Evidence
14 evidence entries recorded; each entry has a stable permalink (#ev-1 … #ev-14).
-
[1]research packet 1052-packet.md [other_primary]
- Finding type
- vessel_history
- Finding
- Identity packet verdict: VERIFIED
- Verification
- verified
- Role
- supporting
- Documentation level
- ship_specific
- Evidence ID
- uss-yms-323-yms323-pkt-1052-packet-md
-
[2]NavSource Online: Mine Warfare Vessel Photo Archive, YMS-323 - construction, milestones, specifications, disposition (live page, verified 200) [other_primary]
- Locator
- NavSource 11/19323.htm - timeline block, specifications block, commanding-officer table
- Finding type
- vessel_history
- Finding
- Timeline for this hull: laid down 26 February 1943 by the Al Larson Boat Shop, Inc., Terminal Island, CA; launched 15 July 1943; commissioned USS YMS-323, 27 December 1943; damaged by Japanese shore battery 18 June 1944 off Garapan, Saipan and again 19 June 1944 off Tanapag Harbor, Saipan; struck from the Naval Register 19 June 1946; transferred to the State Department Foreign Liquidation Commission April 1947; sold to South Korea 6 August 1947; commissioned Guwolsan (YMS 512), 11 November 1947; fate unknown. Spec block: YMS-1 class auxiliary motor minesweeper; displacement 270 t.; length 136'; beam 24'6"; draft 8'; speed 15 kts.; complement 32; armament one 3"/50 dual-purpose mount, two 20mm mounts, two depth-charge projectors; propulsion two 880bhp General Motors 8-268A diesel engines, Snow and Knobstedt single reduction gear, two shafts. Commanding officer listed: LTJG G. B. Harrison, USNR (1945). Call sign Nan-Queen-Able-Zebra. Page notes 'There is no DANFS History currently available for YMS-323.'
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1943-1947 (coverage)
- Population
- Al Larson construction trades (1943); crew (1943-46)
- Limitations
- NavSource is a volunteer secondary compilation, not a primary registry - its milestones generally track NVR/DANFS-type records but remain secondary sourcing. Vessel-history facts only; contains no asbestos or material content. Does not document a decommissioning date or final fate.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-01
-
[3]Official Chronology of the U.S. Navy in World War II, 1944 (HyperWar transcription of the official Navy chronology), entries for 18 June and 19 June 1944 [other_primary]
- Locator
- USN-Chron-1944, 18 June and 19 June 1944 Pacific entries
- Finding type
- historical_record
- Finding
- Official Navy chronology for this hull: 18 June 1944 - 'destroyer Phelps (DD-360), LCI(G)-371, and motor minesweeper YMS-323 are damaged by shore battery off Garapan, 14 deg 58'N, 146 deg 21'E.' 19 June 1944 - 'Motor minesweeper YMS-323 is damaged by shore battery, as she carries out survey operations off Tanapag Harbor, Saipan, 15 deg 10'N, 145 deg 58'E.'
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 18-19 June 1944
- Population
- YMS-323 crew (~32 complement)
- Limitations
- Official chronology entries establish the two damage events, dates, and positions; extent of damage and any casualties are not stated in these entries (the damage detail comes from the USMC monograph, ev-03). Combat-damage record only; no asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-02
-
[4]USMC historical monograph, 'Saipan: The Beginning of the End' (Carl W. Hoffman, Historical Division, HQMC, 1950), Chapter 3 (HyperWar transcription) [other_primary]
- Locator
- USMC-M-Saipan-3, 'Battle of the Philippine Sea' section, paragraph opening 'On 19 June, while conducting survey operations'
- Finding type
- historical_record
- Finding
- Official Marine Corps history records the 19 June 1944 damage: 'On 19 June, while conducting survey operations off Tanapag Harbor, a mine sweeper (YMS 323) received direct hits from a 4.7-inch battery on Mutcho Point. The ship was holed in two places below the waterline and a fire started forward near the magazine. Fortunately, the Japanese projectiles were armor piercing and did not explode. With the assistance of salvage tugs, the fire and flooding were brought under control.'
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 19 June 1944
- Population
- YMS-323 crew (~32 complement); salvage-tug crews
- Limitations
- Establishes the damage mechanism and fire/flooding outcome for the 19 June hit; does not state casualties or repair location/duration. Combat-damage record only; no asbestos content. Fire near the magazine and hull penetration below the waterline are documented events, not exposure events - no repair or material record attached.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-03
-
[5]USMC historical monograph, 'The Recapture of Guam' (O. Robert Lodge, Historical Branch, G-3 Division, HQMC, 1954), Appendix V, 'United States Ships Participating in the Guam Operation' (HyperWar transcription) [other_primary]
- Locator
- USMC-M-Guam Appendix V, MINE VESSELS list (YMS-323 paired with YMS-184 in the table)
- Finding type
- historical_record
- Finding
- YMS-323 is listed among MINE VESSELS in the official Marine Corps monograph's appendix of United States ships participating in the Guam operation (assault 21 July 1944, organized resistance ended 10 August 1944).
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- July-August 1944
- Population
- YMS-323 crew (~32 complement)
- Limitations
- A participation listing only - establishes presence in the Guam operation order of battle, not specific tasks, dates on station, or events for this hull. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-04
-
[6]NHHC Online Reading Room, 'United States Pacific Fleet Organization, 1 May 1945' - Mine Squadron TWENTY listing [other_primary]
- Locator
- PacFleet org 1 May 1945, MINE SQUADRON TWENTY section, YMS table row '94 | YMS 323 | Lt. J. R. Thompson (USNR)'
- Finding type
- historical_record
- Finding
- The Navy's published Pacific Fleet organization of 1 May 1945 lists 'YMS 323' under MINE SQUADRON TWENTY (Commander Mine Squadron Twenty, Capt. R. A. Larkin; flagship Ellyson, DMS-19), commanding officer Lt. J. R. Thompson (USNR).
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1 May 1945 (snapshot)
- Population
- YMS-323 crew (~32 complement)
- Limitations
- A one-day organizational snapshot - establishes unit assignment and commanding officer on 1 May 1945 only; does not state operating location or employment. NavSource's CO table separately lists LTJG G. B. Harrison, USNR, for 1945 - the two listings likely reflect different points in 1945 and are both reported. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-05
-
[7]National Archives, Special List #44 - List of Logbooks of US Navy Ships, Stations, and Miscellaneous Units, 1801-1947 (by ship number), RG 24 Entry 118 [other_primary]
- Locator
- sl-44-ship-number.pdf, PDF page 118, line 'YMS-323 12/27/1943 6/30/1945'
- Finding type
- historical_record
- Finding
- NARA Special List 44 inventories U.S. Navy deck logs for YMS-323 covering 27 December 1943 through 30 June 1945 - i.e., commissioning day through mid-1945, spanning the Saipan damage events and Guam operation. The logs are physical holdings in Records of the Bureau of Naval Personnel (RG 24), Entry 118.
- Verification
- verified
- Role
- archival_lead
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1943-12-27 to 1945-06-30 (log coverage)
- Population
- YMS-323 crew (~32 complement)
- Limitations
- Archival lead only: the inventory establishes that deck logs for this hull exist for the stated coverage window; the logs are NOT digitized (YMS-323 does not appear on the NARA online deck-logs list) and their contents were not examined - they document daily activities, not material content. Coverage ends 30 June 1945; any later-1945/1946 logs are outside the Special List 44 entry and are open leads. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-06
-
[8]U.S. Naval Academy Library, Special Collections & Archives, 'World War II Ship Action Reports, 1942-1945' finding aid, MS 415, Series 3 (Ships M-Z) [other_primary]
- Locator
- MS 415 finding aid, Series 3 Ships M-Z, entry 'U.S.S. YMS-323 (Minesweeper), June 1944. Action at Saipan.' (Box 22 Folder 47)
- Finding type
- historical_record
- Finding
- The USNA Special Collections finding aid inventories: 'U.S.S. YMS-323 (Minesweeper), June 1944. Action at Saipan.' - Box 22, Folder 47 - meaning a ship-generated action report covering the June 1944 Saipan events (the 18-19 June shore-battery damage) exists in the collection.
- Verification
- partial
- Role
- archival_lead
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- June 1944
- Population
- YMS-323 crew (~32 complement)
- Limitations
- Archival lead only: the finding aid establishes the report's existence and location; the report itself is not digitized and its contents were not examined. An action report may contain damage, casualty, and repair detail beyond the published chronology/monograph accounts. No asbestos content expected or established.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-07
-
[9]NHHC Online Reading Room, 'Essay on Naval Battles of the Korean War' (reproduced with permission from Tucker, ed., Encyclopedia of the Korean War, ABC-CLIO 2000) [other_primary]
- Locator
- Essay paragraph on late-August 1950 south-coast action
- Finding type
- historical_record
- Finding
- The NHHC-published essay documents this hull's Korean War service under its ROK Navy identity: 'Combat action was especially heavy on the south coast during the last week of August [1950]... Motor minesweepers YMS 503, YMS 504, YMS 512, and YMS 514, and PC 702 sank numerous enemy craft, many of whose embarked troops drowned, and captured many others.' YMS-512 is the ex-USS YMS-323 per the NavSource transfer/renaming record (ev-01).
- Verification
- verified
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- August 1950
- Population
- ROKN crew of YMS-512 (August 1950)
- Limitations
- Documents combat employment of ex-YMS-323 as ROKN YMS-512 in August 1950; the identity chain YMS-323 -> Guwolsan (YMS-512) rests on NavSource/secondary compilation, not on a primary registry document. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-08
-
[10]shipbuildinghistory.com, 'Yard Minesweepers YMS BYMS' table and Al Larson Boat Shop yard page (mirror: shipbuildinghistory.njscuba.net/us-comm-small/larson/) - secondary shipbuilding compilations; plus Al Larson Boat Shop official history page (larsonboat.com/historical/) for yard founding/location [other_primary]
- Locator
- shipbuildinghistory ym.htm row 'YMS 323 ... 27-Dec-43 | To South Korea 1948 as Ku Po, scrapped 1956'; larson/ yard table same row; NavSource 11/19323.htm disposition lines; https://www.larsonboat.com/historical/ (1903 founding, Fish Harbor)
- Finding type
- vessel_history
- Finding
- Name/fate conflict on Korean service: NavSource records the hull sold to South Korea 6 August 1947 and commissioned Guwolsan (YMS 512) 11 November 1947, fate unknown; shipbuildinghistory.com's YMS table and Al Larson yard table both carry 'to Korea 1948 as Ku Po, scrapped 1956.' The transfer year (1947 vs 1948), Korean name (Guwolsan vs Ku Po), and final disposition (unknown vs scrapped 1956) conflict across secondary sources; no primary disposition record was located. The yard table also confirms Al Larson Boat Shop's Navy output: at least YMS-86, -87, -320, -321, -322, -323, -324, -325 plus subchasers SC-734/735. The builder's own history page documents the yard established 1903 at Fish Harbor in the Port of Los Angeles and still operating.
- Verification
- partial
- Role
- correction
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1947-1956
- Population
- ROKN crew (1947 onward); shipbreakers (1956, if scrapping report accurate)
- Limitations
- Secondary compilations only - neither NavSource nor shipbuildinghistory is a primary registry; the Korean name and scrapping claim are unverified against Korean records. Not an asbestos finding.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-09
-
[11]officialmilitaryribbons.com, 'U.S. Navy Ships World War 2 Campaign Battle Stars' compilation, YMS 207-361 page - secondary transcription of the Navy's campaign-credit list [other_primary]
- Locator
- officialmilitaryribbons YMS 207-361 page, 'YMS 323:' table section
- Finding type
- historical_record
- Finding
- A secondary compilation of the Navy's WWII campaign-star list credits YMS-323 with six campaigns: Capture and occupation of Saipan (15 Jun-23 Jul 44, P29-2); Capture and occupation of Guam (24-28 Jul 44, P29-7); Assault and occupation of Iwo Jima (17-25 Feb 45, P33-1); Assault and occupation of Okinawa Gunto (26-30 Jun 45, P34-1); 3d Fleet operations against Japan (5-31 Jul 45, P35); and Nagoya, Honshu Area occupation duty (21-25 Oct 45, P207-3). The Saipan and Guam credits are corroborated by the official records in ev-02/-03/-04.
- Verification
- partial
- Role
- context
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 1944-1945 (campaign windows)
- Population
- YMS-323 crew (~32 complement)
- Limitations
- Secondary vendor compilation, not an official Navy source - the Iwo Jima, Okinawa, 3d Fleet, and Nagoya credits rest on this transcription alone and were not verified against the official OPNAV awards list (not located online). Consistent with the Mine Squadron TWENTY assignment (ev-05) and the Special List 44 log window ending 30 June 1945, but participation beyond Saipan and Guam is carried as partial verification. No asbestos content.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-10
-
[12]NavSource YMS/BYMS class index and shipbuildinghistory.com YMS table - class construction context; plus uboat.net YMS-323 entry (contract order date, secondary) [other_primary]
- Locator
- NavSource 11/19idx.htm class narrative; shipbuildinghistory ym.htm class preamble; NavSource 11/19323.htm spec block; uboat.net ship/9742.html
- Finding type
- asbestos_application
- Finding
- A wooden-hulled, diesel-powered minesweeper built in 1943 sits inside the Navy's documented asbestos-use era (see ev-12). Era-standard small-vessel applications for a boat of this type and period: engine and diesel-exhaust insulation/lagging, gaskets, valve packing, electrical insulation, and general shipboard materials in the confined 136-ft hull. As a diesel-mechanical boat she carried no steam plant - the boiler/turbine lagging pathway of steam vessels does not apply, and her wooden hull construction narrows the era-typical product set relative to steel steam vessels; the dominant exposure-relevant fact for the type is confined-space work around insulated machinery. Class context: 561 wooden-hulled YMS/BYMS built at 35 yacht yards spring 1942 - spring 1945; 481 for the USN; YMS-323 falls in the single-stack group (YMS-135 through -445); boats of this type did inshore sweeping ahead of amphibious assaults.
- Verification
- inferred
- Role
- supporting
- Documentation level
- class_or_era
- Accessed
- 2026-10-04
- Study period
- 1943-1950s
- Population
- Al Larson construction trades (1943); crew (1943-46); repair/salvage personnel after June 1944 damage; ROKN crew (1947 onward)
- Limitations
- Class/era inference only - no hull-specific insulation survey, material list, or work package located for YMS-323. Names era-standard applications, not confirmed installed materials; no quantity and no manufacturer attribution for this hull. Class statistics rest on the NavSource index and shipbuildinghistory (secondary compilations).
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-11
-
[13]GAO, Navy Efforts To Protect Workers From Asbestos Exposure, HRD-80-2 (Oct 18, 1979) [gao]
- Locator
- GAO product page HRD-80-2 (full text blocked, HTTP 403)
- Finding type
- gov_survey
- Finding
- GAO documented that the Navy used asbestos insulation extensively aboard ships and did not begin substituting alternative insulation materials until the early 1970s - spanning this hull's construction (1943) and entire U.S. service era (1943-46).
- Verification
- verified
- Role
- context
- Documentation level
- class_or_era
- Accessed
- 2026-10-04
- Study period
- 1979
- Population
- Navy shipyard workers; asbestos program review
- Limitations
- Program-level documentation; supports era context only, not any fact specific to this hull. Full text not retrieved (gao.gov returns HTTP 403 to automated fetch, confirmed 2026-10-04) - content via product-page description.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-12
-
[14]Batch-8952 search ledger (this record): NavSource ship/class pages; NARA Special List 44 PDF; USNA MS 415 finding aid; HyperWar USN chronology and USMC monographs; NHHC fleet-organization and Korean War essay pages; shipbuildinghistory YMS and Al Larson yard tables; uboat.net; officialmilitaryribbons compilation; Al Larson Boat Shop official site; GAO product page; CourtListener (see search_ledger for live status); secondary web litigation sweep [other_primary]
- Locator
- search_ledger rows sl-uss-yms-323-01 through -15
- Finding type
- historical_record
- Finding
- No qualifying ship-specific asbestos record located: no asbestos survey, abatement contract, hazmat disclosure, or verified litigation naming USS YMS-323 / ROKN YMS-512 was found in the public sources searched. Secondary web sweeps surfaced only generic law-firm minesweeper listicles (e.g., mesotheliomahope.com) naming no specific hull and asserting asbestos without primary sourcing - excluded by source policy.
- Verification
- verified
- Role
- negative_finding
- Documentation level
- ship_specific
- Accessed
- 2026-10-04
- Study period
- 2026-10-04
- Limitations
- Absence of a located public record does not prove absence of asbestos aboard - this hull has unusually rich ship-specific service documentation but zero material content. Deck logs (NARA RG 24 Entry 118, coverage ending 30 June 1945), the USNA action report (MS 415, Box 22 Folder 47), and any FLC/Korean transfer documents are undigitized leads. Does not establish or defeat any claim of exposure or legal eligibility.
- Atlas source
- true
- Evidence ID
- ev-uss-yms-323-13