Welsh Water Authority including Taff Division - Aberystwyth Sewerage: proposed trunk sewer from Park Avenue to the pumping station at Tan-y-Cae, including site investigation; Alwen Treatment Works including contractual Claim; Llandegfedd Reservoir: emergency by-pass pipeline main; proposed deep cutting, M4 motorway (from Castleton to Coryton), adjoining the Wenallt Service Reservoir.
Test data, maps, plans, notes, reports, notebooks, correspondence, A.H.S. Waters & Partners and site investigation material, copy material dating back to the 1940s, glass negatives (marked Marple[?s Ridgway] 1, 2, and 3 respectively), borehole logs, calculations, photographs, laboratory test results and other tests (Geo-Research Ltd), etc.