Composting facility odor monitoring that doubles as process data
The ammonia and methane coming off your piles tell you something before the neighbors do. NH3 means you're giving away nitrogen. CH4 means part of a pile went anaerobic while nobody was looking. SmartCompost reads both around the clock at the pile, on the pad, and at the property line, with wind speed and direction from your own weather station stamped on every reading. You end up with the odor record the state agency asks for and process data your operators can use the same shift.
Ammonia and methane are process data, not just nuisance
Most odor systems treat gas as a complaint risk and stop there. On a compost pad, those same numbers point back at mix, moisture, and airflow.
- Your C:N ran too low, or the pile got hot and alkaline enough to strip nitrogen out. Every pound that leaves as ammonia is a pound that never makes it into finished product. The fix is the recipe or the carbon source, not the biofilter.
- Something in the pile core has gone anaerobic. Usually free air space collapsed: too wet, packed down by the loader, blower short-cycling, a plugged aeration lateral. Methane on the pad means a batch is going bad right now.
- Anaerobic conditions plus sulfur in the feedstock. Food scraps, biosolids, and DAF skimmings all bring it in. This is the group that gets you phone calls, and it spikes the second somebody opens up a wet pocket.
- The organic fraction behind most of what people actually smell downwind. Spikes line up with turning, tearing into an old pile, or a hot load sitting on the tipping floor.
- The aerobic side of the ledger. CO2 up with methane flat is a pile eating and breathing. CO2 flat with methane climbing is a pile that quit on you.
- Grinding, screening, and loader traffic on a dry pad. Dust complaints and odor complaints come from the same neighbors, often in the same week. One node covers both.
The six spots your complaints come from
You already know your site. The reason to instrument it is knowing which of these was running hot at 4:15 a.m., when the call came in.
Tipping and receiving
Fresh food scraps sitting past quitting time. Standing leachate on the floor. A load that showed up already septic. Shortest path from a bad delivery to a bad night.
Active windrows and ASP
Turning lets out whatever the core built up. On aerated static piles, read the gas against the blower cycle. On windrows, watch what the turner exposes on each pass.
Curing pad
Quiet, and that's the problem. Piles get stacked deeper than anybody planned, rain drives the moisture up, and the middle goes anaerobic long after people stopped watching it.
Screening and overs
Dust and TVOC together. Trommel work on a dry, breezy afternoon pushes PM10 across the property line and sends coarse organics back into the mix.
Biofilter or scrubber outlet
You paid for that media. Readings before and after tell you when it's drying out, channeling, or worn out, instead of letting a neighbor tell you.
Leachate and stormwater ponds
Sulfides off a stagnant pond don't care what the piles are doing. Worth its own node when the pond sits between your pad and the nearest houses.
Pile, pad, and property line on one platform
Three instruments, one data set. Most organics recycling facilities run three to eight monitoring points, depending on layout and how close the neighbors sit.
Smart.Mini, pile by pile
Battery-powered and handheld. Walk the row. Take a reading before and after turning, put batch 14 up against batch 15, check the recipe change you made Monday. It rides with whoever runs the pad.
Smart.Compost, fixed on the pad
Full gas suite plus the four dust fractions, running around the clock at receiving, the active pad, curing, or the biofilter outlet. This is the node that catches the anaerobic batch overnight.
Smart.Odor, at the fence
Perimeter nodes aimed at your closest receptors. You get the dispersion picture and a timestamped answer to the only question anybody asks after a call: was it us?
Local weather station, every reading
Wind speed and direction logged on your site, not pulled from an airport across the county. Every gas and dust value carries the wind it happened in.
What changes on the pad
The data is worth whatever your crew does with it. Here's the loop.
Alert before the plume
Threshold crossings hit your phone and your email while the number is still climbing. That buys time to cap a pile, hold a load, or move a turning window.
Trace it to an area
Node position plus wind direction narrows it to a zone instead of the whole site. Then Smart.Mini walks the row and finds the batch.
Correct the process
Add carbon. Add bulking agent. Drop the pile height. Clear the aeration line. Pull the moisture down. The gas curve tells you within a day or two whether it worked.
Close the complaint properly
Every call gets matched against readings, wind, and time of day. Sometimes that clears you. Sometimes it doesn't, and you go fix the thing. Both beat guessing.
Keep the record
Continuous history exports for your odor management plan, your permit file, and the county inspector who shows up without calling first.
The paper trail your permit file is missing
Odor rules in most states are written in words, not numbers. Objectionable. Unreasonable interference with the enjoyment of property. That leaves you defending a judgment call with a handwritten odor log.
Continuous history, not spot checks
Readings run around the clock. Nights, weekends, and holidays are exactly when complaints come in and exactly when nobody's on site with a clipboard.
Wind on every record
A complaint from a receptor that sat upwind of your pad at that hour is a fact you can put in writing.
Timestamped and unedited
Data goes straight to the platform and stays there. Nobody retypes a field sheet from memory three days later.
Reports built for the agency
Period summaries by node, by gas, by wind sector. Formatted to attach to an odor management plan or a complaint response.
Before and after evidence
When you spend real money on a compost cap, a biofilter rebuild, or an aeration retrofit, the record shows what it bought you.
Sites we build this for
Municipal yard trimmings and food scraps
Windrow or ASP, food scrap volume climbing every year, and houses that showed up after the site did.
Commercial organics recycling
Third-party feedstock you don't control. Incoming load quality is the odor variable you see last and can do the least about.
Biosolids and co-composting
Sulfur-heavy feedstock and a permit that gets read closely. H2S and mercaptans lead the list here.
In-vessel and containerized systems
Process gas at the exhaust and at the biofilter, plus perimeter coverage on the receiving side. Receiving is usually the weak point.
Sites already in a permit fight
Complaints on file and a deadline in front of you. Continuous data is the fastest way to sort out what's yours from what isn't.
Sites planning an expansion
Baseline now, before you add tonnage. It's a much easier argument for more throughput with a year of readings behind you.
What we are and what we're not
Where we come from
SmartCompost has been building environmental monitoring hardware and software since 2019. That hardware runs at eight or more plants today and logs more than 350,000 readings a month. All of that work is in Brazil. We're opening in the United States now, and we'd rather say that up front than have you find it out later.
What we don't have
No EPA method approval. No MCERTS or air district certification. No US reference list yet. If your permit calls for an approved reference method to make a compliance determination, this is not that instrument, and you'll hear it from us on the call, not after the PO.
What it's good for
Continuous process and perimeter data, matched to wind, kept in a record you can audit. Thresholds get set against your own baseline and the way you actually run. Operators use it to run cleaner piles and to answer complaints with something better than memory.
Frequently asked questions
Can continuous sensors replace a periodic sampling program?
No, and anybody who tells you otherwise is selling. Continuous instruments give you 24/7 coverage, trend, and wind correlation. A sampling round gives you a defensible number for one moment in time. Two different jobs. What tends to happen is that sites keep the sampling their permit requires and quit paying for the extra rounds that only confirm what the continuous record already showed.
How many monitoring points does a composting site need?
Three to eight at most organics recycling facilities. Layout drives that number more than acreage does. A linear site with houses on one side needs fewer points than a site with receptors on two sides and a curing pad at the far end. We walk the site plan and the prevailing wind with you before we scope anything.
Why measure methane? We run an aerobic process.
Every aerobic pile has anaerobic pockets. The question is how many and how big. Methane on the pad is the fastest tell that free air space collapsed somewhere: wet feedstock, loader compaction, a pile stacked too tall, a plugged aeration lateral. You want that on day 4, not when the pile stinks on day 20.
Will this hold up if the county or the state agency comes at us?
You get a continuous, timestamped record with wind attached to every reading. That's a lot stronger than a log filled in by hand at the end of a shift. It is not a compliance determination and we don't sell it as one. What it changes is the conversation, from opinion against opinion to a timeline.
Does dust monitoring matter for a composting facility?
If you grind or screen, yes. PM10 off a trommel on a dry, windy afternoon crosses the property line the way odor does, and it brings its own complaints. Measuring gas and four dust fractions at one node puts both in a single record, so you can tell when the dust event and the odor event are one and the same.
Can the hardware survive a compost pad?
That's what it was built for. Outdoor pads, wash-down, ammonia-heavy air, and dust that gets into everything. Nodes are field serviceable and sensors swap out in place. Calibration and service intervals go into the plan on day one, because a sensor nobody maintains stops being data and starts being a liability.
What is the first step?
Send us a site plan and an honest account of your complaint history. We size the point count, place the nodes against your prevailing wind, and set thresholds around how you actually operate instead of generic numbers. There's no online configurator and no list price. Every site lays out differently, so we scope it on a call.
Read the piles and the fence line at once
Tell us how the site runs, windrows, aerated static piles or in-vessel, and which receptors are closest. We will propose a plan.
Talk to our team →