Case Studies
Successful Repair and Internal Lining of Fiberglass Wastewater Tanks
Challenge
Fiber‑Reinforced‑Polymer (FRP) wastewater tanks at a chemical plant began leaking due to deterioration of the internal gel coat, resulting in delamination. External FRP patch repairs failed within six months and did not address the root cause. With active leaks posing compliance risks and cold weather approaching, a durable solution was needed within seven days.
The customer was considering replacing the tanks at an estimated cost of $450,000 and 10 – 14 days tie in. Further repair attempts using FRP patching externally was not providing a solution. Any option to affect a better solution had to be accomplished within 7 days.
Solution
The tanks were drained and pressure washed to remove trace waste product. Following pressure washing, the tanks were allowed to air dry and then were lightly “sweep” sandblasted with garnet abrasive to create an clean anchor pattern. ARC S7 was used as a chemically resistant saturant with fiberglass cloth to rebuild wall thickness. Structurally compromised areas were repaired with carbon fiber and ARC S7. Finally, two alternating sealer coats of ARC S7 were applied at a total dry film thickness of 15 – 20 mils.
ARC S7.
Results
The client was happy that all work occurred within the short turn around required. The internal lining was applied in 2024 and, upon inspection after 18 months in service, showed no evidence of blistering, erosion, chemical attack, or through‑film delamination. Following the lining of an initial set of tanks, several more tanks were lined with ARC S7 in a similar fashion.
Savings
Previous repairs: $25,000 – $30,000/year (failures appearing within 18 months)
Estimated cost to replace 3 failing tanks: $450,000 (10 – 14 days to tie into existing piping)
ARC S7 and fiberglass repairs: $166,000 (7 days on site)
Total estimated savings: $284,000
$ = USD
About Us
Chesterton® is a world leader in helping process industry companies and manufacturers improve the reliability and efficiency of their rotating, stationary, and fluid power equipment platforms. We are known across a wide range of industries for our award-winning pump and valve sealing solutions, applications expertise, equipment maintenance and wear-prevention products, and knowledgeable hands-on local service. Chesterton product range includes mechanical seals, packing and gaskets, industrial lubricants and coatings.
® Registered trademark owned by A.W. Chesterton Company
EN602481. Issued 06/2026
Technical data reflects results of laboratory tests and is intended to indicate general characteristics only. A.W. Chesterton Company disclaims all warranties expressed or implied, including warranties of merchantability and fitness for a particular purpose. Liability, if any, is limited to product replacement only. Any images contained herein are for general illustrative or aesthetic purposes only and are not intended to convey any instructional, safety, handling, or usage information or advice respecting any product or equipment. Please refer to relevant Safety Data Sheets, Product Data Sheets, and/or Product Labels for safe use, storage, handling, and disposal of products, or consult with your local Chesterton sales representative.