NMX‑FOL‑30 / Rev 00 / fuel storage / tank · pipework · dispensing 2026 · Product Page

NMX-FOL-30 · ENGINEERED TO ORDER — UNDERGROUND FOL STORAGE INSTALLATIONS

Buried. And still provable.

Going underground buys real things — it removes the fire-spread exposure and visual signature of above-ground tankage and frees the surface. It also moves every failure mode out of sight, which turns the design question into a single one: how will anyone know? So the enemy is named honestly — the soil, not the fuel — and answered with coating, cathodic protection and a monitored interstitial space that makes leakage a reading rather than an inference. Anchorage is sized for the empty condition, because an empty tank in a high water table is the one that floats. Buried lines get containment, fall and test points that prove them without excavation. And where tanks are scattered across a station, the job stops being tankage and becomes supervision. We provide the tankage, pipework, dispensing, detection, testing and commissioning; civil works are executed with your own agencies. No delivered installation is claimed.

Enquire — underground FOL storage Capability sheet (PDF)

Illustrative image, not a delivered system — a large horizontal cylindrical steel storage tank hanging on lifting slings above an open excavation: plain dark green coated steel about six metres long with welded lifting lugs and flat strap seats, the pit below bedded with pale sand and a poured concrete ballast slab with steel hold-down straps laid ready, timber shoring to the pit walls, excavated spoil to one side, overcast light, no people and no markings

Fig · 01 Bedding, ballast slab and hold-down straps waiting — the anchorage is designed before the tank arrives, and for the empty case — illustrative, not a delivered system

The enemy

the soilcoating · cathodic

Anchored

for emptystraps · ballast slab

Detection

a readinginterstitial · sump

Scattered

one place to seegauging · alarms

Approved

PESO/CCOEthird-party inspection

ISO 9001 / 14001 Engineered to order Fuel-handling franchise Tightness-tested & documented Noida · India

Overview

How will anyone know?

An above-ground tank is inspected by walking round it. A buried one cannot be, and that single fact reorganises the whole design. Every decision below — double wall instead of single, cathodic protection with test posts instead of coating alone, test points on lines, interstitial monitoring, gauging and reconciliation — exists to replace an inspection nobody can perform with a reading somebody can take. The tank is the easy part; the evidence is the engineering.

Illustrative image, not a delivered system — looking down into an open square concrete access chamber over the crown of a buried steel tank: a heavy bolted circular manhole cover with three flanged pipe stubs rising from it, a slim monitoring probe entering a sealed gland fitting alongside, coated black pipework turning into the chamber wall, damp grey concrete with water staining, no people and no markings

Fig · 02 The access chamber — the only part of the installation anyone will see again, so everything that needs reading is brought here — illustrative, not a delivered system

The soil is the enemy, not the fuel. Product inside a tank is chemically undramatic; the aggressive environment is outside, and it is permanent. So the specification runs coating plus cathodic protection with test posts that can actually be read, because protection nobody measures is a hope rather than a system. Beyond that, double-wall construction with a monitored interstitial space is what changes the character of the installation: instead of inferring integrity from inventory drift over weeks, the space between the walls is monitored continuously and a breach of the inner wall is caught while the outer one is still holding everything in.

The empty tank is the one that floats. It is the failure that surprises people, because intuition says a full tank is the demanding case. A buried tank is a large sealed volume: nearly full it is heavier than the water it displaces, and nearly empty it is not. Put a high water table or a flooded excavation around it and it lifts — shearing pipework, cracking the chamber and writing off the installation. So hold-down straps and the ballast slab are sized for the empty condition, and the tank is not left unfilled in an open, wet excavation during construction.

“Scattered” changes the problem. A single tank farm is a tankage job. Tanks distributed across a station are a supervision job: each location needs its own containment, detection and gauging, and unless those readings arrive somewhere central, the station ends up with many installations and no picture of any of them. That is why the monitoring architecture — not the tank size — is usually the part of a scattered requirement worth arguing about.

We provide the tankage, pipework, dispensing, detection, controls, testing and commissioning. Excavation, chambers and hardstanding are executed with your own civil agencies — this page does not claim an EPC scope it does not perform.

Provable

A reading, not an assumption

Interstitial and sump monitoring, cathodic test posts, gauging and reconciliation — every buried failure mode gets an instrument.

Anchored

Sized for empty

Straps and ballast designed against flotation in a high water table, which is the condition that actually destroys installations.

Supervised

Scattered, but seen

Distributed tanks brought back to one place to see them all — otherwise a station has many unknowns rather than one system.

Architecture

Bed it, set it, pipe it, prove it.

The schematic follows the installation — bedding and anchorage first, the protected tank set, pipework, venting and dispensing built around it, then the proving that starts at commissioning and never stops — and shows what each stage consists of: tank and corrosion protection, buried pipework and test points, dispensing and water separation, and detection, gauging and the record.

FIG · 03FOL ARCHITECTURE · TANK + PROTECTION / BURIED PIPEWORK / DISPENSING · DETECTION, GAUGING & RECORD

Fig · 03 Known, not assumed — a reading for every buried thing

Arc · 01

Tank & Corrosion Protection

Coating plus cathodic protection with readable test posts, and double-wall construction with a monitored interstitial space.

Arc · 02

Buried Pipework

Fill, suction, vent and recovery lines with secondary containment, correct fall, and test points that prove a line without excavation.

Arc · 03

Dispensing

Pump, meter, filter and water separator on a contained plinth — because water is what a buried tank quietly collects.

Arc · 04

Detection, Gauging & Record

Interstitial and sump monitoring, automatic gauging, alarms and inventory reconciliation — brought to one place for scattered sites.

Installing, replacing or instrumenting underground fuel storage? Send the capacities, the number of locations and the site conditions — a clause-by-clause compliance matrix within two working days · [email protected]

Send tender spec

Specifications

Reference installation, built to the site.

The parameters below describe a reference installation. The capacity, tank construction, anchorage, pipework routing, dispensing arrangement and monitoring architecture all follow from three givens: the product and throughput, the ground and water table, and how many locations the station needs.

Illustrative image, not a delivered system — a fuel dispensing point on a concrete hardstanding: a plain grey steel dispenser cabinet on a raised plinth with a low kerbed containment surround, a thick black hose coiled into its holster, two protective bollards in front, a slotted drainage channel across the hardstanding, low boundary wall behind, overcast daylight, no people and no branding

Fig · 04 The dispensing point — contained, bollarded and drained, with filtration and water separation ahead of the nozzle — illustrative, not a delivered system

Where underground fuel installations go wrong

Anchorage sized for the full tank, so the first flooded excavation or high water table lifts an empty one. Corrosion protection specified and then never read — cathodic protection without periodic test-post readings is an assumption wearing a certificate. Single-wall tanks with no interstitial space, leaving leak detection to inventory drift, which finds a leak only after it has been running for weeks. Test points omitted, so proving a buried line later means digging it up and nobody does. Vent and fill positions chosen for the installer's convenience rather than for where vapour goes. No water management, so the tank accumulates water for years until it reaches the dispensing point. Scattered sites with no central monitoring. And records that stop at handover, when the statutory and inventory record is precisely what makes the installation defensible for the next twenty years.

So the discipline runs the other way. Anchorage is calculated for the empty condition and the tank is not left unfilled in a wet pit. Cathodic protection comes with test posts and a reading schedule. Double-wall and interstitial monitoring make integrity continuous rather than inferred. Lines carry permanent test points. Venting is positioned by where vapour must go. Filtration and water separation sit ahead of the nozzle, with a means of drawing water off the tank bottom. Scattered locations report to one console. And the installation is handed over with tightness-test records, PESO/CCOE documentation and a reconciliation method the station can run itself.

Full specification — expand

System	Underground FOL storage installation — buried tankage, pipework, venting, dispensing, leak detection, gauging, tightness testing & commissioning
Governing Idea	Everything you bury must be provable from outside — each buried failure mode is given an instrument rather than an assumption
Tank	Coated steel, single or double wall; double-wall with a monitored interstitial space where integrity must be continuous rather than inferred; manhole & sump access
Corrosion Protection	External coating + cathodic protection with readable test posts and a reading schedule — the soil is the aggressive environment, not the product
Anchorage	Hold-down straps & ballast slab sized for the EMPTY condition — flotation in a high water table is the failure that destroys installations
Buried Pipework	Fill, suction/pressure, vent & recovery lines — secondary containment, correct fall for drainage, permanent test points to prove a line without excavation
Venting	Vent stacks at height, pressure & vacuum relief, flame arrestors — positioned so displaced vapour goes where it is safe
Dispensing	Pump, meter, filter & water separator on a contained, kerbed plinth with bollard protection & drainage; hose & nozzle management
Water Management	Water is the contaminant a buried tank collects by condensation & ingress — separation ahead of the nozzle and a means of drawing water off the tank bottom
Leak Detection	Interstitial & sump monitoring, automatic tank gauging with alarms, and inventory reconciliation — in against out against gauge
Scattered Installations	Distributed locations each with containment, detection & gauging, reporting to one console — a supervision problem, not a tankage one
Testing	Tightness testing of tank & lines at commissioning and periodically; calibration of gauging; documented results
Hazardous Area	Flameproof & intrinsically safe equipment in the zoned areas; earthing & bonding against static during filling
Statutory	Designed & documented for PESO/CCOE approval, with third-party inspection & the test records the authority expects
Scope Boundary	Ours: tankage, pipework, dispensing, detection, controls, testing, commissioning & documentation. Customer's civil agencies: excavation, chambers & hardstanding
The Family	The storage end of the delivered fuel-handling franchise on this site — beside the refueller & bowser, the pressure & cryogenic tankage and the pipeline-distribution work
Status	Engineered to order · quoted across underground FOL tank, field storage-tank & scattered-installation requirements · no delivered installation is claimed on this page

PDF · 1 page

Underground FOL Storage Installations — Capability Sheet

Tender Response

Send capacities, locations & site conditions — compliance matrix in two working days

Variants

One idea, four scopes.

Requirements arrive as a single underground tank, a scattered set across a station, a dispensing point, or the instrumentation of tanks that are already in the ground.

Var · 01

Underground Tank Installations

Single tanks from small field capacities upward — protected tankage, anchorage, pipework, venting and commissioning with tightness records.

Var · 02

Scattered Multi-Site Installations

Tanks distributed across a station with per-location containment and detection, reporting to a single monitoring console.

Var · 03

Dispensing Points & Fuel Handling

Pump, meter, filtration and water separation on contained plinths — the issuing end, integrated with the station's records.

Var · 04

Retrofit Detection, Testing & AMC

Instrumenting tanks already in the ground — gauging, sump and interstitial monitoring where possible, tightness testing, and AMC.

Applications

Wherever fuel is held on site.

Stations, depots and installations that store and issue their own product.

A · 01Defence stations & field installations

A · 02Transport & vehicle depots

A · 03Standby generation & plant fuel storage

A · 04Airfield & ground-support fuel points

A · 05Industrial sites & process plants

A · 06Remote & scattered station networks

FAQ

Common questions.

Plain-language answers from the engineering team.

Q · 01 Why bury the tank at all, given it makes everything harder to inspect?

Because the things it buys are worth the difficulty, provided the difficulty is engineered for rather than ignored. Burying removes a large volume of product from the surface, which reduces fire-spread exposure and the consequences of impact or mishandling; it removes a conspicuous structure from a site where that matters; it frees the surface for traffic, parking or building; and it keeps the product cooler and more thermally stable, which reduces vapour losses and the daily breathing that an above-ground tank suffers in strong sun. Against that sits one real cost: you can no longer walk round the tank and look at it, and visual inspection is how most tankage is actually managed. The mistake is to bury a tank designed as though it were still visible. The correct response is to accept that inspection has been replaced by instrumentation, and to specify accordingly — double wall with interstitial monitoring, cathodic protection with readable test posts, permanent line test points, automatic gauging and a reconciliation routine. Done that way, a buried installation is arguably better understood than an above-ground one, because it is measured continuously rather than looked at occasionally.

Q · 02 Why is anchorage sized for an empty tank rather than a full one?

Because a buried tank is a large sealed volume, and the load case that threatens it is buoyancy, not weight. Full, it is heavier than the water it displaces and sits happily. Empty or nearly empty, it is a very large float with a thin steel skin, and if the surrounding ground becomes saturated — a high water table, a wet season, or simply an excavation that fills with water during construction — the uplift can exceed the weight of the tank and its cover. What follows is not subtle: the tank lifts, shears its pipework, cracks the chamber and lifts the hardstanding above it, and the installation is effectively written off. So the calculation is done for the worst realistic case: tank empty, ground saturated to the highest credible level. The answers are a concrete ballast slab and hold-down straps sized to that uplift, correct backfill, and where the ground demands it, drainage to limit the head. There is also a construction-phase rule that matters just as much: an empty tank is never left sitting in an open, wet excavation — it is anchored, backfilled and, where practical, ballasted with water as soon as it is set.

Q · 03 How is a leak actually detected in something you cannot see?

In layers, and the difference between a good installation and a poor one is how many of them exist. The strongest is interstitial monitoring: with a double-wall tank, the space between the walls is monitored continuously, so a breach of the inner wall raises an alarm while the outer wall is still containing everything. That converts a leak from an environmental event into a maintenance job. Next is sump and chamber monitoring — sensors in the tank-top chamber and in line sumps, which catch fitting and joint leaks, statistically the most common source. Then automatic tank gauging, which measures product level and water level continuously and can run a static leak test during quiet hours by watching whether the level moves when nothing should be moving. Then inventory reconciliation: what was delivered in, against what was dispensed out, against what the gauge says remains — over enough days, a persistent discrepancy is a leak, and this is the layer that catches slow losses no instantaneous test would notice. And finally periodic tightness testing of tank and lines, which is the formal proof. On lines specifically, permanent test points are what make later testing possible without excavation — omit them and the pipework becomes effectively untestable.

Q · 04 What changes when the tanks are “scattered” across a station?

The nature of the project. A single tank farm is a tankage and pipework job with one set of everything. A scattered installation — several tanks at the points of use across a large site — is a supervision job that happens to involve tanks, and it is usually specified as though it were the first thing. Three consequences follow. First, everything multiplies: each location needs its own containment, venting, chamber, detection, gauging and dispensing, and each is a potential unattended failure point. Second, attention divides: nobody visits eight scattered locations as often as they visit one farm, so the very sites most in need of monitoring get the least human contact. Third, and decisively, the readings are useless where they are generated — an alarm panel on a chamber lid at a remote corner of a station is an alarm nobody hears. So the architecture that matters is the one that brings every location's gauge, water level, sump and interstitial status back to one console, with alarms that reach a person. Designed that way, scattering becomes an advantage: product is stored where it is used, with less handling. Designed without it, a station acquires several independent unknowns.

Q · 05 Why does water get so much attention?

Because it is the contaminant a buried tank is guaranteed to accumulate, and the one that does the downstream damage. It arrives two ways. Condensation: the tank breathes as product is drawn off and as temperature changes, humid air enters through the vent, and moisture condenses on cool surfaces and runs to the bottom — a slow but relentless process. And ingress: through a fill-point cover that ponds, a worn seal or a chamber that floods, which delivers water in quantity rather than by the drop. Once at the bottom of the tank it causes three problems: it promotes internal corrosion at the very lowest point of the shell; it supports microbial growth at the fuel-water interface, producing sludge that blocks filters and accelerates pitting; and if the suction ever reaches it, water goes out to the equipment, which is the expensive failure. The response is layered and unglamorous: keep it out with sealed covers and drained chambers; measure it with a gauge that reports water level separately from product level; remove it with a means of drawing off the tank bottom as routine maintenance; and catch what escapes with filtration and water separation ahead of the nozzle.

Q · 06 What exactly do you provide, and what stays with our own agencies?

Worth being explicit, because these requirements are often written as "supply and construction" and it matters that a supplier says which half it is actually good at. What Neometrix provides: the tankage — tank specification and supply, coating, cathodic protection and its test posts, double-wall and interstitial provision, manholes and sumps; the anchorage design — uplift calculation and the strap and ballast arrangement; the pipework — fill, suction, vent and recovery lines, containment, fall, and permanent test points; the venting — stacks, relief and flame arrestors; the dispensing — pump, meter, filtration and water separation, plinth containment; the detection, gauging and controls, including the console that brings scattered locations together; the tightness testing, commissioning, calibration and documentation for PESO/CCOE approval and third-party inspection; and training, spares and AMC. What is bought-in certified: pumps, meters, gauging and detection instruments, filtration elements and hazardous-area electrical equipment. What stays with your own civil agencies: excavation and shoring, the concrete chambers and slabs, backfill and hardstanding — we design to them and work alongside them. Engineered to order; quoted across underground FOL tank, field storage-tank and scattered-installation requirements; no delivered installation is claimed on this page.

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The pressure-storage sibling — the same statutory and containment discipline.

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Buried and building distribution — pipework proven before it is covered.

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Send the capacities
and the locations.

The projects desk replies within two working days with a clause-by-clause compliance matrix and a budgetary quotation. Write to [email protected] or use the form.

Enquire — underground FOL storage Capability sheet (PDF) +91 7777 876 876

ISO 9001 / 14001 ENGINEERED TO ORDER — UNDERGROUND FOL STORAGE INSTALLATIONS PROTECTED TANKAGE · ANCHORED FOR EMPTY · CONTAINED PIPEWORK · DETECTION & GAUGING ENGINEERED IN NOIDA · INDIA