SWPPP Addendum & Re-Permit Services

When must a SWPPP be amended?

TXR150000 requires the permittee to revise or update the SWP3 within seven days of changing site conditions based on updated plans and specifications, new operators, new areas of responsibility, or changes in BMPs. In practice: if the answer to "is the plan still true?" is no, a short clock is already running on making it true again.

The inspection clock

Inspections are the other trigger, and they run on their own schedule. The SWP3 must be modified based on the results of inspections when necessary to better control pollutants in runoff, and revisions must be completed within seven calendar days following the inspection. That is why amendments ride best with the inspection stream — the finding and the fix belong to the same week, on paper as well as on the ground.

When the state must hear about it

Some changes stay in the binder; others go up the chain. If relevant information provided in the NOI changes, the operator must submit a Notice of Change to TCEQ at least 14 days before the change occurs — or, where advance notice is not possible, within 14 days of discovering the change. Terradyne prepares the TCEQ Notice of Change and revises the SWP3 narrative to match. The form and the narrative have to move together — a notice that contradicts its own plan is a new problem, not a correction.

Re-permitting when the cycle turns

Permit coverage is written against a permit that itself expires. The 2023 reissuance of TXR150000 required operators of ongoing large construction activities authorized under the 2018 permit to submit an NOI to renew authorization, or an NOT to terminate coverage, within 90 days of the new permit's effective date. The TPDES Construction General Permit TXR150000 is effective March 5, 2023 through March 5, 2028. A permit cycle ending is not a paperwork event you schedule for the deadline week. The binder, the forms, and the filings all have to land together. Terradyne prepares SWP3 addenda and handles TCEQ permit-cycle re-permitting. Sites that treat the cycle change as routine paperwork keep building; sites that miss it are suddenly discharging without authorization. The renewal is also the natural moment to fix everything the binder has been tolerating — stale contacts, outgrown maps, controls the site no longer uses. A re-permit filed against a cleaned-up plan starts the new cycle the way the old one should have ended.

How the desk works a change

Every change follows the same short path. First, scope: what actually changed on the ground, and which documents it touches — the narrative, the map, the filings, or all three. Second, the paper: the addendum drafted as a controlled revision, the map redrawn where geometry moved, the notice prepared when the change belongs on the state's file. Third, the record: what changed, when, and why, entered where the next auditor will look for it. The order matters because the documents certify each other — a corrected filing pointing at an uncorrected plan is a mismatch someone else will eventually find.

Speed is the service. Change clocks are measured in days, and they start when the site changes, not when someone remembers the binder. The desk turns amendments on the cadence the deadlines demand, which is why it pairs naturally with the inspection stream where changes surface first.

What arrives when the desk is done

Every engagement ends the same way: a narrative that matches the site, a map that matches the narrative, and a filing history that matches both. Change orders welcome — that is the entire point of the desk.