Any activity or workplace that causes contaminants to be
released into the air in Texas requires authorization from the
TCEQ. De minimis is one of four choices a small business owner or
local government representative may have available to them to
satisfy air authorization requirements in Texas. The other three
are:
If a small business owner or local government representative
determines that an operation or activity meets the requirements of
the De Minimis Rule and can show suitable proof that de minimis
applies to their location, then no other state air authorization is
required.
Ways to be De Minimis
List of De Minimis Facilities
Paragraph 1 of the rule is the easiest way to determine if an
operation qualifies as de minimis by providing for an approved
list. That list may be obtained at:
The list may also be obtained by calling the TCEQ's Air Permits
Division in Austin at 512/239-1240 and asking for the latest list
of De Minimis Facilities.
De Minimis Rule
-
Material Use - Paragraph 2 of the rule shows de
minimis limits by the amount and type of materials that are allowed
to be used in a year's time. View the rule at
30 Texas Administrative Code, Chapter 116 
-
Effects Screening Levels (ESL) - Paragraph 3 of
the rule shows how a facility meets the De Minimis Rule by
evaluating the daily and annual emissions from the site. This chart
shows the sitewide emission rate caps based on ESL: 30 TAC Chapter
116.119(a)(3) (PDF), (Help with PDF)
Record Keeping: It's the Law
Although record keeping is important for any operation, it is
especially important for a small business or local government
claiming de minimis. The overall requirements for keeping
appropriate records and the authorization for TCEQ investigators to
examine those records are found in the Texas Health and Safety
Code, Subtitle C, Air Quality, Chapter 382:
Monitoring Requirements and Examination of Records (Section
382.016)
At a minimum, de minimis record keeping should consist of
invoices for amounts of materials purchased. Facility owners and
operators should maintain enough information to demonstrate they
meet the De Minimis Rule requirements. Remember that these records
must be produced upon request.
In Conclusion
The phrase "de minimis" literally means "of minimum impact." It
is intended that qualification for de minimis means there will be
no significant contamination of the air. And it is also important
to remember that the entire job site must meet de minimis standards
in order to qualify under this rule.
Don't forget that de minimis, if it qualifies, is just one of
four options when it comes to satisfying state air authorization
requirements in Texas. De minimis and Permit By Rule are attractive
to small business owners and local government facility operators
because there are no fees involved and the paperwork is minimal.
But the two other options, a Standard Permit or a New Source Review
Permit, may also be utilized, especially if it is felt that future
growth would generate air emissions above the amounts allowed by de
minimis or Permit By Rule.
Free, confidential help with questions on air, water, waste, or
pollution prevention issues is available from the Small Business
and Local Government Assistance Section at 1-800-447-2827 or
contact a Compliance
Assistance Specialist in your area.
