planting BMPs, or equivalent BMPs, to obtain information on
grass mixtures, temporary and permanent seeding procedures, maintenance of a recently
planted area, and fertilizer application rates:
o BMP C120: Temporary and Permanent Seeding
o BMP C121: Mulching
o BMP C123: Plastic Covering
o BMP C124: Sodding
z Adjusting the soil properties of the subject site can assist in selection of desired plant spe-
cies. Consult a soil restoration specialist for site-specific conditions.
Recommended Additional BMPs:
z Conduct mulch-mowing whenever practicable.
z Use native plants in landscaping. Native plants do not require extensive fertilizer or pesti-
cide applications. Native plants may also require less watering.
z Use mulch or other erosion control measures on soils exposed for more than:
o one week during the dry season (May 1 to September 30), or
o 2 days during the wet season (October 1 to April 30).
z Till a topsoil mix or composted organic material into the soil to create a well-mixed transition
layer that encourages deeper root systems and drought-resistant plants.
z Apply an annual topdressing application of 3/8 inches of compost. Amending existing land-
scapes and turf systems by increasing the percentage of organic matter and depth of top-
soil can:
o Substantially improve the permeability of the soil.
o Increase the disease and drought resistance of the vegetation.
o Reduce the demand for fertilizers and pesticides.
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Volume IV - Chapter 4 - Page 575
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z Disinfect gardening tools after pruning diseased plants to prevent the spread of disease.
z Prune trees and shrubs in a manner appropriate for each species.
z If specific plants have a high mortality rate, assess the cause and replace with another
more appropriate species.
z When working around and below mature trees, follow the most current American National
Standards Institute (ANSI) ANSI A300 standards (see http://www.t-
cia.org/TCIA/BUSINESS/ANSI_A300_Standards_/TCIA/BUSINESS/A300_Stand-
ards/A300_Standards.aspx?hkey=202ff566-4364-4686-b7c1-2a365af59669) and
International Society of Arboriculture (ISA) BMPs to the extent practicable (e.g. take care to
minimize any damage to tree roots and avoid compaction of soil).
z Monitor tree support systems (stakes, guys, etc.).
o Repair and adjust as needed to provide support and prevent tree damage.
o Remove tree supports after one growing season or maximum of 1 year.
o Backfill stake holes after removal.
z When continued, regular pruning (more than one time during the growing season) is
required to maintain visual sight lines for safety or clearance along a walk or drive, consider
relocating the plant to a more appropriate location.
z Make reasonable attempts to remove and dispose of class C noxious weeds.
z Re-seed bare turf areas until the vegetation fully covers the ground surface.
z Watch for and respond to new occurrences of especially aggressive weeds such as Him-
alayan blackberry, Japanese knotweed, morning glory, English ivy, and reed canary grass
to avoid invasions.
z Plant and protect trees per BMP T5.16: Tree Retention and Tree Planting.
z Aerate lawns regularly in areas of heavy use where the soil tends to become compacted.
Conduct aeration while the grasses in the lawn are growing most vigorously. Remove lay-
ers of thatch greater than ¾-inch deep.
z Set the mowing height at the highest acceptable level and mow at times and intervals
designed to minimize stress on the turf. Generally mowing only 1/3 of the grass blade
height will prevent stressing the turf.
o Mowing is a stress-creating activity for turfgrass.
o Grass decreases its productivity when mowed too short and there is less growth of
roots and rhizomes. The turf becomes less tolerant of environmental stresses, more
disease prone and more reliant on outside means such as pesticides, fertilizers, and
irrigation to remain healthy.
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Additional BMP Information:
z King County's Best Management Practices for Golf Course Development and Operation
(King County, 1993) has additional BMPs for Turfgrass Maintenance and Operation.
z King County, Seattle Public Utilities, and the Saving Water Partnership have created the fol-
lowing natural lawn and garden care resources that include guidance on building healthy
soil with compost and mulch, selecting appropriate plants, watering, using alternatives to
pesticides, and implementing natural lawn care techniques.
Natural Yard Care - Five steps to make your piece of the planet a healthier place to
live (King County and SPU, 2008)
The Natural Lawn & Garden Series: Smart Watering (Saving Water Partnership,
2006)
Natural Lawn Care for Western Washington (Saving Water Partnership, 2007)
The Natural Lawn & Garden Series: Growing Healthy Soil; Choosing the Right
Plants; and Natural Pest, Weed and Disease Control (Saving Water Partnership,
2012)
z The International Society of Arboriculture (ISA) is a group that promotes the professional
practice of arboriculture and fosters a greater worldwide awareness of the benefits of trees
through research, technology, and education. ISA standards used for managing trees,
shrubs, and other woody plants are the American National Standards Institute (ANSI) A300
standards. The ANSI A300 standards are voluntary industry consensus standards
developed by the Tree Care Industry Association (TCIA) and written by the Accredited
Standards Committee (ASC). The ANSI standards can be found on the ISA website:
www.isa-arbor.com/education/publications/index.aspx
z Washington State University's Gardening in Washington State website at http://garden-
ing.wsu.edu contains Washington State specific information about vegetation management
based on the type of landscape.
z See the Pacific Northwest Plant Disease Management Handbook (Pscheidt and Ocamb,
2016) for information on disease recognition and for additional resources.
S425 BMPs for Soil Erosion and Sediment Control
at Industrial Sites
Description of Pollutant Sources: Industrial activities on soil areas, exposed and disturbed
soils, steep grading, etc. can be sources of sediments that can contaminate stormwater runoff.
Pollutant Control Approach: Limit the exposure of erodible soil, stabilize, or cover erodible soil
where necessary to prevent erosion, and/or provide treatment for stormwater contaminated with
TSS caused by eroded soil.
2024 Stormwater Management Manual for Western Washington
Volume IV - Chapter 4 - Page 577
Page 15 of 17
S417 BMPs for Maintenance of Stormwater
Drainage Systems and Stormwater Management
BMPs
Description of Pollutant Sources: Facilities include roadside catch basins on arterials and
within residential areas, stormwater conveyance systems, detention BMPs such as ponds and
vaults, oil/water separators, biofilters, settling basins, infiltration systems, and all other types of
stormwater management BMPs presented in Volume V. Oil and grease, hydrocarbons, debris,
heavy metals, sediments, and contaminated water are found in catch basins, oil and water sep-
arators, settling basins, etc.
Pollutant Control Approach: Provide maintenance and cleaning of debris, sediments, and other
pollutants from stormwater collection, conveyance, and Runoff Treatment and Flow Control BMPs
to maintain proper operation.
Applicable Operational BMPs:
Maintain stormwater management BMPs per the operations and maintenance (O&M) procedures
presented in Appendix V-A: BMP Maintenance Tables, in addition to the following BMPs:
z Inspect and clean stormwater management BMPs, conveyance systems, and catch basins
as needed, and determine necessary O&M improvements.
z Promptly repair any deterioration threatening the structural integrity of stormwater facilities.
These include replacement of clean-out gates, catch basin lids, and rock in emergency spill-
ways.
z Ensure adequacy of storm sewer capacities and prevent heavy sediment discharges to the
sewer system.
z Regularly remove debris and sludge from BMPs used for peak-rate control, treatment, etc.
and discharge to a sanitary sewer if approved by the sewer authority, or truck to an appro-
priate local or state government approved disposal site.
z Clean catch basins when the depth of deposits reaches 60 percent of the sump depth as
measured from the bottom of basin to the invert of the lowest pipe into or out of the basin.
However, in no case should there be less than six inches clearance from the debris surface
to the invert of the lowest pipe. Some catch basins (for example, WSDOT's Catch Basin
Type 1L (WSDOT, 2011b)) may have as little as 12 inches sediment storage below the
invert. These catch basins need frequent inspection and cleaning to prevent scouring.
Where these catch basins are part of a stormwater collection and treatment system, the sys-
tem owner/operator may choose to concentrate maintenance efforts on downstream con-
trol devices as part of a systems approach.
z Properly dispose of all solids, polluted material, and stagnant water collected through sys-
tem cleaning. Do not decant water back into the drainage system from eductor trucks or
vacuum equipment since there may be residual contaminants in the cleaning equipment.
Do not jet material downstream into the public drainage system.
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Page 16 of 17
z Clean woody debris in a catch basin as frequently as needed to ensure proper operation of
the catch basin.
z Post warning signs; “Dump No Waste - Drains to Groundwater,” “Streams,” “Lakes,” or
emboss on or adjacent to all storm drain inlets where possible. See S442 BMPs for Label-
ing Storm Drain Inlets On Your Property.
z Disposal of sediments and liquids from the catch basins must comply with Appendix IV-B:
Management of Street Waste Solids and Liquids.
S421 BMPs for Parking and Storage of Vehicles
and Equipment
Description of Pollutant Sources: Public and commercial parking lots such as retail store, fleet
vehicle (including rent-a-car lots and car dealerships), equipment sale and rental parking lots, and
parking lot driveways, can be sources of toxic hydrocarbons and other organic compounds, includ-
ing oils and greases, metals, and suspended solids.
Pollutant Control Approach: If the parking lot meets the site use thresholds used to determine if
the site is expected to generate high concentrations of oil, as defined in Step 2: Determine if an Oil
Control BMP is Required in III-1.2 Choosing Your Runoff Treatment BMPs, provide oil removal
equipment for the contaminated stormwater runoff.
Applicable Operational BMPs:
z If a parking lot must be washed, discharge the washwater to a sanitary sewer, if allowed by
the local sewer authority, or other approved wastewater treatment system, or collect wash-
water for off-site disposal.
z Do not hose down the area to a storm sewer or receiving water. Vacuum sweep parking
lots, storage areas, and driveways regularly to collect dirt, waste, and debris. Mechanical or
hand sweeping may be necessary for areas where a vacuum sweeper cannot reach.
z Clean up vehicle and equipment fluid drips and spills immediately.
z Place drip pans below leaking vehicles (including inoperative vehicles and equipment) in a
manner that catches leaks or spills, including employee vehicles. Drip pans must be man-
aged to prevent overfilling and the contents disposed of properly.
Recommended Operational BMPs:
z Encourage employees to repair leaking personal vehicles.
z Encourage employees to carpool or use public transit through incentives.
z Encourage customers to use public transit by rewarding valid transit pass holders with dis-
counts.
z Install catch basin inserts to collect excess sediment and oil if necessary. Inspect and main-
tain catch basin inserts to ensure they are working correctly.
2024 Stormwater Management Manual for Western Washington
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