Septic in Windsor, SC

Last updated: Mar 21, 2026

In Windsor, you'll notice that many homes sit among friendly neighborly yards and rely on a practical, on-site wastewater system rather than a centralized sewer line. Is septic common in Windsor? Yes—it's a standard setup for a large part of the community, especially in areas where public sewer service isn't available or cost-effective to extend. If you own or are buying a Windsor home, you should expect a septic system unless the property is connected to town sewer. A quick check with the current owner or listing broker about the system type, its age, and pumping history can save you surprises down the road.

Why Windsor homes typically use septic systems

Windsor's layout and history have shaped how wastewater is managed. Many neighborhoods developed before municipally managed sewer lines reached every street, and extending sewer service can be costly and disruptive. On-site septic offers a practical, relatively affordable way to treat wastewater right on the property. Local soil conditions and groundwater patterns also influence system design—most properties rely on a conventional tank and drain field, while some with challenging soils or high water tables may use enhanced designs like mound systems. In short, a well-planned septic system fits the way Windsor is built and lived in: private, efficient, and responsive to the land.

High-level explanation of why septic exists here

A modern septic system treats household wastewater on-site, using natural processes to separate solids from liquids. Wastewater flows into a septic tank, where solids settle into a sludge layer and lighter fats and scum rise to the top. The clarified liquid then moves into a drain field where the soil itself acts as a filter, removing many contaminants before the water re-enters the ground. In Windsor, the success of this approach depends on the right combination of tank size, drainage bed design, and soil characteristics. When soils drain well and the groundwater seasonally cooperates, gravity-fed drain fields work reliably. When conditions aren't ideal, a licensed pro may design an alternative that still protects the property and the environment.

Helpful reminders as a Windsor homeowner

  • If you're buying, request a septic inspection and a record of past pumping, repairs, and the tank's age.
  • Typical maintenance: plan to pump every 3–5 years for a standard family, but follow the tank size and usage guidance from a licensed inspector.
  • Protect the system: conserve water, avoid dumping grease or chemicals down drains, and keep vehicles off parts of the drain field.
  • Watch for signs of trouble: standing water over the drain field, gurgling sounds in plumbing, back-ups, or unusually lush grass over the drain area.

A practical, neighborly note: we're here to help you navigate Windsor septic with clear, trusted guidance as you maintain a safe, well-functioning system. Below are steps and local considerations to get you started.

Where Septic Systems Are Common in Windsor

Map of septic coverage in Windsor, SC

Common Windsor Areas for Septic

In Windsor, septic systems are most common in rural and semi-rural parts of town. You'll see them where centralized sewer lines don't reach or aren't cost-effective to extend. Typical settings include:

  • Rural residential parcels along county roads and fringe neighborhoods outside the town center.
  • Farms and agricultural properties with residences and outbuildings.
  • Older subdivisions that were developed before municipal sewer was installed.
  • Properties with soil or groundwater conditions that make piped sewer impractical without expensive engineering.

Why Windsor Relies on Septic

Septic use in Windsor is driven by practical, local realities:

  • Infrastructure and cost: Extending sewer lines to low-density, scattered parcels is expensive. Private septic often remains the most economical option for homeowners and developers outside the core town area.
  • Historical development: Much of Windsor's housing stock predates modern sewer expansion, so septic systems became the standard by default.
  • Soil and drainage: Windsor-area soils are a mix—some locations drain well and support traditional septic fields, while others require engineered solutions or alternative systems due to poor drainage or a high water table.
  • Regulation and maintenance: South Carolina requires permitting and regular inspections for septic systems, which helps ensure long-term reliability in areas that rely on on-site wastewater treatment. See official resources for details on rules and best practices.

Typical System Types You Might See in Windsor

  • Conventional septic system: A well-established setup with a septic tank and a drain field.
  • Mound system: Used where soils are shallow or have limited drainage; the system creates an elevated drain field to permit wastewater treatment.
  • Alternative/engineered systems: For challenging soils or high performance needs (ventilation, odor control, or frequent use), specialized designs may be installed.
  • Shared or cluster systems: In some larger parcels or tightly spaced developments outside sewered areas, multiple homes may share a single treatment and disposal installation managed by a single permit.

Quick Checks to Identify a Windsor Property's Septic Status

  1. Look for a yard lid or access cover that marks the septic tank; it's often near the side or back edge of the yard.
  2. Check property documents (deed, plat, or tax assessor notes) for septic or well permits.
  3. Contact a licensed septic contractor or the South Carolina Department of Health and Environmental Control (DHEC) to locate and inspect the system.
  4. If you're buying a home, request recent maintenance records and a formal septic inspection as part of the due-diligence process.

Official Resources

  • SC DHEC Onsite Sewage Systems:
  • EPA Septic Systems overview:

Septic vs Sewer: What Homeowners in Windsor Should Know

Quick comparison

  • Sewer connection: Your home taps into a municipal wastewater system. The city or county handles treatment, maintenance, and line repairs. You pay a monthly sewer bill based on usage.
  • Septic system: The home uses a private onsite system. The homeowner is responsible for installation, regular maintenance, pumping, and repairs. Costs are upfront with ongoing care.

How a septic system works

A typical onsite system has three main parts:

  • Septic tank: Wastewater enters here, solids settle to the bottom, and scum floats to the top.
  • Leach or drain field: Cleansed water from the tank is distributed into the soil through a network of pipes.
  • Soil and microbes: The soil and natural bacteria break down remaining contaminants before water re-enters groundwater.

Maintenance reality:

  • Regular pumping removes accumulated solids that could clog the system.
  • The soil's absorption capacity is finite; improper use can shorten its life.

Pros and cons for Windsor homeowners

  • Sewer pros:
    • No home pumping or tank maintenance required.
    • Fewer worries about seasonal groundwater or soil conditions.
  • Sewer cons:
    • Ongoing monthly or quarterly bills, sometimes unpredictable with usage.
    • Backups or city-wide issues can affect many homes at once.
  • Septic pros:
    • Potentially lower long-term costs if the system is well cared for.
    • Independence from municipal outages and sewer surcharges.
  • Septic cons:
    • Responsibility for pumping, inspections, and repairs falls on the homeowner.
    • Poor maintenance or improper waste disposal accelerates failures and costly repairs.

Cost considerations in Windsor

  • Septic installation and start-up: Typically several thousand to tens of thousands of dollars, depending on soil, tank size, and permits.
  • Septic ongoing maintenance: Pumping every 3–5 years is common, with inspections in between; costs vary by region and contractor.
  • Sewer connection and use: Tap fees, hookup costs, and monthly sewer charges—these depend on the local utility and service area.
  • Long-term view: A well-maintained septic can be economical over decades; a neglected system can lead to expensive replacements and environmental repair.

How to know if you're on septic or sewer

  1. Check your utility bills and property records or tax assessment notices for references to "sewer" or "private septic."
  2. Contact the local utility or the county's zoning or environmental health office to confirm your service type.
  3. Inspect your yard for a septic-related access lid, buried tanks, or a clearly defined leach field (note: don't dig without confirming).
  4. Review your property plat or building permit history for sewer connection details.

Maintenance basics you can implement today

  • Use water efficiently: fix leaks, install low-flow fixtures, and spread out laundry and dishwashing.
  • Be careful what you flush or pour: fats, oils, chemicals, paints, wipes, and medications can damage systems.
  • Schedule regular inspections: homeowner inspections plus professional evaluations every 1–3 years help catch issues early.
  • Protect the drain field: avoid parking or heavy equipment on the area; preserve tree roots away from lines.
  • Plan for pumping: establish a proactive pumping schedule based on tank size and household use.

When to call a pro

  • Slow drains, gurgling sounds, or frequent backups.
  • Sewage odors in the yard or home.
  • Standing water or damp, spongy areas over the drain field.
  • Deposits of settled solids near the tank access lid or a sudden drop in system performance.

Official guidance and resources

  • EPA septic systems overview and maintenance tips:

Typical Septic System Types in Windsor

Conventional gravity septic systems

  • How they work: Wastewater flows by gravity from the home into a septic tank, where solids settle, then liquid effluent drains by gravity into a trench or bed in the leach field.
  • When you'll see them: Still the most common on homes with well-drained soils and adequate space for a drainfield.
  • Pros: Simple design, generally lower upfront cost, easy to service if soil is right.
  • Cons: Performance hinges on soil permeability and proper drainfield size; high water tables or heavy clay can limit effectiveness.
  • Maintenance notes: Regular pumping (every 3–5 years for typical households) and annual inspections help catch issues before failures.

Pressure distribution systems

  • How they work: A pump moves effluent from the tank to multiple points in the drainfield, distributing wastewater evenly across the site.
  • When you'll see them: Useful on sloped lots, narrow lots, or soils with uneven absorption.
  • Pros: More uniform loading of the drainfield, better performance in challenging soils.
  • Cons: More components to maintain (pump, lines, control panel); higher cost than conventional gravity.
  • Maintenance notes: Check pumps and alarms, schedule professional service, and ensure electrical connections stay dry and reliable.

Mound systems

  • How they work: An elevated "mound" of sand beneath the drainfield sits above poor native soils or a high water table; effluent is treated as it percolates through the mound before reaching the soil.
  • When you'll see them: When site soils are restrictive, water tables rise seasonally, or space for a large conventional field isn't available.
  • Pros: Expands usable lot area by working with shallow or poorly draining soils; can meet stricter setbacks.
  • Cons: More expensive to install and maintain; requires space for the mound and continued monitoring.
  • Maintenance notes: Regular inspections for surface wetness and drainage performance; timely pumping and professional servicing.

Sand filter systems

  • How they work: Effluent from the septic tank passes through a lined bed of sand, which provides an additional treatment step before reaching the drainfield.
  • When you'll see them: In soils with limited permeability or where a conventional drainfield would fail to meet treatment goals.
  • Pros: Higher treatment efficiency in marginal soils; more predictable performance in some conditions.
  • Cons: Requires space, frequent maintenance, and occasional sand replacement or media care.
  • Maintenance notes: Routine servicing, filter checks, and annual inspections to verify flow and permits are in order.

Aerobic Treatment Units (ATUs)

  • How they work: An ATU adds controlled aerobic (oxygen-rich) treatment to the wastewater before it enters the drainfield, producing cleaner effluent.
  • When you'll see them: On properties with limited space, poor soils, or where higher levels of treatment are desired.
  • Pros: Superior effluent quality, often allows smaller or more flexible drainfields; faster restoration after heavy use.
  • Cons: Higher ongoing energy use, more frequent professional service contracts, and dependence on power.
  • Maintenance notes: Regular servicing by a licensed operator; periodic inspections and effluent testing as required by local codes.

Drip irrigation and other advanced disposal methods

  • How they work: Small-diameter lines deliver treated effluent to shallow soil zones or landscapes, maximizing efficiency in tight spaces.
  • When you'll see them: In yards with limited usable area or a desire to recycle landscape water; not universally permitted in every Windsor property.
  • Pros: Minimal surface footprint; precise moisture delivery for landscaping.
  • Cons: More specialized installation and maintenance; requires professional design and routine checks.
  • Maintenance notes: Ensure proper filtration, emitter verification, and annual system checks.

General Windsor considerations

  • Site constraints: Windsor soils and groundwater patterns influence which systems are viable. Local codes may favor or restrict certain technologies based on soil tests and water-table expectations.
  • Permits and inspections: Any system choice should align with South Carolina DHEC guidelines and your county health department requirements.
  • By-the-book maintenance: Keep a simple schedule—pump, inspect, and service per your system type and local recommendations.

Resources

  • EPA Septic Systems:

Common Septic Issues in Windsor

Windsor-specific soil and water considerations

  • Soil variability: Windsor-area soils can range from compacted clay to looser, sandy pockets. Dense clay slows infiltration, while sandy spots can leach effluent more quickly, potentially stressing the drainfield if not properly sized.
  • Water table and rainfall: Heavy rains and high water tables can saturate drainfields, leading to backups or surface wet spots. Seasonal flooding or persistent damp soils amplify the risk.
  • Drainage patterns: Yard grading, downspouts, and irrigation near the septic area can overwhelm the system. Proper separation from driveways, sheds, and garden beds helps maintain drainage.
  • Regulatory setbacks: Local rules in Windsor (and SC-wide) dictate setbacks from wells, property lines, and water bodies. Always follow South Carolina DHEC guidelines for safe siting and maintenance.

Common septic issues seen in Windsor homes

  • Drainfield saturation and backups: Prolonged wet conditions or an undersized field can cause effluent to pool or surface, triggering odors and slow drains.
  • Soil absorption problems: Clay-heavy zones or compacted soils impede effluent percolation, stressing the tank and field.
  • Root intrusion: Trees and ornamental shrubs with invasive roots can crack or clog pipes and drain fields, reducing system performance.
  • Overloading the system: Large families, frequent heavy laundry loads, long showers, and flushing frequent non-biodegradable items increase solids and water volume.
  • Aging components: Tanks past their service life, leach fields nearing capacity, or damaged distribution boxes are more common in Windsor's older homes.
  • Improper waste disposal: Fats, oils, grease, solvents, paints, and chemical cleaners kill beneficial bacteria or accumulate solids, hampering breakdown and flow.
  • Landscaping and drainage disturbances: Grading changes, new irrigation lines, or heavy equipment over the drain field can compact soil or damage pipes.

Signs your Windsor septic is failing

  • Slow drains and frequent clogs throughout the house.
  • Foul odors around the septic tank, leach field, or yard.
  • Patches of lush, green vegetation above the drain field.
  • Surface wet spots, damp soil, or standing water in the yard over or near the septic area.
  • Gurgling sounds in plumbing or sewage backups into sinks or toilets.
  • Bright green, unusually healthy grass over the drain field compared to surrounding areas.

Practical steps to address Windsor septic issues

  1. Conserve water daily
  2. Space out laundry, run full loads, and use low-flow fixtures to reduce input.
  3. Fix dripping faucets and running toilets promptly.
  4. Inspect for leaks and damage
  5. Check for hidden leaks in toilets, irrigation lines, and underground pipes.
  6. Look for cracks or damage on the septic tank lid and risers; keep lids accessible and secured.
  7. Schedule professional pumping and evaluation
  8. Have the tank pumped as recommended (typically every 3–5 years, depending on usage and tank size).
  9. Request a drain-field evaluation, including a percolation test and, if needed, a camera inspection of pipes to detect root intrusion or cracks.
  10. Manage the system with sensible practices
  11. Avoid flushing wipes, diapers, cat litter, chemicals, solvents, paints, or grease.
  12. Use enzyme or bacteria additives only if advised by a licensed professional; most systems function best with regular pumping and proper maintenance rather than additives.
  13. Protect the drain field
  14. Keep heavy equipment, vehicles, and structures off the drain field.
  15. Direct downspouts and irrigation away from the drain field; ensure proper grading to avoid pooling.

Prevention tips tailored to Windsor properties

  • Regular inspections: Have a professional inspect the system annually and pump on schedule.
  • Plant wisely: Choose shallow-rooted plants away from the drain field; avoid trees near lines.
  • Irrigation management: Use irrigation controllers and rain sensors to minimize unnecessary watering.
  • Yard care: Maintain a minimum buffer around the drain field; limit soil compaction and avoid construction near the area.
  • Nutrient control: Apply fertilizer away from the drain field and during appropriate seasons to prevent runoff into the system.

When to call a professional in Windsor

  1. You notice persistent odors, wet spots, or sewage backing up into fixtures.
  2. Drains are slow even after basic clogs are cleared, or you suspect root intrusion.
  3. The system is overdue for pumping or you're planning major landscaping that could affect the drain field.

Official resources

  • EPA: Septic systems information and consumer guidance —
  • South Carolina DHEC: Onsite Sewage Systems guidance and regulations —

Septic Inspection, Permits & Local Oversight

Who regulates septic systems in Windsor, SC

In Windsor (and throughout South Carolina), on-site wastewater systems are regulated at the state level by the Department of Health and Environmental Control (DHEC) through the On-Site Wastewater Program, with local oversight by the county health department and/or building officials. Permits and inspections are typically required for new installations, repairs, or significant alterations. Keeping up with the right approvals helps protect groundwater, wells, and your home's drainage.

When you typically need a permit

  • New septic system installation
  • Replacement of an existing tank or drainfield
  • Major repairs or alterations to the system
  • Expanding a system to serve additional fixtures or a new building
  • Moving, reconfiguring, or changing the use of a property that affects the wastewater system

Permits: how to apply

  1. Hire a licensed septic contractor (required for installation, most repairs, and many alterations in SC).
  2. Schedule a site evaluation and soil assessment if your area requires it.
  3. Submit the permit application through your local county health department (they administer the state OSW program in your county).
  4. Pay the required fees and obtain a permit number.
  5. Have the system plan reviewed and approved; receive the go-ahead to install.
  6. After installation, book a final inspection and obtain the official as-built documentation.

Notes:

  • Localities may have additional requirements or forms, so check with your county health department early in the process.
  • Retain all permit approvals, drawings, and inspection reports in your home records.

What inspectors look for during inspections

  • Proper siting: setbacks from wells, property lines, structures, and drainage ways.
  • Tank accessibility: lids, risers, and safe access for pumping and inspection.
  • Tank integrity and components: correct baffles, proper waste inlets/outlets, and system labeling.
  • Drainage field layout: correct trenching, distribution, and adequate soil absorption.
  • Soil suitability: confirmation that the soil supports adequate effluent treatment.
  • Venting and pump chambers (if present): correct venting, alarms, and power supply.
  • Stormwater and erosion controls: drainage around the system won't compromise it.
  • Compliance with approved plans: actual installation matches the permit drawings.

Real estate transactions and disclosures

  • Many buyers and sellers opt for a pre-listing or closing-day inspection to verify system status.
  • Documentation you should have on hand includes the permit number, final inspection notice, and the as-built diagram.
  • If the home has been altered or expanded, ensure any changes were properly permitted and inspected.

Maintenance, records, and ongoing oversight

  • Keep all records: permits, inspection reports, as-built drawings, and maintenance receipts.
  • Schedule routine pumping and system checks per local guidance (typical residential intervals range broadly based on tank size, household water use, and soil conditions).
  • If you notice signs of trouble (gurgling sounds, slow drains, sewage odors, wet spots, or depressions in the drain field), contact your septic pro and local health department promptly.

Helpful official resources

  • DHEC On-Site Wastewater Program:
  • DHEC main site:

Septic Maintenance for Homes in Windsor

Windsor context and soil considerations

  • Windsor's humid subtropical climate brings heavy spring and summer rainfall, which can saturate soils and stress drain fields. Plan for wetter seasons and their impact on duration of system performance.
  • Soils in many Windsor neighborhoods are clay-rich, leading to slower infiltration and a higher risk of surface indicators after rain. If your yard stays damp or puddles persist, your drain field may be experiencing reduced absorption.
  • Water table fluctuations in spring and after storms can temporarily overwhelm the drain field. Allow recovery time after especially wet periods and avoid adding extra load to the system during those times.
  • Trees and shrubs near the septic system can send roots toward pipes and the drain field. Maintain a safe distance between vegetation and the system to minimize intrusion.
  • Setback rules and permit requirements are governed by SC DHEC and local authorities. Always verify distances from wells, property lines, and the drain field with official guidelines before any work is done.

Windsor maintenance plan (step-by-step)

  1. Schedule regular pumping based on tank size and household usage.
  2. Most homes with a 1,000–1,500 gallon tank should plan pumping every 3–5 years. Smaller tanks or higher wastewater flow may require sooner service. A licensed septic pumper can tailor timing to your home.
  3. Inspect the tank and components at least annually.
  4. Check baffles, lids, and the effluent filter (if present). Have the pumper remove built-up scum and sediment as part of the service.
  5. Shield the drain field from traffic and heavy work.
  6. Do not drive or park on the drain field; avoid heavy equipment or construction over the area to prevent soil compaction and damage.
  7. Manage water use and landscape runoff.
  8. Install and run low-flow fixtures; stagger laundry loads and fix leaks promptly.
  9. Direct roof and driveway runoff away from the drain field; consider rain barrels to reduce irrigation demand on the system.
  10. Monitor wastewater performance after wet seasons.
  11. If you notice slow drains, gurgling, odors, or wet areas over the drain field after heavy rains, schedule an inspection promptly to catch problems early.

Windsor-specific tips to protect your system

  • Planting choices matter: favor shallow-rooted grasses or ground covers near the system; avoid large trees or deep-rooting shrubs overhead.
  • Improve exterior drainage: ensure downspouts discharge at least 5–10 feet away from the septic tank and drain field; redirect runoff as needed.
  • Water management in droughts: avoid irrigating the drain field, and use water-saving practices to reduce load on the system.

Common Windsor issues and how to prevent them

  • Saturated soils after heavy spring rains: reduce irrigation, allow time for absorption, and schedule inspections if field indicators appear.
  • Root intrusion from nearby trees: maintain distance, prune problematic roots, and consider relocating plants that threaten the field.
  • Surface wet spots or odors after storms: avoid compaction, and have the system evaluated to confirm proper operation.

When to call a professional

  • Signs: gurgling toilets, slow drainage, sewage odors in the yard, damp spots over the drain field, or unusually lush growth on the field area.
  • Timing: routine pumping, diagnostics, or repairs should be performed by a licensed septic professional in Windsor/SC.

Official resources

  • SC Department of Health and Environmental Control (DHEC) Onsite Wastewater Program:
  • U.S. Environmental Protection Agency septic systems guidance:

Cost Expectations for Septic Services in Windsor

Septic Tank Pumping and Cleaning

  • What this includes:
    • Pumping out sludge and scum from the tank
    • Basic inspection of baffles and tank integrity
    • lid access and odor check; disposal of effluent per local rules
  • Windsor specifics:
    • Windsor's clay soils and variable tank access can affect pumping logistics and frequency; homes with aging tanks in tight lots may require scheduling around access constraints
  • Typical cost in Windsor: $250–$500 (often around $350)

Septic System Inspection and Certification

  • What this includes:
    • Visual inspection of tanks, lids, baffles, and pump chamber if present
    • Check for standing water, odors, effluent color, and overall system function
    • Written report with recommendations; pumping added if needed
  • Windsor specifics:
    • Real estate transfers in Windsor commonly trigger a formal inspection and may require proof of system operation; costs can rise slightly if pumping is recommended or required
  • Typical cost in Windsor: $150–$350

Drainfield Evaluation and Repair

  • What this includes:
    • Soil evaluation, dye testing, and infiltration assessment
    • Identification of failing components and repair options (or field replacement planning)
    • Coordination with permitting and scheduling for repairs
  • Windsor specifics:
    • Heavy clay soils and seasonal water table common in Windsor can lead to quicker drainfield distress; repairs may need relocation or upgraded soils
  • Typical cost in Windsor:
    • Evaluation: $2,000–$4,000
    • Targeted drainfield repair: $2,000–$8,000
    • Full drainfield replacement: $10,000–$25,000 depending on size and soil conditions

Septic System Installation / Replacement

  • What this includes:
    • Site evaluation, soil tests, design, and permitting
    • Tank setup, distribution system, and drainfield or mound installation
    • Start-up testing and system commissioning
  • Windsor specifics:
    • Lot size and soil variations in Windsor (including some properties needing mound or deeper placement) can shift the system type and permit costs
  • Typical cost in Windsor:
    • Conventional system: $7,000–$20,000
    • High-performance or mound/Aerobic systems: $15,000–$30,000

Aerobic System Maintenance and Service

  • What this includes:
    • Regular pump-outs, filter cleaning, control panel checks, and aerator/spray head servicing
    • Alarm/timer testing and maintenance contracts if applicable
  • Windsor specifics:
    • Aerobic systems are common in newer Windsor homes; ongoing maintenance frequency and part availability can influence annual costs
  • Typical cost in Windsor:
    • Per service: $200–$600
    • Annual service contracts: $300–$750

Tank Lids, Risers, and Access Improvements

  • What this includes:
    • Installing or upgrading risers and secure lids for easier future maintenance
    • Accessibility improvements to meet safety and inspection needs
  • Windsor specifics:
    • Many older Windsor tanks sit deeper; adding risers is a frequent upgrade to simplify access and pumping
  • Typical cost in Windsor: $800–$2,000

Lateral Line Repair and Drainage

  • What this includes:
    • Repair or replacement of buried lines from tank to drain field
    • Trenching, pipe replacement, backfill, and system testing
  • Windsor specifics:
    • Clay-rich Windsor soils can make excavation and pipe work more challenging, potentially extending project time
  • Typical cost in Windsor: $1,500–$6,000 (depends on length, access, and soil)

System Add-ons and Upgrades

  • What this includes:
    • Upgrades like effluent filters, upgraded control panels, or monitoring devices
    • Optional maintenance plans or remote alerts for early issue detection
  • Windsor specifics:
    • Upgrades can extend system life in Windsor's soil/climate; consider long-term maintenance budgeting
  • Typical cost in Windsor: $500–$3,000

Official resources

  • EPA: Septic Systems (