diff --git a/parsl/dataflow/dflow.py b/parsl/dataflow/dflow.py
index 344173c4b1..ac875308d5 100644
--- a/parsl/dataflow/dflow.py
+++ b/parsl/dataflow/dflow.py
@@ -93,7 +93,7 @@ def __init__(self, config: Config) -> None:
         self.run_dir = make_rundir(config.run_dir)
 
         if config.initialize_logging:
-            parsl.set_file_logger("{}/parsl.log".format(self.run_dir), level=logging.DEBUG)
+            _, self.logging_handler = parsl.set_file_logger("{}/parsl.log".format(self.run_dir), level=logging.DEBUG)
 
         logger.info("Starting DataFlowKernel with config\n{}".format(config))
 
@@ -1321,7 +1321,13 @@ def cleanup(self) -> None:
         else:
             logger.debug("Cleaning up non-default DFK - not unregistering")
 
-        logger.info("DFK cleanup complete")
+        # TODO: do this in parsl/logutils.py
+        logger.info("DFK cleanup complete - removing parsl.log handler")
+        logger_to_remove = logging.getLogger("parsl")
+        logger_to_remove.removeHandler(self.logging_handler)
+        self.logging_handler.close()
+
+        logger.info("handler closed - is this going to break things?")
 
     def checkpoint(self, tasks: Optional[Sequence[TaskRecord]] = None) -> str:
         """Checkpoint the dfk incrementally to a checkpoint file.
diff --git a/parsl/log_utils.py b/parsl/log_utils.py
index ff25249b1b..b5d483b8e6 100644
--- a/parsl/log_utils.py
+++ b/parsl/log_utils.py
@@ -12,7 +12,7 @@
 """
 import io
 import logging
-from typing import Optional
+from typing import Optional, Tuple
 
 import typeguard
 
@@ -65,7 +65,7 @@ def set_stream_logger(name: str = 'parsl',
 def set_file_logger(filename: str,
                     name: str = 'parsl',
                     level: int = logging.DEBUG,
-                    format_string: Optional[str] = None) -> logging.Logger:
+                    format_string: Optional[str] = None) -> Tuple[logging.Logger, logging.FileHandler]:
     """Add a file log handler.
 
     Args:
@@ -93,4 +93,4 @@ def set_file_logger(filename: str,
     futures_logger = logging.getLogger("concurrent.futures")
     futures_logger.addHandler(handler)
 
-    return logger
+    return (logger, handler)
diff --git a/parsl/monitoring/monitoring.py b/parsl/monitoring/monitoring.py
index d23f1a4700..5ee9282d09 100644
--- a/parsl/monitoring/monitoring.py
+++ b/parsl/monitoring/monitoring.py
@@ -288,9 +288,9 @@ def close(self) -> None:
 
 @wrap_with_logs
 def filesystem_receiver(logdir: str, q: "queue.Queue[AddressedMonitoringMessage]", run_dir: str) -> None:
-    logger = set_file_logger("{}/monitoring_filesystem_radio.log".format(logdir),
-                             name="monitoring_filesystem_radio",
-                             level=logging.INFO)
+    logger, _ = set_file_logger("{}/monitoring_filesystem_radio.log".format(logdir),
+                                name="monitoring_filesystem_radio",
+                                level=logging.INFO)
 
     logger.info("Starting filesystem radio receiver")
     setproctitle("parsl: monitoring filesystem receiver")
diff --git a/parsl/monitoring/router.py b/parsl/monitoring/router.py
index d397d8e6af..f87b86c7b4 100644
--- a/parsl/monitoring/router.py
+++ b/parsl/monitoring/router.py
@@ -65,9 +65,9 @@ def __init__(self,
             An event that the main Parsl process will set to signal that the monitoring router should shut down.
         """
         os.makedirs(logdir, exist_ok=True)
-        self.logger = set_file_logger("{}/monitoring_router.log".format(logdir),
-                                      name="monitoring_router",
-                                      level=logging_level)
+        self.logger, _ = set_file_logger("{}/monitoring_router.log".format(logdir),
+                                         name="monitoring_router",
+                                         level=logging_level)
         self.logger.debug("Monitoring router starting")
 
         self.hub_address = hub_address
diff --git a/parsl/tests/conftest.py b/parsl/tests/conftest.py
index 2e227904fa..5cf9446906 100644
--- a/parsl/tests/conftest.py
+++ b/parsl/tests/conftest.py
@@ -217,6 +217,9 @@ def load_dfk_session(request, pytestconfig, tmpd_cwd_session):
         logger.error(f"BENC: end open fds: {end_fds}")
 
         assert threading.active_count() == 1, "test left threads running: " + repr(threading.enumerate())
+        end_fds = this_process.num_fds()
+        logger.error(f"BENC: end open fds: {end_fds} (vs {start_fds} at start)")
+        assert start_fds == end_fds, "number of open fds changed across test run"
 
     else:
         yield
@@ -281,6 +284,12 @@ def load_dfk_local_module(request, pytestconfig, tmpd_cwd_session):
         logger.error(f"BENC: end threads: {threading.active_count()}")
 
         assert threading.active_count() == 1, "test left threads running: " + repr(threading.enumerate())
+        end_fds = this_process.num_fds()
+        logger.error(f"BENC: open fds END: {end_fds}")
+        if end_fds > start_fds:
+            logger.error(f"Open files (not all fds, though?): {this_process.open_files()!r}")
+            os.system(f"ls -l /proc/{os.getpid()}/fd")
+            pytest.fail("BENC: number of open fds increased across test")
 
     else:
         yield