Public interest investigation
Explosive Testing, Public Access and Environmental Exposure at Holmans Test Mine
This investigation examines repeated underground explosive testing at Holmans Test Mine, subsequent recreational use of the mine, surrounding public access, environmental pathways, and whether appropriate monitoring, controls and information have been provided.
Human health • Air • Water • Land • Public access • Wildlife • Safety
Read the full technical investigation
The full technical report examines cumulative explosive activity, underground air and ventilation, potential energetic residues, hydrogeology, mine chemistry, public recreational access, public rights of way, neighbouring land, ecology and regulatory oversight.
Scope
This is not an investigation into whether Airsoft as a sport is safe
The issue is the environment in which it is taking place.
Holmans Test Mine is publicly described by its explosives operator as an underground testing facility with fully confined test chambers, forced-air ventilation, HSE-licensed explosive storage, and explosive test and trial facilities. At the same location, a commercial Airsoft operator advertises gameplay both inside and outside the mine.
This page does not state that explosions occur while recreational users are underground. No evidence held by this project establishes that. The question examined here is sequential rather than simultaneous:
Repeated testing → later public occupation of the same underground environment
The legitimate questions this raises
- What has been tested underground
- What remains after testing
- What is ventilated out, and to where
- What enters dust, surfaces or water
- What monitoring takes place
- How recreational areas are cleared before entry
- What participants are told
- How surrounding members of the public are protected
No harm is asserted here
This project has not established that any person, animal or watercourse has been harmed by activity at this site. It sets out what is publicly documented, what is reported, and what must be measured.
Both uses are publicly advertised
The explosives operator and the Airsoft operator each publish descriptions of their activities at this location. Those publications are the primary sources used below.
Primary operator material
What the operators themselves publish
Both descriptions below are drawn from the operators' own public websites. They are reproduced for factual context and are not presented as allegations.
Event Horizon / Precision Energetics — facility description
The operator publicly describes Holmans Test Mine as a unique underground testing facility and lists, among its features:
- More than one mile of underground tunnels
- Fully confined test chambers
- Forced-air ventilation
- HSE-licensed explosive storage
Wider company facilities are advertised for complex explosive testing, munition disposal, explosive storage, explosive formulation, and explosive manufacture/prototyping at the relevant facilities.
View operator's facility descriptionBlackout Airsoft Cornwall — site rules
The Airsoft operator publicly identifies its location as Holmans Test Mine, Troon, Camborne, Cornwall. Its published rules state, among other things:
- Helmets and torches must be used in the mine
- Under-16s must be accompanied by an adult
- Under-18s require full-face protection
- Gameplay occurs both inside and outside
Video evidence
Underground Airsoft — tunnels at Holmans Test Mine
Publicly published third-party footage is used here as observational material only. Nothing is treated as established unless the footage itself demonstrates it.
What the video shows
A structured, timestamped review of this footage is in progress. Each observation will be published in the table below only once it has been checked frame by frame, so that nothing is attributed to the footage that it does not actually establish.
Observation categories being logged:
- Areas entered underground
- Tunnel construction and lining
- Ventilation infrastructure visible
- Doors or blast-related infrastructure
- Enclosed chambers
- Standing or flooded water if visible
- Dust and surface conditions
- Protective equipment worn
- Participant comments about the mine
- Comments about testing or live/active use
- Sections accessed during gameplay
Each published entry will record: timestamp • what is visible or heard • why it matters • evidence status. Presenter statements will be separated from what the footage visibly establishes, and from what requires independent verification.
Video evidence gallery
Further publicly available footage is being collated, including material returned for searches such as “Holmans Mine Airsoft”, “Holmans Test Mine Airsoft” and “Troon Mine Airsoft” — among them a video titled “INSANE Airsoft Game In LIVE Test MINE Facility!”. Where a presenter calls the site a live test mine, this project will quote exactly what was said rather than paraphrase it into a stronger claim.
| Title | Channel | Date | Duration | Relevant timestamps | Claims made | Areas visible |
|---|---|---|---|---|---|---|
| Underground Airsoft – tunnels at Holmans Test Mine | To be confirmed | To be confirmed | To be confirmed | Review in progress | Review in progress | Review in progress |
| “INSANE Airsoft Game In LIVE Test MINE Facility!” | To be confirmed | To be confirmed | To be confirmed | Awaiting verified URL | Awaiting verified URL | Awaiting verified URL |
Entries are published only with a verified URL and a checked timestamp log. If you know of relevant public footage, tell us here.
Human health
What are people breathing after years of explosive testing?
This section describes what explosive testing can generate in principle. It does not state what was generated at this site.
What the products depend upon
- Energetic composition
- Charge size
- Confinement
- Oxygen availability
- Detonation efficiency
- Materials being destroyed
- Surrounding geological material
Potential products
- Gases
- Fine and ultrafine particulate
- Metal-containing particulate
- Pulverised mine rock
- Unreacted energetic compounds
- Energetic degradation products
- Combustion and detonation products
Toxicology
Some energetic compounds have recognised carcinogenic potential
Particular energetic compounds used in military and explosives applications have toxicological profiles that include carcinogenic potential or other significant health effects. The blanket statement 'explosives are carcinogenic' is too broad and is not made here.
RDX
A synthetic energetic compound used primarily as a military explosive. The US EPA's current IRIS assessment concludes there is “suggestive evidence of carcinogenic potential”. Animal evidence includes liver and lung tumours. EPA also identifies the nervous system as a human health hazard from sufficient RDX exposure. Potential exposure routes include ingestion and, depending upon circumstances, inhalation or dermal contact.
TNT
Documented toxic effects involve the blood, liver, skin and eyes. Occupational exposure has been associated with anaemia, abnormal liver function and cataracts. Historical EPA toxicological classification has treated TNT as a possible human carcinogen, based substantially upon animal evidence.
Source: ATSDR Toxicological Profile for TNT.
HMX
Available evidence has historically been insufficient to classify HMX as carcinogenic to humans. This distinction matters, and is stated here precisely because the project will not treat all energetic compounds as equivalent.
Public information
What are visitors told?
Before recreational visitors enter the underground workings, are they informed that the wider site is used for explosive testing? Specifically, are they informed:
- What testing occurs
- When it last occurred
- What substances were used
- What clearance procedures were completed
- Whether air was tested
- Whether surfaces were tested
- Whether mine water was tested
- Whether residual energetic material was considered
- Whether contaminated dust was considered
- What the ventilation period was
- Whether respiratory protection is necessary
This project does not state that visitors were not told. No evidence held establishes that either way. These are open questions to which records can supply an answer.
Did you play Airsoft at Holmans?
Were you given any written environmental, chemical or explosive-test safety information before entering the mine?
Risk control
PPE versus environmental exposure
These are different risk-control systems. Showing that players wore helmets and goggles does not, by itself, answer questions concerning air quality, chemical exposure or residual contamination.
Airsoft PPE
- Eye protection
- Face protection
- Helmet
- Suitable clothing
versus
Environmental / occupational controls
- Atmospheric testing
- Ventilation verification
- Contaminant monitoring
- Respiratory assessment
- Dust assessment
- COSHH where applicable
- Chemical hazard information
- Clearance procedures
- Environmental sampling
Cumulative exposure
One test is not the same as years of repeated testing
Resident evidence describes repeated testing over approximately ten years. Some individual weeks are reported to have involved as many as seven audible explosions.
Working scenarios
- 1 event/week × 52 × 10 = 520 events
- 2 events/week × 52 × 10 = 1,040 events
- 7 events/week × 52 = 364 events per year
- 7 × 520 weeks = 3,640 events over ten years
Cumulative testing calculator
Estimated number of events
1,040
Scenario — not verified firing history
This is arithmetic, not a record. It exists to show why the actual firing logs, explosive types and charge masses must be disclosed.
Sequence
Why weekday testing and weekend entry matters
Monday–Friday
Potential explosive testing.
Detonation
Gases, particulate, dust, rock disturbance, possible energetic residues.
Ventilation / settling / water contact
Products are removed, deposited on surfaces, or contact mine water.
Weekend
Recreational users enter the underground workings.
What is the clearance standard between these two activities?
This project does not assume that such measures are absent. It asks for the records proving what controls do exist.
Evidence sought
- Minimum re-entry time
- Air sampling
- Gas monitoring
- Dust monitoring
- Explosive residue monitoring
- Ventilation duration
- Chamber isolation
- Physical segregation
- Sign-off procedure
- Written handover
- Contaminated-area exclusion
Occupational hygiene
Why are masks relevant?
A mask is not automatically required merely because explosives have previously been used. The correct question is whether a risk assessment identified an inhalation hazard. If a contaminant exists at sufficient concentration, appropriate respiratory protection may form one part of a control regime.
However, occupational-hygiene practice prioritises elimination, containment, engineering controls, ventilation and monitoring before relying simply upon personal protective equipment.
The weak question is: “They weren't wearing masks therefore they were unsafe.”
The strong question is: what atmospheric evidence established that respiratory protection was unnecessary?
What the investigation should determine
- What contaminants were expected
- Whether measurements were taken
- What concentrations were measured
- What clearance limits applied
- Whether respirators were considered
- Whether respirators were required
Outside the mine
This does not end at the mine entrance
Gameplay is advertised outside as well as inside. The surrounding land includes homes, gardens, roads, woodland and — subject to verification — public access routes.
Features to be mapped
- Airsoft gameplay areas
- Mine entrance
- Surrounding land
- Public rights of way
- Neighbouring homes
- Gardens
- Roads
- Footpaths
- Woodland
Right of way status: verification pending
Residents report that the surrounding land contains a public right of way. This project will not publish the status or line of any route until it has been checked against the Cornwall Council Definitive Map and Statement. Once verified, the route will be shown on the interactive map with its definitive-map reference.
Containment
How are projectiles kept within the game area?
This is a separate question from underground chemical exposure, and is treated separately.
Controls to be investigated
- Boundary netting
- Fencing
- Backstops
- Physical barriers
- Vegetation used as a boundary
- Exclusion distances
- Firing directions
- Marshals
- Signage
- Public footpaths
- Neighbouring gardens
This project does not state that there is no netting anywhere. Where photographic evidence supports it, individual locations will be marked no physical projectile netting visible at this location — a statement about one photographed point, not about the whole boundary.
Question put to the operator
“What engineering or administrative controls prevent Airsoft projectiles from leaving the activity area or entering public access routes?”
Right of responseResident evidence
“Neighbours report finding suspected Airsoft BBs/projectiles within their gardens.”
Evidence status: resident report. Physical examples should be photographed, retained and independently identified where possible. These are described as suspected Airsoft BBs/projectiles — not “bullets” — until identified.
How to record a recovered projectile
Photograph the object beside a ruler, a date card and a location identifier. Where possible preserve samples in labelled evidence bags.
- Date found
- Location
- Approximate distance from site
- Colour and material
- Photograph
- Whether retained
Reported near-miss / person contact
Where a member of the public reports being struck, brushed or narrowly missed by an Airsoft projectile, an anonymised incident entry is created. Terminology is kept exact and unexaggerated, and each entry is labelled witness account — verification sought.
- Date
- Location
- Public or private land
- What was experienced
- Injury if any
- Witness
- Photograph
- Whether reported
- Response received
Public pathway safety
Where the two uses meet
Questions
- Is the public route physically segregated?
- Is there projectile netting?
- Are firing lines directed away from it?
- Are marshals positioned at crossing points?
- Is gameplay halted when walkers approach?
- Is warning signage present?
- Are members of the public required or expected to wear eye protection?
- What happens if someone enters unexpectedly?
Ecology
Wildlife, projectiles and residue
Two separate questions are kept separate: physical impact, and environmental residue.
Physical impact
Could wildlife crossing gameplay areas be struck by projectiles? Species of interest in this landscape include deer, badgers, birds, domestic animals and grazing animals where relevant.
See the wildlife registerEnvironmental residue
What happens to large numbers of BBs left in woodland and soil? The materials actually used must be determined before any pollution claim is made — conventional plastic, biodegradable polymer, or mixed composition.
“Biodegradable” is not synonymous with instant or harmless disappearance. Persistence will only be described using scientific evidence once the product and material are identified.
Conceptual model
Air, water and public access are connected
This is the centrepiece of the page: a source–pathway–receptor model expressed as a single chain. Every stage is a hypothesis to be tested by measurement, not a finding.
Testing
Airborne pathway
Water pathway
Human pathway
Ecological pathway
Hazard is not the same as exposure
A substance may have carcinogenic or toxic properties. That alone does not prove that it was used at Holmans, that residue remained, that people encountered it, that the concentration was harmful, or that illness resulted.
- Source
- What substances were used?
- Pathway
- Could they reach people or the environment?
- Concentration
- At what level?
- Duration
- For how long?
- Receptor
- Who or what was exposed?
- Health outcome
- Is there evidence consistent with exposure?
But the hazard must not be minimised either
The absence of existing public monitoring data is not evidence that exposure did not occur.
Where potentially hazardous energetic compounds have been repeatedly used in a confined underground environment, the scientifically appropriate response is to identify the substances, reconstruct operations and obtain environmental measurements.
That is particularly important where the same underground complex subsequently admits recreational visitors.
Disclosure
Data that should now be obtained
Each item below is a record that either exists or does not. Producing them would answer most of this page.
Explosive testing
- Every test date
- Number of shots
- Explosive type
- Explosive mass
- Safety Data Sheets
- Test chamber
- Test article
- Incomplete detonations
- Misfires
- Explosive disposal
Air
- Post-blast gas readings
- Particulate measurements
- Respirable dust
- Ventilation records
- Clearance criteria
- Clearance time
- Air-quality certificates
Underground surfaces
- Dust sampling
- Wipe testing
- Energetic residue
- Heavy metals
- Mine mineral dust
Water
- Flooded chambers
- Mine drainage
- Groundwater
- Streams
- Sediments
- Sulphate
- Metals
- Energetic compounds dictated by inventory
Public access
- Airsoft dates
- Participant numbers
- Age groups
- Underground areas used
- Safety briefings
- Signed waivers
- Environmental hazard information
- Post-test handover
Outside
- Rights-of-way map
- Projectile containment
- Boundary inspection
- Complaints
- Recovered BBs
- Incidents involving walkers or neighbours
- Wildlife incidents
Public interest
Members of the public should not have to guess what environment they are entering
Holmans Test Mine is publicly described as an underground explosive-testing facility and is also publicly advertised as an Airsoft venue. The legitimate public-interest question is therefore not whether Airsoft is inherently unsafe. It is whether repeated explosive testing, underground environmental conditions, public recreational access and surrounding public access have been assessed together.
The answer should be capable of demonstration through firing records, explosive inventories, air monitoring, ventilation records, environmental sampling, risk assessments, public-access controls and incident records.
If those safeguards exist, publishing them can provide reassurance. If they do not exist, that is itself a matter requiring regulatory examination.
Evidence request
Have you used Holmans Test Mine?
We would like to hear from Airsoft participants and former participants, marshals, workers, contractors, local walkers, neighbouring residents, former employees and environmental specialists.
Especially useful
- Safety briefings
- Waivers
- Photographs
- Video
- Testing dates
- Explosions heard
- Projectiles found outside the activity area
- Air or water concerns
- Injuries or symptoms
- Maps showing where incidents happened
Contributors' identities are protected unless they explicitly consent to publication. Names, health information and exact addresses are never published.
Evidence standard
Every factual statement on this page carries a label
No statement is ever silently moved from one category into another. The credibility of the project depends on that separation.
Sources cited on this page
- Precision Energetics — facilities description
- Blackout Airsoft Cornwall — site rules
- US EPA IRIS — RDX Toxicological Review
- Underground Airsoft at Holmans Test Mine (YouTube)
- ATSDR Toxicological Profile for TNT (US Agency for Toxic Substances and Disease Registry).
- Cornwall Council Definitive Map and Statement (rights of way status — check pending).